微波功率器件的滤波器测试电路

在微波电路原理和半导体器件物理的基础上,设计和模拟了三种用于微波功率器件的测试电路,并且设计了与之配套的测试夹具.采用矢量网络分析仪对该测试电路和夹具,在3～8GHz范围内进行了小信号测试.模拟和测试结果表明,采用阶梯阻抗滤波器偏置网络的测试电路性能较好,比采用扇形线偏置网络的测试电路具有更宽的带宽.该滤波器偏置电路能够用来在整个C波段,即在4～8GHz内对微波功率器件进行测试.但是,微带叉指耦合电容没有起到取代贴片隔直电容的目的,原因是该结构对参数精度要求高,而PCB制作工艺无法满足这个要求.

A Test Circuit with Microstrip Filter for Microwave Power Device

With the principles of microwave circuits and semiconductor device physics, three kinds of microwave power device test circuits are designed and simulated, whose properties are evaluated by a parameter network analyzer within the frequency range from 3 to 8GHz. The simulated results verify that the test circuit with stepped-impedance filter bias network has a larger bandwidth than that with the radial stub. A microstrip interdigital capacitor is used in the third test circuit to replace the DC block,however,which does not show its advantage during the test frequency band. Based on the simulated results, the stepped-impedance filter test circuit can be used to evaluate microwave power devices in the whole C band,namely from 4 to 8GHz.