电小天线匹配网络中负阻抗变换器的研究

Study on negative impedance converter used in matching network for electrically small antennas

根据非福斯特电路的负阻抗变换特性，研究了有源宽带匹配网络。采用晶体管设计负阻抗变换器，结合传输矩阵对网络电路进行了分析。通过仿真和实验实现了在 10~100 MHz 的负电抗变换。结果表明，该电路 20~60MHz 转换效率大于 90%，测试结果与模拟结果基本一致，验证了负阻抗变换器的可行性和有效性。利用该电路结构能够对电小天线进行宽带匹配，提高天线的工作带宽和辐射性能。

The active broadband matching network was studied according to the property of non-Foster circuits to convert to negative impedance. The network circuit was analyzed with the application of transistors in negative impedance converter （NIC） design, and in combination of the transmission matrix. The negative reactance conversion was realized within 10-- 100 MHz in the simulation and the experiment. Results show that the circuit converter efficiency is higher than 90% within 20--60 MHz. The experiment result is generally consistent with the simulation result and verifies NIC＇s feasibility and validity. The circuit structure could be applied to the broadband matching for electrically small antennas, thus to enhance the bandwidth and radiation.