The Influence of Magnetic Field on Antenna Performance in Plasma

A spacecraft loses all forms of communication, including global positioning system signals, data telemetry, voice communication and so on, when it enters the communication blackout phase. This becomes more and more critical with the development of reentry vehicle missions since radio blackout brings about many serious issues related to vehicle safety. This paper studies the influence of magnetic field on antenna performance in plasma. The results indicate that the effect of plasma on the antenna performance can be negligible when the magnetic field reaches a certain strength. This provides another way to solve the reentry blackout problem.     

0.12THz谐波混频器的设计与研究

在太赫兹通信、雷达、电子对抗、测量等系统中,所遇到的首要问题便是太赫兹波信号的频率变换,谐波混频器是太赫兹通信系统中最为核心的器件,其性能的好坏将直接决定接收系统和发射系统的性能,本文对0.12THz的二次谐波混频器进行理论分析,在理论分析的基础上对该混频器进行设计仿真,理论仿真结果表明0.12THz的二次谐波混频器的损耗小于8dB,并对于优化后的模型在RT/duroid 5880为电路基片上进行加工测试,测试结果表明本文设计的0.12THz二次谐波混频器衰减为7dB,已经达到了国际先进水平。     

基于拓扑优化的某全金属Vivaldi 天线轻量化设计

近年来,天线的轻量化设计受到普遍关注。随着优化理论和仿真技术的快速发展,基于拓扑优化的天线轻量化设计已成为重要的研究方向。文中以某全金属Vivaldi 天线为研究对象,运用拓扑优化基本理论,结合有限元仿真手段,对其天线单元进行了轻量化设计。仿真结果表明：通过轻量化设计,该天线在满足动态特性和辐射特性的前提下,其阵列的总质量下降了近15%,达到了预定要求,说明这是一种行之有效的轻量化设计方法.