宽带正交调制器设计与实现

Design and Implementation of Broadband Quadrature Modulator

介绍了宽带正交调制器的工作原理和传统设计方法。针对宽带卫星通信系统中调制信号正交性误差对信号传输质量影响较大的问题,通过阻抗匹配、差分信号传输和接口电平功率控制等技术手段,对无源非线性器件的外围电路进行优化设计。使调制信号的EVM值提高了7%以上,在大幅提升宽带正交调制器的性能指标的同时,扩展了宽带正交调制器对本振功率、基带信号功率的适应范围。

This paper introduces the operating principle and traditional design methods of broadband quadrature modulator.In the broadband satellite communication system, the orthogonality deviation will influence significantly the transmission quality of modulation signals.In order to solve this problem,by using such technical methods as impedance matching,differential signal transmission, and in- terface level power control, this paper puts forward the optimization design scheme for peripheral circuit of passive nonlinearity devices. As a result,the EMV value of modulation signal is increased more than 7%, the performance index of broadband quadrature modulator is improve significantly, and the application range of broadband quadrature modulator on local oscillator power and baseband signal power is extended.