{"title":"Impedance Matching of Axial Mode Helical Antennas","authors":"Hossein Mardani, Neil Buchanan, Robert Cahill, Vincent Fusco","volume":173,"journal":"International Journal of Electronics and Communication Engineering","pagesStart":205,"pagesEnd":209,"ISSN":"1307-6892","URL":"https:\/\/publications.waset.org\/pdf\/10012027","abstract":"<p>In this paper, we study the input impedance characteristics of axial mode helical antennas to find an effective way for matching it to 50 \u2126. The study is done on the important matching parameters such as like wire diameter and helix to the ground plane gap. It is intended that these parameters control the matching without detrimentally affecting the radiation pattern. Using transmission line theory, a simple broadband technique is proposed, which is applicable for perfect matching of antennas with similar design parameters. We provide design curves to help to choose the proper dimensions of the matching section based on the antenna&rsquo;s unmatched input impedance. Finally, using the proposed technique, a 4-turn axial mode helix is designed at 2.5 GHz center frequency and the measurement results of the manufactured antenna will be included. This parametric study gives a good insight into the input impedance characteristics of axial mode helical antennas and the proposed impedance matching approach provides a simple, useful method for matching these types of antennas.<\/p>\r\n","references":"[1]\tJ. D. Kraus, \"The Helical Antenna,\" in Proceedings of the IRE, vol. 37, no. 3, pp. 263-272, March 1949, doi: 10.1109\/JRPROC.1949.231279.\u2002\r\n[2]\tA. D. Shatrov, A. N. Sivov and A. D. Chuprin, \"Investigation of multifilar helical antennas with small radius and large pitch angle on basis of eigenmodes of infinite sheath helix,\" in Electronics Letters, vol. 30, no. 19, pp. 1558-1560, 15 Sept. 1994, doi: 10.1049\/el:19941099\r\n[3]\tJ. Wong and H. King, \"Broadband quasi-taper helical antennas,\" in IEEE Transactions on Antennas and Propagation, vol. 27, no. 1, pp. 72-78, January 1979, doi: 10.1109\/TAP.1979.1142033.\r\n[4]\tA. R. Djordfevic, A. G. Zajic, M. M. Ilic and G. L. Stuber, \"Optimization of Helical antennas [Antenna Designer's Notebook],\" in IEEE Antennas and Propagation Magazine, vol. 48, no. 6, pp. 107-115, Dec. 2006, doi: 10.1109\/MAP.2006.323359.\r\n[5]\tD. E. Baker, \u201cMeasured performance of a broadband matching section for peripherally fed helical antennas,\u201d The Transactions of the South African Institute of Electrical Engineers, vol. 76, no. 2, pp. 56\u201361, 1985.\r\n[6]\tA. R. Djordfevic, A. G. Zajic, M. M. Ilic and G. L. Stuber, \"Optimization of Helical antennas [Antenna Designer's Notebook],\" in IEEE Antennas and Propagation Magazine, vol. 48, no. 6, pp. 107-115, Dec. 2006, doi: 10.1109\/MAP.2006.323359.\r\n[7]\tA. Boothby, R. Hwang, V. Das, J. Lopez and D. Y. C. Lie, \"Design of Axial-mode Helical Antennas for Doppler-based continuous non-contact vital signs monitoring sensors,\" 2012 IEEE Radio and Wireless Symposium, Santa Clara, CA, 2012, pp. 87-90, doi: 10.1109\r\n[8]\tDun Wei Liao, Xin Yi Wang, Bo Zhou and Feng Wei, \"A novel impedance matching method of helix antenna,\" 2016 IEEE International Conference on Microwave and Millimeter Wave Technology (ICMMT), Beijing, 2016, pp. 771-773.\r\n[9]\tS. V. Savi\u0107, M. M. Ili\u0107 and A. R. Djordjevi\u0107, \"Design of internal wirebased impedance matching of helical antennas using an equivalent thin wire model\", International Journal of Antennas and Propagation, vol.2017, pp. 1-5, December 2017.\r\n[10]\tV. Wongpaibool, \"Improved Axial-Mode-Helical-Antenna Impedance Matching Utilizing Triangular Copper Strip for 2.4-GHz WLAN,\" 2008 International Wireless Communications and Mobile Computing Conference, Crete Island, 2008, pp. 869-873, doi: 10.1109\/IWCMC.2008.150. \r\n[11]\tM. Kgwadi and T. D. Drysdale, \"Parametric study of broadband tunable helix antenna matching,\" 2014 Loughborough Antennas and Propagation Conference (LAPC), Loughborough, 2014, pp. 128-131, doi: 10.1109\/LAPC.2014.6996337.\r\n[12]\tCST Microwave Studio, version 2018.","publisher":"World Academy of Science, Engineering and Technology","index":"Open Science Index 173, 2021"}