C波段反射型线性360°模拟移相器的设计

Design for C-Band Linear Reflection-Type 360° Analog Phase Shifter

为调制射频信号在传输过程中引入的相移,设计了中心频率为4.0 GHz的反射型线性360°模拟移相器,利用分支线型定向耦合器和变容二极管实现360°移相,采用两个双分支定向耦合器级联构成三分支定向耦合器。同时采用带有串联传输线和短路终端的反射终端电路,使电路更易调节,以获得最佳线性度和最大带宽。最终给出了移相器的线性度和插入损耗的仿真和测试结果。结果表明,该移相器移相范围为360°,带宽为200MHz,中心频率移相误差小于15°,插入损耗波动小于3.5 dB。

In order to modulate the phase shift of RF signal generated in the process of transmission, a reflection- type 360° analog phase shifter operating at 4.0 GHz is designed. It uses a branch-line coupler and two varactor- diode circuits to achieve 360° phase shift. It uses a three-branch branch-line coupler instead of a two-branch branch-line coupler to increase the bandwidth. And a new reflective load is used to get more freedom of adjustment of the linearity and bandwidth. The results of simulation and measurement on the linearity and insertion loss are presented. The results show that the design has a 360° phase shift range and a 200 MHz bandwidth with a 15° phase shift error and a 3.5 dB insertion loss at the center frequency of 4.0 GHz.