学术报告会通知 题 目: Antenna researches against common knowledge The mode of an Ultra-Low Profile Dipole antenna and research extension to practical antennas 报告人: Tadashi Takano ( Nihon University, Department of Electronics and Computer Science ) 时 间: 2012年3月8日(周四)上午10:00-11:30 地 点: 东南大学(四牌楼校区)李文正楼6楼614会议室 主 办: 东南大学毫米波国家重点实验室 IEEE AP-MTT-EMC Joint Nanjing Chapter 江苏省电子学会天线与微波专委会
摘 要:
Keywords: ultra-low profile dipole, metal reflector, close proximity, impedance matching, current distribution, novel balun, unbalanced single feed, parasitic conductor, When a dipole located above a metallic plate, the electromagnetic field distribution is determined to satisfy the boundary condition that the tangential electric field should be zero on the plate. The situation is well described in consideration of the image element, which is located at the conjugate position of the actual element with opposite polarity. They say that the summation of the two components will be added in phase to give the maximum gain of 8.2 dBi with the separation of λ/4, and out of phase to give a null in the proximity case. It was a common knowledge for antenna engineers. On the other hand, our theoretical and experimental study shows this is false and the gain in the proximity case reaches 9.0 dBi. The remaining problem is the matching between the dipole element and a feed line. This matching should include not only the impedance also the current distributions on both of the radiating element and the feed line. We have solved this problem by a novel balun, which is formed by processing the coaxial line. Moreover, the configuration is simplified to be more convenient. All these researches were originated from actual needs, and expanded according to my curiosity as a researcher. I will describe the research process as well as the research results. 报告人简介: Dr. Takano was born in Tsukuba, Japan, in 1945. He received the B.S., M.S. and Ph.D. degrees in electric and electronics engineering from the University of Tokyo, in 1967, 1969 and 1972, respectively. In 1972, he joined the Electrical Communication Laboratories of Nippon Telegraph and Telephone Public Corporation (NTT). In 1984, he moved to the Institute of Space and Astronautical Science, Japan (ISAS), which was a part of the University of Tokyo and was again reorganized as a part of Japan Aerospace Exploration Agency (JAXA) in 2004. He was a professor in the Graduate School of the University of Tokyo from 1991 to 2007. In 2008, he retired JAXA, and was awarded Emeritus Professor. He moved to Nihon University in 2008, and is now a professor in Department of Electronics and Computer Science. His current research interests include antenna engineering, radio-wave and optical-wave applications and natural hazard detection technology. He received the Yonezawa Award 1975 and the Excellent Paper Award 1992, both from the Institute of Electronics, Information and Communication Engineers (IEICE) of Japan, the 1983 President Award and the 1983 Kajii Award both from NTT, the 1998 Prize of Japan Society for the Promotion of Machine Industry, and iWAT2010 Best Paper Prize. Dr. Takano is a member of IEEE (Fellow), URSI, IEICE (Fellow), Institute of Electrical Engineers of Japan, Japan Society for Aeronautical and Space Sciences, Japanese Rocket Society, American Geophysical Union, and Seismological Society of Japan. Professor Nihon University, Department of Electronics and Computer Science 7-24-1 Narashino-dai, Funabashi 274-8501 Japan Tel.+81-47-469-5529 Fax.+81-47-467-9683 E-mail takano@ecs.cst.nihon-u.ac.jp |
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