直接变频接收机性能分析

On performance of Direct Converting Receiver

本文对直接变频接收机中正交矢量检测法进行了误差分析，讨论了由于接收机同相与正交两支路的增益差异、相位误差、本振泄漏及直流偏置导致其性能恶化的结果。为了实现ＧＭＳＫ信号解调，接收机中ＤＳＰ实现了调制信号的误差频谱估计、位同步恢复及译码。最后，用计算机模拟方法对该接收机性能进行了比较评价。

In this paper,error of quadrature vector detector used in direct converting receiver is analyzed and performance deterioration caused by gain error,phase error,local oscillation leak or DC offset on receiver's inphase and quadrature channels is discussed.To demodulate GMSK signal,DSP is used in receiver to achieve error spectrum estimation,bit synchronization recovery and decode.Finaly,comparison of this receiver performance based on computer simulation is presented.