2015-11-25
浏览次数：430
报告题目：Time‐Varying Transmission Lines (TVTLs): Creating On-Chip Non-Reciprocity for Future Wireless Communications
时间：2015年12月1日（星期二）下午16:00~17:30
地点：逸夫人文馆报告厅
报告人：美国加州大学洛杉矶分校副教授/ IEEE Trans. Antennas Propagation副主编Yuanxun Ethan Wang
（主页：http://www.ee.ucla.edu/yuanxun-ethan-wang/）
报告摘要：
Modern wireless systems such as cognitive radios often require the RF front-ends to be broadband, low noise and software reconfigurable. A full-duplex RF front-end offers not only higher capacity than that of a half-duplex system, but also flexibility in band selections without being constrained by a frequency diplexer. The implementation of such systems, however, requires non-reciprocal components that operate over a broad bandwidth, with low loss and good isolation. Recently, Time-Varying transmission lines (TVTLs) have been utilized to achieve such broad non-reciprocity without using nonreciprocal magnetic material. A TVTL is a transmission lines whose characteristic impedance is a function of space and time and its non-reciprocity is realized by breaking the space-time symmetry of electromagnetic wave propagation.
报告人简介：
Dr. Yuanxun Ethan Wang received the B.S. degree in Electrical Engineering from University of Science and Technology of China (USTC), Hefei, China in 1993, and the M.S. and the Ph.D. degrees in electrical engineering from University of Texas at Austin, in 1996 and 1999. He became an Assistant Professor with the EE department of UCLA since Nov. 2002 and is now an Associate Professor with the same department. Dr. Wang is a senior member of IEEE and an associate Editor of IEEE Transactions on Antennas and Propagation. He has published more than 100 journal and conference papers. His research is in the general area of microwave systems with emphasis on the front-ends including antennas, phased arrays, high performance RF transmitters and receivers. His researches blend digital technologies and concepts into RF design, which often leads to novel antenna and circuit configurations with performances beyond the conventional bound. Dr. Wang is the director of the Digital Microwave Lab and the Center for High Frequency Electronics in the Electrical Engineering Department of UCLA and the leader of the antenna thrust in National Science Foundation funded Engineering Research Center – Translational Applications of Nanoscale Multiferroic Systems (TANMS).
报告题目： 时变传输线：未来移动通信中的片上非互易性研究
时间：2015年12月1日（星期二）下午16:00~17:30
地点：逸夫人文馆报告厅
报告人：美国加州大学洛杉矶分校副教授/ IEEE Trans. Antennas Propagation副主编Yuanxun Ethan Wang
（主页：http://www.ee.ucla.edu/yuanxun-ethan-wang/）
报告摘要：
在认知无线电等现代无线通信系统中，射频前端器件应具有宽带、低噪声和软件可重构等特点。全双工射频前端不仅能比半双工的器件提供更大的容量，还因其不受频率双工器的影响而具有更大的频段选择自由度。但这类全双工系统要求使用宽带、低损耗和高隔离的非互易器件。在最近的研究中，时变传输线（TVTLs）被用于设计宽带非互易器件。这种新方法不再采用非互易的磁介质进行设计。时变传输线的特征阻抗与时间和空间密切相关，其非互易特征通过打破电磁波传播过程中的时空对称性予以实现。
报告人简介：
王元勋博士于1993年毕业于中国科技大学，获学士学位。其后他在美国德州大学奥斯汀分校获得硕士（1996）和博士（1999）学位。他随后加入美国加州大学洛杉矶分校，先后任职助理教授和副教授。王元勋博士是美国电气电子工程师学会（IEEE）高级会员，也是IEEE Transactions on Antenna Propagation的副主编。他已发表了100多篇期刊与会议论文。王博士的研究领域包括微波系统的各个方面，主要研究方向为射频前端器件，包括天线、相控阵、高性能射频收发器等。他将数字处理技术与射频设计相融合，设计了多种新颖的射频器件，这些器件的性能远远超过了传统器件的性能上限。
王元勋博士是加州大学洛杉矶分校数字微波实验室和高频电子中心的主任，同时也是美国国家科学基金会纳米尺度多铁性系统转化应用工程研究中心（TANMS）天线分部的负责人。