CINXE.COM

<!DOCTYPE html> <html class="client-nojs vector-feature-language-in-header-enabled vector-feature-language-in-main-page-header-disabled vector-feature-sticky-header-disabled vector-feature-page-tools-pinned-disabled vector-feature-toc-pinned-clientpref-1 vector-feature-main-menu-pinned-disabled vector-feature-limited-width-clientpref-1 vector-feature-limited-width-content-enabled vector-feature-custom-font-size-clientpref-1 vector-feature-appearance-pinned-clientpref-1 vector-feature-night-mode-enabled skin-theme-clientpref-day vector-toc-available" lang="en" dir="ltr"> <head> <meta charset="UTF-8"> <title>Cognitive radio - Wikipedia</title> <script>(function(){var className="client-js vector-feature-language-in-header-enabled vector-feature-language-in-main-page-header-disabled vector-feature-sticky-header-disabled vector-feature-page-tools-pinned-disabled vector-feature-toc-pinned-clientpref-1 vector-feature-main-menu-pinned-disabled vector-feature-limited-width-clientpref-1 vector-feature-limited-width-content-enabled vector-feature-custom-font-size-clientpref-1 vector-feature-appearance-pinned-clientpref-1 vector-feature-night-mode-enabled skin-theme-clientpref-day vector-toc-available";var cookie=document.cookie.match(/(?:^|; )enwikimwclientpreferences=([^;]+)/);if(cookie){cookie[1].split('%2C').forEach(function(pref){className=className.replace(new RegExp('(^| )'+pref.replace(/-clientpref-\w+$|[^\w-]+/g,'')+'-clientpref-\\w+( |$)'),'$1'+pref+'$2');});}document.documentElement.className=className;}());RLCONF={"wgBreakFrames":false,"wgSeparatorTransformTable":["",""],"wgDigitTransformTable":["",""],"wgDefaultDateFormat":"dmy", "wgMonthNames":["","January","February","March","April","May","June","July","August","September","October","November","December"],"wgRequestId":"3cbc5958-17c5-4c5c-b802-2de826ad0b66","wgCanonicalNamespace":"","wgCanonicalSpecialPageName":false,"wgNamespaceNumber":0,"wgPageName":"Cognitive_radio","wgTitle":"Cognitive radio","wgCurRevisionId":1260832972,"wgRevisionId":1260832972,"wgArticleId":1000682,"wgIsArticle":true,"wgIsRedirect":false,"wgAction":"view","wgUserName":null,"wgUserGroups":["*"],"wgCategories":["Articles with short description","Short description is different from Wikidata","Use dmy dates from June 2023","All articles with unsourced statements","Articles with unsourced statements from January 2009","Radio technology","Wireless networking","Radio resource management","Radiofrequency receivers","Telecommunications engineering"],"wgPageViewLanguage":"en","wgPageContentLanguage":"en","wgPageContentModel":"wikitext","wgRelevantPageName":"Cognitive_radio","wgRelevantArticleId" :1000682,"wgIsProbablyEditable":true,"wgRelevantPageIsProbablyEditable":true,"wgRestrictionEdit":[],"wgRestrictionMove":[],"wgNoticeProject":"wikipedia","wgCiteReferencePreviewsActive":false,"wgFlaggedRevsParams":{"tags":{"status":{"levels":1}}},"wgMediaViewerOnClick":true,"wgMediaViewerEnabledByDefault":true,"wgPopupsFlags":0,"wgVisualEditor":{"pageLanguageCode":"en","pageLanguageDir":"ltr","pageVariantFallbacks":"en"},"wgMFDisplayWikibaseDescriptions":{"search":true,"watchlist":true,"tagline":false,"nearby":true},"wgWMESchemaEditAttemptStepOversample":false,"wgWMEPageLength":40000,"wgRelatedArticlesCompat":[],"wgEditSubmitButtonLabelPublish":true,"wgULSPosition":"interlanguage","wgULSisCompactLinksEnabled":false,"wgVector2022LanguageInHeader":true,"wgULSisLanguageSelectorEmpty":false,"wgWikibaseItemId":"Q3235733","wgCheckUserClientHintsHeadersJsApi":["brands","architecture","bitness","fullVersionList","mobile","model","platform","platformVersion"], "GEHomepageSuggestedEditsEnableTopics":true,"wgGETopicsMatchModeEnabled":false,"wgGEStructuredTaskRejectionReasonTextInputEnabled":false,"wgGELevelingUpEnabledForUser":false};RLSTATE={"ext.globalCssJs.user.styles":"ready","site.styles":"ready","user.styles":"ready","ext.globalCssJs.user":"ready","user":"ready","user.options":"loading","ext.cite.styles":"ready","skins.vector.search.codex.styles":"ready","skins.vector.styles":"ready","skins.vector.icons":"ready","jquery.tablesorter.styles":"ready","ext.wikimediamessages.styles":"ready","ext.visualEditor.desktopArticleTarget.noscript":"ready","ext.uls.interlanguage":"ready","wikibase.client.init":"ready","ext.wikimediaBadges":"ready"};RLPAGEMODULES=["ext.cite.ux-enhancements","site","mediawiki.page.ready","jquery.tablesorter","mediawiki.toc","skins.vector.js","ext.centralNotice.geoIP","ext.centralNotice.startUp","ext.gadget.ReferenceTooltips","ext.gadget.switcher","ext.urlShortener.toolbar","ext.centralauth.centralautologin","ext.popups", "ext.visualEditor.desktopArticleTarget.init","ext.visualEditor.targetLoader","ext.echo.centralauth","ext.eventLogging","ext.wikimediaEvents","ext.navigationTiming","ext.uls.interface","ext.cx.eventlogging.campaigns","ext.cx.uls.quick.actions","wikibase.client.vector-2022","ext.checkUser.clientHints","ext.quicksurveys.init","ext.growthExperiments.SuggestedEditSession","wikibase.sidebar.tracking"];</script> <script>(RLQ=window.RLQ||[]).push(function(){mw.loader.impl(function(){return["user.options@12s5i",function($,jQuery,require,module){mw.user.tokens.set({"patrolToken":"+\\","watchToken":"+\\","csrfToken":"+\\"}); }];});});</script> <link rel="stylesheet" href="/w/load.php?lang=en&modules=ext.cite.styles%7Cext.uls.interlanguage%7Cext.visualEditor.desktopArticleTarget.noscript%7Cext.wikimediaBadges%7Cext.wikimediamessages.styles%7Cjquery.tablesorter.styles%7Cskins.vector.icons%2Cstyles%7Cskins.vector.search.codex.styles%7Cwikibase.client.init&only=styles&skin=vector-2022"> <script async="" src="/w/load.php?lang=en&modules=startup&only=scripts&raw=1&skin=vector-2022"></script> <meta name="ResourceLoaderDynamicStyles" content=""> <link rel="stylesheet" href="/w/load.php?lang=en&modules=site.styles&only=styles&skin=vector-2022"> <meta name="generator" content="MediaWiki 1.44.0-wmf.5"> <meta name="referrer" content="origin"> <meta name="referrer" content="origin-when-cross-origin"> <meta name="robots" content="max-image-preview:standard"> <meta name="format-detection" content="telephone=no"> <meta name="viewport" content="width=1120"> <meta property="og:title" content="Cognitive radio - Wikipedia"> <meta property="og:type" content="website"> <link rel="alternate" media="only screen and (max-width: 640px)" href="//en.m.wikipedia.org/wiki/Cognitive_radio"> <link rel="alternate" type="application/x-wiki" title="Edit this page" href="/w/index.php?title=Cognitive_radio&action=edit"> <link rel="apple-touch-icon" href="/static/apple-touch/wikipedia.png"> <link rel="icon" href="/static/favicon/wikipedia.ico"> <link rel="search" type="application/opensearchdescription+xml" href="/w/rest.php/v1/search" title="Wikipedia (en)"> <link rel="EditURI" type="application/rsd+xml" href="//en.wikipedia.org/w/api.php?action=rsd"> <link rel="canonical" href="https://en.wikipedia.org/wiki/Cognitive_radio"> <link rel="license" href="https://creativecommons.org/licenses/by-sa/4.0/deed.en"> <link rel="alternate" type="application/atom+xml" title="Wikipedia Atom feed" href="/w/index.php?title=Special:RecentChanges&feed=atom"> <link rel="dns-prefetch" href="//meta.wikimedia.org" /> <link rel="dns-prefetch" href="//login.wikimedia.org"> </head> <body class="skin--responsive skin-vector skin-vector-search-vue mediawiki ltr sitedir-ltr mw-hide-empty-elt ns-0 ns-subject mw-editable page-Cognitive_radio rootpage-Cognitive_radio skin-vector-2022 action-view"><a class="mw-jump-link" href="#bodyContent">Jump to content</a> <div class="vector-header-container"> <header class="vector-header mw-header"> <div class="vector-header-start"> <nav class="vector-main-menu-landmark" aria-label="Site"> <div id="vector-main-menu-dropdown" class="vector-dropdown vector-main-menu-dropdown vector-button-flush-left vector-button-flush-right" > <input type="checkbox" id="vector-main-menu-dropdown-checkbox" role="button" aria-haspopup="true" data-event-name="ui.dropdown-vector-main-menu-dropdown" class="vector-dropdown-checkbox " aria-label="Main menu" > <label id="vector-main-menu-dropdown-label" for="vector-main-menu-dropdown-checkbox" class="vector-dropdown-label cdx-button cdx-button--fake-button cdx-button--fake-button--enabled cdx-button--weight-quiet cdx-button--icon-only " aria-hidden="true" ><span class="vector-icon mw-ui-icon-menu mw-ui-icon-wikimedia-menu"></span> <span class="vector-dropdown-label-text">Main menu</span> </label> <div class="vector-dropdown-content"> <div id="vector-main-menu-unpinned-container" class="vector-unpinned-container"> <div id="vector-main-menu" class="vector-main-menu vector-pinnable-element"> <div class="vector-pinnable-header vector-main-menu-pinnable-header vector-pinnable-header-unpinned" data-feature-name="main-menu-pinned" data-pinnable-element-id="vector-main-menu" data-pinned-container-id="vector-main-menu-pinned-container" data-unpinned-container-id="vector-main-menu-unpinned-container" > <div class="vector-pinnable-header-label">Main menu</div> <button class="vector-pinnable-header-toggle-button vector-pinnable-header-pin-button" data-event-name="pinnable-header.vector-main-menu.pin">move to sidebar</button> <button class="vector-pinnable-header-toggle-button vector-pinnable-header-unpin-button" data-event-name="pinnable-header.vector-main-menu.unpin">hide</button> </div> <div id="p-navigation" class="vector-menu mw-portlet mw-portlet-navigation" > <div class="vector-menu-heading"> Navigation </div> <div class="vector-menu-content"> <ul class="vector-menu-content-list"> <li id="n-mainpage-description" class="mw-list-item"><a href="/wiki/Main_Page" title="Visit the main page [z]" accesskey="z"><span>Main page</span></a></li><li id="n-contents" class="mw-list-item"><a href="/wiki/Wikipedia:Contents" title="Guides to browsing Wikipedia"><span>Contents</span></a></li><li id="n-currentevents" class="mw-list-item"><a href="/wiki/Portal:Current_events" title="Articles related to current events"><span>Current events</span></a></li><li id="n-randompage" class="mw-list-item"><a href="/wiki/Special:Random" title="Visit a randomly selected article [x]" accesskey="x"><span>Random article</span></a></li><li id="n-aboutsite" class="mw-list-item"><a href="/wiki/Wikipedia:About" title="Learn about Wikipedia and how it works"><span>About Wikipedia</span></a></li><li id="n-contactpage" class="mw-list-item"><a href="//en.wikipedia.org/wiki/Wikipedia:Contact_us" title="How to contact Wikipedia"><span>Contact us</span></a></li> </ul> </div> </div> <div id="p-interaction" class="vector-menu mw-portlet mw-portlet-interaction" > <div class="vector-menu-heading"> Contribute </div> <div class="vector-menu-content"> <ul class="vector-menu-content-list"> <li id="n-help" class="mw-list-item"><a href="/wiki/Help:Contents" title="Guidance on how to use and edit Wikipedia"><span>Help</span></a></li><li id="n-introduction" class="mw-list-item"><a href="/wiki/Help:Introduction" title="Learn how to edit Wikipedia"><span>Learn to edit</span></a></li><li id="n-portal" class="mw-list-item"><a href="/wiki/Wikipedia:Community_portal" title="The hub for editors"><span>Community portal</span></a></li><li id="n-recentchanges" class="mw-list-item"><a href="/wiki/Special:RecentChanges" title="A list of recent changes to Wikipedia [r]" accesskey="r"><span>Recent changes</span></a></li><li id="n-upload" class="mw-list-item"><a href="/wiki/Wikipedia:File_upload_wizard" title="Add images or other media for use on Wikipedia"><span>Upload file</span></a></li> </ul> </div> </div> </div> </div> </div> </div> </nav> <a href="/wiki/Main_Page" class="mw-logo"> <img class="mw-logo-icon" src="/static/images/icons/wikipedia.png" alt="" aria-hidden="true" height="50" width="50"> <span class="mw-logo-container skin-invert"> <img class="mw-logo-wordmark" alt="Wikipedia" src="/static/images/mobile/copyright/wikipedia-wordmark-en.svg" style="width: 7.5em; height: 1.125em;"> <img class="mw-logo-tagline" alt="The Free Encyclopedia" src="/static/images/mobile/copyright/wikipedia-tagline-en.svg" width="117" height="13" style="width: 7.3125em; height: 0.8125em;"> </span> </a> </div> <div class="vector-header-end"> <div id="p-search" role="search" class="vector-search-box-vue vector-search-box-collapses vector-search-box-show-thumbnail vector-search-box-auto-expand-width vector-search-box"> <a href="/wiki/Special:Search" class="cdx-button cdx-button--fake-button cdx-button--fake-button--enabled cdx-button--weight-quiet cdx-button--icon-only search-toggle" title="Search Wikipedia [f]" accesskey="f"><span class="vector-icon mw-ui-icon-search mw-ui-icon-wikimedia-search"></span> <span>Search</span> </a> <div class="vector-typeahead-search-container"> <div class="cdx-typeahead-search cdx-typeahead-search--show-thumbnail cdx-typeahead-search--auto-expand-width"> <form action="/w/index.php" id="searchform" class="cdx-search-input cdx-search-input--has-end-button"> <div id="simpleSearch" class="cdx-search-input__input-wrapper" data-search-loc="header-moved"> <div class="cdx-text-input cdx-text-input--has-start-icon"> <input class="cdx-text-input__input" type="search" name="search" placeholder="Search Wikipedia" aria-label="Search Wikipedia" autocapitalize="sentences" title="Search Wikipedia [f]" accesskey="f" id="searchInput" > <span class="cdx-text-input__icon cdx-text-input__start-icon"></span> </div> <input type="hidden" name="title" value="Special:Search"> </div> <button class="cdx-button cdx-search-input__end-button">Search</button> </form> </div> </div> </div> <nav class="vector-user-links vector-user-links-wide" aria-label="Personal tools"> <div class="vector-user-links-main"> <div id="p-vector-user-menu-preferences" class="vector-menu mw-portlet emptyPortlet" > <div class="vector-menu-content"> <ul class="vector-menu-content-list"> </ul> </div> </div> <div id="p-vector-user-menu-userpage" class="vector-menu mw-portlet emptyPortlet" > <div class="vector-menu-content"> <ul class="vector-menu-content-list"> </ul> </div> </div> <nav class="vector-appearance-landmark" aria-label="Appearance"> <div id="vector-appearance-dropdown" class="vector-dropdown " title="Change the appearance of the page's font size, width, and color" > <input type="checkbox" id="vector-appearance-dropdown-checkbox" role="button" aria-haspopup="true" data-event-name="ui.dropdown-vector-appearance-dropdown" class="vector-dropdown-checkbox " aria-label="Appearance" > <label id="vector-appearance-dropdown-label" for="vector-appearance-dropdown-checkbox" class="vector-dropdown-label cdx-button cdx-button--fake-button cdx-button--fake-button--enabled cdx-button--weight-quiet cdx-button--icon-only " aria-hidden="true" ><span class="vector-icon mw-ui-icon-appearance mw-ui-icon-wikimedia-appearance"></span> <span class="vector-dropdown-label-text">Appearance</span> </label> <div class="vector-dropdown-content"> <div id="vector-appearance-unpinned-container" class="vector-unpinned-container"> </div> </div> </div> </nav> <div id="p-vector-user-menu-notifications" class="vector-menu mw-portlet emptyPortlet" > <div class="vector-menu-content"> <ul class="vector-menu-content-list"> </ul> </div> </div> <div id="p-vector-user-menu-overflow" class="vector-menu mw-portlet" > <div class="vector-menu-content"> <ul class="vector-menu-content-list"> <li id="pt-sitesupport-2" class="user-links-collapsible-item mw-list-item user-links-collapsible-item"><a data-mw="interface" href="https://donate.wikimedia.org/wiki/Special:FundraiserRedirector?utm_source=donate&utm_medium=sidebar&utm_campaign=C13_en.wikipedia.org&uselang=en" class=""><span>Donate</span></a> </li> <li id="pt-createaccount-2" class="user-links-collapsible-item mw-list-item user-links-collapsible-item"><a data-mw="interface" href="/w/index.php?title=Special:CreateAccount&returnto=Cognitive+radio" title="You are encouraged to create an account and log in; however, it is not mandatory" class=""><span>Create account</span></a> </li> <li id="pt-login-2" class="user-links-collapsible-item mw-list-item user-links-collapsible-item"><a data-mw="interface" href="/w/index.php?title=Special:UserLogin&returnto=Cognitive+radio" title="You're encouraged to log in; however, it's not mandatory. [o]" accesskey="o" class=""><span>Log in</span></a> </li> </ul> </div> </div> </div> <div id="vector-user-links-dropdown" class="vector-dropdown vector-user-menu vector-button-flush-right vector-user-menu-logged-out" title="Log in and more options" > <input type="checkbox" id="vector-user-links-dropdown-checkbox" role="button" aria-haspopup="true" data-event-name="ui.dropdown-vector-user-links-dropdown" class="vector-dropdown-checkbox " aria-label="Personal tools" > <label id="vector-user-links-dropdown-label" for="vector-user-links-dropdown-checkbox" class="vector-dropdown-label cdx-button cdx-button--fake-button cdx-button--fake-button--enabled cdx-button--weight-quiet cdx-button--icon-only " aria-hidden="true" ><span class="vector-icon mw-ui-icon-ellipsis mw-ui-icon-wikimedia-ellipsis"></span> <span class="vector-dropdown-label-text">Personal tools</span> </label> <div class="vector-dropdown-content"> <div id="p-personal" class="vector-menu mw-portlet mw-portlet-personal user-links-collapsible-item" title="User menu" > <div class="vector-menu-content"> <ul class="vector-menu-content-list"> <li id="pt-sitesupport" class="user-links-collapsible-item mw-list-item"><a href="https://donate.wikimedia.org/wiki/Special:FundraiserRedirector?utm_source=donate&utm_medium=sidebar&utm_campaign=C13_en.wikipedia.org&uselang=en"><span>Donate</span></a></li><li id="pt-createaccount" class="user-links-collapsible-item mw-list-item"><a href="/w/index.php?title=Special:CreateAccount&returnto=Cognitive+radio" title="You are encouraged to create an account and log in; however, it is not mandatory"><span class="vector-icon mw-ui-icon-userAdd mw-ui-icon-wikimedia-userAdd"></span> <span>Create account</span></a></li><li id="pt-login" class="user-links-collapsible-item mw-list-item"><a href="/w/index.php?title=Special:UserLogin&returnto=Cognitive+radio" title="You're encouraged to log in; however, it's not mandatory. [o]" accesskey="o"><span class="vector-icon mw-ui-icon-logIn mw-ui-icon-wikimedia-logIn"></span> <span>Log in</span></a></li> </ul> </div> </div> <div id="p-user-menu-anon-editor" class="vector-menu mw-portlet mw-portlet-user-menu-anon-editor" > <div class="vector-menu-heading"> Pages for logged out editors <a href="/wiki/Help:Introduction" aria-label="Learn more about editing"><span>learn more</span></a> </div> <div class="vector-menu-content"> <ul class="vector-menu-content-list"> <li id="pt-anoncontribs" class="mw-list-item"><a href="/wiki/Special:MyContributions" title="A list of edits made from this IP address [y]" accesskey="y"><span>Contributions</span></a></li><li id="pt-anontalk" class="mw-list-item"><a href="/wiki/Special:MyTalk" title="Discussion about edits from this IP address [n]" accesskey="n"><span>Talk</span></a></li> </ul> </div> </div> </div> </div> </nav> </div> </header> </div> <div class="mw-page-container"> <div class="mw-page-container-inner"> <div class="vector-sitenotice-container"> <div id="siteNotice"></div> </div> <div class="vector-column-start"> <div class="vector-main-menu-container"> <div id="mw-navigation"> <nav id="mw-panel" class="vector-main-menu-landmark" aria-label="Site"> <div id="vector-main-menu-pinned-container" class="vector-pinned-container"> </div> </nav> </div> </div> <div class="vector-sticky-pinned-container"> <nav id="mw-panel-toc" aria-label="Contents" data-event-name="ui.sidebar-toc" class="mw-table-of-contents-container vector-toc-landmark"> <div id="vector-toc-pinned-container" class="vector-pinned-container"> <div id="vector-toc" class="vector-toc vector-pinnable-element"> <div class="vector-pinnable-header vector-toc-pinnable-header vector-pinnable-header-pinned" data-feature-name="toc-pinned" data-pinnable-element-id="vector-toc" > <h2 class="vector-pinnable-header-label">Contents</h2> <button class="vector-pinnable-header-toggle-button vector-pinnable-header-pin-button" data-event-name="pinnable-header.vector-toc.pin">move to sidebar</button> <button class="vector-pinnable-header-toggle-button vector-pinnable-header-unpin-button" data-event-name="pinnable-header.vector-toc.unpin">hide</button> </div> <ul class="vector-toc-contents" id="mw-panel-toc-list"> <li id="toc-mw-content-text" class="vector-toc-list-item vector-toc-level-1"> <a href="#" class="vector-toc-link"> <div class="vector-toc-text">(Top)</div> </a> </li> <li id="toc-Description" class="vector-toc-list-item vector-toc-level-1 vector-toc-list-item-expanded"> <a class="vector-toc-link" href="#Description"> <div class="vector-toc-text"> <span class="vector-toc-numb">1</span> <span>Description</span> </div> </a> <ul id="toc-Description-sublist" class="vector-toc-list"> </ul> </li> <li id="toc-History" class="vector-toc-list-item vector-toc-level-1 vector-toc-list-item-expanded"> <a class="vector-toc-link" href="#History"> <div class="vector-toc-text"> <span class="vector-toc-numb">2</span> <span>History</span> </div> </a> <ul id="toc-History-sublist" class="vector-toc-list"> </ul> </li> <li id="toc-Terminology" class="vector-toc-list-item vector-toc-level-1 vector-toc-list-item-expanded"> <a class="vector-toc-link" href="#Terminology"> <div class="vector-toc-text"> <span class="vector-toc-numb">3</span> <span>Terminology</span> </div> </a> <ul id="toc-Terminology-sublist" class="vector-toc-list"> </ul> </li> <li id="toc-Technology" class="vector-toc-list-item vector-toc-level-1 vector-toc-list-item-expanded"> <a class="vector-toc-link" href="#Technology"> <div class="vector-toc-text"> <span class="vector-toc-numb">4</span> <span>Technology</span> </div> </a> <button aria-controls="toc-Technology-sublist" class="cdx-button cdx-button--weight-quiet cdx-button--icon-only vector-toc-toggle"> <span class="vector-icon mw-ui-icon-wikimedia-expand"></span> <span>Toggle Technology subsection</span> </button> <ul id="toc-Technology-sublist" class="vector-toc-list"> <li id="toc-Functions" class="vector-toc-list-item vector-toc-level-2"> <a class="vector-toc-link" href="#Functions"> <div class="vector-toc-text"> <span class="vector-toc-numb">4.1</span> <span>Functions</span> </div> </a> <ul id="toc-Functions-sublist" class="vector-toc-list"> </ul> </li> <li id="toc-Intelligent_antenna_(IA)" class="vector-toc-list-item vector-toc-level-2"> <a class="vector-toc-link" href="#Intelligent_antenna_(IA)"> <div class="vector-toc-text"> <span class="vector-toc-numb">4.2</span> <span>Intelligent antenna (IA)</span> </div> </a> <ul id="toc-Intelligent_antenna_(IA)-sublist" class="vector-toc-list"> </ul> </li> </ul> </li> <li id="toc-Applications" class="vector-toc-list-item vector-toc-level-1 vector-toc-list-item-expanded"> <a class="vector-toc-link" href="#Applications"> <div class="vector-toc-text"> <span class="vector-toc-numb">5</span> <span>Applications</span> </div> </a> <ul id="toc-Applications-sublist" class="vector-toc-list"> </ul> </li> <li id="toc-Simulation_of_CR_networks" class="vector-toc-list-item vector-toc-level-1 vector-toc-list-item-expanded"> <a class="vector-toc-link" href="#Simulation_of_CR_networks"> <div class="vector-toc-text"> <span class="vector-toc-numb">6</span> <span>Simulation of CR networks</span> </div> </a> <ul id="toc-Simulation_of_CR_networks-sublist" class="vector-toc-list"> </ul> </li> <li id="toc-Future_plans" class="vector-toc-list-item vector-toc-level-1 vector-toc-list-item-expanded"> <a class="vector-toc-link" href="#Future_plans"> <div class="vector-toc-text"> <span class="vector-toc-numb">7</span> <span>Future plans</span> </div> </a> <ul id="toc-Future_plans-sublist" class="vector-toc-list"> </ul> </li> <li id="toc-See_also" class="vector-toc-list-item vector-toc-level-1 vector-toc-list-item-expanded"> <a class="vector-toc-link" href="#See_also"> <div class="vector-toc-text"> <span class="vector-toc-numb">8</span> <span>See also</span> </div> </a> <ul id="toc-See_also-sublist" class="vector-toc-list"> </ul> </li> <li id="toc-References" class="vector-toc-list-item vector-toc-level-1 vector-toc-list-item-expanded"> <a class="vector-toc-link" href="#References"> <div class="vector-toc-text"> <span class="vector-toc-numb">9</span> <span>References</span> </div> </a> <ul id="toc-References-sublist" class="vector-toc-list"> </ul> </li> <li id="toc-External_links" class="vector-toc-list-item vector-toc-level-1 vector-toc-list-item-expanded"> <a class="vector-toc-link" href="#External_links"> <div class="vector-toc-text"> <span class="vector-toc-numb">10</span> <span>External links</span> </div> </a> <ul id="toc-External_links-sublist" class="vector-toc-list"> </ul> </li> </ul> </div> </div> </nav> </div> </div> <div class="mw-content-container"> <main id="content" class="mw-body"> <header class="mw-body-header vector-page-titlebar"> <nav aria-label="Contents" class="vector-toc-landmark"> <div id="vector-page-titlebar-toc" class="vector-dropdown vector-page-titlebar-toc vector-button-flush-left" > <input type="checkbox" id="vector-page-titlebar-toc-checkbox" role="button" aria-haspopup="true" data-event-name="ui.dropdown-vector-page-titlebar-toc" class="vector-dropdown-checkbox " aria-label="Toggle the table of contents" > <label id="vector-page-titlebar-toc-label" for="vector-page-titlebar-toc-checkbox" class="vector-dropdown-label cdx-button cdx-button--fake-button cdx-button--fake-button--enabled cdx-button--weight-quiet cdx-button--icon-only " aria-hidden="true" ><span class="vector-icon mw-ui-icon-listBullet mw-ui-icon-wikimedia-listBullet"></span> <span class="vector-dropdown-label-text">Toggle the table of contents</span> </label> <div class="vector-dropdown-content"> <div id="vector-page-titlebar-toc-unpinned-container" class="vector-unpinned-container"> </div> </div> </div> </nav> <h1 id="firstHeading" class="firstHeading mw-first-heading"><span class="mw-page-title-main">Cognitive radio</span></h1> <div id="p-lang-btn" class="vector-dropdown mw-portlet mw-portlet-lang" > <input type="checkbox" id="p-lang-btn-checkbox" role="button" aria-haspopup="true" data-event-name="ui.dropdown-p-lang-btn" class="vector-dropdown-checkbox mw-interlanguage-selector" aria-label="Go to an article in another language. Available in 13 languages" > <label id="p-lang-btn-label" for="p-lang-btn-checkbox" class="vector-dropdown-label cdx-button cdx-button--fake-button cdx-button--fake-button--enabled cdx-button--weight-quiet cdx-button--action-progressive mw-portlet-lang-heading-13" aria-hidden="true" ><span class="vector-icon mw-ui-icon-language-progressive mw-ui-icon-wikimedia-language-progressive"></span> <span class="vector-dropdown-label-text">13 languages</span> </label> <div class="vector-dropdown-content"> <div class="vector-menu-content"> <ul class="vector-menu-content-list"> <li class="interlanguage-link interwiki-ar mw-list-item"><a href="https://ar.wikipedia.org/wiki/%D8%B1%D8%A7%D8%AF%D9%8A%D9%88_%D8%A5%D8%AF%D8%B1%D8%A7%D9%83%D9%8A" title="راديو إدراكي – Arabic" lang="ar" hreflang="ar" data-title="راديو إدراكي" data-language-autonym="العربية" data-language-local-name="Arabic" class="interlanguage-link-target"><span>العربية</span></a></li><li class="interlanguage-link interwiki-bg mw-list-item"><a href="https://bg.wikipedia.org/wiki/%D0%9C%D0%B8%D1%81%D0%BB%D0%B5%D1%89%D0%BE_%D1%80%D0%B0%D0%B4%D0%B8%D0%BE" title="Мислещо радио – Bulgarian" lang="bg" hreflang="bg" data-title="Мислещо радио" data-language-autonym="Български" data-language-local-name="Bulgarian" class="interlanguage-link-target"><span>Български</span></a></li><li class="interlanguage-link interwiki-ca mw-list-item"><a href="https://ca.wikipedia.org/wiki/R%C3%A0dio_cognitiva" title="Ràdio cognitiva – Catalan" lang="ca" hreflang="ca" data-title="Ràdio cognitiva" data-language-autonym="Català" data-language-local-name="Catalan" class="interlanguage-link-target"><span>Català</span></a></li><li class="interlanguage-link interwiki-et mw-list-item"><a href="https://et.wikipedia.org/wiki/Kognitiivne_raadio" title="Kognitiivne raadio – Estonian" lang="et" hreflang="et" data-title="Kognitiivne raadio" data-language-autonym="Eesti" data-language-local-name="Estonian" class="interlanguage-link-target"><span>Eesti</span></a></li><li class="interlanguage-link interwiki-es mw-list-item"><a href="https://es.wikipedia.org/wiki/Radio_cognitiva" title="Radio cognitiva – Spanish" lang="es" hreflang="es" data-title="Radio cognitiva" data-language-autonym="Español" data-language-local-name="Spanish" class="interlanguage-link-target"><span>Español</span></a></li><li class="interlanguage-link interwiki-fr mw-list-item"><a href="https://fr.wikipedia.org/wiki/Radio_intelligente" title="Radio intelligente – French" lang="fr" hreflang="fr" data-title="Radio intelligente" data-language-autonym="Français" data-language-local-name="French" class="interlanguage-link-target"><span>Français</span></a></li><li class="interlanguage-link interwiki-ko mw-list-item"><a href="https://ko.wikipedia.org/wiki/%EC%9D%B8%EC%A7%80_%EB%AC%B4%EC%84%A0" title="인지 무선 – Korean" lang="ko" hreflang="ko" data-title="인지 무선" data-language-autonym="한국어" data-language-local-name="Korean" class="interlanguage-link-target"><span>한국어</span></a></li><li class="interlanguage-link interwiki-ja mw-list-item"><a href="https://ja.wikipedia.org/wiki/%E3%82%B3%E3%82%B0%E3%83%8B%E3%83%86%E3%82%A3%E3%83%96%E7%84%A1%E7%B7%9A" title="コグニティブ無線 – Japanese" lang="ja" hreflang="ja" data-title="コグニティブ無線" data-language-autonym="日本語" data-language-local-name="Japanese" class="interlanguage-link-target"><span>日本語</span></a></li><li class="interlanguage-link interwiki-pt mw-list-item"><a href="https://pt.wikipedia.org/wiki/R%C3%A1dio_cognitivo" title="Rádio cognitivo – Portuguese" lang="pt" hreflang="pt" data-title="Rádio cognitivo" data-language-autonym="Português" data-language-local-name="Portuguese" class="interlanguage-link-target"><span>Português</span></a></li><li class="interlanguage-link interwiki-ru mw-list-item"><a href="https://ru.wikipedia.org/wiki/%D0%9A%D0%BE%D0%B3%D0%BD%D0%B8%D1%82%D0%B8%D0%B2%D0%BD%D0%BE%D0%B5_%D1%80%D0%B0%D0%B4%D0%B8%D0%BE" title="Когнитивное радио – Russian" lang="ru" hreflang="ru" data-title="Когнитивное радио" data-language-autonym="Русский" data-language-local-name="Russian" class="interlanguage-link-target"><span>Русский</span></a></li><li class="interlanguage-link interwiki-sr mw-list-item"><a href="https://sr.wikipedia.org/wiki/%D0%9A%D0%BE%D0%B3%D0%BD%D0%B8%D1%82%D0%B8%D0%B2%D0%BD%D0%B8_%D1%80%D0%B0%D0%B4%D0%B8%D0%BE" title="Когнитивни радио – Serbian" lang="sr" hreflang="sr" data-title="Когнитивни радио" data-language-autonym="Српски / srpski" data-language-local-name="Serbian" class="interlanguage-link-target"><span>Српски / srpski</span></a></li><li class="interlanguage-link interwiki-tr mw-list-item"><a href="https://tr.wikipedia.org/wiki/Kavramsal_radyo" title="Kavramsal radyo – Turkish" lang="tr" hreflang="tr" data-title="Kavramsal radyo" data-language-autonym="Türkçe" data-language-local-name="Turkish" class="interlanguage-link-target"><span>Türkçe</span></a></li><li class="interlanguage-link interwiki-zh mw-list-item"><a href="https://zh.wikipedia.org/wiki/%E8%AE%A4%E7%9F%A5%E6%97%A0%E7%BA%BF%E7%94%B5" title="认知无线电 – Chinese" lang="zh" hreflang="zh" data-title="认知无线电" data-language-autonym="中文" data-language-local-name="Chinese" class="interlanguage-link-target"><span>中文</span></a></li> </ul> <div class="after-portlet after-portlet-lang"><span class="wb-langlinks-edit wb-langlinks-link"><a href="https://www.wikidata.org/wiki/Special:EntityPage/Q3235733#sitelinks-wikipedia" title="Edit interlanguage links" class="wbc-editpage">Edit links</a></span></div> </div> </div> </div> </header> <div class="vector-page-toolbar"> <div class="vector-page-toolbar-container"> <div id="left-navigation"> <nav aria-label="Namespaces"> <div id="p-associated-pages" class="vector-menu vector-menu-tabs mw-portlet mw-portlet-associated-pages" > <div class="vector-menu-content"> <ul class="vector-menu-content-list"> <li id="ca-nstab-main" class="selected vector-tab-noicon mw-list-item"><a href="/wiki/Cognitive_radio" title="View the content page [c]" accesskey="c"><span>Article</span></a></li><li id="ca-talk" class="vector-tab-noicon mw-list-item"><a href="/wiki/Talk:Cognitive_radio" rel="discussion" title="Discuss improvements to the content page [t]" accesskey="t"><span>Talk</span></a></li> </ul> </div> </div> <div id="vector-variants-dropdown" class="vector-dropdown emptyPortlet" > <input type="checkbox" id="vector-variants-dropdown-checkbox" role="button" aria-haspopup="true" data-event-name="ui.dropdown-vector-variants-dropdown" class="vector-dropdown-checkbox " aria-label="Change language variant" > <label id="vector-variants-dropdown-label" for="vector-variants-dropdown-checkbox" class="vector-dropdown-label cdx-button cdx-button--fake-button cdx-button--fake-button--enabled cdx-button--weight-quiet" aria-hidden="true" ><span class="vector-dropdown-label-text">English</span> </label> <div class="vector-dropdown-content"> <div id="p-variants" class="vector-menu mw-portlet mw-portlet-variants emptyPortlet" > <div class="vector-menu-content"> <ul class="vector-menu-content-list"> </ul> </div> </div> </div> </div> </nav> </div> <div id="right-navigation" class="vector-collapsible"> <nav aria-label="Views"> <div id="p-views" class="vector-menu vector-menu-tabs mw-portlet mw-portlet-views" > <div class="vector-menu-content"> <ul class="vector-menu-content-list"> <li id="ca-view" class="selected vector-tab-noicon mw-list-item"><a href="/wiki/Cognitive_radio"><span>Read</span></a></li><li id="ca-edit" class="vector-tab-noicon mw-list-item"><a href="/w/index.php?title=Cognitive_radio&action=edit" title="Edit this page [e]" accesskey="e"><span>Edit</span></a></li><li id="ca-history" class="vector-tab-noicon mw-list-item"><a href="/w/index.php?title=Cognitive_radio&action=history" title="Past revisions of this page [h]" accesskey="h"><span>View history</span></a></li> </ul> </div> </div> </nav> <nav class="vector-page-tools-landmark" aria-label="Page tools"> <div id="vector-page-tools-dropdown" class="vector-dropdown vector-page-tools-dropdown" > <input type="checkbox" id="vector-page-tools-dropdown-checkbox" role="button" aria-haspopup="true" data-event-name="ui.dropdown-vector-page-tools-dropdown" class="vector-dropdown-checkbox " aria-label="Tools" > <label id="vector-page-tools-dropdown-label" for="vector-page-tools-dropdown-checkbox" class="vector-dropdown-label cdx-button cdx-button--fake-button cdx-button--fake-button--enabled cdx-button--weight-quiet" aria-hidden="true" ><span class="vector-dropdown-label-text">Tools</span> </label> <div class="vector-dropdown-content"> <div id="vector-page-tools-unpinned-container" class="vector-unpinned-container"> <div id="vector-page-tools" class="vector-page-tools vector-pinnable-element"> <div class="vector-pinnable-header vector-page-tools-pinnable-header vector-pinnable-header-unpinned" data-feature-name="page-tools-pinned" data-pinnable-element-id="vector-page-tools" data-pinned-container-id="vector-page-tools-pinned-container" data-unpinned-container-id="vector-page-tools-unpinned-container" > <div class="vector-pinnable-header-label">Tools</div> <button class="vector-pinnable-header-toggle-button vector-pinnable-header-pin-button" data-event-name="pinnable-header.vector-page-tools.pin">move to sidebar</button> <button class="vector-pinnable-header-toggle-button vector-pinnable-header-unpin-button" data-event-name="pinnable-header.vector-page-tools.unpin">hide</button> </div> <div id="p-cactions" class="vector-menu mw-portlet mw-portlet-cactions emptyPortlet vector-has-collapsible-items" title="More options" > <div class="vector-menu-heading"> Actions </div> <div class="vector-menu-content"> <ul class="vector-menu-content-list"> <li id="ca-more-view" class="selected vector-more-collapsible-item mw-list-item"><a href="/wiki/Cognitive_radio"><span>Read</span></a></li><li id="ca-more-edit" class="vector-more-collapsible-item mw-list-item"><a href="/w/index.php?title=Cognitive_radio&action=edit" title="Edit this page [e]" accesskey="e"><span>Edit</span></a></li><li id="ca-more-history" class="vector-more-collapsible-item mw-list-item"><a href="/w/index.php?title=Cognitive_radio&action=history"><span>View history</span></a></li> </ul> </div> </div> <div id="p-tb" class="vector-menu mw-portlet mw-portlet-tb" > <div class="vector-menu-heading"> General </div> <div class="vector-menu-content"> <ul class="vector-menu-content-list"> <li id="t-whatlinkshere" class="mw-list-item"><a href="/wiki/Special:WhatLinksHere/Cognitive_radio" title="List of all English Wikipedia pages containing links to this page [j]" accesskey="j"><span>What links here</span></a></li><li id="t-recentchangeslinked" class="mw-list-item"><a href="/wiki/Special:RecentChangesLinked/Cognitive_radio" rel="nofollow" title="Recent changes in pages linked from this page [k]" accesskey="k"><span>Related changes</span></a></li><li id="t-upload" class="mw-list-item"><a href="/wiki/Wikipedia:File_Upload_Wizard" title="Upload files [u]" accesskey="u"><span>Upload file</span></a></li><li id="t-specialpages" class="mw-list-item"><a href="/wiki/Special:SpecialPages" title="A list of all special pages [q]" accesskey="q"><span>Special pages</span></a></li><li id="t-permalink" class="mw-list-item"><a href="/w/index.php?title=Cognitive_radio&oldid=1260832972" title="Permanent link to this revision of this page"><span>Permanent link</span></a></li><li id="t-info" class="mw-list-item"><a href="/w/index.php?title=Cognitive_radio&action=info" title="More information about this page"><span>Page information</span></a></li><li id="t-cite" class="mw-list-item"><a href="/w/index.php?title=Special:CiteThisPage&page=Cognitive_radio&id=1260832972&wpFormIdentifier=titleform" title="Information on how to cite this page"><span>Cite this page</span></a></li><li id="t-urlshortener" class="mw-list-item"><a href="/w/index.php?title=Special:UrlShortener&url=https%3A%2F%2Fen.wikipedia.org%2Fwiki%2FCognitive_radio"><span>Get shortened URL</span></a></li><li id="t-urlshortener-qrcode" class="mw-list-item"><a href="/w/index.php?title=Special:QrCode&url=https%3A%2F%2Fen.wikipedia.org%2Fwiki%2FCognitive_radio"><span>Download QR code</span></a></li> </ul> </div> </div> <div id="p-coll-print_export" class="vector-menu mw-portlet mw-portlet-coll-print_export" > <div class="vector-menu-heading"> Print/export </div> <div class="vector-menu-content"> <ul class="vector-menu-content-list"> <li id="coll-download-as-rl" class="mw-list-item"><a href="/w/index.php?title=Special:DownloadAsPdf&page=Cognitive_radio&action=show-download-screen" title="Download this page as a PDF file"><span>Download as PDF</span></a></li><li id="t-print" class="mw-list-item"><a href="/w/index.php?title=Cognitive_radio&printable=yes" title="Printable version of this page [p]" accesskey="p"><span>Printable version</span></a></li> </ul> </div> </div> <div id="p-wikibase-otherprojects" class="vector-menu mw-portlet mw-portlet-wikibase-otherprojects" > <div class="vector-menu-heading"> In other projects </div> <div class="vector-menu-content"> <ul class="vector-menu-content-list"> <li id="t-wikibase" class="wb-otherproject-link wb-otherproject-wikibase-dataitem mw-list-item"><a href="https://www.wikidata.org/wiki/Special:EntityPage/Q3235733" title="Structured data on this page hosted by Wikidata [g]" accesskey="g"><span>Wikidata item</span></a></li> </ul> </div> </div> </div> </div> </div> </div> </nav> </div> </div> </div> <div class="vector-column-end"> <div class="vector-sticky-pinned-container"> <nav class="vector-page-tools-landmark" aria-label="Page tools"> <div id="vector-page-tools-pinned-container" class="vector-pinned-container"> </div> </nav> <nav class="vector-appearance-landmark" aria-label="Appearance"> <div id="vector-appearance-pinned-container" class="vector-pinned-container"> <div id="vector-appearance" class="vector-appearance vector-pinnable-element"> <div class="vector-pinnable-header vector-appearance-pinnable-header vector-pinnable-header-pinned" data-feature-name="appearance-pinned" data-pinnable-element-id="vector-appearance" data-pinned-container-id="vector-appearance-pinned-container" data-unpinned-container-id="vector-appearance-unpinned-container" > <div class="vector-pinnable-header-label">Appearance</div> <button class="vector-pinnable-header-toggle-button vector-pinnable-header-pin-button" data-event-name="pinnable-header.vector-appearance.pin">move to sidebar</button> <button class="vector-pinnable-header-toggle-button vector-pinnable-header-unpin-button" data-event-name="pinnable-header.vector-appearance.unpin">hide</button> </div> </div> </div> </nav> </div> </div> <div id="bodyContent" class="vector-body" aria-labelledby="firstHeading" data-mw-ve-target-container> <div class="vector-body-before-content"> <div class="mw-indicators"> </div> <div id="siteSub" class="noprint">From Wikipedia, the free encyclopedia</div> </div> <div id="contentSub"><div id="mw-content-subtitle"></div></div> <div id="mw-content-text" class="mw-body-content"><div class="mw-content-ltr mw-parser-output" lang="en" dir="ltr"><div class="shortdescription nomobile noexcerpt noprint searchaux" style="display:none">Dynamically programmable radio</div> <p> A <b>cognitive radio</b> (<b>CR</b>) is a <a href="/wiki/Radio" title="Radio">radio</a> that can be programmed and configured dynamically to use the best <a href="/wiki/List_of_WLAN_channels" title="List of WLAN channels">channels</a> in its vicinity to avoid user interference and congestion. Such a radio automatically detects available channels, then accordingly changes its <a href="/wiki/Transmission_(telecommunications)" class="mw-redirect" title="Transmission (telecommunications)">transmission</a> or <a href="/wiki/Telecommunication" class="mw-redirect" title="Telecommunication">reception</a> parameters to allow more concurrent <a href="/wiki/Wireless_communications" class="mw-redirect" title="Wireless communications">wireless communications</a> in a given band at one location. This process is a form of <a href="/wiki/Dynamic_spectrum_management" title="Dynamic spectrum management">dynamic spectrum management</a>. </p> <meta property="mw:PageProp/toc" /> <div class="mw-heading mw-heading2"><h2 id="Description">Description</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Cognitive_radio&action=edit&section=1" title="Edit section: Description"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <p>In response to the operator's commands, the cognitive engine is capable of configuring radio-system parameters. These parameters include "<a href="/wiki/Waveform" title="Waveform">waveform</a>, protocol, operating frequency, and networking". This functions as an autonomous unit in the communications environment, exchanging information about the environment with the networks it accesses and other cognitive radios (CRs). A CR "monitors its own performance continuously", in addition to "reading the radio's outputs"; it then uses this information to "determine the <a href="/wiki/Radio_frequency" title="Radio frequency">RF</a> environment, channel conditions, link performance, etc.", and adjusts the "radio's settings to deliver the required quality of service subject to an appropriate combination of user requirements, operational limitations, and regulatory constraints". </p><p>Some "smart radio" proposals combine <a href="/wiki/Wireless_mesh_network" title="Wireless mesh network">wireless mesh network</a>—dynamically changing the path messages take between two given nodes using <a href="/wiki/Cooperative_diversity" title="Cooperative diversity">cooperative diversity</a>; cognitive radio—dynamically changing the frequency band used by messages between two consecutive nodes on the path; and <a href="/wiki/Software-defined_radio" title="Software-defined radio">software-defined radio</a>—dynamically changing the protocol used by message between two consecutive nodes. </p> <div class="mw-heading mw-heading2"><h2 id="History">History</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Cognitive_radio&action=edit&section=2" title="Edit section: History"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <p>The concept of <a href="/wiki/Cognition" title="Cognition">cognitive</a> radio was first proposed by Joseph Mitola III in a seminar at <a href="/wiki/KTH_Royal_Institute_of_Technology" title="KTH Royal Institute of Technology">KTH Royal Institute of Technology</a> in Stockholm in 1998 and published in an article by Mitola and Gerald Q. Maguire, Jr. in 1999. It was a novel approach in wireless communications, which Mitola later described as: </p> <blockquote><p>The point in which wireless <a href="/wiki/Personal_digital_assistant" title="Personal digital assistant">personal digital assistants</a> (PDAs) and the related networks are sufficiently computationally intelligent about radio resources and related computer-to-computer communications to detect user communications needs as a function of use context, and to provide radio resources and wireless services most appropriate to those needs. </p><p><sup id="cite_ref-mitola_dissertation_1-0" class="reference"><a href="#cite_note-mitola_dissertation-1"><span class="cite-bracket">[</span>1<span class="cite-bracket">]</span></a></sup> </p> </blockquote> <p>Cognitive radio is considered as a goal towards which a <a href="/wiki/Software-defined_radio" title="Software-defined radio">software-defined radio</a> platform should evolve: a fully reconfigurable wireless transceiver which automatically adapts its communication parameters to network and user demands. </p><p>Traditional regulatory structures have been built for an analog model and are not optimized for cognitive radio. Regulatory bodies in the world (including the <a href="/wiki/Federal_Communications_Commission" title="Federal Communications Commission">Federal Communications Commission</a> in the United States and <a href="/wiki/Ofcom" title="Ofcom">Ofcom</a> in the United Kingdom) as well as different independent measurement campaigns found that most <a href="/wiki/Radio_frequency" title="Radio frequency">radio frequency</a> spectrum was inefficiently utilized.<sup id="cite_ref-V._Valenta_et_al.,_Survey_on_spectrum_utilization_in_Europe:_Measurements,_analyses_and_observations_2-0" class="reference"><a href="#cite_note-V._Valenta_et_al.,_Survey_on_spectrum_utilization_in_Europe:_Measurements,_analyses_and_observations-2"><span class="cite-bracket">[</span>2<span class="cite-bracket">]</span></a></sup> <a href="/wiki/Cellular_network" title="Cellular network">Cellular network</a> bands are overloaded in most parts of the world, but other frequency bands (such as military, <a href="/wiki/Amateur_radio" title="Amateur radio">amateur radio</a> and <a href="/wiki/Paging_(telecommunications)" class="mw-redirect" title="Paging (telecommunications)">paging</a> frequencies) are insufficiently utilized. Independent studies performed in some countries confirmed that observation, and concluded that spectrum utilization depends on time and place. Moreover, fixed spectrum allocation prevents rarely used frequencies (those assigned to specific services) from being used, even when any unlicensed users would not cause noticeable interference to the assigned service. Regulatory bodies in the world have been considering whether to allow unlicensed users in licensed bands if they would not cause any interference to licensed users. These initiatives have focused cognitive-radio research on <a href="/wiki/Dynamic_spectrum_management" title="Dynamic spectrum management">dynamic spectrum access</a>. </p><p>The first cognitive radio wireless regional area network standard, <a href="/wiki/IEEE_802.22" title="IEEE 802.22">IEEE 802.22</a>, was developed by IEEE 802 LAN/MAN Standard Committee (LMSC)<sup id="cite_ref-3" class="reference"><a href="#cite_note-3"><span class="cite-bracket">[</span>3<span class="cite-bracket">]</span></a></sup> and published in 2011. This standard uses geolocation and spectrum sensing for spectral awareness. Geolocation combines with a <a href="/wiki/TV_White_Space_Database" title="TV White Space Database">database of licensed transmitters</a> in the area to identify available channels for use by the cognitive radio network. Spectrum sensing observes the spectrum and identifies occupied channels. IEEE 802.22 was designed to utilize the unused frequencies or fragments of time in a location. This white space is unused television channels in the geolocated areas. However, cognitive radio cannot occupy the same unused space all the time. As spectrum availability changes, the network adapts to prevent interference with licensed transmissions.<sup id="cite_ref-4" class="reference"><a href="#cite_note-4"><span class="cite-bracket">[</span>4<span class="cite-bracket">]</span></a></sup> </p> <div class="mw-heading mw-heading2"><h2 id="Terminology">Terminology</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Cognitive_radio&action=edit&section=3" title="Edit section: Terminology"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <p>Depending on transmission and reception parameters, there are two main types of cognitive radio: </p> <ul><li><i>Full Cognitive Radio</i> (Mitola radio), in which every possible parameter observable by a wireless node (or network) is considered.<sup id="cite_ref-5" class="reference"><a href="#cite_note-5"><span class="cite-bracket">[</span>5<span class="cite-bracket">]</span></a></sup></li> <li><i>Spectrum-Sensing Cognitive Radio</i>, in which only the radio-frequency spectrum is considered.</li></ul> <p>Other types are dependent on parts of the spectrum available for cognitive radio: </p> <ul><li><i>Licensed-Band Cognitive Radio</i>, capable of using bands assigned to licensed users (except for unlicensed bands, such as the <a href="/wiki/U-NII" class="mw-redirect" title="U-NII">U-NII</a> band or the <a href="/wiki/ISM_band" class="mw-redirect" title="ISM band">ISM band</a>). The <a href="/wiki/IEEE_802.22" title="IEEE 802.22">IEEE 802.22</a> working group is developing a standard for wireless regional area network (WRAN), which will operate on unused television channels, also known as TV <a href="/wiki/White_spaces_(radio)" title="White spaces (radio)">white spaces</a>.<sup id="cite_ref-6" class="reference"><a href="#cite_note-6"><span class="cite-bracket">[</span>6<span class="cite-bracket">]</span></a></sup><sup id="cite_ref-Carl2009_7-0" class="reference"><a href="#cite_note-Carl2009-7"><span class="cite-bracket">[</span>7<span class="cite-bracket">]</span></a></sup></li> <li><i>Unlicensed-Band Cognitive Radio</i>, which can only utilize unlicensed parts of the radio frequency (RF) spectrum.<sup class="noprint Inline-Template Template-Fact" style="white-space:nowrap;">[<i><a href="/wiki/Wikipedia:Citation_needed" title="Wikipedia:Citation needed"><span title="This claim needs references to reliable sources. (January 2009)">citation needed</span></a></i>]</sup> One such system is described in the <a href="/wiki/IEEE_802.15" title="IEEE 802.15">IEEE 802.15</a> Task Group 2 specifications,<sup id="cite_ref-8" class="reference"><a href="#cite_note-8"><span class="cite-bracket">[</span>8<span class="cite-bracket">]</span></a></sup> which focus on the coexistence of <a href="/wiki/IEEE_802.11" title="IEEE 802.11">IEEE 802.11</a> and <a href="/wiki/Bluetooth" title="Bluetooth">Bluetooth</a>.<sup class="noprint Inline-Template Template-Fact" style="white-space:nowrap;">[<i><a href="/wiki/Wikipedia:Citation_needed" title="Wikipedia:Citation needed"><span title="This claim needs references to reliable sources. (January 2009)">citation needed</span></a></i>]</sup></li> <li><i>Spectrum mobility</i>: Process by which a cognitive-radio user changes its frequency of operation. Cognitive-radio networks aim to use the spectrum in a dynamic manner by allowing radio terminals to operate in the best available frequency band, maintaining seamless communication requirements during transitions to better spectrum.</li> <li><i>Spectrum sharing<sup id="cite_ref-ieeexplore.ieee.org_9-0" class="reference"><a href="#cite_note-ieeexplore.ieee.org-9"><span class="cite-bracket">[</span>9<span class="cite-bracket">]</span></a></sup></i>: Spectrum sharing cognitive radio networks allow cognitive radio users to share the spectrum bands of the licensed-band users. However, the cognitive radio users have to restrict their transmit power so that the interference caused to the licensed-band users is kept below a certain threshold.</li> <li><i>Sensing-based Spectrum sharing</i>:<sup id="cite_ref-10" class="reference"><a href="#cite_note-10"><span class="cite-bracket">[</span>10<span class="cite-bracket">]</span></a></sup> In sensing-based spectrum sharing cognitive radio networks, cognitive radio users first listen to the spectrum allocated to the licensed users to detect the state of the licensed users. Based on the detection results, cognitive radio users decide their transmission strategies. If the licensed users are not using the bands, cognitive radio users will transmit over those bands. If the licensed users are using the bands, cognitive radio users share the spectrum bands with the licensed users by restricting their transmit power.</li> <li><i>Database-enabled Spectrum Sharing</i>,<sup id="cite_ref-11" class="reference"><a href="#cite_note-11"><span class="cite-bracket">[</span>11<span class="cite-bracket">]</span></a></sup><sup id="cite_ref-12" class="reference"><a href="#cite_note-12"><span class="cite-bracket">[</span>12<span class="cite-bracket">]</span></a></sup>,:<sup id="cite_ref-13" class="reference"><a href="#cite_note-13"><span class="cite-bracket">[</span>13<span class="cite-bracket">]</span></a></sup> In this modality of spectrum sharing, cognitive radio users are required to access a <a href="/wiki/TV_White_Space_Database" title="TV White Space Database">white space database</a> prior to be allowed, or denied, access to the shared spectrum. The white space database contain algorithms, mathematical models and local regulations to predict the spectrum utilization in a geographical area and to infer on the risk of interference posed to incumbent services by a cognitive radio user accessing the shared spectrum. If the <a href="/wiki/TV_White_Space_Database" title="TV White Space Database">white space database</a> judges that destructive interference to incumbents will happen, the cognitive radio user is denied access to the shared spectrum.</li></ul> <div class="mw-heading mw-heading2"><h2 id="Technology">Technology</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Cognitive_radio&action=edit&section=4" title="Edit section: Technology"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <p>Although cognitive radio was initially thought of as a <a href="/wiki/Software-defined_radio" title="Software-defined radio">software-defined radio</a> extension (full cognitive radio), most research work focuses on spectrum-sensing cognitive radio (particularly in the <a href="/wiki/TV" class="mw-redirect" title="TV">TV</a> bands). The chief problem in spectrum-sensing cognitive radio is designing high-quality spectrum-sensing devices and algorithms for exchanging spectrum-sensing data between nodes. It has been shown that a simple energy detector cannot guarantee the accurate detection of signal presence,<sup id="cite_ref-14" class="reference"><a href="#cite_note-14"><span class="cite-bracket">[</span>14<span class="cite-bracket">]</span></a></sup> calling for more sophisticated spectrum sensing techniques and requiring information about spectrum sensing to be regularly exchanged between nodes. Increasing the number of cooperating sensing nodes decreases the probability of false detection.<sup id="cite_ref-15" class="reference"><a href="#cite_note-15"><span class="cite-bracket">[</span>15<span class="cite-bracket">]</span></a></sup> </p><p>Filling free RF bands adaptively, using <a href="/wiki/OFDMA" class="mw-redirect" title="OFDMA">OFDMA</a>, is a possible approach. Timo A. Weiss and Friedrich K. Jondral of the <a href="/wiki/University_of_Karlsruhe" class="mw-redirect" title="University of Karlsruhe">University of Karlsruhe</a> proposed a <a href="/wiki/Spectrum_pooling" title="Spectrum pooling">spectrum pooling</a> system, in which free bands (sensed by nodes) were immediately filled by <a href="/wiki/OFDMA" class="mw-redirect" title="OFDMA">OFDMA</a> subbands. Applications of spectrum-sensing cognitive radio include <a href="/wiki/Professional_Mobile_Radio" class="mw-redirect" title="Professional Mobile Radio">emergency-network</a> and <a href="/wiki/Wireless_LAN" title="Wireless LAN">WLAN</a> higher <a href="/wiki/Throughput" class="mw-redirect" title="Throughput">throughput</a> and <a href="/wiki/Transmission_(telecommunications)" class="mw-redirect" title="Transmission (telecommunications)">transmission</a>-distance extensions. The evolution of cognitive radio toward <a href="/wiki/Cognitive_network" title="Cognitive network">cognitive networks</a> is underway; the concept of cognitive networks is to intelligently organize a network of cognitive radios. </p> <div class="mw-heading mw-heading3"><h3 id="Functions"><span class="anchor" id="Main_functions"></span>Functions</h3><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Cognitive_radio&action=edit&section=5" title="Edit section: Functions"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <p>The main functions of cognitive radios are:<sup id="cite_ref-16" class="reference"><a href="#cite_note-16"><span class="cite-bracket">[</span>16<span class="cite-bracket">]</span></a></sup><sup id="cite_ref-17" class="reference"><a href="#cite_note-17"><span class="cite-bracket">[</span>17<span class="cite-bracket">]</span></a></sup> </p> <ul><li><i>Power Control</i>: Power control<sup id="cite_ref-18" class="reference"><a href="#cite_note-18"><span class="cite-bracket">[</span>18<span class="cite-bracket">]</span></a></sup> is usually used for spectrum sharing CR systems to maximize the capacity of secondary users with interference power constraints to protect the primary users.</li> <li><i>Spectrum sensing</i>: Detecting unused spectrum and sharing it, without harmful interference to other users; an important requirement of the cognitive-radio network is to sense empty spectrum. Detecting primary users is the most efficient way to detect empty spectrum. Spectrum-sensing techniques may be grouped into three categories: <ul><li><i>Transmitter detection</i>: Cognitive radios must have the capability to determine if a signal from a primary transmitter is locally present in a certain spectrum. There are several proposed approaches to transmitter detection: <ul><li><a href="/wiki/Matched_filter" title="Matched filter">Matched filter</a> detection</li> <li>Energy detection: Energy detection is a spectrum sensing method that detects the presence/absence of a signal just by measuring the received signal power.<sup id="cite_ref-dx.doi.org_19-0" class="reference"><a href="#cite_note-dx.doi.org-19"><span class="cite-bracket">[</span>19<span class="cite-bracket">]</span></a></sup> This signal detection approach is quite easy and convenient for practical implementation. To implement energy detector, however, noise variance information is required. It has been shown that an imperfect knowledge of the noise power (noise uncertainty) may lead to the phenomenon of the <a href="/wiki/Signal-to-noise_ratio" title="Signal-to-noise ratio">SNR</a> wall, which is a SNR level below which the energy detector can not reliably detect any transmitted signal even increasing the observation time.<sup id="cite_ref-20" class="reference"><a href="#cite_note-20"><span class="cite-bracket">[</span>20<span class="cite-bracket">]</span></a></sup> It<sup id="cite_ref-margiochi_21-0" class="reference"><a href="#cite_note-margiochi-21"><span class="cite-bracket">[</span>21<span class="cite-bracket">]</span></a></sup> has also been shown that the SNR wall is not caused by the presence of a noise uncertainty itself, but by an insufficient refinement of the noise power estimation while the observation time increases.</li> <li><a href="/wiki/Cyclostationary_process" title="Cyclostationary process">Cyclostationary</a>-feature detection: These type of spectrum sensing algorithms are motivated because most man-made communication signals, such as <a href="/wiki/Phase-shift_keying" title="Phase-shift keying">BPSK</a>, <a href="/wiki/Phase-shift_keying" title="Phase-shift keying">QPSK</a>, <a href="/wiki/Amplitude_modulation" title="Amplitude modulation">AM</a>, <a href="/wiki/Orthogonal_frequency-division_multiplexing" title="Orthogonal frequency-division multiplexing">OFDM</a>, etc. exhibit cyclostationary behavior.<sup id="cite_ref-22" class="reference"><a href="#cite_note-22"><span class="cite-bracket">[</span>22<span class="cite-bracket">]</span></a></sup> However, noise signals (typically <a href="/wiki/White_noise" title="White noise">white noise</a>) do not exhibit cyclostationary behavior. These detectors are robust against noise variance uncertainty. The aim of such detectors is to exploit the cyclostationary nature of man-made communication signals buried in noise. Their main decision parameter is comparing the non zero values obtained by CSD of the primary signal.<sup id="cite_ref-cse.wustl.edu_23-0" class="reference"><a href="#cite_note-cse.wustl.edu-23"><span class="cite-bracket">[</span>23<span class="cite-bracket">]</span></a></sup> Cyclostationary detectors can be either single cycle or multicycle cyclostationary.</li></ul></li></ul></li> <li><i>Wideband spectrum sensing</i>: refers to spectrum sensing over large spectral bandwidth, typically hundreds of MHz or even several GHz. Since current ADC technology cannot afford the high sampling rate with high resolution, it requires revolutional techniques, e.g., compressive sensing and sub-Nyquist sampling.<sup id="cite_ref-24" class="reference"><a href="#cite_note-24"><span class="cite-bracket">[</span>24<span class="cite-bracket">]</span></a></sup> <ul><li><i>Cooperative detection</i>: Refers to spectrum-sensing methods where information from multiple cognitive-radio users is incorporated for primary-user detection<sup id="cite_ref-25" class="reference"><a href="#cite_note-25"><span class="cite-bracket">[</span>25<span class="cite-bracket">]</span></a></sup></li> <li><i>Interference-based detection</i></li></ul></li> <li><i>Null-space based CR</i>: With the aid of multiple antennas, CR detects the null-space of the primary-user and then transmits within the null-space, such that its subsequent transmission causes less interference to the primary-user</li> <li><i>Spectrum management</i>: Capturing the best available spectrum to meet user communication requirements, while not creating undue interference to other (primary) users. Cognitive radios should decide on the best spectrum band (of all bands available) to meet <a href="/wiki/Quality_of_service" title="Quality of service">quality of service</a> requirements; therefore, spectrum-management functions are required for cognitive radios. Spectrum-management functions are classified as: <ul><li><i>Spectrum analysis</i></li> <li><i>Spectrum decision</i><sup id="cite_ref-26" class="reference"><a href="#cite_note-26"><span class="cite-bracket">[</span>26<span class="cite-bracket">]</span></a></sup><sup id="cite_ref-27" class="reference"><a href="#cite_note-27"><span class="cite-bracket">[</span>27<span class="cite-bracket">]</span></a></sup></li></ul></li></ul> <p>The practical implementation of spectrum-management functions is a complex and multifaceted issue, since it must address a variety of technical and legal requirements. An example of the former is choosing an appropriate sensing threshold to detect other users, while the latter is exemplified by the need to meet the rules and regulations set out for radio spectrum access in international (ITU radio regulations) and national (telecommunications law) legislation. Artificial Intelligence based algorithms algorithm for dynamic spectrum allocation and interference management in order to reduce harmful interference to other services and networks will be a key technology enabler towards 6G. This will pave the way for more flexibility in the management and regulation of the radioelectric spectrum.<sup id="cite_ref-28" class="reference"><a href="#cite_note-28"><span class="cite-bracket">[</span>28<span class="cite-bracket">]</span></a></sup><sup id="cite_ref-29" class="reference"><a href="#cite_note-29"><span class="cite-bracket">[</span>29<span class="cite-bracket">]</span></a></sup> </p> <div class="mw-heading mw-heading3"><h3 id="Intelligent_antenna_(IA)"><span id="Intelligent_antenna_.28IA.29"></span>Intelligent antenna (IA)</h3><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Cognitive_radio&action=edit&section=6" title="Edit section: Intelligent antenna (IA)"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <p>An <a href="/wiki/Smart_antenna" title="Smart antenna">intelligent antenna (or smart antenna)</a> is an antenna technology that uses spatial beam-formation and spatial coding to cancel interference; however, applications are emerging for extension to intelligent multiple or cooperative-antenna arrays for application to complex communication environments. Cognitive radio, by comparison, allows user terminals to sense whether a portion of the spectrum is being used in order to share spectrum with neighbor users. The following table compares the two: </p> <table class="sortable wikitable"> <tbody><tr> <th>Point</th> <th>Cognitive radio (CR)</th> <th>Intelligent antenna (IA) </th></tr> <tr> <th>Principal goal </th> <td><a href="/wiki/Open_spectrum" title="Open spectrum">Open spectrum</a> sharing </td> <td>Ambient <a href="/wiki/Spatial_multiplexing" title="Spatial multiplexing">spatial reuse</a> </td></tr> <tr> <th>Interference processing </th> <td>Avoidance by spectrum sensing </td> <td>Cancellation by spatial <a href="/wiki/Precoding" title="Precoding">precoding</a>/post-coding </td></tr> <tr> <th>Key cost </th> <td>Spectrum sensing and multi-band RF </td> <td>Multiple- or cooperative-antenna arrays </td></tr> <tr> <th>Challenging algorithm </th> <td>Spectrum management tech </td> <td>Intelligent spatial <a href="/wiki/Beamforming" title="Beamforming">beamforming</a>/coding tech </td></tr> <tr> <th>Applied techniques </th> <td>Cognitive software radio </td> <td>Generalized <a href="/wiki/Dirty_paper_coding" title="Dirty paper coding">dirty paper coding</a> and <a href="/wiki/Distributed_source_coding#Wyner–Ziv_coding_–_lossy_distributed_coding" title="Distributed source coding">Wyner-Ziv coding</a> </td></tr> <tr> <th>Basement approach </th> <td>Orthogonal modulation </td> <td>Cellular based smaller cell </td></tr> <tr> <th>Competitive technology </th> <td><a href="/wiki/Ultra-wideband" title="Ultra-wideband">Ultra-wideband</a> for greater band utilization </td> <td><a href="/wiki/Sectorization" class="mw-redirect" title="Sectorization">Multi-sectoring</a> (3, 6, 9, so on) for higher spatial reuse </td></tr> <tr> <th>Summary </th> <td>Cognitive spectrum-sharing technology </td> <td>Intelligent spectrum reuse technology </td></tr></tbody></table> <p>Note that both techniques can be combined as illustrated in many contemporary transmission scenarios.<sup id="cite_ref-30" class="reference"><a href="#cite_note-30"><span class="cite-bracket">[</span>30<span class="cite-bracket">]</span></a></sup> </p><p><a href="/wiki/Cooperative_wireless_communications" class="mw-redirect" title="Cooperative wireless communications">Cooperative MIMO (CO-MIMO)</a> combines both techniques. </p> <div class="mw-heading mw-heading2"><h2 id="Applications"><span class="anchor" id="Practical_application"></span>Applications</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Cognitive_radio&action=edit&section=7" title="Edit section: Applications"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <p>Cognitive Radio (CR) can sense its environment and, without the intervention of the user, can adapt to the user's communications needs while conforming to <a href="/wiki/Federal_Communications_Commission" title="Federal Communications Commission">FCC</a> rules in the United States. In theory, the amount of spectrum is infinite; practically, for propagation and other reasons it is finite because of the desirability of certain spectrum portions. Assigned spectrum is far from being fully utilized, and efficient spectrum use is a growing concern; CR offers a solution to this problem. A CR can intelligently detect whether any portion of the spectrum is in use, and can temporarily use it without interfering with the transmissions of other users.<sup id="cite_ref-31" class="reference"><a href="#cite_note-31"><span class="cite-bracket">[</span>31<span class="cite-bracket">]</span></a></sup> According to Bruce Fette, "Some of the radio's other cognitive abilities include determining its location, sensing spectrum use by neighboring devices, changing frequency, adjusting output power or even altering transmission parameters and characteristics. All of these capabilities, and others yet to be realized, will provide wireless spectrum users with the ability to adapt to real-time spectrum conditions, offering regulators, licenses and the general public flexible, efficient and comprehensive use of the spectrum". </p><p>Examples of applications include: </p> <ul><li>The application of CR networks to emergency and public safety communications by utilizing white space<sup id="cite_ref-32" class="reference"><a href="#cite_note-32"><span class="cite-bracket">[</span>32<span class="cite-bracket">]</span></a></sup><sup id="cite_ref-33" class="reference"><a href="#cite_note-33"><span class="cite-bracket">[</span>33<span class="cite-bracket">]</span></a></sup></li> <li>The potential of CR networks for executing dynamic spectrum access (DSA)<sup id="cite_ref-34" class="reference"><a href="#cite_note-34"><span class="cite-bracket">[</span>34<span class="cite-bracket">]</span></a></sup><sup id="cite_ref-35" class="reference"><a href="#cite_note-35"><span class="cite-bracket">[</span>35<span class="cite-bracket">]</span></a></sup></li> <li>Application of CR networks to military action such as chemical biological radiological and nuclear attack detection and investigation, command control, obtaining information of battle damage evaluations, battlefield surveillance, intelligence assistance, and targeting.<sup id="cite_ref-36" class="reference"><a href="#cite_note-36"><span class="cite-bracket">[</span>36<span class="cite-bracket">]</span></a></sup></li> <li>They are also proven to be helpful in establishing Medical Body Area Networks<sup id="cite_ref-cse.wustl.edu_23-1" class="reference"><a href="#cite_note-cse.wustl.edu-23"><span class="cite-bracket">[</span>23<span class="cite-bracket">]</span></a></sup> which can be utilized in omnipresent patient monitoring that aids in immediately notifying the doctors regarding vital information of patients such as sugar level, blood pressure, blood oxygen and electrocardiogram (ECG), etc. This gives the additional advantage of reducing the risk of infections and also increases the patient's mobility.</li> <li>Cognitive radio is practical also to wireless sensor networks, where packet relaying can take place using primary and secondary queues to forward packets without delays and with minimum power consumption.<sup id="cite_ref-37" class="reference"><a href="#cite_note-37"><span class="cite-bracket">[</span>37<span class="cite-bracket">]</span></a></sup></li></ul> <div class="mw-heading mw-heading2"><h2 id="Simulation_of_CR_networks">Simulation of CR networks</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Cognitive_radio&action=edit&section=8" title="Edit section: Simulation of CR networks"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <p>At present, <a href="/wiki/Modeling_and_simulation" title="Modeling and simulation">modeling & simulation</a> is the only paradigm which allows the simulation of complex behavior in a given environment's cognitive radio networks. Network simulators like <a href="/wiki/OPNET" title="OPNET">OPNET</a>, <a href="/w/index.php?title=NetSim&action=edit&redlink=1" class="new" title="NetSim (page does not exist)">NetSim</a>, <a href="/wiki/MATLAB" title="MATLAB">MATLAB</a> and <a href="/wiki/Ns_(simulator)" title="Ns (simulator)">ns2</a> can be used to simulate a cognitive radio network. <b>CogNS</b><sup id="cite_ref-38" class="reference"><a href="#cite_note-38"><span class="cite-bracket">[</span>38<span class="cite-bracket">]</span></a></sup> is an open-source NS2-based simulation framework for cognitive radio networks. Areas of research using network simulators include: </p> <ol><li>Spectrum sensing & incumbent detection</li> <li>Spectrum allocation</li> <li>Measurement and/or modeling of spectrum usage<sup id="cite_ref-simulationCR1_39-0" class="reference"><a href="#cite_note-simulationCR1-39"><span class="cite-bracket">[</span>39<span class="cite-bracket">]</span></a></sup><sup id="cite_ref-simulationCR2_40-0" class="reference"><a href="#cite_note-simulationCR2-40"><span class="cite-bracket">[</span>40<span class="cite-bracket">]</span></a></sup></li> <li>Efficiency of spectrum utilization<sup id="cite_ref-simulationCR1_39-1" class="reference"><a href="#cite_note-simulationCR1-39"><span class="cite-bracket">[</span>39<span class="cite-bracket">]</span></a></sup><sup id="cite_ref-simulationCR2_40-1" class="reference"><a href="#cite_note-simulationCR2-40"><span class="cite-bracket">[</span>40<span class="cite-bracket">]</span></a></sup></li></ol> <p>Network Simulator 3 (ns-3) is also a viable option for simulating CR.<sup id="cite_ref-A._Shattal,_A._Wisniewska_2018_41-0" class="reference"><a href="#cite_note-A._Shattal,_A._Wisniewska_2018-41"><span class="cite-bracket">[</span>41<span class="cite-bracket">]</span></a></sup> ns-3 can be also used to emulate and experiment CR networks with the aid from commodity hardware like Atheros WiFi devices.<sup id="cite_ref-A._Shattal,_A._Wisniewska_2018_41-1" class="reference"><a href="#cite_note-A._Shattal,_A._Wisniewska_2018-41"><span class="cite-bracket">[</span>41<span class="cite-bracket">]</span></a></sup> </p> <div class="mw-heading mw-heading2"><h2 id="Future_plans"><span class="anchor" id="The_future_of_CR"></span>Future plans</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Cognitive_radio&action=edit&section=9" title="Edit section: Future plans"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <p>The success of the unlicensed band in accommodating a range of wireless devices and services has led the FCC to consider opening further bands for unlicensed use. In contrast, the licensed bands are underutilized due to static frequency allocation. Realizing that CR technology has the potential to exploit the inefficiently utilized licensed bands without causing interference to incumbent users, the FCC released a Notice of Proposed Rule Making which would allow unlicensed radios to operate in the TV-broadcast bands. The <a href="/wiki/IEEE_802.22" title="IEEE 802.22">IEEE 802.22</a> working group, formed in November 2004, is tasked with defining the air-interface standard for wireless regional area networks (based on CR sensing) for the operation of unlicensed devices in the spectrum allocated to TV service.<sup id="cite_ref-42" class="reference"><a href="#cite_note-42"><span class="cite-bracket">[</span>42<span class="cite-bracket">]</span></a></sup> To comply with later FCC regulations on unlicensed utilization of TV spectrum, the IEEE 802.22 has defined interfaces to the mandatory <a href="/wiki/TV_White_Space_Database" title="TV White Space Database">TV White Space Database</a> in order to avoid interference to incumbent services.<sup id="cite_ref-43" class="reference"><a href="#cite_note-43"><span class="cite-bracket">[</span>43<span class="cite-bracket">]</span></a></sup> Although spectrum geolocation databases allow reducing the receiver complexity, and interference probability, for instance from sensing errors or hidden nodes, this comes at the cost of a lower spectrum utilization efficiency as the databases can not capture a fine-grained quantification of spectrum utilization and are not updated in real-time. Collaborative sensing, and distributed spectrum management based on artificial intelligence could contribute in the future towards a better balance between spectrum utilization efficiency and interference mitigation.<sup id="cite_ref-44" class="reference"><a href="#cite_note-44"><span class="cite-bracket">[</span>44<span class="cite-bracket">]</span></a></sup> </p> <div class="mw-heading mw-heading2"><h2 id="See_also">See also</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Cognitive_radio&action=edit&section=10" title="Edit section: See also"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <ul><li><a href="/wiki/Channel_allocation_schemes" title="Channel allocation schemes">Channel allocation schemes</a></li> <li><a href="/wiki/Channel-dependent_scheduling" class="mw-redirect" title="Channel-dependent scheduling">Channel-dependent scheduling</a></li> <li><a href="/wiki/Cognitive_network" title="Cognitive network">Cognitive network</a></li> <li><a href="/wiki/LTE_Advanced" title="LTE Advanced">LTE Advanced</a></li> <li><a href="/wiki/Network_Simulator" class="mw-redirect" title="Network Simulator">Network Simulator</a></li> <li><a href="/wiki/OFDMA" class="mw-redirect" title="OFDMA">OFDMA</a></li> <li><a href="/wiki/Radio_resource_management" title="Radio resource management">Radio resource management</a> (RRM)</li> <li><a href="/wiki/White_spaces_(radio)" title="White spaces (radio)">White spaces (radio)</a></li> <li><a href="/wiki/TV_White_Space_Database" title="TV White Space Database">White spaces (database)</a></li> <li><a href="/wiki/Software-defined_radio" title="Software-defined radio">Software-defined radio</a></li></ul> <div class="mw-heading mw-heading2"><h2 id="References">References</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Cognitive_radio&action=edit&section=11" title="Edit section: References"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <style data-mw-deduplicate="TemplateStyles:r1239543626">.mw-parser-output .reflist{margin-bottom:0.5em;list-style-type:decimal}@media screen{.mw-parser-output .reflist{font-size:90%}}.mw-parser-output .reflist .references{font-size:100%;margin-bottom:0;list-style-type:inherit}.mw-parser-output .reflist-columns-2{column-width:30em}.mw-parser-output .reflist-columns-3{column-width:25em}.mw-parser-output .reflist-columns{margin-top:0.3em}.mw-parser-output .reflist-columns ol{margin-top:0}.mw-parser-output .reflist-columns li{page-break-inside:avoid;break-inside:avoid-column}.mw-parser-output .reflist-upper-alpha{list-style-type:upper-alpha}.mw-parser-output .reflist-upper-roman{list-style-type:upper-roman}.mw-parser-output .reflist-lower-alpha{list-style-type:lower-alpha}.mw-parser-output .reflist-lower-greek{list-style-type:lower-greek}.mw-parser-output .reflist-lower-roman{list-style-type:lower-roman}</style><div class="reflist"> <div class="mw-references-wrap mw-references-columns"><ol class="references"> <li id="cite_note-mitola_dissertation-1"><span class="mw-cite-backlink"><b><a href="#cite_ref-mitola_dissertation_1-0">^</a></b></span> <span class="reference-text"><style data-mw-deduplicate="TemplateStyles:r1238218222">.mw-parser-output cite.citation{font-style:inherit;word-wrap:break-word}.mw-parser-output .citation q{quotes:"\"""\"""'""'"}.mw-parser-output .citation:target{background-color:rgba(0,127,255,0.133)}.mw-parser-output .id-lock-free.id-lock-free a{background:url("//upload.wikimedia.org/wikipedia/commons/6/65/Lock-green.svg")right 0.1em center/9px no-repeat}.mw-parser-output .id-lock-limited.id-lock-limited a,.mw-parser-output .id-lock-registration.id-lock-registration a{background:url("//upload.wikimedia.org/wikipedia/commons/d/d6/Lock-gray-alt-2.svg")right 0.1em center/9px no-repeat}.mw-parser-output .id-lock-subscription.id-lock-subscription a{background:url("//upload.wikimedia.org/wikipedia/commons/a/aa/Lock-red-alt-2.svg")right 0.1em center/9px no-repeat}.mw-parser-output .cs1-ws-icon a{background:url("//upload.wikimedia.org/wikipedia/commons/4/4c/Wikisource-logo.svg")right 0.1em center/12px no-repeat}body:not(.skin-timeless):not(.skin-minerva) .mw-parser-output .id-lock-free a,body:not(.skin-timeless):not(.skin-minerva) .mw-parser-output .id-lock-limited a,body:not(.skin-timeless):not(.skin-minerva) .mw-parser-output .id-lock-registration a,body:not(.skin-timeless):not(.skin-minerva) .mw-parser-output .id-lock-subscription a,body:not(.skin-timeless):not(.skin-minerva) .mw-parser-output .cs1-ws-icon a{background-size:contain;padding:0 1em 0 0}.mw-parser-output .cs1-code{color:inherit;background:inherit;border:none;padding:inherit}.mw-parser-output .cs1-hidden-error{display:none;color:var(--color-error,#d33)}.mw-parser-output .cs1-visible-error{color:var(--color-error,#d33)}.mw-parser-output .cs1-maint{display:none;color:#085;margin-left:0.3em}.mw-parser-output .cs1-kern-left{padding-left:0.2em}.mw-parser-output .cs1-kern-right{padding-right:0.2em}.mw-parser-output .citation .mw-selflink{font-weight:inherit}@media screen{.mw-parser-output .cs1-format{font-size:95%}html.skin-theme-clientpref-night .mw-parser-output .cs1-maint{color:#18911f}}@media screen and (prefers-color-scheme:dark){html.skin-theme-clientpref-os .mw-parser-output .cs1-maint{color:#18911f}}</style><cite id="CITEREFMitola2000" class="citation cs2">Mitola, Joseph (2000), <a rel="nofollow" class="external text" href="http://kth.diva-portal.org/smash/record.jsf?pid=diva2:8730">"Cognitive Radio – An Integrated Agent Architecture for Software Defined Radio"</a>, <i>Diva</i> (PhD dissertation), Kista, Sweden: <a href="/wiki/Royal_Institute_of_Technology" class="mw-redirect" title="Royal Institute of Technology">KTH Royal Institute of Technology</a>, <a href="/wiki/ISSN_(identifier)" class="mw-redirect" title="ISSN (identifier)">ISSN</a> <a rel="nofollow" class="external text" href="https://search.worldcat.org/issn/1403-5286">1403-5286</a></cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.genre=article&rft.jtitle=Diva&rft.atitle=Cognitive+Radio+%E2%80%93+An+Integrated+Agent+Architecture+for+Software+Defined+Radio&rft.date=2000&rft.issn=1403-5286&rft.aulast=Mitola&rft.aufirst=Joseph&rft_id=http%3A%2F%2Fkth.diva-portal.org%2Fsmash%2Frecord.jsf%3Fpid%3Ddiva2%3A8730&rfr_id=info%3Asid%2Fen.wikipedia.org%3ACognitive+radio" class="Z3988"></span></span> </li> <li id="cite_note-V._Valenta_et_al.,_Survey_on_spectrum_utilization_in_Europe:_Measurements,_analyses_and_observations-2"><span class="mw-cite-backlink"><b><a href="#cite_ref-V._Valenta_et_al.,_Survey_on_spectrum_utilization_in_Europe:_Measurements,_analyses_and_observations_2-0">^</a></b></span> <span class="reference-text">V. Valenta et al., <a rel="nofollow" class="external text" href="http://hal.inria.fr/docs/00/49/20/21/PDF/paper9220_valenta.pdf">"Survey on spectrum utilization in Europe: Measurements, analyses and observations"</a>, Proceedings of the Fifth International Conference on Cognitive Radio Oriented Wireless Networks & Communications (CROWNCOM), 2010</span> </li> <li id="cite_note-3"><span class="mw-cite-backlink"><b><a href="#cite_ref-3">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite class="citation web cs1"><a rel="nofollow" class="external text" href="http://ieee802.org/22/P802_22_Revision_PAR_Approved.pdf">"P802.22"</a> <span class="cs1-format">(PDF)</span>. March 2014.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&rft.genre=unknown&rft.btitle=P802.22&rft.date=2014-03&rft_id=http%3A%2F%2Fieee802.org%2F22%2FP802_22_Revision_PAR_Approved.pdf&rfr_id=info%3Asid%2Fen.wikipedia.org%3ACognitive+radio" class="Z3988"></span></span> </li> <li id="cite_note-4"><span class="mw-cite-backlink"><b><a href="#cite_ref-4">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFStevensonChouinardZhongding_LeiWendong_Hu2009" class="citation journal cs1">Stevenson, C.; Chouinard, G.; Zhongding Lei; Wendong Hu; Shellhammer, S.; Caldwell, W. (2009). "IEEE 802.22: The First Cognitive Radio Wireless Regional Area Network Standard". <i>IEEE Communications Magazine</i>. <b>47</b>: 130–138. <a href="/wiki/Doi_(identifier)" class="mw-redirect" title="Doi (identifier)">doi</a>:<a rel="nofollow" class="external text" href="https://doi.org/10.1109%2FMCOM.2009.4752688">10.1109/MCOM.2009.4752688</a>. <a href="/wiki/S2CID_(identifier)" class="mw-redirect" title="S2CID (identifier)">S2CID</a> <a rel="nofollow" class="external text" href="https://api.semanticscholar.org/CorpusID:6597913">6597913</a>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.genre=article&rft.jtitle=IEEE+Communications+Magazine&rft.atitle=IEEE+802.22%3A+The+First+Cognitive+Radio+Wireless+Regional+Area+Network+Standard&rft.volume=47&rft.pages=130-138&rft.date=2009&rft_id=info%3Adoi%2F10.1109%2FMCOM.2009.4752688&rft_id=https%3A%2F%2Fapi.semanticscholar.org%2FCorpusID%3A6597913%23id-name%3DS2CID&rft.aulast=Stevenson&rft.aufirst=C.&rft.au=Chouinard%2C+G.&rft.au=Zhongding+Lei&rft.au=Wendong+Hu&rft.au=Shellhammer%2C+S.&rft.au=Caldwell%2C+W.&rfr_id=info%3Asid%2Fen.wikipedia.org%3ACognitive+radio" class="Z3988"></span></span> </li> <li id="cite_note-5"><span class="mw-cite-backlink"><b><a href="#cite_ref-5">^</a></b></span> <span class="reference-text"><a rel="nofollow" class="external text" href="https://ieeexplore.ieee.org/document/788210">J. Mitola III and G. Q. Maguire, Jr., "Cognitive radio: making software radios more personal," IEEE Personal Communications Magazine, vol. 6, nr. 4, pp. 13–18, Aug. 1999</a></span> </li> <li id="cite_note-6"><span class="mw-cite-backlink"><b><a href="#cite_ref-6">^</a></b></span> <span class="reference-text"><a rel="nofollow" class="external text" href="http://ieee802.org/22/">IEEE 802.22</a></span> </li> <li id="cite_note-Carl2009-7"><span class="mw-cite-backlink"><b><a href="#cite_ref-Carl2009_7-0">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFCarlG._ChouinardZhongding_LeiWendong_Hu2009" class="citation journal cs1">Carl, Stevenson; G. Chouinard; Zhongding Lei; Wendong Hu; S. Shellhammer; W. Caldwell (January 2009). <a href="/wiki/IEEE_Communications_Magazine" title="IEEE Communications Magazine">"IEEE 802.22: The First Cognitive Radio Wireless Regional Area Networks (WRANs) Standard = IEEE Communications Magazine"</a>. <i>IEEE Communications Magazine</i>. <b>47</b> (1): 130–138. <a href="/wiki/Doi_(identifier)" class="mw-redirect" title="Doi (identifier)">doi</a>:<a rel="nofollow" class="external text" href="https://doi.org/10.1109%2FMCOM.2009.4752688">10.1109/MCOM.2009.4752688</a>. <a href="/wiki/S2CID_(identifier)" class="mw-redirect" title="S2CID (identifier)">S2CID</a> <a rel="nofollow" class="external text" href="https://api.semanticscholar.org/CorpusID:6597913">6597913</a>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.genre=article&rft.jtitle=IEEE+Communications+Magazine&rft.atitle=IEEE+802.22%3A+The+First+Cognitive+Radio+Wireless+Regional+Area+Networks+%28WRANs%29+Standard+%3D+IEEE+Communications+Magazine&rft.volume=47&rft.issue=1&rft.pages=130-138&rft.date=2009-01&rft_id=info%3Adoi%2F10.1109%2FMCOM.2009.4752688&rft_id=https%3A%2F%2Fapi.semanticscholar.org%2FCorpusID%3A6597913%23id-name%3DS2CID&rft.aulast=Carl&rft.aufirst=Stevenson&rft.au=G.+Chouinard&rft.au=Zhongding+Lei&rft.au=Wendong+Hu&rft.au=S.+Shellhammer&rft.au=W.+Caldwell&rfr_id=info%3Asid%2Fen.wikipedia.org%3ACognitive+radio" class="Z3988"></span></span> </li> <li id="cite_note-8"><span class="mw-cite-backlink"><b><a href="#cite_ref-8">^</a></b></span> <span class="reference-text"><a rel="nofollow" class="external text" href="http://ieee802.org/15/pub/TG2.html">IEEE 802.15.2</a></span> </li> <li id="cite_note-ieeexplore.ieee.org-9"><span class="mw-cite-backlink"><b><a href="#cite_ref-ieeexplore.ieee.org_9-0">^</a></b></span> <span class="reference-text"><a rel="nofollow" class="external text" href="https://ieeexplore.ieee.org/search/srchabstract.jsp?arnumber=1391031&isnumber=30289&punumber=49&k2dockey=1391031@ieeejrns&query=(haykin+%3Cin%3E+metadata)+%3Cand%3E+(49+%3Cin%3E+punumber)&pos=0&access=no">S. Haykin, "Cognitive Radio: Brain-empowered Wireless Communications", IEEE Journal on Selected Areas of Communications, vol. 23, nr. 2, pp. 201–220, Feb. 2005</a></span> </li> <li id="cite_note-10"><span class="mw-cite-backlink"><b><a href="#cite_ref-10">^</a></b></span> <span class="reference-text">X. Kang et. al <i><a rel="nofollow" class="external text" href="https://ieeexplore.ieee.org/xpl/articleDetails.jsp?tp=&arnumber=4804658&queryText%3DSensing-based+spectrum+sharing+in+cognitive+radio+networks">Sensing-Based Spectrum Sharing in Cognitive Radio Networks</a>,</i> IEEE Transactions on Vehicular Technology, vol. 58, no. 8, pp. 4649–4654, Oct 2009.</span> </li> <li id="cite_note-11"><span class="mw-cite-backlink"><b><a href="#cite_ref-11">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFVillardiHaradaKojimaYano2016" class="citation journal cs1">Villardi, Gabriel Porto; Harada, Hiroshi; Kojima, Fumihide; Yano, Hiroyuki (2016). "Primary Contour Prediction based on Detailed Topographic Data and its Impact on TV White Space Availability". <i>IEEE Transactions on Antennas and Propagation</i>. <b>64</b> (8): 3619–3631. <a href="/wiki/Bibcode_(identifier)" class="mw-redirect" title="Bibcode (identifier)">Bibcode</a>:<a rel="nofollow" class="external text" href="https://ui.adsabs.harvard.edu/abs/2016ITAP...64.3619V">2016ITAP...64.3619V</a>. <a href="/wiki/Doi_(identifier)" class="mw-redirect" title="Doi (identifier)">doi</a>:<a rel="nofollow" class="external text" href="https://doi.org/10.1109%2FTAP.2016.2580164">10.1109/TAP.2016.2580164</a>. <a href="/wiki/S2CID_(identifier)" class="mw-redirect" title="S2CID (identifier)">S2CID</a> <a rel="nofollow" class="external text" href="https://api.semanticscholar.org/CorpusID:22471055">22471055</a>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.genre=article&rft.jtitle=IEEE+Transactions+on+Antennas+and+Propagation&rft.atitle=Primary+Contour+Prediction+based+on+Detailed+Topographic+Data+and+its+Impact+on+TV+White+Space+Availability&rft.volume=64&rft.issue=8&rft.pages=3619-3631&rft.date=2016&rft_id=https%3A%2F%2Fapi.semanticscholar.org%2FCorpusID%3A22471055%23id-name%3DS2CID&rft_id=info%3Adoi%2F10.1109%2FTAP.2016.2580164&rft_id=info%3Abibcode%2F2016ITAP...64.3619V&rft.aulast=Villardi&rft.aufirst=Gabriel+Porto&rft.au=Harada%2C+Hiroshi&rft.au=Kojima%2C+Fumihide&rft.au=Yano%2C+Hiroyuki&rfr_id=info%3Asid%2Fen.wikipedia.org%3ACognitive+radio" class="Z3988"></span></span> </li> <li id="cite_note-12"><span class="mw-cite-backlink"><b><a href="#cite_ref-12">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFVillardiHaradaKojimaYano2017" class="citation journal cs1">Villardi, Gabriel Porto; Harada, Hiroshi; Kojima, Fumihide; Yano, Hiroyuki (2017). "Multi-Level Protection to Broadcaster Contour and its Impact on TV White Space Availability". <i>IEEE Transactions on Vehicular Technology</i>. <b>66</b> (2): 1393–1407. <a href="/wiki/Doi_(identifier)" class="mw-redirect" title="Doi (identifier)">doi</a>:<a rel="nofollow" class="external text" href="https://doi.org/10.1109%2FTVT.2016.2566675">10.1109/TVT.2016.2566675</a>. <a href="/wiki/S2CID_(identifier)" class="mw-redirect" title="S2CID (identifier)">S2CID</a> <a rel="nofollow" class="external text" href="https://api.semanticscholar.org/CorpusID:206819681">206819681</a>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.genre=article&rft.jtitle=IEEE+Transactions+on+Vehicular+Technology&rft.atitle=Multi-Level+Protection+to+Broadcaster+Contour+and+its+Impact+on+TV+White+Space+Availability&rft.volume=66&rft.issue=2&rft.pages=1393-1407&rft.date=2017&rft_id=info%3Adoi%2F10.1109%2FTVT.2016.2566675&rft_id=https%3A%2F%2Fapi.semanticscholar.org%2FCorpusID%3A206819681%23id-name%3DS2CID&rft.aulast=Villardi&rft.aufirst=Gabriel+Porto&rft.au=Harada%2C+Hiroshi&rft.au=Kojima%2C+Fumihide&rft.au=Yano%2C+Hiroyuki&rfr_id=info%3Asid%2Fen.wikipedia.org%3ACognitive+radio" class="Z3988"></span></span> </li> <li id="cite_note-13"><span class="mw-cite-backlink"><b><a href="#cite_ref-13">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite class="citation web cs1"><a rel="nofollow" class="external text" href="https://www.fcc.gov/general/white-space-database-administrators-guide">"White Space Database Administrators Guide"</a>. The Federal Communications Commission (FCC). 12 October 2011.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&rft.genre=unknown&rft.btitle=White+Space+Database+Administrators+Guide&rft.pub=The+Federal+Communications+Commission+%28FCC%29&rft.date=2011-10-12&rft_id=https%3A%2F%2Fwww.fcc.gov%2Fgeneral%2Fwhite-space-database-administrators-guide&rfr_id=info%3Asid%2Fen.wikipedia.org%3ACognitive+radio" class="Z3988"></span></span> </li> <li id="cite_note-14"><span class="mw-cite-backlink"><b><a href="#cite_ref-14">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFNiels_HovenRahul_TandraAnant_Sahai2005" class="citation web cs1">Niels Hoven; Rahul Tandra; Anant Sahai (11 February 2005). <a rel="nofollow" class="external text" href="https://web.archive.org/web/20061218061944/http://www.eecs.berkeley.edu/wireless/posters/WFW05_cognitive.pdf">"Some Fundamental Limits on Cognitive Radio"</a> <span class="cs1-format">(PDF)</span>. Archived from <a rel="nofollow" class="external text" href="http://www.eecs.berkeley.edu/wireless/posters/WFW05_cognitive.pdf">the original</a> <span class="cs1-format">(PDF)</span> on 18 December 2006<span class="reference-accessdate">. Retrieved <span class="nowrap">15 June</span> 2005</span>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&rft.genre=unknown&rft.btitle=Some+Fundamental+Limits+on+Cognitive+Radio&rft.date=2005-02-11&rft.au=Niels+Hoven&rft.au=Rahul+Tandra&rft.au=Anant+Sahai&rft_id=http%3A%2F%2Fwww.eecs.berkeley.edu%2Fwireless%2Fposters%2FWFW05_cognitive.pdf&rfr_id=info%3Asid%2Fen.wikipedia.org%3ACognitive+radio" class="Z3988"></span></span> </li> <li id="cite_note-15"><span class="mw-cite-backlink"><b><a href="#cite_ref-15">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFJ._HillenbrandT._A._WeissF._K._Jondral2005" class="citation journal cs1">J. Hillenbrand; T. A. Weiss; F. K. Jondral (2005). "Calculation of detection and false alarm probabilities in spectrum pooling systems". <i>IEEE Communications Letters</i>. <b>9</b> (4): 349–351. <a href="/wiki/Doi_(identifier)" class="mw-redirect" title="Doi (identifier)">doi</a>:<a rel="nofollow" class="external text" href="https://doi.org/10.1109%2FLCOMM.2005.1413630">10.1109/LCOMM.2005.1413630</a>. <a href="/wiki/ISSN_(identifier)" class="mw-redirect" title="ISSN (identifier)">ISSN</a> <a rel="nofollow" class="external text" href="https://search.worldcat.org/issn/1089-7798">1089-7798</a>. <a href="/wiki/S2CID_(identifier)" class="mw-redirect" title="S2CID (identifier)">S2CID</a> <a rel="nofollow" class="external text" href="https://api.semanticscholar.org/CorpusID:23646184">23646184</a>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.genre=article&rft.jtitle=IEEE+Communications+Letters&rft.atitle=Calculation+of+detection+and+false+alarm+probabilities+in+spectrum+pooling+systems&rft.volume=9&rft.issue=4&rft.pages=349-351&rft.date=2005&rft_id=https%3A%2F%2Fapi.semanticscholar.org%2FCorpusID%3A23646184%23id-name%3DS2CID&rft.issn=1089-7798&rft_id=info%3Adoi%2F10.1109%2FLCOMM.2005.1413630&rft.au=J.+Hillenbrand&rft.au=T.+A.+Weiss&rft.au=F.+K.+Jondral&rfr_id=info%3Asid%2Fen.wikipedia.org%3ACognitive+radio" class="Z3988"></span></span> </li> <li id="cite_note-16"><span class="mw-cite-backlink"><b><a href="#cite_ref-16">^</a></b></span> <span class="reference-text"><a href="/wiki/Ian_F._Akyildiz" title="Ian F. Akyildiz">Ian F. Akyildiz</a>, W.-Y. Lee, M. C. Vuran, and S. Mohanty, "NeXt Generation/Dynamic Spectrum Access/Cognitive Radio Wireless Networks: A Survey," Computer Networks (Elsevier) Journal, September 2006. <a rel="nofollow" class="external autonumber" href="http://www.ece.gatech.edu/research/labs/bwn/surveys/radio.pdf">[1]</a></span> </li> <li id="cite_note-17"><span class="mw-cite-backlink"><b><a href="#cite_ref-17">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite class="citation web cs1"><a rel="nofollow" class="external text" href="https://web.archive.org/web/20081118234117/http://grouper.ieee.org/groups/scc41/files/Communications_Magazine_article_on_SCC41.pdf">"Cognitive Functionality in Next Generation Wireless Networks"</a> <span class="cs1-format">(PDF)</span>. Archived from <a rel="nofollow" class="external text" href="http://grouper.ieee.org/groups/scc41/files/Communications_Magazine_article_on_SCC41.pdf">the original</a> <span class="cs1-format">(PDF)</span> on 18 November 2008<span class="reference-accessdate">. Retrieved <span class="nowrap">6 June</span> 2009</span>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&rft.genre=unknown&rft.btitle=Cognitive+Functionality+in+Next+Generation+Wireless+Networks&rft_id=http%3A%2F%2Fgrouper.ieee.org%2Fgroups%2Fscc41%2Ffiles%2FCommunications_Magazine_article_on_SCC41.pdf&rfr_id=info%3Asid%2Fen.wikipedia.org%3ACognitive+radio" class="Z3988"></span></span> </li> <li id="cite_note-18"><span class="mw-cite-backlink"><b><a href="#cite_ref-18">^</a></b></span> <span class="reference-text">X. Kang et. al <a rel="nofollow" class="external text" href="https://ieeexplore.ieee.org/document/4786456/">"Optimal power allocation for fading channels in cognitive radio networks: Ergodic capacity and outage capacity"</a>, <i> IEEE Trans. on Wireless Commun.</i>, vol. 8, no. 2, pp. 940–950, Feb 2009.</span> </li> <li id="cite_note-dx.doi.org-19"><span class="mw-cite-backlink"><b><a href="#cite_ref-dx.doi.org_19-0">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFUrkowitz1967" class="citation journal cs1">Urkowitz, H. (1967). "Energy detection of unknown deterministic signals". <i>Proceedings of the IEEE</i>. <b>55</b> (4): 523–531. <a href="/wiki/Doi_(identifier)" class="mw-redirect" title="Doi (identifier)">doi</a>:<a rel="nofollow" class="external text" href="https://doi.org/10.1109%2FPROC.1967.5573">10.1109/PROC.1967.5573</a>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.genre=article&rft.jtitle=Proceedings+of+the+IEEE&rft.atitle=Energy+detection+of+unknown+deterministic+signals&rft.volume=55&rft.issue=4&rft.pages=523-531&rft.date=1967&rft_id=info%3Adoi%2F10.1109%2FPROC.1967.5573&rft.aulast=Urkowitz&rft.aufirst=H.&rfr_id=info%3Asid%2Fen.wikipedia.org%3ACognitive+radio" class="Z3988"></span></span> </li> <li id="cite_note-20"><span class="mw-cite-backlink"><b><a href="#cite_ref-20">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFTandraSahai2008" class="citation journal cs1">Tandra, Rahul; Sahai, Anant (2008). "SNR Walls for Signal Detection". <i>IEEE Journal of Selected Topics in Signal Processing</i>. <b>2</b> (1): 4–17. <a href="/wiki/Bibcode_(identifier)" class="mw-redirect" title="Bibcode (identifier)">Bibcode</a>:<a rel="nofollow" class="external text" href="https://ui.adsabs.harvard.edu/abs/2008ISTSP...2....4T">2008ISTSP...2....4T</a>. <a href="/wiki/CiteSeerX_(identifier)" class="mw-redirect" title="CiteSeerX (identifier)">CiteSeerX</a> <span class="id-lock-free" title="Freely accessible"><a rel="nofollow" class="external text" href="https://citeseerx.ist.psu.edu/viewdoc/summary?doi=10.1.1.420.9680">10.1.1.420.9680</a></span>. <a href="/wiki/Doi_(identifier)" class="mw-redirect" title="Doi (identifier)">doi</a>:<a rel="nofollow" class="external text" href="https://doi.org/10.1109%2FJSTSP.2007.914879">10.1109/JSTSP.2007.914879</a>. <a href="/wiki/S2CID_(identifier)" class="mw-redirect" title="S2CID (identifier)">S2CID</a> <a rel="nofollow" class="external text" href="https://api.semanticscholar.org/CorpusID:14450540">14450540</a>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.genre=article&rft.jtitle=IEEE+Journal+of+Selected+Topics+in+Signal+Processing&rft.atitle=SNR+Walls+for+Signal+Detection&rft.volume=2&rft.issue=1&rft.pages=4-17&rft.date=2008&rft_id=https%3A%2F%2Fciteseerx.ist.psu.edu%2Fviewdoc%2Fsummary%3Fdoi%3D10.1.1.420.9680%23id-name%3DCiteSeerX&rft_id=https%3A%2F%2Fapi.semanticscholar.org%2FCorpusID%3A14450540%23id-name%3DS2CID&rft_id=info%3Adoi%2F10.1109%2FJSTSP.2007.914879&rft_id=info%3Abibcode%2F2008ISTSP...2....4T&rft.aulast=Tandra&rft.aufirst=Rahul&rft.au=Sahai%2C+Anant&rfr_id=info%3Asid%2Fen.wikipedia.org%3ACognitive+radio" class="Z3988"></span></span> </li> <li id="cite_note-margiochi-21"><span class="mw-cite-backlink"><b><a href="#cite_ref-margiochi_21-0">^</a></b></span> <span class="reference-text">A. Mariani, A. Giorgetti, and M. Chiani, <a rel="nofollow" class="external text" href="https://ieeexplore.ieee.org/xpls/abs_all.jsp?arnumber=6068200">"Effects of Noise Power Estimation on Energy Detection for Cognitive Radio Applications"</a>, IEEE Trans. Commun., vol. 50, no. 12, Dec., 2011.</span> </li> <li id="cite_note-22"><span class="mw-cite-backlink"><b><a href="#cite_ref-22">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFGardner1991" class="citation journal cs1">Gardner, W.A. (1991). "Exploitation of spectral redundancy in cyclostationary signals". <i>IEEE Signal Processing Magazine</i>. <b>8</b> (2): 14–36. <a href="/wiki/Bibcode_(identifier)" class="mw-redirect" title="Bibcode (identifier)">Bibcode</a>:<a rel="nofollow" class="external text" href="https://ui.adsabs.harvard.edu/abs/1991ISPM....8...14G">1991ISPM....8...14G</a>. <a href="/wiki/Doi_(identifier)" class="mw-redirect" title="Doi (identifier)">doi</a>:<a rel="nofollow" class="external text" href="https://doi.org/10.1109%2F79.81007">10.1109/79.81007</a>. <a href="/wiki/S2CID_(identifier)" class="mw-redirect" title="S2CID (identifier)">S2CID</a> <a rel="nofollow" class="external text" href="https://api.semanticscholar.org/CorpusID:21643558">21643558</a>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.genre=article&rft.jtitle=IEEE+Signal+Processing+Magazine&rft.atitle=Exploitation+of+spectral+redundancy+in+cyclostationary+signals&rft.volume=8&rft.issue=2&rft.pages=14-36&rft.date=1991&rft_id=https%3A%2F%2Fapi.semanticscholar.org%2FCorpusID%3A21643558%23id-name%3DS2CID&rft_id=info%3Adoi%2F10.1109%2F79.81007&rft_id=info%3Abibcode%2F1991ISPM....8...14G&rft.aulast=Gardner&rft.aufirst=W.A.&rfr_id=info%3Asid%2Fen.wikipedia.org%3ACognitive+radio" class="Z3988"></span></span> </li> <li id="cite_note-cse.wustl.edu-23"><span class="mw-cite-backlink">^ <a href="#cite_ref-cse.wustl.edu_23-0"><sup><i><b>a</b></i></sup></a> <a href="#cite_ref-cse.wustl.edu_23-1"><sup><i><b>b</b></i></sup></a></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite class="citation web cs1"><a rel="nofollow" class="external text" href="https://www.cse.wustl.edu/~jain/cse574-14/ftp/cr/index.html">"Recent Advances in Cognitive Radios"</a>. <i>cse.wustl.edu</i><span class="reference-accessdate">. Retrieved <span class="nowrap">22 September</span> 2019</span>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.genre=unknown&rft.jtitle=cse.wustl.edu&rft.atitle=Recent+Advances+in+Cognitive+Radios&rft_id=https%3A%2F%2Fwww.cse.wustl.edu%2F~jain%2Fcse574-14%2Fftp%2Fcr%2Findex.html&rfr_id=info%3Asid%2Fen.wikipedia.org%3ACognitive+radio" class="Z3988"></span></span> </li> <li id="cite_note-24"><span class="mw-cite-backlink"><b><a href="#cite_ref-24">^</a></b></span> <span class="reference-text">H. Sun, A. Nallanathan, C.-X. Wang, and Y.-F. Chen, <a rel="nofollow" class="external text" href="https://ieeexplore.ieee.org/xpl/articleDetails.jsp?reload=true&arnumber=6507397">"Wideband spectrum sensing for cognitive radio networks: a survey"</a>, IEEE Wireless Communications, vol. 20, no. 2, pp. 74–81, April 2013.</span> </li> <li id="cite_note-25"><span class="mw-cite-backlink"><b><a href="#cite_ref-25">^</a></b></span> <span class="reference-text">Z. Li, F.R. Yu, and M. Huang, <a rel="nofollow" class="external text" href="https://ieeexplore.ieee.org/document/5229125/;jsessionid=7B7903E7E64303079346DA7DD9EC77DA?arnumber=5229125">"A Distributed Consensus-Based Cooperative Spectrum Sensing in Cognitive Radios"</a>, IEEE Trans. Vehicular Technology, vol. 59, no. 1, pp. 383–393, Jan. 2010.</span> </li> <li id="cite_note-26"><span class="mw-cite-backlink"><b><a href="#cite_ref-26">^</a></b></span> <span class="reference-text">K. Kotobi, P. B. Mainwaring, and S. G. Bilen, <a rel="nofollow" class="external text" href="https://ieeexplore.ieee.org/document/7763240/#full-text-section">"Puzzle-based auction mechanism for spectrum sharing in cognitive radio networks"</a>, Wireless and Mobile Computing, Networking and Communications (WiMob), 2016 IEEE 12th International Conference on, October 2016.</span> </li> <li id="cite_note-27"><span class="mw-cite-backlink"><b><a href="#cite_ref-27">^</a></b></span> <span class="reference-text">The word "cyclistationary" is an error from the source passage, and the correct one is cyclostationary.</span> </li> <li id="cite_note-28"><span class="mw-cite-backlink"><b><a href="#cite_ref-28">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFMartinez_AlonsoPletsDeruyckMartens2020" class="citation journal cs1">Martinez Alonso, Rodney; Plets, David; Deruyck, Margot; Martens, Luc; Guillen Nieto, Glauco; Joseph, Wout (9 May 2020). <a rel="nofollow" class="external text" href="https://doi.org/10.1155%2F2020%2F2850528">"Dynamic Interference Optimization in Cognitive Radio Networks for Rural and Suburban Areas"</a>. <i>Wireless Communications and Mobile Computing</i>. <b>2020</b>: 1–16. <a href="/wiki/Doi_(identifier)" class="mw-redirect" title="Doi (identifier)">doi</a>:<span class="id-lock-free" title="Freely accessible"><a rel="nofollow" class="external text" href="https://doi.org/10.1155%2F2020%2F2850528">10.1155/2020/2850528</a></span>. <a href="/wiki/Hdl_(identifier)" class="mw-redirect" title="Hdl (identifier)">hdl</a>:<span class="id-lock-free" title="Freely accessible"><a rel="nofollow" class="external text" href="https://hdl.handle.net/1854%2FLU-8672730">1854/LU-8672730</a></span>. <a href="/wiki/ISSN_(identifier)" class="mw-redirect" title="ISSN (identifier)">ISSN</a> <a rel="nofollow" class="external text" href="https://search.worldcat.org/issn/1530-8669">1530-8669</a>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.genre=article&rft.jtitle=Wireless+Communications+and+Mobile+Computing&rft.atitle=Dynamic+Interference+Optimization+in+Cognitive+Radio+Networks+for+Rural+and+Suburban+Areas&rft.volume=2020&rft.pages=1-16&rft.date=2020-05-09&rft_id=info%3Ahdl%2F1854%2FLU-8672730&rft.issn=1530-8669&rft_id=info%3Adoi%2F10.1155%2F2020%2F2850528&rft.aulast=Martinez+Alonso&rft.aufirst=Rodney&rft.au=Plets%2C+David&rft.au=Deruyck%2C+Margot&rft.au=Martens%2C+Luc&rft.au=Guillen+Nieto%2C+Glauco&rft.au=Joseph%2C+Wout&rft_id=https%3A%2F%2Fdoi.org%2F10.1155%252F2020%252F2850528&rfr_id=info%3Asid%2Fen.wikipedia.org%3ACognitive+radio" class="Z3988"></span></span> </li> <li id="cite_note-29"><span class="mw-cite-backlink"><b><a href="#cite_ref-29">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFMartinez_AlonsoPletsMartensJoseph2023" class="citation journal cs1">Martinez Alonso, Rodney; Plets, David; Martens, Luc; Joseph, Wout; Fontes Pupo, Ernesto; Guillen Nieto, Glauco (1 September 2023). <a rel="nofollow" class="external text" href="https://www.sciencedirect.com/science/article/pii/S138912862300316X">"White spaces pattern finding and inference based on machine learning for multi-frequency spectrum footprints"</a>. <i>Computer Networks</i>. <b>233</b>: 109871. <a href="/wiki/Doi_(identifier)" class="mw-redirect" title="Doi (identifier)">doi</a>:<a rel="nofollow" class="external text" href="https://doi.org/10.1016%2Fj.comnet.2023.109871">10.1016/j.comnet.2023.109871</a>. <a href="/wiki/Hdl_(identifier)" class="mw-redirect" title="Hdl (identifier)">hdl</a>:<span class="id-lock-free" title="Freely accessible"><a rel="nofollow" class="external text" href="https://hdl.handle.net/1854%2FLU-01HGAPQWFZNJYT40GNBAC025PS">1854/LU-01HGAPQWFZNJYT40GNBAC025PS</a></span>. <a href="/wiki/ISSN_(identifier)" class="mw-redirect" title="ISSN (identifier)">ISSN</a> <a rel="nofollow" class="external text" href="https://search.worldcat.org/issn/1389-1286">1389-1286</a>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.genre=article&rft.jtitle=Computer+Networks&rft.atitle=White+spaces+pattern+finding+and+inference+based+on+machine+learning+for+multi-frequency+spectrum+footprints&rft.volume=233&rft.pages=109871&rft.date=2023-09-01&rft_id=info%3Ahdl%2F1854%2FLU-01HGAPQWFZNJYT40GNBAC025PS&rft.issn=1389-1286&rft_id=info%3Adoi%2F10.1016%2Fj.comnet.2023.109871&rft.aulast=Martinez+Alonso&rft.aufirst=Rodney&rft.au=Plets%2C+David&rft.au=Martens%2C+Luc&rft.au=Joseph%2C+Wout&rft.au=Fontes+Pupo%2C+Ernesto&rft.au=Guillen+Nieto%2C+Glauco&rft_id=https%3A%2F%2Fwww.sciencedirect.com%2Fscience%2Farticle%2Fpii%2FS138912862300316X&rfr_id=info%3Asid%2Fen.wikipedia.org%3ACognitive+radio" class="Z3988"></span></span> </li> <li id="cite_note-30"><span class="mw-cite-backlink"><b><a href="#cite_ref-30">^</a></b></span> <span class="reference-text">B. Kouassi, I. Ghauri, L. Deneire, <a rel="nofollow" class="external text" href="http://hal.archives-ouvertes.fr/hal-00845407/">"Reciprocity-based cognitive transmissions using a MU massive MIMO approach"</a>. IEEE International Conference on Communications (ICC), 2013</span> </li> <li id="cite_note-31"><span class="mw-cite-backlink"><b><a href="#cite_ref-31">^</a></b></span> <span class="reference-text"><a rel="nofollow" class="external text" href="http://www.mdpi.com/2079-9292/4/2/221/pdf">K. Kotobi, P. B. Mainwaring, C. S. Tucker, and S. G. Bilén., "Data-Throughput Enhancement Using Data Mining-Informed Cognitive Radio." Electronics 4, no. 2 (2015): 221-238.</a></span> </li> <li id="cite_note-32"><span class="mw-cite-backlink"><b><a href="#cite_ref-32">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFVillardiAbreuHarada2012" class="citation journal cs1">Villardi, G. P.; Abreu, G. Thadeu Freitas de; Harada, H. (1 June 2012). "TV White Space Technology: Interference in Portable Cognitive Emergency Network". <i>IEEE Vehicular Technology Magazine</i>. <b>7</b> (2): 47–53. <a href="/wiki/Doi_(identifier)" class="mw-redirect" title="Doi (identifier)">doi</a>:<a rel="nofollow" class="external text" href="https://doi.org/10.1109%2FMVT.2012.2190221">10.1109/MVT.2012.2190221</a>. <a href="/wiki/ISSN_(identifier)" class="mw-redirect" title="ISSN (identifier)">ISSN</a> <a rel="nofollow" class="external text" href="https://search.worldcat.org/issn/1556-6072">1556-6072</a>. <a href="/wiki/S2CID_(identifier)" class="mw-redirect" title="S2CID (identifier)">S2CID</a> <a rel="nofollow" class="external text" href="https://api.semanticscholar.org/CorpusID:33102841">33102841</a>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.genre=article&rft.jtitle=IEEE+Vehicular+Technology+Magazine&rft.atitle=TV+White+Space+Technology%3A+Interference+in+Portable+Cognitive+Emergency+Network&rft.volume=7&rft.issue=2&rft.pages=47-53&rft.date=2012-06-01&rft_id=https%3A%2F%2Fapi.semanticscholar.org%2FCorpusID%3A33102841%23id-name%3DS2CID&rft.issn=1556-6072&rft_id=info%3Adoi%2F10.1109%2FMVT.2012.2190221&rft.aulast=Villardi&rft.aufirst=G.+P.&rft.au=Abreu%2C+G.+Thadeu+Freitas+de&rft.au=Harada%2C+H.&rfr_id=info%3Asid%2Fen.wikipedia.org%3ACognitive+radio" class="Z3988"></span></span> </li> <li id="cite_note-33"><span class="mw-cite-backlink"><b><a href="#cite_ref-33">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFFerrusSallentBaldiniGoratti2012" class="citation journal cs1">Ferrus, R.; Sallent, O.; Baldini, G.; Goratti, L. (1 June 2012). "Public Safety Communications: Enhancement Through Cognitive Radio and Spectrum Sharing Principles". <i>IEEE Vehicular Technology Magazine</i>. <b>7</b> (2): 54–61. <a href="/wiki/Doi_(identifier)" class="mw-redirect" title="Doi (identifier)">doi</a>:<a rel="nofollow" class="external text" href="https://doi.org/10.1109%2FMVT.2012.2190180">10.1109/MVT.2012.2190180</a>. <a href="/wiki/ISSN_(identifier)" class="mw-redirect" title="ISSN (identifier)">ISSN</a> <a rel="nofollow" class="external text" href="https://search.worldcat.org/issn/1556-6072">1556-6072</a>. <a href="/wiki/S2CID_(identifier)" class="mw-redirect" title="S2CID (identifier)">S2CID</a> <a rel="nofollow" class="external text" href="https://api.semanticscholar.org/CorpusID:24372449">24372449</a>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.genre=article&rft.jtitle=IEEE+Vehicular+Technology+Magazine&rft.atitle=Public+Safety+Communications%3A+Enhancement+Through+Cognitive+Radio+and+Spectrum+Sharing+Principles&rft.volume=7&rft.issue=2&rft.pages=54-61&rft.date=2012-06-01&rft_id=https%3A%2F%2Fapi.semanticscholar.org%2FCorpusID%3A24372449%23id-name%3DS2CID&rft.issn=1556-6072&rft_id=info%3Adoi%2F10.1109%2FMVT.2012.2190180&rft.aulast=Ferrus&rft.aufirst=R.&rft.au=Sallent%2C+O.&rft.au=Baldini%2C+G.&rft.au=Goratti%2C+L.&rfr_id=info%3Asid%2Fen.wikipedia.org%3ACognitive+radio" class="Z3988"></span></span> </li> <li id="cite_note-34"><span class="mw-cite-backlink"><b><a href="#cite_ref-34">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFKhattabPerkinsBayoumi2013" class="citation book cs1">Khattab, Ahmed; Perkins, Dmitri; Bayoumi, Magdy (1 January 2013). "Opportunistic Spectrum Access Challenges in Distributed Cognitive Radio Networks". <i>Cognitive Radio Networks</i>. Analog Circuits and Signal Processing. Springer New York. pp. 33–39. <a href="/wiki/Doi_(identifier)" class="mw-redirect" title="Doi (identifier)">doi</a>:<a rel="nofollow" class="external text" href="https://doi.org/10.1007%2F978-1-4614-4033-8_4">10.1007/978-1-4614-4033-8_4</a>. <a href="/wiki/ISBN_(identifier)" class="mw-redirect" title="ISBN (identifier)">ISBN</a> <a href="/wiki/Special:BookSources/978-1-4614-4032-1" title="Special:BookSources/978-1-4614-4032-1"><bdi>978-1-4614-4032-1</bdi></a>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&rft.genre=bookitem&rft.atitle=Opportunistic+Spectrum+Access+Challenges+in+Distributed+Cognitive+Radio+Networks&rft.btitle=Cognitive+Radio+Networks&rft.series=Analog+Circuits+and+Signal+Processing&rft.pages=33-39&rft.pub=Springer+New+York&rft.date=2013-01-01&rft_id=info%3Adoi%2F10.1007%2F978-1-4614-4033-8_4&rft.isbn=978-1-4614-4032-1&rft.aulast=Khattab&rft.aufirst=Ahmed&rft.au=Perkins%2C+Dmitri&rft.au=Bayoumi%2C+Magdy&rfr_id=info%3Asid%2Fen.wikipedia.org%3ACognitive+radio" class="Z3988"></span></span> </li> <li id="cite_note-35"><span class="mw-cite-backlink"><b><a href="#cite_ref-35">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFTallonFordeDoyle2012" class="citation journal cs1">Tallon, J.; Forde, T. K.; Doyle, L. (1 June 2012). <a rel="nofollow" class="external text" href="https://zenodo.org/record/3433984">"Dynamic Spectrum Access Networks: Independent Coalition Formation"</a>. <i>IEEE Vehicular Technology Magazine</i>. <b>7</b> (2): 69–76. <a href="/wiki/Doi_(identifier)" class="mw-redirect" title="Doi (identifier)">doi</a>:<a rel="nofollow" class="external text" href="https://doi.org/10.1109%2FMVT.2012.2190218">10.1109/MVT.2012.2190218</a>. <a href="/wiki/ISSN_(identifier)" class="mw-redirect" title="ISSN (identifier)">ISSN</a> <a rel="nofollow" class="external text" href="https://search.worldcat.org/issn/1556-6072">1556-6072</a>. <a href="/wiki/S2CID_(identifier)" class="mw-redirect" title="S2CID (identifier)">S2CID</a> <a rel="nofollow" class="external text" href="https://api.semanticscholar.org/CorpusID:39842167">39842167</a>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.genre=article&rft.jtitle=IEEE+Vehicular+Technology+Magazine&rft.atitle=Dynamic+Spectrum+Access+Networks%3A+Independent+Coalition+Formation&rft.volume=7&rft.issue=2&rft.pages=69-76&rft.date=2012-06-01&rft_id=https%3A%2F%2Fapi.semanticscholar.org%2FCorpusID%3A39842167%23id-name%3DS2CID&rft.issn=1556-6072&rft_id=info%3Adoi%2F10.1109%2FMVT.2012.2190218&rft.aulast=Tallon&rft.aufirst=J.&rft.au=Forde%2C+T.+K.&rft.au=Doyle%2C+L.&rft_id=https%3A%2F%2Fzenodo.org%2Frecord%2F3433984&rfr_id=info%3Asid%2Fen.wikipedia.org%3ACognitive+radio" class="Z3988"></span></span> </li> <li id="cite_note-36"><span class="mw-cite-backlink"><b><a href="#cite_ref-36">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFJoshiNamKim2013" class="citation journal cs1">Joshi, Gyanendra Prasad; Nam, Seung Yeob; Kim, Sung Won (22 August 2013). <a rel="nofollow" class="external text" href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3821336">"Cognitive Radio Wireless Sensor Networks: Applications, Challenges and Research Trends"</a>. <i>Sensors (Basel, Switzerland)</i>. <b>13</b> (9): 11196–11228. <a href="/wiki/Bibcode_(identifier)" class="mw-redirect" title="Bibcode (identifier)">Bibcode</a>:<a rel="nofollow" class="external text" href="https://ui.adsabs.harvard.edu/abs/2013Senso..1311196J">2013Senso..1311196J</a>. <a href="/wiki/Doi_(identifier)" class="mw-redirect" title="Doi (identifier)">doi</a>:<span class="id-lock-free" title="Freely accessible"><a rel="nofollow" class="external text" href="https://doi.org/10.3390%2Fs130911196">10.3390/s130911196</a></span>. <a href="/wiki/ISSN_(identifier)" class="mw-redirect" title="ISSN (identifier)">ISSN</a> <a rel="nofollow" class="external text" href="https://search.worldcat.org/issn/1424-8220">1424-8220</a>. <a href="/wiki/PMC_(identifier)" class="mw-redirect" title="PMC (identifier)">PMC</a> <span class="id-lock-free" title="Freely accessible"><a rel="nofollow" class="external text" href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3821336">3821336</a></span>. <a href="/wiki/PMID_(identifier)" class="mw-redirect" title="PMID (identifier)">PMID</a> <a rel="nofollow" class="external text" href="https://pubmed.ncbi.nlm.nih.gov/23974152">23974152</a>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.genre=article&rft.jtitle=Sensors+%28Basel%2C+Switzerland%29&rft.atitle=Cognitive+Radio+Wireless+Sensor+Networks%3A+Applications%2C+Challenges+and+Research+Trends&rft.volume=13&rft.issue=9&rft.pages=11196-11228&rft.date=2013-08-22&rft_id=https%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fpmc%2Farticles%2FPMC3821336%23id-name%3DPMC&rft_id=info%3Abibcode%2F2013Senso..1311196J&rft_id=info%3Apmid%2F23974152&rft_id=info%3Adoi%2F10.3390%2Fs130911196&rft.issn=1424-8220&rft.aulast=Joshi&rft.aufirst=Gyanendra+Prasad&rft.au=Nam%2C+Seung+Yeob&rft.au=Kim%2C+Sung+Won&rft_id=https%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fpmc%2Farticles%2FPMC3821336&rfr_id=info%3Asid%2Fen.wikipedia.org%3ACognitive+radio" class="Z3988"></span></span> </li> <li id="cite_note-37"><span class="mw-cite-backlink"><b><a href="#cite_ref-37">^</a></b></span> <span class="reference-text">F. Foukalas and T. Khattab, "<a rel="nofollow" class="external text" href="https://ieeexplore.ieee.org/abstract/document/6971233">To Relay or Not to Relay in Cognitive Radio Sensor Networks</a>." IEEE Transactions on Vehicular Technology (vol. 64, no. 11, Nov. 2015 ) 5221-5231.</span> </li> <li id="cite_note-38"><span class="mw-cite-backlink"><b><a href="#cite_ref-38">^</a></b></span> <span class="reference-text"><a rel="nofollow" class="external text" href="http://cogns.net/">CogNS: A simulation framework for cognitive radio networks</a></span> </li> <li id="cite_note-simulationCR1-39"><span class="mw-cite-backlink">^ <a href="#cite_ref-simulationCR1_39-0"><sup><i><b>a</b></i></sup></a> <a href="#cite_ref-simulationCR1_39-1"><sup><i><b>b</b></i></sup></a></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFVillardiSumSunAlemseged2012" class="citation journal cs1">Villardi, Gabriel; Sum, Chin-Sean; Sun, Chen; Alemseged, Yohannes; Lan, Zhou; Harada, Hiroshi (2012). "Efficiency of Dynamic Frequency Selection Based Coexistence Mechanisms for TV White Space Enabled Cognitive Wireless Access Points". <i>IEEE Wireless Communications</i>. <b>19</b> (6): 69–75. <a href="/wiki/Doi_(identifier)" class="mw-redirect" title="Doi (identifier)">doi</a>:<a rel="nofollow" class="external text" href="https://doi.org/10.1109%2FMWC.2012.6393520">10.1109/MWC.2012.6393520</a>. <a href="/wiki/S2CID_(identifier)" class="mw-redirect" title="S2CID (identifier)">S2CID</a> <a rel="nofollow" class="external text" href="https://api.semanticscholar.org/CorpusID:3134504">3134504</a>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.genre=article&rft.jtitle=IEEE+Wireless+Communications&rft.atitle=Efficiency+of+Dynamic+Frequency+Selection+Based+Coexistence+Mechanisms+for+TV+White+Space+Enabled+Cognitive+Wireless+Access+Points&rft.volume=19&rft.issue=6&rft.pages=69-75&rft.date=2012&rft_id=info%3Adoi%2F10.1109%2FMWC.2012.6393520&rft_id=https%3A%2F%2Fapi.semanticscholar.org%2FCorpusID%3A3134504%23id-name%3DS2CID&rft.aulast=Villardi&rft.aufirst=Gabriel&rft.au=Sum%2C+Chin-Sean&rft.au=Sun%2C+Chen&rft.au=Alemseged%2C+Yohannes&rft.au=Lan%2C+Zhou&rft.au=Harada%2C+Hiroshi&rfr_id=info%3Asid%2Fen.wikipedia.org%3ACognitive+radio" class="Z3988"></span></span> </li> <li id="cite_note-simulationCR2-40"><span class="mw-cite-backlink">^ <a href="#cite_ref-simulationCR2_40-0"><sup><i><b>a</b></i></sup></a> <a href="#cite_ref-simulationCR2_40-1"><sup><i><b>b</b></i></sup></a></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFVillardiAlemsegedSunSum2011" class="citation journal cs1">Villardi, Gabriel; Alemseged, Yohannes; Sun, Chen; Sum, Chin-Sean; Nguyen, Tran; Baykas, Tuncer; Harada, Hiroshi (2011). "Enabling Coexistence of Multiple Cognitive Networks in TV White Space". <i>IEEE Wireless Communications</i>. <b>18</b> (4): 32–40. <a href="/wiki/Doi_(identifier)" class="mw-redirect" title="Doi (identifier)">doi</a>:<a rel="nofollow" class="external text" href="https://doi.org/10.1109%2FMWC.2011.5999762">10.1109/MWC.2011.5999762</a>. <a href="/wiki/S2CID_(identifier)" class="mw-redirect" title="S2CID (identifier)">S2CID</a> <a rel="nofollow" class="external text" href="https://api.semanticscholar.org/CorpusID:28929874">28929874</a>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.genre=article&rft.jtitle=IEEE+Wireless+Communications&rft.atitle=Enabling+Coexistence+of+Multiple+Cognitive+Networks+in+TV+White+Space&rft.volume=18&rft.issue=4&rft.pages=32-40&rft.date=2011&rft_id=info%3Adoi%2F10.1109%2FMWC.2011.5999762&rft_id=https%3A%2F%2Fapi.semanticscholar.org%2FCorpusID%3A28929874%23id-name%3DS2CID&rft.aulast=Villardi&rft.aufirst=Gabriel&rft.au=Alemseged%2C+Yohannes&rft.au=Sun%2C+Chen&rft.au=Sum%2C+Chin-Sean&rft.au=Nguyen%2C+Tran&rft.au=Baykas%2C+Tuncer&rft.au=Harada%2C+Hiroshi&rfr_id=info%3Asid%2Fen.wikipedia.org%3ACognitive+radio" class="Z3988"></span></span> </li> <li id="cite_note-A._Shattal,_A._Wisniewska_2018-41"><span class="mw-cite-backlink">^ <a href="#cite_ref-A._Shattal,_A._Wisniewska_2018_41-0"><sup><i><b>a</b></i></sup></a> <a href="#cite_ref-A._Shattal,_A._Wisniewska_2018_41-1"><sup><i><b>b</b></i></sup></a></span> <span class="reference-text">M. A. Shattal, A. Wisniewska, B. Khan, A. Al-Fuqaha and K. Dombrowski, "From Channel Selection to Strategy Selection: Enhancing VANETs Using Socially-Inspired Foraging and Deference Strategies," in IEEE Transactions on Vehicular Technology, vol. 67, no. 9, pp. 8919–8933, Sept. 2018. doi: 10.1109/TVT.2018.2853580 URL: <a rel="nofollow" class="external free" href="https://ieeexplore.ieee.org/stamp/stamp.jsp?tp=&arnumber=8403998&isnumber=8466982">https://ieeexplore.ieee.org/stamp/stamp.jsp?tp=&arnumber=8403998&isnumber=8466982</a></span> </li> <li id="cite_note-42"><span class="mw-cite-backlink"><b><a href="#cite_ref-42">^</a></b></span> <span class="reference-text">Carlos Cordeiro, Kiran Challapali, and Dagnachew Birru. Sai Shankar N. IEEE 802.22: An Introduction to the First Wireless Standard based on Cognitive Radios JOURNAL OF COMMUNICATIONS, VOL. 1, NO. 1, APRIL 2006</span> </li> <li id="cite_note-43"><span class="mw-cite-backlink"><b><a href="#cite_ref-43">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite class="citation web cs1"><a rel="nofollow" class="external text" href="https://www.ietf.org/proceedings/81/slides/paws-3.pdf">"The IEEE 802.22 WRAN Standard and its interface to the White Space Database"</a> <span class="cs1-format">(PDF)</span>. IETF PAWS.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&rft.genre=unknown&rft.btitle=The+IEEE+802.22+WRAN+Standard+and+its+interface+to+the+White+Space+Database&rft.pub=IETF+PAWS&rft_id=https%3A%2F%2Fwww.ietf.org%2Fproceedings%2F81%2Fslides%2Fpaws-3.pdf&rfr_id=info%3Asid%2Fen.wikipedia.org%3ACognitive+radio" class="Z3988"></span></span> </li> <li id="cite_note-44"><span class="mw-cite-backlink"><b><a href="#cite_ref-44">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFMartinez_AlonsoPletsMartensJoseph2023" class="citation journal cs1">Martinez Alonso, Rodney; Plets, David; Martens, Luc; Joseph, Wout; Fontes Pupo, Ernesto; Guillen Nieto, Glauco (1 September 2023). <a rel="nofollow" class="external text" href="https://www.sciencedirect.com/science/article/pii/S138912862300316X">"White spaces pattern finding and inference based on machine learning for multi-frequency spectrum footprints"</a>. <i>Computer Networks</i>. <b>233</b>: 109871. <a href="/wiki/Doi_(identifier)" class="mw-redirect" title="Doi (identifier)">doi</a>:<a rel="nofollow" class="external text" href="https://doi.org/10.1016%2Fj.comnet.2023.109871">10.1016/j.comnet.2023.109871</a>. <a href="/wiki/Hdl_(identifier)" class="mw-redirect" title="Hdl (identifier)">hdl</a>:<span class="id-lock-free" title="Freely accessible"><a rel="nofollow" class="external text" href="https://hdl.handle.net/1854%2FLU-01HGAPQWFZNJYT40GNBAC025PS">1854/LU-01HGAPQWFZNJYT40GNBAC025PS</a></span>. <a href="/wiki/ISSN_(identifier)" class="mw-redirect" title="ISSN (identifier)">ISSN</a> <a rel="nofollow" class="external text" href="https://search.worldcat.org/issn/1389-1286">1389-1286</a>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.genre=article&rft.jtitle=Computer+Networks&rft.atitle=White+spaces+pattern+finding+and+inference+based+on+machine+learning+for+multi-frequency+spectrum+footprints&rft.volume=233&rft.pages=109871&rft.date=2023-09-01&rft_id=info%3Ahdl%2F1854%2FLU-01HGAPQWFZNJYT40GNBAC025PS&rft.issn=1389-1286&rft_id=info%3Adoi%2F10.1016%2Fj.comnet.2023.109871&rft.aulast=Martinez+Alonso&rft.aufirst=Rodney&rft.au=Plets%2C+David&rft.au=Martens%2C+Luc&rft.au=Joseph%2C+Wout&rft.au=Fontes+Pupo%2C+Ernesto&rft.au=Guillen+Nieto%2C+Glauco&rft_id=https%3A%2F%2Fwww.sciencedirect.com%2Fscience%2Farticle%2Fpii%2FS138912862300316X&rfr_id=info%3Asid%2Fen.wikipedia.org%3ACognitive+radio" class="Z3988"></span></span> </li> </ol></div></div> <div class="mw-heading mw-heading2"><h2 id="External_links">External links</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Cognitive_radio&action=edit&section=12" title="Edit section: External links"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <ul><li><a rel="nofollow" class="external text" href="http://bwrc.eecs.berkeley.edu/Research/MCMA/">Berkeley Wireless Research Center Cognitive Radio Workshop</a> – first workshop on cognitive radio; its focus was mainly on research issues within the topic</li> <li><a rel="nofollow" class="external text" href="https://web.archive.org/web/20090217044113/http://www.cognitiveradio.wireless.vt.edu/">Center for Wireless Telecommunications (CWT), Virginia Tech</a></li> <li><a rel="nofollow" class="external text" href="https://web.archive.org/web/20050805081707/http://www.fcc.gov/oet/cognitiveradio/">Cognitive Radio Technologies Proceeding of Federal Communications Commission</a> – Federal Communications Commission rules on cognitive radio</li> <li><a rel="nofollow" class="external text" href="http://www.ieee-dyspan.org/">IEEE DySPAN Conference</a></li></ul>    </div><noscript><img src="https://login.wikimedia.org/wiki/Special:CentralAutoLogin/start?type=1x1&useformat=desktop" alt="" width="1" height="1" style="border: none; position: absolute;"></noscript> <div class="printfooter" data-nosnippet="">Retrieved from "<a dir="ltr" href="https://en.wikipedia.org/w/index.php?title=Cognitive_radio&oldid=1260832972">https://en.wikipedia.org/w/index.php?title=Cognitive_radio&oldid=1260832972</a>"</div></div> <div id="catlinks" class="catlinks" data-mw="interface"><div id="mw-normal-catlinks" class="mw-normal-catlinks"><a href="/wiki/Help:Category" title="Help:Category">Categories</a>: <ul><li><a href="/wiki/Category:Radio_technology" title="Category:Radio technology">Radio technology</a></li><li><a href="/wiki/Category:Wireless_networking" title="Category:Wireless networking">Wireless networking</a></li><li><a href="/wiki/Category:Radio_resource_management" title="Category:Radio resource management">Radio resource management</a></li><li><a href="/wiki/Category:Radiofrequency_receivers" title="Category:Radiofrequency receivers">Radiofrequency receivers</a></li><li><a href="/wiki/Category:Telecommunications_engineering" title="Category:Telecommunications engineering">Telecommunications engineering</a></li></ul></div><div id="mw-hidden-catlinks" class="mw-hidden-catlinks mw-hidden-cats-hidden">Hidden categories: <ul><li><a href="/wiki/Category:Articles_with_short_description" title="Category:Articles with short description">Articles with short description</a></li><li><a href="/wiki/Category:Short_description_is_different_from_Wikidata" title="Category:Short description is different from Wikidata">Short description is different from Wikidata</a></li><li><a href="/wiki/Category:Use_dmy_dates_from_June_2023" title="Category:Use dmy dates from June 2023">Use dmy dates from June 2023</a></li><li><a href="/wiki/Category:All_articles_with_unsourced_statements" title="Category:All articles with unsourced statements">All articles with unsourced statements</a></li><li><a href="/wiki/Category:Articles_with_unsourced_statements_from_January_2009" title="Category:Articles with unsourced statements from January 2009">Articles with unsourced statements from January 2009</a></li></ul></div></div> </div> </main> </div> <div class="mw-footer-container"> <footer id="footer" class="mw-footer" > <ul id="footer-info"> <li id="footer-info-lastmod"> This page was last edited on 2 December 2024, at 21:34<span class="anonymous-show"> (UTC)</span>.</li> <li id="footer-info-copyright">Text is available under the <a href="/wiki/Wikipedia:Text_of_the_Creative_Commons_Attribution-ShareAlike_4.0_International_License" title="Wikipedia:Text of the Creative Commons Attribution-ShareAlike 4.0 International License">Creative Commons Attribution-ShareAlike 4.0 License</a>; additional terms may apply. By using this site, you agree to the <a href="https://foundation.wikimedia.org/wiki/Special:MyLanguage/Policy:Terms_of_Use" class="extiw" title="foundation:Special:MyLanguage/Policy:Terms of Use">Terms of Use</a> and <a href="https://foundation.wikimedia.org/wiki/Special:MyLanguage/Policy:Privacy_policy" class="extiw" title="foundation:Special:MyLanguage/Policy:Privacy policy">Privacy Policy</a>. Wikipedia® is a registered trademark of the <a rel="nofollow" class="external text" href="https://wikimediafoundation.org/">Wikimedia Foundation, Inc.</a>, a non-profit organization.</li> </ul> <ul id="footer-places"> <li id="footer-places-privacy"><a href="https://foundation.wikimedia.org/wiki/Special:MyLanguage/Policy:Privacy_policy">Privacy policy</a></li> <li id="footer-places-about"><a href="/wiki/Wikipedia:About">About Wikipedia</a></li> <li id="footer-places-disclaimers"><a href="/wiki/Wikipedia:General_disclaimer">Disclaimers</a></li> <li id="footer-places-contact"><a href="//en.wikipedia.org/wiki/Wikipedia:Contact_us">Contact Wikipedia</a></li> <li id="footer-places-wm-codeofconduct"><a href="https://foundation.wikimedia.org/wiki/Special:MyLanguage/Policy:Universal_Code_of_Conduct">Code of Conduct</a></li> <li id="footer-places-developers"><a href="https://developer.wikimedia.org">Developers</a></li> <li id="footer-places-statslink"><a href="https://stats.wikimedia.org/#/en.wikipedia.org">Statistics</a></li> <li id="footer-places-cookiestatement"><a href="https://foundation.wikimedia.org/wiki/Special:MyLanguage/Policy:Cookie_statement">Cookie statement</a></li> <li id="footer-places-mobileview"><a href="//en.m.wikipedia.org/w/index.php?title=Cognitive_radio&mobileaction=toggle_view_mobile" class="noprint stopMobileRedirectToggle">Mobile view</a></li> </ul> <ul id="footer-icons" class="noprint"> <li id="footer-copyrightico"><a href="https://wikimediafoundation.org/" class="cdx-button cdx-button--fake-button cdx-button--size-large cdx-button--fake-button--enabled"><img src="/static/images/footer/wikimedia-button.svg" width="84" height="29" alt="Wikimedia Foundation" loading="lazy"></a></li> <li id="footer-poweredbyico"><a href="https://www.mediawiki.org/" class="cdx-button cdx-button--fake-button cdx-button--size-large cdx-button--fake-button--enabled"><img src="/w/resources/assets/poweredby_mediawiki.svg" alt="Powered by MediaWiki" width="88" height="31" loading="lazy"></a></li> </ul> </footer> </div> </div> </div> <div class="vector-settings" id="p-dock-bottom"> <ul></ul> </div><script>(RLQ=window.RLQ||[]).push(function(){mw.config.set({"wgHostname":"mw-web.codfw.main-6dfcdd5ff5-pnxn9","wgBackendResponseTime":158,"wgPageParseReport":{"limitreport":{"cputime":"0.338","walltime":"0.422","ppvisitednodes":{"value":2395,"limit":1000000},"postexpandincludesize":{"value":64665,"limit":2097152},"templateargumentsize":{"value":1841,"limit":2097152},"expansiondepth":{"value":12,"limit":100},"expensivefunctioncount":{"value":3,"limit":500},"unstrip-depth":{"value":1,"limit":20},"unstrip-size":{"value":109418,"limit":5000000},"entityaccesscount":{"value":0,"limit":400},"timingprofile":["100.00% 342.208 1 -total"," 63.75% 218.162 1 Template:Reflist"," 26.88% 91.997 17 Template:Cite_journal"," 20.19% 69.079 1 Template:Citation"," 15.35% 52.518 1 Template:Short_description"," 10.05% 34.383 2 Template:Citation_needed"," 9.07% 31.051 2 Template:Pagetype"," 9.06% 30.998 2 Template:Fix"," 5.86% 20.047 4 Template:Category_handler"," 5.33% 18.247 6 Template:Cite_web"]},"scribunto":{"limitreport-timeusage":{"value":"0.197","limit":"10.000"},"limitreport-memusage":{"value":6082932,"limit":52428800}},"cachereport":{"origin":"mw-web.codfw.main-7c4dcdbb87-k2xwt","timestamp":"20241203100755","ttl":2592000,"transientcontent":false}}});});</script> <script type="application/ld+json">{"@context":"https:\/\/schema.org","@type":"Article","name":"Cognitive radio","url":"https:\/\/en.wikipedia.org\/wiki\/Cognitive_radio","sameAs":"http:\/\/www.wikidata.org\/entity\/Q3235733","mainEntity":"http:\/\/www.wikidata.org\/entity\/Q3235733","author":{"@type":"Organization","name":"Contributors to Wikimedia projects"},"publisher":{"@type":"Organization","name":"Wikimedia Foundation, Inc.","logo":{"@type":"ImageObject","url":"https:\/\/www.wikimedia.org\/static\/images\/wmf-hor-googpub.png"}},"datePublished":"2004-09-20T05:02:46Z","dateModified":"2024-12-02T21:34:32Z","headline":"radio that can be programmed and configured dynamically to use the best wireless channels in its vicinity to avoid user interference and congestion"}</script> </body> </html>