CINXE.COM

Search results for: modulation

<!DOCTYPE html> <html lang="en" dir="ltr"> <head> <!-- Google tag (gtag.js) --> <script async src="https://www.googletagmanager.com/gtag/js?id=G-P63WKM1TM1"></script> <script> window.dataLayer = window.dataLayer || []; function gtag(){dataLayer.push(arguments);} gtag('js', new Date()); gtag('config', 'G-P63WKM1TM1'); </script> <!-- Yandex.Metrika counter --> <script type="text/javascript" > (function(m,e,t,r,i,k,a){m[i]=m[i]||function(){(m[i].a=m[i].a||[]).push(arguments)}; m[i].l=1*new Date(); for (var j = 0; j < document.scripts.length; j++) {if (document.scripts[j].src === r) { return; }} k=e.createElement(t),a=e.getElementsByTagName(t)[0],k.async=1,k.src=r,a.parentNode.insertBefore(k,a)}) (window, document, "script", "https://mc.yandex.ru/metrika/tag.js", "ym"); ym(55165297, "init", { clickmap:false, trackLinks:true, accurateTrackBounce:true, webvisor:false }); </script> <noscript><div><img src="https://mc.yandex.ru/watch/55165297" style="position:absolute; left:-9999px;" alt="" /></div></noscript> <!-- /Yandex.Metrika counter --> <!-- Matomo --> <!-- End Matomo Code --> <title>Search results for: modulation</title> <meta name="description" content="Search results for: modulation"> <meta name="keywords" content="modulation"> <meta name="viewport" content="width=device-width, initial-scale=1, minimum-scale=1, maximum-scale=1, user-scalable=no"> <meta charset="utf-8"> <link href="https://cdn.waset.org/favicon.ico" type="image/x-icon" rel="shortcut icon"> <link href="https://cdn.waset.org/static/plugins/bootstrap-4.2.1/css/bootstrap.min.css" rel="stylesheet"> <link href="https://cdn.waset.org/static/plugins/fontawesome/css/all.min.css" rel="stylesheet"> <link href="https://cdn.waset.org/static/css/site.css?v=150220211555" rel="stylesheet"> </head> <body> <header> <div class="container"> <nav class="navbar navbar-expand-lg navbar-light"> <a class="navbar-brand" href="https://waset.org"> <img src="https://cdn.waset.org/static/images/wasetc.png" alt="Open Science Research Excellence" title="Open Science Research Excellence" /> </a> <button class="d-block d-lg-none navbar-toggler ml-auto" type="button" data-toggle="collapse" data-target="#navbarMenu" aria-controls="navbarMenu" aria-expanded="false" aria-label="Toggle navigation"> <span class="navbar-toggler-icon"></span> </button> <div class="w-100"> <div class="d-none d-lg-flex flex-row-reverse"> <form method="get" action="https://waset.org/search" class="form-inline my-2 my-lg-0"> <input class="form-control mr-sm-2" type="search" placeholder="Search Conferences" value="modulation" name="q" aria-label="Search"> <button class="btn btn-light my-2 my-sm-0" type="submit"><i class="fas fa-search"></i></button> </form> </div> <div class="collapse navbar-collapse mt-1" id="navbarMenu"> <ul class="navbar-nav ml-auto align-items-center" id="mainNavMenu"> <li class="nav-item"> <a class="nav-link" href="https://waset.org/conferences" title="Conferences in 2024/2025/2026">Conferences</a> </li> <li class="nav-item"> <a class="nav-link" href="https://waset.org/disciplines" title="Disciplines">Disciplines</a> </li> <li class="nav-item"> <a class="nav-link" href="https://waset.org/committees" rel="nofollow">Committees</a> </li> <li class="nav-item dropdown"> <a class="nav-link dropdown-toggle" href="#" id="navbarDropdownPublications" role="button" data-toggle="dropdown" aria-haspopup="true" aria-expanded="false"> Publications </a> <div class="dropdown-menu" aria-labelledby="navbarDropdownPublications"> <a class="dropdown-item" href="https://publications.waset.org/abstracts">Abstracts</a> <a class="dropdown-item" href="https://publications.waset.org">Periodicals</a> <a class="dropdown-item" href="https://publications.waset.org/archive">Archive</a> </div> </li> <li class="nav-item"> <a class="nav-link" href="https://waset.org/page/support" title="Support">Support</a> </li> </ul> </div> </div> </nav> </div> </header> <main> <div class="container mt-4"> <div class="row"> <div class="col-md-9 mx-auto"> <form method="get" action="https://publications.waset.org/abstracts/search"> <div id="custom-search-input"> <div class="input-group"> <i class="fas fa-search"></i> <input type="text" class="search-query" name="q" placeholder="Author, Title, Abstract, Keywords" value="modulation"> <input type="submit" class="btn_search" value="Search"> </div> </div> </form> </div> </div> <div class="row mt-3"> <div class="col-sm-3"> <div class="card"> <div class="card-body"><strong>Commenced</strong> in January 2007</div> </div> </div> <div class="col-sm-3"> <div class="card"> <div class="card-body"><strong>Frequency:</strong> Monthly</div> </div> </div> <div class="col-sm-3"> <div class="card"> <div class="card-body"><strong>Edition:</strong> International</div> </div> </div> <div class="col-sm-3"> <div class="card"> <div class="card-body"><strong>Paper Count:</strong> 491</div> </div> </div> </div> <h1 class="mt-3 mb-3 text-center" style="font-size:1.6rem;">Search results for: modulation</h1> <div class="card paper-listing mb-3 mt-3"> <h5 class="card-header" style="font-size:.9rem"><span class="badge badge-info">491</span> Minimization of Switching Losses in Cascaded Multilevel Inverters Using Efficient Sequential Switching Hybrid-Modulation Techniques</h5> <div class="card-body"> <p class="card-text"><strong>Authors:</strong> <a href="https://publications.waset.org/abstracts/search?q=P.%20Satish%20Kumar">P. Satish Kumar</a>, <a href="https://publications.waset.org/abstracts/search?q=K.%20Ramakrishna"> K. Ramakrishna</a>, <a href="https://publications.waset.org/abstracts/search?q=Ch.%20Lokeshwar%20Reddy"> Ch. Lokeshwar Reddy</a>, <a href="https://publications.waset.org/abstracts/search?q=G.%20Sridhar"> G. Sridhar</a> </p> <p class="card-text"><strong>Abstract:</strong></p> This paper presents two different sequential switching hybrid-modulation strategies and implemented for cascaded multilevel inverters. Hybrid modulation strategies represent the combinations of Fundamental-Frequency Pulse Width Modulation (FFPWM) and Multilevel Sinusoidal-Modulation (MSPWM) strategies, and are designed for performance of the well-known Alternative Phase Opposition Disposition (APOD), Phase Shifted Carrier (PSC). The main characteristics of these modulations are the reduction of switching losses with good harmonic performance, balanced power loss dissipation among the devices with in a cell, and among the series-connected cells. The feasibility of these modulations is verified through spectral analysis, power loss analysis and simulation. <p class="card-text"><strong>Keywords:</strong> <a href="https://publications.waset.org/abstracts/search?q=cascaded%20multilevel%20inverters" title="cascaded multilevel inverters">cascaded multilevel inverters</a>, <a href="https://publications.waset.org/abstracts/search?q=hybrid%20modulation" title=" hybrid modulation"> hybrid modulation</a>, <a href="https://publications.waset.org/abstracts/search?q=power%20loss%20analysis" title=" power loss analysis"> power loss analysis</a>, <a href="https://publications.waset.org/abstracts/search?q=pulse%20width%20modulation" title=" pulse width modulation"> pulse width modulation</a> </p> <a href="https://publications.waset.org/abstracts/7094/minimization-of-switching-losses-in-cascaded-multilevel-inverters-using-efficient-sequential-switching-hybrid-modulation-techniques" class="btn btn-primary btn-sm">Procedia</a> <a href="https://publications.waset.org/abstracts/7094.pdf" target="_blank" class="btn btn-primary btn-sm">PDF</a> <span class="bg-info text-light px-1 py-1 float-right rounded"> Downloads <span class="badge badge-light">536</span> </span> </div> </div> <div class="card paper-listing mb-3 mt-3"> <h5 class="card-header" style="font-size:.9rem"><span class="badge badge-info">490</span> Frequency Modulation in Vibro-Acoustic Modulation Method</h5> <div class="card-body"> <p class="card-text"><strong>Authors:</strong> <a href="https://publications.waset.org/abstracts/search?q=D.%20Liu">D. Liu</a>, <a href="https://publications.waset.org/abstracts/search?q=D.%20M.%20Donskoy"> D. M. Donskoy</a> </p> <p class="card-text"><strong>Abstract:</strong></p> The vibroacoustic modulation method is based on the modulation effect of high-frequency ultrasonic wave (carrier) by low-frequency vibration in the presence of various defects, primarily contact-type such as cracks, delamination, etc. The presence and severity of the defect are measured by the ratio of the spectral sidebands and the carrier in the spectrum of the modulated signal. This approach, however, does not differentiate between amplitude and frequency modulations, AM and FM, respectfully. It was experimentally shown that both modulations could be present in the spectrum, yet each modulation may be associated with different physical mechanisms. AM mechanisms are quite well understood and widely covered in the literature. This paper is a first attempt to explain the generation mechanisms of FM and its correlation with the flaw properties. Here we proposed two possible mechanisms leading to FM modulation based on nonlinear local defect resonance and dynamic acousto-elastic models. <p class="card-text"><strong>Keywords:</strong> <a href="https://publications.waset.org/abstracts/search?q=non-destructive%20testing" title="non-destructive testing">non-destructive testing</a>, <a href="https://publications.waset.org/abstracts/search?q=nonlinear%20acoustics" title=" nonlinear acoustics"> nonlinear acoustics</a>, <a href="https://publications.waset.org/abstracts/search?q=structural%20health%20monitoring" title=" structural health monitoring"> structural health monitoring</a>, <a href="https://publications.waset.org/abstracts/search?q=acousto-elasticity" title=" acousto-elasticity"> acousto-elasticity</a>, <a href="https://publications.waset.org/abstracts/search?q=local%20defect%20resonance" title=" local defect resonance"> local defect resonance</a> </p> <a href="https://publications.waset.org/abstracts/149507/frequency-modulation-in-vibro-acoustic-modulation-method" class="btn btn-primary btn-sm">Procedia</a> <a href="https://publications.waset.org/abstracts/149507.pdf" target="_blank" class="btn btn-primary btn-sm">PDF</a> <span class="bg-info text-light px-1 py-1 float-right rounded"> Downloads <span class="badge badge-light">152</span> </span> </div> </div> <div class="card paper-listing mb-3 mt-3"> <h5 class="card-header" style="font-size:.9rem"><span class="badge badge-info">489</span> Experimental Demonstration of an Ultra-Low Power Vertical-Cavity Surface-Emitting Laser for Optical Power Generation</h5> <div class="card-body"> <p class="card-text"><strong>Authors:</strong> <a href="https://publications.waset.org/abstracts/search?q=S.%20Nazhan">S. Nazhan</a>, <a href="https://publications.waset.org/abstracts/search?q=Hassan%20K.%20Al-Musawi"> Hassan K. Al-Musawi</a>, <a href="https://publications.waset.org/abstracts/search?q=Khalid%20A.%20Humood"> Khalid A. Humood</a> </p> <p class="card-text"><strong>Abstract:</strong></p> This paper reports on an experimental investigation into the influence of current modulation on the properties of a vertical-cavity surface-emitting laser (VCSEL) with a direct square wave modulation. The optical output power response, as a function of the pumping current, modulation frequency, and amplitude, is measured for an 850 nm VCSEL. We demonstrate that modulation frequency and amplitude play important roles in reducing the VCSEL&rsquo;s power consumption for optical generation. Indeed, even when the biasing current is below the static threshold, the VCSEL emits optical power under the square wave modulation. The power consumed by the device to generate light is significantly reduced to &gt; 50%, which is below the threshold current, in response to both the modulation frequency and amplitude. An operating VCSEL device at low power is very desirable for less thermal effects, which are essential for a high-speed modulation bandwidth. <p class="card-text"><strong>Keywords:</strong> <a href="https://publications.waset.org/abstracts/search?q=vertical-cavity%20surface-emitting%20lasers" title="vertical-cavity surface-emitting lasers">vertical-cavity surface-emitting lasers</a>, <a href="https://publications.waset.org/abstracts/search?q=VCSELs" title=" VCSELs"> VCSELs</a>, <a href="https://publications.waset.org/abstracts/search?q=optical%20power%20generation" title=" optical power generation"> optical power generation</a>, <a href="https://publications.waset.org/abstracts/search?q=power%20consumption" title=" power consumption"> power consumption</a>, <a href="https://publications.waset.org/abstracts/search?q=square%20wave%20modulation" title=" square wave modulation"> square wave modulation</a> </p> <a href="https://publications.waset.org/abstracts/123396/experimental-demonstration-of-an-ultra-low-power-vertical-cavity-surface-emitting-laser-for-optical-power-generation" class="btn btn-primary btn-sm">Procedia</a> <a href="https://publications.waset.org/abstracts/123396.pdf" target="_blank" class="btn btn-primary btn-sm">PDF</a> <span class="bg-info text-light px-1 py-1 float-right rounded"> Downloads <span class="badge badge-light">165</span> </span> </div> </div> <div class="card paper-listing mb-3 mt-3"> <h5 class="card-header" style="font-size:.9rem"><span class="badge badge-info">488</span> Vibroacoustic Modulation with Chirp Signal</h5> <div class="card-body"> <p class="card-text"><strong>Authors:</strong> <a href="https://publications.waset.org/abstracts/search?q=Dong%20Liu">Dong Liu</a> </p> <p class="card-text"><strong>Abstract:</strong></p> By sending a high-frequency probe wave and a low-frequency pump wave to a specimen, the vibroacoustic method evaluates the defect鈥檚 severity according to the modulation index of the received signal. Many studies experimentally proved the significant sensitivity of the modulation index to the tiny contact type defect. However, it has also been found that the modulation index was highly affected by the frequency of probe or pump waves. Therefore, the chirp signal has been introduced to the VAM method since it can assess multiple frequencies in a relatively short time duration, so the robustness of the VAM method could be enhanced. Consequently, the signal processing method needs to be modified accordingly. Various studies utilized different algorithms or combinations of algorithms for processing the VAM signal method by chirp excitation. These signal process methods were compared and used for processing a VAM signal acquired from the steel samples. <p class="card-text"><strong>Keywords:</strong> <a href="https://publications.waset.org/abstracts/search?q=vibroacoustic%20modulation" title="vibroacoustic modulation">vibroacoustic modulation</a>, <a href="https://publications.waset.org/abstracts/search?q=nonlinear%20acoustic%20modulation" title=" nonlinear acoustic modulation"> nonlinear acoustic modulation</a>, <a href="https://publications.waset.org/abstracts/search?q=nonlinear%20acoustic%20NDT%26E" title=" nonlinear acoustic NDT&amp;E"> nonlinear acoustic NDT&amp;E</a>, <a href="https://publications.waset.org/abstracts/search?q=signal%20processing" title=" signal processing"> signal processing</a>, <a href="https://publications.waset.org/abstracts/search?q=structural%20health%20monitoring" title=" structural health monitoring"> structural health monitoring</a> </p> <a href="https://publications.waset.org/abstracts/155764/vibroacoustic-modulation-with-chirp-signal" class="btn btn-primary btn-sm">Procedia</a> <a href="https://publications.waset.org/abstracts/155764.pdf" target="_blank" class="btn btn-primary btn-sm">PDF</a> <span class="bg-info text-light px-1 py-1 float-right rounded"> Downloads <span class="badge badge-light">99</span> </span> </div> </div> <div class="card paper-listing mb-3 mt-3"> <h5 class="card-header" style="font-size:.9rem"><span class="badge badge-info">487</span> Dynamics of Chirped RZ Modulation Format in GEPON Fiber to the Home (FTTH) Network </h5> <div class="card-body"> <p class="card-text"><strong>Authors:</strong> <a href="https://publications.waset.org/abstracts/search?q=Anurag%20Sharma">Anurag Sharma</a>, <a href="https://publications.waset.org/abstracts/search?q=Manoj%20Kumar"> Manoj Kumar</a>, <a href="https://publications.waset.org/abstracts/search?q=Ashima"> Ashima</a>, <a href="https://publications.waset.org/abstracts/search?q=Sooraj%20Parkash"> Sooraj Parkash</a> </p> <p class="card-text"><strong>Abstract:</strong></p> The work in this paper presents simulative comparison for different modulation formats such as NRZ, Manchester and CRZ in a 100 subscribers at 5 Gbps bit rate Gigabit Ethernet Passive Optical Network (GEPON) FTTH network. It is observed from the simulation results that the CRZ modulation format is best suited for the designed system. A link design for 1:100 splitter is used as Passive Optical Network (PON) element which creates communication between central offices to different users. The Bit Error Rate (BER) is found to be 2.8535e-10 at 5 Gbit/s systems for CRZ modulation format. <p class="card-text"><strong>Keywords:</strong> <a href="https://publications.waset.org/abstracts/search?q=PON" title="PON ">PON </a>, <a href="https://publications.waset.org/abstracts/search?q=FTTH" title=" FTTH"> FTTH</a>, <a href="https://publications.waset.org/abstracts/search?q=OLT" title=" OLT"> OLT</a>, <a href="https://publications.waset.org/abstracts/search?q=ONU" title=" ONU"> ONU</a>, <a href="https://publications.waset.org/abstracts/search?q=CO" title=" CO"> CO</a>, <a href="https://publications.waset.org/abstracts/search?q=GEPON" title=" GEPON"> GEPON</a> </p> <a href="https://publications.waset.org/abstracts/28883/dynamics-of-chirped-rz-modulation-format-in-gepon-fiber-to-the-home-ftth-network" class="btn btn-primary btn-sm">Procedia</a> <a href="https://publications.waset.org/abstracts/28883.pdf" target="_blank" class="btn btn-primary btn-sm">PDF</a> <span class="bg-info text-light px-1 py-1 float-right rounded"> Downloads <span class="badge badge-light">704</span> </span> </div> </div> <div class="card paper-listing mb-3 mt-3"> <h5 class="card-header" style="font-size:.9rem"><span class="badge badge-info">486</span> Differential Signaling Spread-Spectrum Modulation of the In-Door LED Visible Light Wireless Communications using Mobile-Phone Camera</h5> <div class="card-body"> <p class="card-text"><strong>Authors:</strong> <a href="https://publications.waset.org/abstracts/search?q=Shih-Hao%20Chen">Shih-Hao Chen</a>, <a href="https://publications.waset.org/abstracts/search?q=Chi-Wai%20Chow"> Chi-Wai Chow</a> </p> <p class="card-text"><strong>Abstract:</strong></p> Visible light communication combined with spread spectrum modulation is demonstrated in this study. Differential signaling method also ensures the proposed system that can support high immunity to ambient light interference. Experiment result shows the proposed system has 6 dB gain comparing with the original On-Off Keying modulation scheme. <p class="card-text"><strong>Keywords:</strong> <a href="https://publications.waset.org/abstracts/search?q=Visible%20Light%20Communication%20%28VLC%29" title="Visible Light Communication (VLC)">Visible Light Communication (VLC)</a>, <a href="https://publications.waset.org/abstracts/search?q=Spread%20Spectrum%20Modulation%20%28SSM%29" title=" Spread Spectrum Modulation (SSM)"> Spread Spectrum Modulation (SSM)</a>, <a href="https://publications.waset.org/abstracts/search?q=On-Off%20Keying" title=" On-Off Keying"> On-Off Keying</a>, <a href="https://publications.waset.org/abstracts/search?q=visible%20light%20communication" title=" visible light communication "> visible light communication </a> </p> <a href="https://publications.waset.org/abstracts/15447/differential-signaling-spread-spectrum-modulation-of-the-in-door-led-visible-light-wireless-communications-using-mobile-phone-camera" class="btn btn-primary btn-sm">Procedia</a> <a href="https://publications.waset.org/abstracts/15447.pdf" target="_blank" class="btn btn-primary btn-sm">PDF</a> <span class="bg-info text-light px-1 py-1 float-right rounded"> Downloads <span class="badge badge-light">522</span> </span> </div> </div> <div class="card paper-listing mb-3 mt-3"> <h5 class="card-header" style="font-size:.9rem"><span class="badge badge-info">485</span> ICanny: CNN Modulation Recognition Algorithm</h5> <div class="card-body"> <p class="card-text"><strong>Authors:</strong> <a href="https://publications.waset.org/abstracts/search?q=Jingpeng%20Gao">Jingpeng Gao</a>, <a href="https://publications.waset.org/abstracts/search?q=Xinrui%20Mao"> Xinrui Mao</a>, <a href="https://publications.waset.org/abstracts/search?q=Zhibin%20Deng"> Zhibin Deng</a> </p> <p class="card-text"><strong>Abstract:</strong></p> Aiming at the low recognition rate on the composite signal modulation in low signal to noise ratio (SNR), this paper proposes a modulation recognition algorithm based on ICanny-CNN. Firstly, the radar signal is transformed into the time-frequency image by Choi-Williams Distribution (CWD). Secondly, we propose an image processing algorithm using the Guided Filter and the threshold selection method, which is combined with the hole filling and the mask operation. Finally, the shallow convolutional neural network (CNN) is combined with the idea of the depth-wise convolution (Dw Conv) and the point-wise convolution (Pw Conv). The proposed CNN is designed to complete image classification and realize modulation recognition of radar signal. The simulation results show that the proposed algorithm can reach 90.83% at 0dB and 71.52% at -8dB. Therefore, the proposed algorithm has a good classification and anti-noise performance in radar signal modulation recognition and other fields. <p class="card-text"><strong>Keywords:</strong> <a href="https://publications.waset.org/abstracts/search?q=modulation%20recognition" title="modulation recognition">modulation recognition</a>, <a href="https://publications.waset.org/abstracts/search?q=image%20processing" title=" image processing"> image processing</a>, <a href="https://publications.waset.org/abstracts/search?q=composite%20signal" title=" composite signal"> composite signal</a>, <a href="https://publications.waset.org/abstracts/search?q=improved%20Canny%20algorithm" title=" improved Canny algorithm"> improved Canny algorithm</a> </p> <a href="https://publications.waset.org/abstracts/139350/icanny-cnn-modulation-recognition-algorithm" class="btn btn-primary btn-sm">Procedia</a> <a href="https://publications.waset.org/abstracts/139350.pdf" target="_blank" class="btn btn-primary btn-sm">PDF</a> <span class="bg-info text-light px-1 py-1 float-right rounded"> Downloads <span class="badge badge-light">191</span> </span> </div> </div> <div class="card paper-listing mb-3 mt-3"> <h5 class="card-header" style="font-size:.9rem"><span class="badge badge-info">484</span> Hybrid PWM Techniques for the Reduction of Switching Losses and Voltage Harmonics in Cascaded Multilevel Inverters</h5> <div class="card-body"> <p class="card-text"><strong>Authors:</strong> <a href="https://publications.waset.org/abstracts/search?q=Venkata%20Reddy%20Kota">Venkata Reddy Kota</a> </p> <p class="card-text"><strong>Abstract:</strong></p> These days, the industrial trend is moving away from heavy and bulky passive components to power converter systems that use more and more semiconductor elements. Also, it is difficult to connect the traditional converters to the high and medium voltage. For these reasons, a new family of multilevel inverters has appeared as a solution for working with higher voltage levels. Different modulation topologies like Sinusoidal Pulse Width Modulation (SPWM), Selective Harmonic Elimination Pulse Width Modulation (SHE-PWM) are available for multilevel inverters. In this work, different hybrid modulation techniques which are combination of fundamental frequency modulation and multilevel sinusoidal-modulation are compared. The main characteristic of these modulations are reduction of switching losses with good harmonic performance and balanced power loss dissipation among the device. The proposed hybrid modulation schemes are developed and simulated in Matlab/Simulink for cascaded H-bridge inverter. The results validate the applicability of the proposed schemes for cascaded multilevel inverter. <p class="card-text"><strong>Keywords:</strong> <a href="https://publications.waset.org/abstracts/search?q=hybrid%20PWM%20techniques" title="hybrid PWM techniques">hybrid PWM techniques</a>, <a href="https://publications.waset.org/abstracts/search?q=cascaded%20multilevel%20inverters" title=" cascaded multilevel inverters"> cascaded multilevel inverters</a>, <a href="https://publications.waset.org/abstracts/search?q=switching%20loss%20minimization" title=" switching loss minimization"> switching loss minimization</a> </p> <a href="https://publications.waset.org/abstracts/12634/hybrid-pwm-techniques-for-the-reduction-of-switching-losses-and-voltage-harmonics-in-cascaded-multilevel-inverters" class="btn btn-primary btn-sm">Procedia</a> <a href="https://publications.waset.org/abstracts/12634.pdf" target="_blank" class="btn btn-primary btn-sm">PDF</a> <span class="bg-info text-light px-1 py-1 float-right rounded"> Downloads <span class="badge badge-light">616</span> </span> </div> </div> <div class="card paper-listing mb-3 mt-3"> <h5 class="card-header" style="font-size:.9rem"><span class="badge badge-info">483</span> Efficient Variable Modulation Scheme Based on Codebook in the MIMO-OFDM System</h5> <div class="card-body"> <p class="card-text"><strong>Authors:</strong> <a href="https://publications.waset.org/abstracts/search?q=Yong-Jun%20Kim">Yong-Jun Kim</a>, <a href="https://publications.waset.org/abstracts/search?q=Jae-Hyun%20Ro"> Jae-Hyun Ro</a>, <a href="https://publications.waset.org/abstracts/search?q=Chang-Bin%20Ha"> Chang-Bin Ha</a>, <a href="https://publications.waset.org/abstracts/search?q=Hyoung-Kyu%20Song"> Hyoung-Kyu Song</a> </p> <p class="card-text"><strong>Abstract:</strong></p> Because current wireless communication requires high reliability in a limited bandwidth environment, this paper proposes the variable modulation scheme based on the codebook. The variable modulation scheme adjusts transmission power using the codebook in accordance with hannel state. Also, if the codebook is composed of many bits, the reliability is more improved by the proposed scheme. The simulation results show that the performance of proposed scheme has better reliability than the the performance of conventional scheme. <p class="card-text"><strong>Keywords:</strong> <a href="https://publications.waset.org/abstracts/search?q=MIMO-OFDM" title="MIMO-OFDM">MIMO-OFDM</a>, <a href="https://publications.waset.org/abstracts/search?q=variable%20modulation" title=" variable modulation"> variable modulation</a>, <a href="https://publications.waset.org/abstracts/search?q=codebook" title=" codebook"> codebook</a>, <a href="https://publications.waset.org/abstracts/search?q=channel%20state" title=" channel state"> channel state</a> </p> <a href="https://publications.waset.org/abstracts/33079/efficient-variable-modulation-scheme-based-on-codebook-in-the-mimo-ofdm-system" class="btn btn-primary btn-sm">Procedia</a> <a href="https://publications.waset.org/abstracts/33079.pdf" target="_blank" class="btn btn-primary btn-sm">PDF</a> <span class="bg-info text-light px-1 py-1 float-right rounded"> Downloads <span class="badge badge-light">587</span> </span> </div> </div> <div class="card paper-listing mb-3 mt-3"> <h5 class="card-header" style="font-size:.9rem"><span class="badge badge-info">482</span> Application of Strong Optical Feedback to Enhance the Modulation Bandwidth of Semiconductor Lasers to the Millimeter-Wave Band</h5> <div class="card-body"> <p class="card-text"><strong>Authors:</strong> <a href="https://publications.waset.org/abstracts/search?q=Moustafa%20Ahmed">Moustafa Ahmed</a>, <a href="https://publications.waset.org/abstracts/search?q=Ahmed%20Bakry"> Ahmed Bakry</a>, <a href="https://publications.waset.org/abstracts/search?q=Fumio%20Koyama"> Fumio Koyama</a> </p> <p class="card-text"><strong>Abstract:</strong></p> We report on the use of strong external optical feedback to enhance the modulation response of semiconductor lasers over a frequency passband around modulation frequencies higher than 60 GHz. We show that this modulation enhancement is a type of photon-photon resonance (PPR) of oscillating modes in the external cavity formed between the laser and the external reflector. The study is based on a time-delay rate equation model that takes into account both the strong feedback and multiple reflections in the external cavity. We examine the harmonic and intermodulation distortions associated with single and two-tone modulations in the mm-wave band of the resonant modulation. We show that compared with solitary lasers modulated around the carrier-photon resonance frequency, the present mm-wave modulated signal has lower distortions. <p class="card-text"><strong>Keywords:</strong> <a href="https://publications.waset.org/abstracts/search?q=semiconductor%20laser" title="semiconductor laser">semiconductor laser</a>, <a href="https://publications.waset.org/abstracts/search?q=optical%20feedback" title=" optical feedback"> optical feedback</a>, <a href="https://publications.waset.org/abstracts/search?q=modulation" title=" modulation"> modulation</a>, <a href="https://publications.waset.org/abstracts/search?q=harmonic%20distortion" title=" harmonic distortion"> harmonic distortion</a> </p> <a href="https://publications.waset.org/abstracts/10588/application-of-strong-optical-feedback-to-enhance-the-modulation-bandwidth-of-semiconductor-lasers-to-the-millimeter-wave-band" class="btn btn-primary btn-sm">Procedia</a> <a href="https://publications.waset.org/abstracts/10588.pdf" target="_blank" class="btn btn-primary btn-sm">PDF</a> <span class="bg-info text-light px-1 py-1 float-right rounded"> Downloads <span class="badge badge-light">747</span> </span> </div> </div> <div class="card paper-listing mb-3 mt-3"> <h5 class="card-header" style="font-size:.9rem"><span class="badge badge-info">481</span> Implementation of Multi-Carrier Pulse Width Modulation Techniques in Multilevel Inverter</h5> <div class="card-body"> <p class="card-text"><strong>Authors:</strong> <a href="https://publications.waset.org/abstracts/search?q=M.%20Suresh%20Kumar">M. Suresh Kumar</a>, <a href="https://publications.waset.org/abstracts/search?q=K.%20Ramani"> K. Ramani</a> </p> <p class="card-text"><strong>Abstract:</strong></p> This paper proposed the Multi-Carrier Pulse Width Modulation for the minimization of Total Harmonic Distortion in Cascaded H-Bridge Multi-Level Inverter. Multicarrier Pulse Width Modulation method uses Alternate Position of Disposition scheme to determine the appropriate switching angle to Multi-Level Inverter. In this paper simulation results shows that the validation of Multi-Carrier Pulse Width Modulation method does capably eliminate a great number of precise harmonics and minimize the Total Harmonic Distortion value in output voltage waveform. <p class="card-text"><strong>Keywords:</strong> <a href="https://publications.waset.org/abstracts/search?q=alternate%20position" title="alternate position">alternate position</a>, <a href="https://publications.waset.org/abstracts/search?q=fast%20fourier%20analysis" title=" fast fourier analysis"> fast fourier analysis</a>, <a href="https://publications.waset.org/abstracts/search?q=multi-carrier%20pulse%20width%20modulation" title=" multi-carrier pulse width modulation"> multi-carrier pulse width modulation</a>, <a href="https://publications.waset.org/abstracts/search?q=multi-level%20inverter" title=" multi-level inverter"> multi-level inverter</a>, <a href="https://publications.waset.org/abstracts/search?q=total%20harmonic%20distortion" title=" total harmonic distortion"> total harmonic distortion</a> </p> <a href="https://publications.waset.org/abstracts/31826/implementation-of-multi-carrier-pulse-width-modulation-techniques-in-multilevel-inverter" class="btn btn-primary btn-sm">Procedia</a> <a href="https://publications.waset.org/abstracts/31826.pdf" target="_blank" class="btn btn-primary btn-sm">PDF</a> <span class="bg-info text-light px-1 py-1 float-right rounded"> Downloads <span class="badge badge-light">647</span> </span> </div> </div> <div class="card paper-listing mb-3 mt-3"> <h5 class="card-header" style="font-size:.9rem"><span class="badge badge-info">480</span> Cooperative CDD scheme Based on Adaptive Modulation in Wireless Communiation System</h5> <div class="card-body"> <p class="card-text"><strong>Authors:</strong> <a href="https://publications.waset.org/abstracts/search?q=Seung-Jun%20Yu">Seung-Jun Yu</a>, <a href="https://publications.waset.org/abstracts/search?q=Hwan-Jun%20Choi"> Hwan-Jun Choi</a>, <a href="https://publications.waset.org/abstracts/search?q=Hyoung-Kyu%20Song"> Hyoung-Kyu Song</a> </p> <p class="card-text"><strong>Abstract:</strong></p> Among spatial diversity scheme, orthogonal space-time block code (OSTBC) and cyclic delay diversity (CDD) have been widely studied for the cooperative wireless relaying system. However, conventional OSTBC and CDD cannot cope with change in the number of relays owing to low throughput or error performance. In this paper, we propose a cooperative cyclic delay diversity (CDD) scheme that use hierarchical modulation at the source and adaptive modulation based on cyclic redundancy check (CRC) code at the relays. <p class="card-text"><strong>Keywords:</strong> <a href="https://publications.waset.org/abstracts/search?q=adaptive%20modulation" title="adaptive modulation">adaptive modulation</a>, <a href="https://publications.waset.org/abstracts/search?q=cooperative%20communication" title=" cooperative communication"> cooperative communication</a>, <a href="https://publications.waset.org/abstracts/search?q=CDD" title=" CDD"> CDD</a>, <a href="https://publications.waset.org/abstracts/search?q=OSTBC" title=" OSTBC"> OSTBC</a> </p> <a href="https://publications.waset.org/abstracts/3513/cooperative-cdd-scheme-based-on-adaptive-modulation-in-wireless-communiation-system" class="btn btn-primary btn-sm">Procedia</a> <a href="https://publications.waset.org/abstracts/3513.pdf" target="_blank" class="btn btn-primary btn-sm">PDF</a> <span class="bg-info text-light px-1 py-1 float-right rounded"> Downloads <span class="badge badge-light">431</span> </span> </div> </div> <div class="card paper-listing mb-3 mt-3"> <h5 class="card-header" style="font-size:.9rem"><span class="badge badge-info">479</span> Adaptive Transmission Scheme Based on Channel State in Dual-Hop System</h5> <div class="card-body"> <p class="card-text"><strong>Authors:</strong> <a href="https://publications.waset.org/abstracts/search?q=Seung-Jun%20Yu">Seung-Jun Yu</a>, <a href="https://publications.waset.org/abstracts/search?q=Yong-Jun%20Kim"> Yong-Jun Kim</a>, <a href="https://publications.waset.org/abstracts/search?q=Jung-In%20Baik"> Jung-In Baik</a>, <a href="https://publications.waset.org/abstracts/search?q=Hyoung-Kyu%20Song"> Hyoung-Kyu Song</a> </p> <p class="card-text"><strong>Abstract:</strong></p> In this paper, a dual-hop relay based on channel state is studied. In the conventional relay scheme, a relay uses the same modulation method without reference to channel state. But, a relay uses an adaptive modulation method with reference to channel state. If the channel state is poor, a relay eliminates latter 2 bits and uses Quadrature Phase Shift Keying (QPSK) modulation. If channel state is good, a relay modulates the received symbols with 16-QAM symbols by using 4 bits. The performance of the proposed scheme for Symbol Error Rate (SER) and throughput is analyzed. <p class="card-text"><strong>Keywords:</strong> <a href="https://publications.waset.org/abstracts/search?q=adaptive%20transmission" title="adaptive transmission">adaptive transmission</a>, <a href="https://publications.waset.org/abstracts/search?q=channel%20state" title=" channel state"> channel state</a>, <a href="https://publications.waset.org/abstracts/search?q=dual-hop" title=" dual-hop"> dual-hop</a>, <a href="https://publications.waset.org/abstracts/search?q=hierarchical%20modulation" title=" hierarchical modulation"> hierarchical modulation</a>, <a href="https://publications.waset.org/abstracts/search?q=relay" title=" relay"> relay</a> </p> <a href="https://publications.waset.org/abstracts/52599/adaptive-transmission-scheme-based-on-channel-state-in-dual-hop-system" class="btn btn-primary btn-sm">Procedia</a> <a href="https://publications.waset.org/abstracts/52599.pdf" target="_blank" class="btn btn-primary btn-sm">PDF</a> <span class="bg-info text-light px-1 py-1 float-right rounded"> Downloads <span class="badge badge-light">380</span> </span> </div> </div> <div class="card paper-listing mb-3 mt-3"> <h5 class="card-header" style="font-size:.9rem"><span class="badge badge-info">478</span> Analysis of Different Space Vector Pulse Width Modulation Techniques for a Five-Phase Inverter</h5> <div class="card-body"> <p class="card-text"><strong>Authors:</strong> <a href="https://publications.waset.org/abstracts/search?q=K.%20A.%20Chinmaya">K. A. Chinmaya</a>, <a href="https://publications.waset.org/abstracts/search?q=M.%20Udaya%20Bhaskar"> M. Udaya Bhaskar</a> </p> <p class="card-text"><strong>Abstract:</strong></p> Multiphase motor drives are now a day considered for numerous applications due to the advantages that they offer when compared to their three-phase counterparts. Proper modeling of inverters and motors are important in devising an appropriate control algorithm. This paper develops a complete modeling of a five-phase inverter and five-phase space vector modulation schemes which can be used for five-phase motor drives. A novel modified algorithm is introduced which enables the sinusoidal output voltages up to certain voltage value. The waveforms of phase to neutral voltage are compared with the different modulation techniques and also different modulation indexes in terms of Low-order Harmonic (LH) voltage of 3rd and 7th present. A detailed performance evolution of existing and newly modified schemes is done in terms of Total Harmonic Distortion (THD). <p class="card-text"><strong>Keywords:</strong> <a href="https://publications.waset.org/abstracts/search?q=multi-phase%20drives" title="multi-phase drives">multi-phase drives</a>, <a href="https://publications.waset.org/abstracts/search?q=space%20vector%20modulation" title=" space vector modulation"> space vector modulation</a>, <a href="https://publications.waset.org/abstracts/search?q=voltage%20source%20inverter" title=" voltage source inverter"> voltage source inverter</a>, <a href="https://publications.waset.org/abstracts/search?q=low%20order%20harmonic%20voltages" title=" low order harmonic voltages"> low order harmonic voltages</a>, <a href="https://publications.waset.org/abstracts/search?q=total%20harmonic%20distortion" title=" total harmonic distortion"> total harmonic distortion</a> </p> <a href="https://publications.waset.org/abstracts/8307/analysis-of-different-space-vector-pulse-width-modulation-techniques-for-a-five-phase-inverter" class="btn btn-primary btn-sm">Procedia</a> <a href="https://publications.waset.org/abstracts/8307.pdf" target="_blank" class="btn btn-primary btn-sm">PDF</a> <span class="bg-info text-light px-1 py-1 float-right rounded"> Downloads <span class="badge badge-light">404</span> </span> </div> </div> <div class="card paper-listing mb-3 mt-3"> <h5 class="card-header" style="font-size:.9rem"><span class="badge badge-info">477</span> A Comparative Analysis of Multicarrier SPWM Strategies for Five-Level Flying Capacitor Inverter</h5> <div class="card-body"> <p class="card-text"><strong>Authors:</strong> <a href="https://publications.waset.org/abstracts/search?q=Bachir%20Belmadani">Bachir Belmadani</a>, <a href="https://publications.waset.org/abstracts/search?q=Rachid%20Taleb"> Rachid Taleb</a>, <a href="https://publications.waset.org/abstracts/search?q=Zinelaabidine%20Boudjema"> Zinelaabidine Boudjema</a>, <a href="https://publications.waset.org/abstracts/search?q=Adil%20Yahdou"> Adil Yahdou</a> </p> <p class="card-text"><strong>Abstract:</strong></p> Carrier-based methods have been used widely for switching of multilevel inverters due to their simplicity, flexibility and reduced computational requirements compared to space vector modulation (SVM). This paper focuses on Multicarrier Sinusoidal Pulse Width Modulation (MCSPWM) strategy for the three phase Five-Level Flying Capacitor Inverter (5LFCI). The inverter is simulated for Induction Motor (IM) load and Total Harmonic Distortion (THD) for output waveforms is observed for different controlling schemes. <p class="card-text"><strong>Keywords:</strong> <a href="https://publications.waset.org/abstracts/search?q=flying%20capacitor%20inverter" title="flying capacitor inverter">flying capacitor inverter</a>, <a href="https://publications.waset.org/abstracts/search?q=multicarrier%20sinusoidal%20pulse%20width%20modulation" title=" multicarrier sinusoidal pulse width modulation"> multicarrier sinusoidal pulse width modulation</a>, <a href="https://publications.waset.org/abstracts/search?q=space%20vector%20modulation" title=" space vector modulation"> space vector modulation</a>, <a href="https://publications.waset.org/abstracts/search?q=total%20harmonic%20distortion" title=" total harmonic distortion"> total harmonic distortion</a>, <a href="https://publications.waset.org/abstracts/search?q=induction%20motor" title=" induction motor"> induction motor</a> </p> <a href="https://publications.waset.org/abstracts/45816/a-comparative-analysis-of-multicarrier-spwm-strategies-for-five-level-flying-capacitor-inverter" class="btn btn-primary btn-sm">Procedia</a> <a href="https://publications.waset.org/abstracts/45816.pdf" target="_blank" class="btn btn-primary btn-sm">PDF</a> <span class="bg-info text-light px-1 py-1 float-right rounded"> Downloads <span class="badge badge-light">410</span> </span> </div> </div> <div class="card paper-listing mb-3 mt-3"> <h5 class="card-header" style="font-size:.9rem"><span class="badge badge-info">476</span> Magneto-Solutal Convection in Newtonian Fluid Layer with Modulated Gravity</h5> <div class="card-body"> <p class="card-text"><strong>Authors:</strong> <a href="https://publications.waset.org/abstracts/search?q=Om%20Prakash%20Keshri">Om Prakash Keshri</a>, <a href="https://publications.waset.org/abstracts/search?q=Anand%20Kumar"> Anand Kumar</a>, <a href="https://publications.waset.org/abstracts/search?q=Vinod%20K.%20Gupta"> Vinod K. Gupta</a> </p> <p class="card-text"><strong>Abstract:</strong></p> In the present study, the effect of gravity modulation on the onset of convection in viscous fluid layer under the influence of induced magnetic field, salted from above on the boundaries, has been investigated. Linear and nonlinear stability analysis has been performed. A linear stability analysis is performed to show that the gravity modulation can significantly affect the stability limits of the system. A method based on small amplitude of the modulation is used to compute the critical value of Rayleigh number and wave number. The effect of Smith number, salute Rayleigh number and magnetic Prandtl number on the stability of the system is investigated. <p class="card-text"><strong>Keywords:</strong> <a href="https://publications.waset.org/abstracts/search?q=viscous%20fluid" title="viscous fluid">viscous fluid</a>, <a href="https://publications.waset.org/abstracts/search?q=induced%20magnetic%20field" title=" induced magnetic field"> induced magnetic field</a>, <a href="https://publications.waset.org/abstracts/search?q=gravity%20modulation" title=" gravity modulation"> gravity modulation</a>, <a href="https://publications.waset.org/abstracts/search?q=salute%20convection" title=" salute convection"> salute convection</a> </p> <a href="https://publications.waset.org/abstracts/98873/magneto-solutal-convection-in-newtonian-fluid-layer-with-modulated-gravity" class="btn btn-primary btn-sm">Procedia</a> <a href="https://publications.waset.org/abstracts/98873.pdf" target="_blank" class="btn btn-primary btn-sm">PDF</a> <span class="bg-info text-light px-1 py-1 float-right rounded"> Downloads <span class="badge badge-light">190</span> </span> </div> </div> <div class="card paper-listing mb-3 mt-3"> <h5 class="card-header" style="font-size:.9rem"><span class="badge badge-info">475</span> The Effectiveness of Orthogonal Frequency Division Multiplexing as Modulation Technique</h5> <div class="card-body"> <p class="card-text"><strong>Authors:</strong> <a href="https://publications.waset.org/abstracts/search?q=Mohamed%20O.%20Babana">Mohamed O. Babana</a> </p> <p class="card-text"><strong>Abstract:</strong></p> In wireless channel multipath is the propagation phenomena where the transmitted signal arrive at the receiver side with many of paths, the signal at these paths arrive with different time delay the results is random signal fading due to intersymbols interference(ISI). This paper deals with identification of orthogonal frequency division multiplexing (OFDM) technology, and how it is used to overcome intersymbol interference due to multipath. Also investigates the effect of Additive White Gaussian Noise Channel (AWGN) on OFDM using multi-level modulation of Phase Shift Keying (PSK), computer simulation to calculate the bit error rate (BER) under AWGN channel is applied. A comparison study is carried out to obtain the Bit Error Rate performance for OFDM to identify the best multi-level modulation of PSK. <p class="card-text"><strong>Keywords:</strong> <a href="https://publications.waset.org/abstracts/search?q=intersymbol%20interference%28ISI%29" title="intersymbol interference(ISI)">intersymbol interference(ISI)</a>, <a href="https://publications.waset.org/abstracts/search?q=bit%20error%20rate%28BER%29" title=" bit error rate(BER)"> bit error rate(BER)</a>, <a href="https://publications.waset.org/abstracts/search?q=modulation" title=" modulation"> modulation</a>, <a href="https://publications.waset.org/abstracts/search?q=multiplexing" title=" multiplexing"> multiplexing</a>, <a href="https://publications.waset.org/abstracts/search?q=simulation" title=" simulation"> simulation</a> </p> <a href="https://publications.waset.org/abstracts/47691/the-effectiveness-of-orthogonal-frequency-division-multiplexing-as-modulation-technique" class="btn btn-primary btn-sm">Procedia</a> <a href="https://publications.waset.org/abstracts/47691.pdf" target="_blank" class="btn btn-primary btn-sm">PDF</a> <span class="bg-info text-light px-1 py-1 float-right rounded"> Downloads <span class="badge badge-light">422</span> </span> </div> </div> <div class="card paper-listing mb-3 mt-3"> <h5 class="card-header" style="font-size:.9rem"><span class="badge badge-info">474</span> An Improved Sub-Nyquist Sampling Jamming Method for Deceiving Inverse Synthetic Aperture Radar</h5> <div class="card-body"> <p class="card-text"><strong>Authors:</strong> <a href="https://publications.waset.org/abstracts/search?q=Yanli%20Qi">Yanli Qi</a>, <a href="https://publications.waset.org/abstracts/search?q=Ning%20Lv"> Ning Lv</a>, <a href="https://publications.waset.org/abstracts/search?q=Jing%20Li"> Jing Li</a> </p> <p class="card-text"><strong>Abstract:</strong></p> Sub-Nyquist sampling jamming method (SNSJ) is a well known deception jamming method for inverse synthetic aperture radar (ISAR). However, the anti-decoy of the SNSJ method performs easier since the amplitude of the false-target images are weaker than the real-target image; the false-target images always lag behind the real-target image, and all targets are located in the same cross-range. In order to overcome the drawbacks mentioned above, a simple modulation based on SNSJ (M-SNSJ) is presented in this paper. The method first uses amplitude modulation factor to make the amplitude of the false-target images consistent with the real-target image, then uses the down-range modulation factor and cross-range modulation factor to make the false-target images move freely in down-range and cross-range, respectively, thus the capacity of deception is improved. Finally, the simulation results on the six available combinations of three modulation factors are given to illustrate our conclusion. <p class="card-text"><strong>Keywords:</strong> <a href="https://publications.waset.org/abstracts/search?q=inverse%20synthetic%20aperture%20radar%20%28ISAR%29" title="inverse synthetic aperture radar (ISAR)">inverse synthetic aperture radar (ISAR)</a>, <a href="https://publications.waset.org/abstracts/search?q=deceptive%20jamming" title=" deceptive jamming"> deceptive jamming</a>, <a href="https://publications.waset.org/abstracts/search?q=Sub-Nyquist%20sampling%20jamming%20method%20%28SNSJ%29" title=" Sub-Nyquist sampling jamming method (SNSJ)"> Sub-Nyquist sampling jamming method (SNSJ)</a>, <a href="https://publications.waset.org/abstracts/search?q=modulation%20based%20on%20Sub-Nyquist%20sampling%20jamming%20method%20%28M-SNSJ%29" title=" modulation based on Sub-Nyquist sampling jamming method (M-SNSJ)"> modulation based on Sub-Nyquist sampling jamming method (M-SNSJ)</a> </p> <a href="https://publications.waset.org/abstracts/62644/an-improved-sub-nyquist-sampling-jamming-method-for-deceiving-inverse-synthetic-aperture-radar" class="btn btn-primary btn-sm">Procedia</a> <a href="https://publications.waset.org/abstracts/62644.pdf" target="_blank" class="btn btn-primary btn-sm">PDF</a> <span class="bg-info text-light px-1 py-1 float-right rounded"> Downloads <span class="badge badge-light">217</span> </span> </div> </div> <div class="card paper-listing mb-3 mt-3"> <h5 class="card-header" style="font-size:.9rem"><span class="badge badge-info">473</span> Construction of Graph Signal Modulations via Graph Fourier Transform and Its Applications</h5> <div class="card-body"> <p class="card-text"><strong>Authors:</strong> <a href="https://publications.waset.org/abstracts/search?q=Xianwei%20Zheng">Xianwei Zheng</a>, <a href="https://publications.waset.org/abstracts/search?q=Yuan%20Yan%20Tang"> Yuan Yan Tang</a> </p> <p class="card-text"><strong>Abstract:</strong></p> Classical window Fourier transform has been widely used in signal processing, image processing, machine learning and pattern recognition. The related Gabor transform is powerful enough to capture the texture information of any given dataset. Recently, in the emerging field of graph signal processing, researchers devoting themselves to develop a graph signal processing theory to handle the so-called graph signals. Among the new developing theory, windowed graph Fourier transform has been constructed to establish a time-frequency analysis framework of graph signals. The windowed graph Fourier transform is defined by using the translation and modulation operators of graph signals, following the similar calculations in classical windowed Fourier transform. Specifically, the translation and modulation operators of graph signals are defined by using the Laplacian eigenvectors as follows. For a given graph signal, its translation is defined by a similar manner as its definition in classical signal processing. Specifically, the translation operator can be defined by using the Fourier atoms; the graph signal translation is defined similarly by using the Laplacian eigenvectors. The modulation of the graph can also be established by using the Laplacian eigenvectors. The windowed graph Fourier transform based on these two operators has been applied to obtain time-frequency representations of graph signals. Fundamentally, the modulation operator is defined similarly to the classical modulation by multiplying a graph signal with the entries in each Fourier atom. However, a single Laplacian eigenvector entry cannot play a similar role as the Fourier atom. This definition ignored the relationship between the translation and modulation operators. In this paper, a new definition of the modulation operator is proposed and thus another time-frequency framework for graph signal is constructed. Specifically, the relationship between the translation and modulation operations can be established by the Fourier transform. Specifically, for any signal, the Fourier transform of its translation is the modulation of its Fourier transform. Thus, the modulation of any signal can be defined as the inverse Fourier transform of the translation of its Fourier transform. Therefore, similarly, the graph modulation of any graph signal can be defined as the inverse graph Fourier transform of the translation of its graph Fourier. The novel definition of the graph modulation operator established a relationship of the translation and modulation operations. The new modulation operation and the original translation operation are applied to construct a new framework of graph signal time-frequency analysis. Furthermore, a windowed graph Fourier frame theory is developed. Necessary and sufficient conditions for constructing windowed graph Fourier frames, tight frames and dual frames are presented in this paper. The novel graph signal time-frequency analysis framework is applied to signals defined on well-known graphs, e.g. Minnesota road graph and random graphs. Experimental results show that the novel framework captures new features of graph signals. <p class="card-text"><strong>Keywords:</strong> <a href="https://publications.waset.org/abstracts/search?q=graph%20signals" title="graph signals">graph signals</a>, <a href="https://publications.waset.org/abstracts/search?q=windowed%20graph%20Fourier%20transform" title=" windowed graph Fourier transform"> windowed graph Fourier transform</a>, <a href="https://publications.waset.org/abstracts/search?q=windowed%20graph%20Fourier%20frames" title=" windowed graph Fourier frames"> windowed graph Fourier frames</a>, <a href="https://publications.waset.org/abstracts/search?q=vertex%20frequency%20analysis" title=" vertex frequency analysis"> vertex frequency analysis</a> </p> <a href="https://publications.waset.org/abstracts/63133/construction-of-graph-signal-modulations-via-graph-fourier-transform-and-its-applications" class="btn btn-primary btn-sm">Procedia</a> <a href="https://publications.waset.org/abstracts/63133.pdf" target="_blank" class="btn btn-primary btn-sm">PDF</a> <span class="bg-info text-light px-1 py-1 float-right rounded"> Downloads <span class="badge badge-light">341</span> </span> </div> </div> <div class="card paper-listing mb-3 mt-3"> <h5 class="card-header" style="font-size:.9rem"><span class="badge badge-info">472</span> Comparative Analysis of SVPWM and the Standard PWM Technique for Three Level Diode Clamped Inverter fed Induction Motor</h5> <div class="card-body"> <p class="card-text"><strong>Authors:</strong> <a href="https://publications.waset.org/abstracts/search?q=L.%20Lakhdari">L. Lakhdari</a>, <a href="https://publications.waset.org/abstracts/search?q=B.%20Bouchiba"> B. Bouchiba</a>, <a href="https://publications.waset.org/abstracts/search?q=M.%20Bechar"> M. Bechar</a> </p> <p class="card-text"><strong>Abstract:</strong></p> The multi-level inverters present an important novelty in the field of energy control with high voltage and power. The major advantage of all multi-level inverters is the improvement and spectral quality of its generated output signals. In recent years, various pulse width modulation techniques have been developed. From these technics we have: Sinusoidal Pulse Width Modulation (SPWM) and Space Vector Pulse Width Modulation (SVPWM). This work presents a detailed analysis of the comparative advantage of space vector pulse width modulation (SVPWM) and the standard SPWM technique for Three Level Diode Clamped Inverter fed Induction Motor. The comparison is based on the evaluation of harmonic distortion THD. <p class="card-text"><strong>Keywords:</strong> <a href="https://publications.waset.org/abstracts/search?q=induction%20motor" title="induction motor">induction motor</a>, <a href="https://publications.waset.org/abstracts/search?q=multilevel%20inverters" title=" multilevel inverters"> multilevel inverters</a>, <a href="https://publications.waset.org/abstracts/search?q=SVPWM" title=" SVPWM"> SVPWM</a>, <a href="https://publications.waset.org/abstracts/search?q=SPWM" title=" SPWM"> SPWM</a>, <a href="https://publications.waset.org/abstracts/search?q=THD" title=" THD"> THD</a> </p> <a href="https://publications.waset.org/abstracts/71132/comparative-analysis-of-svpwm-and-the-standard-pwm-technique-for-three-level-diode-clamped-inverter-fed-induction-motor" class="btn btn-primary btn-sm">Procedia</a> <a href="https://publications.waset.org/abstracts/71132.pdf" target="_blank" class="btn btn-primary btn-sm">PDF</a> <span class="bg-info text-light px-1 py-1 float-right rounded"> Downloads <span class="badge badge-light">338</span> </span> </div> </div> <div class="card paper-listing mb-3 mt-3"> <h5 class="card-header" style="font-size:.9rem"><span class="badge badge-info">471</span> Channel Estimation/Equalization with Adaptive Modulation and Coding over Multipath Faded Channels for WiMAX</h5> <div class="card-body"> <p class="card-text"><strong>Authors:</strong> <a href="https://publications.waset.org/abstracts/search?q=B.%20Siva%20Kumar%20Reddy">B. Siva Kumar Reddy</a>, <a href="https://publications.waset.org/abstracts/search?q=B.%20Lakshmi"> B. Lakshmi</a> </p> <p class="card-text"><strong>Abstract:</strong></p> WiMAX has adopted an Adaptive Modulation and Coding (AMC) in OFDM to endure higher data rates and error free transmission. AMC schemes employ the Channel State Information (CSI) to efficiently utilize the channel and maximize the throughput and for better spectral efficiency. This CSI has given to the transmitter by the channel estimators. In this paper, LSE (Least Square Error) and MMSE (Minimum Mean square Error) estimators are suggested and BER (Bit Error Rate) performance has been analyzed. Channel equalization is also integrated with with AMC-OFDM system and presented with Constant Modulus Algorithm (CMA) and Least Mean Square (LMS) algorithms with convergence rates analysis. Simulation results proved that increment in modulation scheme size causes to improvement in throughput along with BER value. There is a trade-off among modulation size, throughput, BER value and spectral efficiency. Results also reported the requirement of channel estimation and equalization in high data rate systems. <p class="card-text"><strong>Keywords:</strong> <a href="https://publications.waset.org/abstracts/search?q=AMC" title="AMC">AMC</a>, <a href="https://publications.waset.org/abstracts/search?q=CSI" title=" CSI"> CSI</a>, <a href="https://publications.waset.org/abstracts/search?q=CMA" title=" CMA"> CMA</a>, <a href="https://publications.waset.org/abstracts/search?q=OFDM" title=" OFDM"> OFDM</a>, <a href="https://publications.waset.org/abstracts/search?q=OFDMA" title=" OFDMA"> OFDMA</a>, <a href="https://publications.waset.org/abstracts/search?q=WiMAX" title=" WiMAX"> WiMAX</a> </p> <a href="https://publications.waset.org/abstracts/14902/channel-estimationequalization-with-adaptive-modulation-and-coding-over-multipath-faded-channels-for-wimax" class="btn btn-primary btn-sm">Procedia</a> <a href="https://publications.waset.org/abstracts/14902.pdf" target="_blank" class="btn btn-primary btn-sm">PDF</a> <span class="bg-info text-light px-1 py-1 float-right rounded"> Downloads <span class="badge badge-light">393</span> </span> </div> </div> <div class="card paper-listing mb-3 mt-3"> <h5 class="card-header" style="font-size:.9rem"><span class="badge badge-info">470</span> Channel Length Modulation Effect on Monolayer Graphene Nanoribbon Field Effect Transistor</h5> <div class="card-body"> <p class="card-text"><strong>Authors:</strong> <a href="https://publications.waset.org/abstracts/search?q=Mehdi%20Saeidmanesh">Mehdi Saeidmanesh</a>, <a href="https://publications.waset.org/abstracts/search?q=Razali%20Ismail"> Razali Ismail</a> </p> <p class="card-text"><strong>Abstract:</strong></p> Recently, Graphene Nanoribbon Field Effect Transistors (GNR FETs) attract a great deal of attention due to their better performance in comparison with conventional devices. In this paper, channel length Modulation (CLM) effect on the electrical characteristics of GNR FETs is analytically studied and modeled. To this end, the special distribution of the electric potential along the channel and current-voltage characteristic of the device is modeled. The obtained results of analytical model are compared to the experimental data of published works. As a result, it is observable that considering the effect of CLM, the current-voltage response of GNR FET is more realistic. <p class="card-text"><strong>Keywords:</strong> <a href="https://publications.waset.org/abstracts/search?q=graphene%20nanoribbon" title="graphene nanoribbon">graphene nanoribbon</a>, <a href="https://publications.waset.org/abstracts/search?q=field%20effect%20transistors" title=" field effect transistors"> field effect transistors</a>, <a href="https://publications.waset.org/abstracts/search?q=short%20channel%20effects" title=" short channel effects"> short channel effects</a>, <a href="https://publications.waset.org/abstracts/search?q=channel%20length%20modulation" title=" channel length modulation"> channel length modulation</a> </p> <a href="https://publications.waset.org/abstracts/42745/channel-length-modulation-effect-on-monolayer-graphene-nanoribbon-field-effect-transistor" class="btn btn-primary btn-sm">Procedia</a> <a href="https://publications.waset.org/abstracts/42745.pdf" target="_blank" class="btn btn-primary btn-sm">PDF</a> <span class="bg-info text-light px-1 py-1 float-right rounded"> Downloads <span class="badge badge-light">402</span> </span> </div> </div> <div class="card paper-listing mb-3 mt-3"> <h5 class="card-header" style="font-size:.9rem"><span class="badge badge-info">469</span> Performance Analysis of VoIP Coders for Different Modulations Under Pervasive Environment</h5> <div class="card-body"> <p class="card-text"><strong>Authors:</strong> <a href="https://publications.waset.org/abstracts/search?q=Jasbinder%20Singh">Jasbinder Singh</a>, <a href="https://publications.waset.org/abstracts/search?q=Harjit%20Pal%20Singh"> Harjit Pal Singh</a>, <a href="https://publications.waset.org/abstracts/search?q=S.%20A.%20Khan"> S. A. Khan</a> </p> <p class="card-text"><strong>Abstract:</strong></p> The work, in this paper, presents the comparison of encoded speech signals by different VoIP narrow-band and wide-band codecs for different modulation schemes. The simulation results indicate that codec has an impact on the speech quality and also effected by modulation schemes. <p class="card-text"><strong>Keywords:</strong> <a href="https://publications.waset.org/abstracts/search?q=VoIP" title="VoIP">VoIP</a>, <a href="https://publications.waset.org/abstracts/search?q=coders" title=" coders"> coders</a>, <a href="https://publications.waset.org/abstracts/search?q=modulations" title=" modulations"> modulations</a>, <a href="https://publications.waset.org/abstracts/search?q=BER" title=" BER"> BER</a>, <a href="https://publications.waset.org/abstracts/search?q=MOS" title=" MOS"> MOS</a> </p> <a href="https://publications.waset.org/abstracts/8221/performance-analysis-of-voip-coders-for-different-modulations-under-pervasive-environment" class="btn btn-primary btn-sm">Procedia</a> <a href="https://publications.waset.org/abstracts/8221.pdf" target="_blank" class="btn btn-primary btn-sm">PDF</a> <span class="bg-info text-light px-1 py-1 float-right rounded"> Downloads <span class="badge badge-light">515</span> </span> </div> </div> <div class="card paper-listing mb-3 mt-3"> <h5 class="card-header" style="font-size:.9rem"><span class="badge badge-info">468</span> Enhancement of coupler-based delay line filters modulation techniques using optical wireless channel and amplifiers at 100 Gbit/s</h5> <div class="card-body"> <p class="card-text"><strong>Authors:</strong> <a href="https://publications.waset.org/abstracts/search?q=Divya%20Sisodiya">Divya Sisodiya</a>, <a href="https://publications.waset.org/abstracts/search?q=Deepika%20Sipal"> Deepika Sipal</a> </p> <p class="card-text"><strong>Abstract:</strong></p> Optical wireless communication (OWC) is a relatively new technology in optical communication systems that allows for high-speed wireless optical communication. This research focuses on developing a cost-effective OWC system using a hybrid configuration of optical amplifiers. In addition to using EDFA amplifiers, a comparison study was conducted to determine which modulation technique is more effective for communication. This research examines the performance of an OWC system based on ASK and PSK modulation techniques by varying OWC parameters under various atmospheric conditions such as rain, mist, haze, and snow. Finally, the simulation results are discussed and analyzed. <p class="card-text"><strong>Keywords:</strong> <a href="https://publications.waset.org/abstracts/search?q=OWC" title="OWC">OWC</a>, <a href="https://publications.waset.org/abstracts/search?q=bit%20error%20rate" title=" bit error rate"> bit error rate</a>, <a href="https://publications.waset.org/abstracts/search?q=amplitude%20shift%20keying" title=" amplitude shift keying"> amplitude shift keying</a>, <a href="https://publications.waset.org/abstracts/search?q=phase%20shift%20keying" title=" phase shift keying"> phase shift keying</a>, <a href="https://publications.waset.org/abstracts/search?q=attenuation" title=" attenuation"> attenuation</a>, <a href="https://publications.waset.org/abstracts/search?q=amplifiers" title=" amplifiers"> amplifiers</a> </p> <a href="https://publications.waset.org/abstracts/150218/enhancement-of-coupler-based-delay-line-filters-modulation-techniques-using-optical-wireless-channel-and-amplifiers-at-100-gbits" class="btn btn-primary btn-sm">Procedia</a> <a href="https://publications.waset.org/abstracts/150218.pdf" target="_blank" class="btn btn-primary btn-sm">PDF</a> <span class="bg-info text-light px-1 py-1 float-right rounded"> Downloads <span class="badge badge-light">132</span> </span> </div> </div> <div class="card paper-listing mb-3 mt-3"> <h5 class="card-header" style="font-size:.9rem"><span class="badge badge-info">467</span> Improved Small-Signal Characteristics of Infrared 850 nm Top-Emitting Vertical-Cavity Lasers</h5> <div class="card-body"> <p class="card-text"><strong>Authors:</strong> <a href="https://publications.waset.org/abstracts/search?q=Ahmad%20Al-Omari">Ahmad Al-Omari</a>, <a href="https://publications.waset.org/abstracts/search?q=Osama%20Khreis"> Osama Khreis</a>, <a href="https://publications.waset.org/abstracts/search?q=Ahmad%20M.%20K.%20Dagamseh"> Ahmad M. K. Dagamseh</a>, <a href="https://publications.waset.org/abstracts/search?q=Abdullah%20Ababneh"> Abdullah Ababneh</a>, <a href="https://publications.waset.org/abstracts/search?q=Kevin%20Lear"> Kevin Lear</a> </p> <p class="card-text"><strong>Abstract:</strong></p> High-speed infrared vertical-cavity surface-emitting laser diodes (VCSELs) with Cu-plated heat sinks were fabricated and tested. VCSELs with 10 mm aperture diameter and 4 mm of electroplated copper demonstrated a -3dB modulation bandwidth (<em>f</em><sub>-3dB</sub>) of 14 GHz and a resonance frequency (<em>f</em><sub>R</sub>) of 9.5 GHz at a bias current density (<em>J<sub>bias</sub></em>) of only 4.3 kA/cm<sup>2</sup>, which corresponds to an improved <em>f</em><sub>-3dB</sub><sup>2</sup>/<em>J<sub>bias</sub></em> ratio of 44 GHz<sup>2</sup>/kA/cm<sup>2</sup>. At higher and lower bias current densities, the <em>f</em><sub>-3dB</sub><sup>2</sup>/<em> J<sub>bias</sub></em> ratio decreased to about 30 GHz<sup>2</sup>/kA/cm<sup>2</sup> and 18 GHz<sup>2</sup>/kA/cm<sup>2</sup>, respectively. Examination of the analogue modulation response demonstrated that the presented VCSELs displayed a steady <em>f</em><sub>-3dB</sub>/<em> f</em><sub>R</sub> ratio of 1.41&plusmn;10% over the whole range of the bias current (1.3<em>I</em><sub>th</sub> to 6.2<em>I</em><sub>th</sub>). The devices also demonstrated a maximum modulation bandwidth (<em>f</em><sub>-3dB max</sub>) of more than 16 GHz at a bias current less than the industrial bias current standard for reliability by 25%. <p class="card-text"><strong>Keywords:</strong> <a href="https://publications.waset.org/abstracts/search?q=current%20density" title="current density">current density</a>, <a href="https://publications.waset.org/abstracts/search?q=high-speed%20VCSELs" title=" high-speed VCSELs"> high-speed VCSELs</a>, <a href="https://publications.waset.org/abstracts/search?q=modulation%20bandwidth" title=" modulation bandwidth"> modulation bandwidth</a>, <a href="https://publications.waset.org/abstracts/search?q=small-signal%20characteristics" title=" small-signal characteristics"> small-signal characteristics</a>, <a href="https://publications.waset.org/abstracts/search?q=thermal%20impedance" title=" thermal impedance"> thermal impedance</a>, <a href="https://publications.waset.org/abstracts/search?q=vertical-cavity%20surface-emitting%20lasers" title=" vertical-cavity surface-emitting lasers"> vertical-cavity surface-emitting lasers</a> </p> <a href="https://publications.waset.org/abstracts/78212/improved-small-signal-characteristics-of-infrared-850-nm-top-emitting-vertical-cavity-lasers" class="btn btn-primary btn-sm">Procedia</a> <a href="https://publications.waset.org/abstracts/78212.pdf" target="_blank" class="btn btn-primary btn-sm">PDF</a> <span class="bg-info text-light px-1 py-1 float-right rounded"> Downloads <span class="badge badge-light">569</span> </span> </div> </div> <div class="card paper-listing mb-3 mt-3"> <h5 class="card-header" style="font-size:.9rem"><span class="badge badge-info">466</span> Cooperative CDD Scheme Based On Hierarchical Modulation in OFDM System</h5> <div class="card-body"> <p class="card-text"><strong>Authors:</strong> <a href="https://publications.waset.org/abstracts/search?q=Seung-Jun%20Yu">Seung-Jun Yu</a>, <a href="https://publications.waset.org/abstracts/search?q=Yeong-Seop%20Ahn"> Yeong-Seop Ahn</a>, <a href="https://publications.waset.org/abstracts/search?q=Young-Min%20Ko"> Young-Min Ko</a>, <a href="https://publications.waset.org/abstracts/search?q=Hyoung-Kyu%20Song">Hyoung-Kyu Song</a> </p> <p class="card-text"><strong>Abstract:</strong></p> In order to achieve high data rate and increase the spectral efficiency, multiple input multiple output (MIMO) system has been proposed. However, multiple antennas are limited by size and cost. Therefore, recently developed cooperative diversity scheme, which profits the transmit diversity only with the existing hardware by constituting a virtual antenna array, can be a solution. However, most of the introduced cooperative techniques have a common fault of decreased transmission rate because the destination should receive the decodable compositions of symbols from the source and the relay. In this paper, we propose a cooperative cyclic delay diversity (CDD) scheme that uses hierarchical modulation. This scheme is free from the rate loss and allows seamless cooperative communication. <p class="card-text"><strong>Keywords:</strong> <a href="https://publications.waset.org/abstracts/search?q=MIMO" title="MIMO">MIMO</a>, <a href="https://publications.waset.org/abstracts/search?q=cooperative%20communication" title=" cooperative communication"> cooperative communication</a>, <a href="https://publications.waset.org/abstracts/search?q=CDD" title=" CDD"> CDD</a>, <a href="https://publications.waset.org/abstracts/search?q=hierarchical%20modulation" title=" hierarchical modulation"> hierarchical modulation</a> </p> <a href="https://publications.waset.org/abstracts/32286/cooperative-cdd-scheme-based-on-hierarchical-modulation-in-ofdm-system" class="btn btn-primary btn-sm">Procedia</a> <a href="https://publications.waset.org/abstracts/32286.pdf" target="_blank" class="btn btn-primary btn-sm">PDF</a> <span class="bg-info text-light px-1 py-1 float-right rounded"> Downloads <span class="badge badge-light">549</span> </span> </div> </div> <div class="card paper-listing mb-3 mt-3"> <h5 class="card-header" style="font-size:.9rem"><span class="badge badge-info">465</span> Role of Human Milk Oligosaccharides (HMOs) in Epigenetic Modulation of Bacterial Pathogen in Infant and Toddler</h5> <div class="card-body"> <p class="card-text"><strong>Authors:</strong> <a href="https://publications.waset.org/abstracts/search?q=Aftab%20Yusuf%20Raj">Aftab Yusuf Raj</a> </p> <p class="card-text"><strong>Abstract:</strong></p> Human milk oligosaccharides (HMOs) are complex carbohydrates. They are 3rd most abundant solid component found in breast milk, after lactose and lipids. HMO has profound beneficial health benefit effects on infants and toddlers. They have diverse roles, in immuno-modulation, development of neonatal gut, influencing the commensal microbiota of developing gut, and anti-inflammatory functions. HMOs, gut and commensal microbiota of the gut work synergistically to bring positive impact on infant and toddler health. HMO influences the gut-brain axis, maintains good mental health and cognitive function and inhibits neuronal inflammation. HMOs are now applied in infant nutrition, and supplementation of HMOs in infant formula is a promising innovation for infant nutrition. <p class="card-text"><strong>Keywords:</strong> <a href="https://publications.waset.org/abstracts/search?q=HMO%E2%80%99s" title="HMO鈥檚">HMO鈥檚</a>, <a href="https://publications.waset.org/abstracts/search?q=gut" title=" gut"> gut</a>, <a href="https://publications.waset.org/abstracts/search?q=epigenetic%20modulation" title=" epigenetic modulation"> epigenetic modulation</a>, <a href="https://publications.waset.org/abstracts/search?q=bacteria" title=" bacteria"> bacteria</a> </p> <a href="https://publications.waset.org/abstracts/191265/role-of-human-milk-oligosaccharides-hmos-in-epigenetic-modulation-of-bacterial-pathogen-in-infant-and-toddler" class="btn btn-primary btn-sm">Procedia</a> <a href="https://publications.waset.org/abstracts/191265.pdf" target="_blank" class="btn btn-primary btn-sm">PDF</a> <span class="bg-info text-light px-1 py-1 float-right rounded"> Downloads <span class="badge badge-light">29</span> </span> </div> </div> <div class="card paper-listing mb-3 mt-3"> <h5 class="card-header" style="font-size:.9rem"><span class="badge badge-info">464</span> Plastic Pipe Defect Detection Using Nonlinear Acoustic Modulation </h5> <div class="card-body"> <p class="card-text"><strong>Authors:</strong> <a href="https://publications.waset.org/abstracts/search?q=Gigih%20Priyandoko">Gigih Priyandoko</a>, <a href="https://publications.waset.org/abstracts/search?q=Mohd%20Fairusham%20Ghazali"> Mohd Fairusham Ghazali</a>, <a href="https://publications.waset.org/abstracts/search?q=Tan%20Siew%20Fun"> Tan Siew Fun </a> </p> <p class="card-text"><strong>Abstract:</strong></p> This paper discusses about the defect detection of plastic pipe by using nonlinear acoustic wave modulation method. It is a sensitive method for damage detection and it is based on the propagation of high frequency acoustic waves in plastic pipe with low frequency excitation. The plastic pipe is excited simultaneously with a slow amplitude modulated vibration pumping wave and a constant amplitude probing wave. The frequency of both the excitation signals coincides with the resonances of the plastic pipe. A PVP pipe is used as the specimen as it is commonly used for the conveyance of liquid in many fields. The results obtained are being observed and the difference between uncracked specimen and cracked specimen can be distinguished clearly. <p class="card-text"><strong>Keywords:</strong> <a href="https://publications.waset.org/abstracts/search?q=plastic%20pipe" title="plastic pipe">plastic pipe</a>, <a href="https://publications.waset.org/abstracts/search?q=defect%20detection" title=" defect detection"> defect detection</a>, <a href="https://publications.waset.org/abstracts/search?q=nonlinear%20acoustic%20modulation" title=" nonlinear acoustic modulation"> nonlinear acoustic modulation</a>, <a href="https://publications.waset.org/abstracts/search?q=excitation" title=" excitation"> excitation</a> </p> <a href="https://publications.waset.org/abstracts/16837/plastic-pipe-defect-detection-using-nonlinear-acoustic-modulation" class="btn btn-primary btn-sm">Procedia</a> <a href="https://publications.waset.org/abstracts/16837.pdf" target="_blank" class="btn btn-primary btn-sm">PDF</a> <span class="bg-info text-light px-1 py-1 float-right rounded"> Downloads <span class="badge badge-light">451</span> </span> </div> </div> <div class="card paper-listing mb-3 mt-3"> <h5 class="card-header" style="font-size:.9rem"><span class="badge badge-info">463</span> Time and Wavelength Division Multiplexing Passive Optical Network Comparative Analysis: Modulation Formats and Channel Spacings</h5> <div class="card-body"> <p class="card-text"><strong>Authors:</strong> <a href="https://publications.waset.org/abstracts/search?q=A.%20Fayad">A. Fayad</a>, <a href="https://publications.waset.org/abstracts/search?q=Q.%20Alqhazaly"> Q. Alqhazaly</a>, <a href="https://publications.waset.org/abstracts/search?q=T.%20Cinkler"> T. Cinkler</a> </p> <p class="card-text"><strong>Abstract:</strong></p> In light of the substantial increase in end-user requirements and the incessant need of network operators to upgrade the capabilities of access networks, in this paper, the performance of the different modulation formats on eight-channels Time and Wavelength Division Multiplexing Passive Optical Network (TWDM-PON) transmission system has been examined and compared. Limitations and features of modulation formats have been determined to outline the most suitable design to enhance the data rate and transmission reach to obtain the best performance of the network. The considered modulation formats are On-Off Keying Non-Return-to-Zero (NRZ-OOK), Carrier Suppressed Return to Zero (CSRZ), Duo Binary (DB), Modified Duo Binary (MODB), Quadrature Phase Shift Keying (QPSK), and Differential Quadrature Phase Shift Keying (DQPSK). The performance has been analyzed by varying transmission distances and bit rates under different channel spacing. Furthermore, the system is evaluated in terms of minimum Bit Error Rate (BER) and Quality factor (Qf) without applying any dispersion compensation technique, or any optical amplifier. Optisystem software was used for simulation purposes. <p class="card-text"><strong>Keywords:</strong> <a href="https://publications.waset.org/abstracts/search?q=BER" title="BER">BER</a>, <a href="https://publications.waset.org/abstracts/search?q=DuoBinary" title=" DuoBinary"> DuoBinary</a>, <a href="https://publications.waset.org/abstracts/search?q=NRZ-OOK" title=" NRZ-OOK"> NRZ-OOK</a>, <a href="https://publications.waset.org/abstracts/search?q=TWDM-PON" title=" TWDM-PON"> TWDM-PON</a> </p> <a href="https://publications.waset.org/abstracts/136771/time-and-wavelength-division-multiplexing-passive-optical-network-comparative-analysis-modulation-formats-and-channel-spacings" class="btn btn-primary btn-sm">Procedia</a> <a href="https://publications.waset.org/abstracts/136771.pdf" target="_blank" class="btn btn-primary btn-sm">PDF</a> <span class="bg-info text-light px-1 py-1 float-right rounded"> Downloads <span class="badge badge-light">149</span> </span> </div> </div> <div class="card paper-listing mb-3 mt-3"> <h5 class="card-header" style="font-size:.9rem"><span class="badge badge-info">462</span> Stabilizing Effect of Magnetic Field in a Thermally Modulated Porous Layer</h5> <div class="card-body"> <p class="card-text"><strong>Authors:</strong> <a href="https://publications.waset.org/abstracts/search?q=M.%20Meenasaranya">M. Meenasaranya</a>, <a href="https://publications.waset.org/abstracts/search?q=S.%20Saravanan"> S. Saravanan</a> </p> <p class="card-text"><strong>Abstract:</strong></p> Nonlinear stability analysis is carried out to determine the effect of surface temperature modulation in an infinite horizontal porous layer heated from below. The layer is saturated by an electrically conducting, viscous, incompressible and Newtonian fluid. The Brinkman model is used for momentum equation, and the Boussinesq approximation is invoked. The system is assumed to be bounded by rigid boundaries. The energy theory is implemented to find the global exponential stability region of the considered system. The results are analysed for arbitrary values of modulation frequency and amplitude. The existence of subcritical instability region is confirmed by comparing the obtained result with the known linear result. The vertical magnetic field is found to stabilize the system. <p class="card-text"><strong>Keywords:</strong> <a href="https://publications.waset.org/abstracts/search?q=Brinkman%20model" title="Brinkman model">Brinkman model</a>, <a href="https://publications.waset.org/abstracts/search?q=energy%20method" title=" energy method"> energy method</a>, <a href="https://publications.waset.org/abstracts/search?q=magnetic%20field" title=" magnetic field"> magnetic field</a>, <a href="https://publications.waset.org/abstracts/search?q=surface%20temperature%20modulation" title=" surface temperature modulation"> surface temperature modulation</a> </p> <a href="https://publications.waset.org/abstracts/66404/stabilizing-effect-of-magnetic-field-in-a-thermally-modulated-porous-layer" class="btn btn-primary btn-sm">Procedia</a> <a href="https://publications.waset.org/abstracts/66404.pdf" target="_blank" class="btn btn-primary btn-sm">PDF</a> <span class="bg-info text-light px-1 py-1 float-right rounded"> Downloads <span class="badge badge-light">395</span> </span> </div> </div> <ul class="pagination"> <li class="page-item disabled"><span class="page-link">&lsaquo;</span></li> <li class="page-item active"><span class="page-link">1</span></li> <li class="page-item"><a class="page-link" href="https://publications.waset.org/abstracts/search?q=modulation&amp;page=2">2</a></li> <li class="page-item"><a class="page-link" href="https://publications.waset.org/abstracts/search?q=modulation&amp;page=3">3</a></li> <li class="page-item"><a class="page-link" href="https://publications.waset.org/abstracts/search?q=modulation&amp;page=4">4</a></li> <li class="page-item"><a class="page-link" href="https://publications.waset.org/abstracts/search?q=modulation&amp;page=5">5</a></li> <li class="page-item"><a class="page-link" href="https://publications.waset.org/abstracts/search?q=modulation&amp;page=6">6</a></li> <li class="page-item"><a class="page-link" href="https://publications.waset.org/abstracts/search?q=modulation&amp;page=7">7</a></li> <li class="page-item"><a class="page-link" href="https://publications.waset.org/abstracts/search?q=modulation&amp;page=8">8</a></li> <li class="page-item"><a class="page-link" href="https://publications.waset.org/abstracts/search?q=modulation&amp;page=9">9</a></li> <li class="page-item"><a class="page-link" href="https://publications.waset.org/abstracts/search?q=modulation&amp;page=10">10</a></li> <li class="page-item disabled"><span class="page-link">...</span></li> <li class="page-item"><a class="page-link" href="https://publications.waset.org/abstracts/search?q=modulation&amp;page=16">16</a></li> <li class="page-item"><a class="page-link" href="https://publications.waset.org/abstracts/search?q=modulation&amp;page=17">17</a></li> <li class="page-item"><a class="page-link" href="https://publications.waset.org/abstracts/search?q=modulation&amp;page=2" rel="next">&rsaquo;</a></li> </ul> </div> </main> <footer> <div id="infolinks" class="pt-3 pb-2"> <div class="container"> <div style="background-color:#f5f5f5;" class="p-3"> <div class="row"> <div class="col-md-2"> <ul class="list-unstyled"> About <li><a href="https://waset.org/page/support">About Us</a></li> <li><a href="https://waset.org/page/support#legal-information">Legal</a></li> <li><a target="_blank" rel="nofollow" href="https://publications.waset.org/static/files/WASET-16th-foundational-anniversary.pdf">WASET celebrates its 16th foundational anniversary</a></li> </ul> </div> <div class="col-md-2"> <ul class="list-unstyled"> Account <li><a href="https://waset.org/profile">My Account</a></li> </ul> </div> <div class="col-md-2"> <ul class="list-unstyled"> Explore <li><a href="https://waset.org/disciplines">Disciplines</a></li> <li><a href="https://waset.org/conferences">Conferences</a></li> <li><a href="https://waset.org/conference-programs">Conference Program</a></li> <li><a href="https://waset.org/committees">Committees</a></li> <li><a href="https://publications.waset.org">Publications</a></li> </ul> </div> <div class="col-md-2"> <ul class="list-unstyled"> Research <li><a href="https://publications.waset.org/abstracts">Abstracts</a></li> <li><a href="https://publications.waset.org">Periodicals</a></li> <li><a href="https://publications.waset.org/archive">Archive</a></li> </ul> </div> <div class="col-md-2"> <ul class="list-unstyled"> Open Science <li><a target="_blank" rel="nofollow" href="https://publications.waset.org/static/files/Open-Science-Philosophy.pdf">Open Science Philosophy</a></li> <li><a target="_blank" rel="nofollow" href="https://publications.waset.org/static/files/Open-Science-Award.pdf">Open Science Award</a></li> <li><a target="_blank" rel="nofollow" href="https://publications.waset.org/static/files/Open-Society-Open-Science-and-Open-Innovation.pdf">Open Innovation</a></li> <li><a target="_blank" rel="nofollow" href="https://publications.waset.org/static/files/Postdoctoral-Fellowship-Award.pdf">Postdoctoral Fellowship Award</a></li> <li><a target="_blank" rel="nofollow" href="https://publications.waset.org/static/files/Scholarly-Research-Review.pdf">Scholarly Research Review</a></li> </ul> </div> <div class="col-md-2"> <ul class="list-unstyled"> Support <li><a href="https://waset.org/page/support">Support</a></li> <li><a href="https://waset.org/profile/messages/create">Contact Us</a></li> <li><a href="https://waset.org/profile/messages/create">Report Abuse</a></li> </ul> </div> </div> </div> </div> </div> <div class="container text-center"> <hr style="margin-top:0;margin-bottom:.3rem;"> <a href="https://creativecommons.org/licenses/by/4.0/" target="_blank" class="text-muted small">Creative Commons Attribution 4.0 International License</a> <div id="copy" class="mt-2">&copy; 2024 World Academy of Science, Engineering and Technology</div> </div> </footer> <a href="javascript:" id="return-to-top"><i class="fas fa-arrow-up"></i></a> <div class="modal" id="modal-template"> <div class="modal-dialog"> <div class="modal-content"> <div class="row m-0 mt-1"> <div class="col-md-12"> <button type="button" class="close" data-dismiss="modal" aria-label="Close"><span aria-hidden="true">&times;</span></button> </div> </div> <div class="modal-body"></div> </div> </div> </div> <script src="https://cdn.waset.org/static/plugins/jquery-3.3.1.min.js"></script> <script src="https://cdn.waset.org/static/plugins/bootstrap-4.2.1/js/bootstrap.bundle.min.js"></script> <script src="https://cdn.waset.org/static/js/site.js?v=150220211556"></script> <script> jQuery(document).ready(function() { /*jQuery.get("https://publications.waset.org/xhr/user-menu", function (response) { jQuery('#mainNavMenu').append(response); });*/ jQuery.get({ url: "https://publications.waset.org/xhr/user-menu", cache: false }).then(function(response){ jQuery('#mainNavMenu').append(response); }); }); </script> </body> </html>

Pages: 1 2 3 4 5 6 7 8 9 10