同相正交信号相位失衡补偿方法研究  

Research on Compensation Method of Phase Imbalance of In-Phase and Quadrature Signal

作　　者：向景睿 田书林[1] 王厚军[1] 孟婕 栗钰博 XIANG Jingrui;TIAN Shulin;WANG Houjun;MENG Jie;LI Yubo(School of Automation Engineering,University of Electronic Science and Technology of China,Chengdu611731)

机构地区：[1]电子科技大学自动化工程学院,成都611731

出　　处：《电子科技大学学报》2023年第4期523-529,共7页Journal of University of Electronic Science and Technology of China

基　　金：中央高校基本科研业务费(ZYGX2020ZB003,ZYGX2020ZB002,ZYGX2020J012);四川省重大科学仪器设备专项(2019ZDZX0041,2019ZDZX0037)。

摘　　要：零中频接收机存在正交混频器电路中同相/正交(I/Q)信号失衡的问题,导致接收机的镜像抑制能力急剧下降,系统的动态范围受到影响。设计了一种计算并补偿I/Q信号线性相位失衡的方法,对解调后的I/Q两路基带信号进行互功率谱及其相位谱的计算,利用三点法进行相位解缠,根据解缠后的群延时差和相位偏置设计分数延时滤波器,进行相位补偿,还原出消除I/Q失衡后的时域信号。经仿真及硬件平台实验测试,该方法补偿效果好,实现简单、算法复杂度低、实时性高。The zero-IF receiver has I/Q imbalance in the quadrature mixer circuit,which leads to a sharp decline in the receiver's image rejection capability,and the signal-to-noise ratio and dynamic range of the system are affected.This paper designs a method to calculate and compensate the linear phase imbalance of I/Q signal.ADC sampling and Fourier transform are performed on the demodulated I/Q two-way baseband signals,and then the single-side spectrum is taken to calculate the cross-power spectrum and the phase spectrum of the cross-power spectrum.The three-point method is used for phase unwrapping,the phase compensation is performed according to the unwrapped group delay difference and phase offset,and finally the time domain signal is restored.After testing,the method has good compensation effect,simple implementation,low algorithm complexity and high real-time performance.

关 键 词：I/Q不平衡 线性相位失衡 相位解缠 零中频 

分 类 号：TN713[电子电信—电路与系统]