一种有源双平衡微波混频电路的设计与分析

A Design and Analysis of An Active Double Balance Microwave Mixer

采用系统分析的方法,从微波混频器基本原理入手,分析了本振反相型平衡混频器性能参数;在此基础上,采用芯片LT5522设计了一种有源双平衡微波混频器;对该接收机实物电路进行测试分析。设计的混频器在输入端添加了镜像抑制滤波器,在前级添加了低噪声放大器,因而使整个下变频电路具有良好的噪声系数,链路噪声系数小于1.2dB,结果满足要求。

The performance of local oscillator anti-phase balance mixer is analyzed by using the system anal- ysis method. Then, a double balance mixer is designed by adopting the LT5522 chip. Finally, the practical- ity circuits of a receiver are tested and analyzed. A mirror frequency suppression filter is configured at the input end of the mixer, and a low noise amplifier is configured at the input port. By doing so, the whole down-mixer circuits observe a better noise factor, and this noise factor is less than 1.2 dB of the whole cir- cuits to satisfy the needs.