基于可重构寄生阵列的封闭空间微波能量传输

Microwave Power Transmission in Enclosed Space Based on Reconfigurable Parasitic Arrays

针对航天器内部空间等封闭环境下电磁波的多径传播特性和阵列天线单元间的耦合效应,本文研究采用寄生阵列,通过控制寄生阵列单元负载的电抗实现高效率微波无线能量传输的方法。通过多端口微波网络建模,分析了寄生阵列天线方案相较于传统相控阵天线方案的能量传输性能和效率最大化机理。设计实现了基于射频开关切换的可调反射负载,并在此基础上形成了寄生阵列反射负载自动控制系统和传输效率优化程序。基于该系统和程序,在1m边长立方体的金属边界封闭空间实验环境下,测试了不同单元数可重构寄生阵列无线能量传输的性能和快速优化方法。测量结果表明增加寄生天线单元数目能够显著提高能量传输效率,从而提供了可重构寄生阵列传能技术实用化的一种有效途径。

Electromagnetic fields in fully-enclosed space such as spacecrafts and engine compartments exhibit strong standing wave pattern and multipath effects,which may lead to strong coupling among antenna array elements and make the conventional phased array not the best approach for wireless power transmission.This paper studies a method of efficient microwave power transmission in fully-enclosed space by employing reconfigurable parasitic antenna array with tunable reactive loads.Phased array and parasitic array are analyzed and compared with each other based on microwave network modeling.Tunable reactive loads are implemented for parasitic antenna elements using radio frequency(RF)switches,which enable reconfiguring microwave power transmission in real time.Experiments are conducted in a cubic box with size of 1 cubic meter and made of aluminum walls.Experimental results demonstrate that reconfigurable parasitic array can achieve high wireless power transmission efficiency in fully-enclosed space.To be specific,the power transmission efficiency measured in this paper is greater than 60%in most of the scenarios.