S波段高精度快速倒相开关设计

Design of S-band bi-phase modulator with high speed and accuracy

摘要: 倒相开关是能量倍增器法（SLED）脉冲压缩系统中的关键器件，它的倒相精度和开关速度对脉冲压缩系统的性能有重要影响。设计了一种工作在S波段的精度可调、响应迅速的微带反射式倒相开关，并对其进行了理论分析，电路结构设计和仿真研究。对倒相开关的反射终端进行了改进设计，利用一个变容二极管来代替传统的并联枝节电路，通过调节变容二极管的偏置电压改变反射终端的反射系数，从而实现对倒相相位的精确调节。仿真结果表明，倒相开关响应时间约4 ns，且通过调节变容二极管偏置电压可以在一定范围内调节倒相精度。

Abstract: Bi-phase modulator is one important component in SLAC energy doubler (SLED) pulse compression systems. Performance parameters such as precision and speed of phase shift have significant impact on SLED. In this paper, an S-band bi-phase modulator with fast speed and adjustable accuracy is presented. Precision of the phase shifter is related to two parallel varactors, controlled by bias voltage. The simulated results show that the proposed bi-phase modulator has a fast switching speed of 4 ns and a high phase shift accuracy.