2025年03期 v.46 1-8页
王宗伟1 范超1 耿建强1 成丽燕2
（1.成都振芯科技股份有限公司，四川 成都 610000
2.电子科技大学集成电路科学与工程学院，四川 成都 610000）
摘要：针对宽带零中频接收端因IQ不平衡，影响信号正常解调的问题，提出一种基于前后向线性预测的宽带零中频IQ不平衡校准算法。首先，利用前后向线性预测误差均方值之和最小化准则分别估计I、Q通路上频率相关的脉冲响应特性；然后，通过递归计算得到差异滤波器系数；最后，基于信号二阶统计特性估计本振相位差，并在数字端完成IQ不平衡补偿。仿真结果表明，该算法相较于SAM算法、TPM算法，具有更好的镜像抑制比和矢量幅度误差。实测结果进一步表明，该算法实现简单，可有效提升信号解调性能。
关键词：宽带零中频接收机；IQ不平衡校准；前后向线性预测；差异滤波器；本振相位差
中图分类号：TN929.5; TN911.7 文献标志码：A 文章编号：1674-2605(2025)03-0001-08
DOI：10.12475/aie.20250301 开放获取
Wideband Zero Intermediate Frequency IQ Imbalance Calibration Algorithm Based on Forward and Backward Linear Prediction
WANG Zongwei1 FAN Chao1 GENG Jianqiang1 CHENG Liyan2
(1.Chengdu Corpro Technology Co., Ltd., Chengdu 610000, China
2.School of Integrated Circuit Science and Engineering, University of Electronic Science and
Technology of China, Chengdu 610000, China)
Abstract: To address the issue of signal demodulation impairment caused by IQ imbalance in wideband zero-IF receivers, a wideband zero intermediate frequency IQ imbalance calibration algorithm based on forward and backward linear prediction is proposed. First, the frequency-dependent impulse response characteristics of the I and Q branches are estimated by minimizing the sum of mean squared forward-backward linear prediction errors. Then, the differential filter coefficients are computed recursively. Finally, the local oscillator phase mismatch is estimated based on the second-order statistical properties of the signal, and IQ imbalance compensation is implemented in the digital domain. Simulation results demonstrate that compared with the SAM algorithm and TPM algorithm, the proposed algorithm achieves superior image rejection ratio and vector magnitude error. Experimental results further confirm that the algorithm features simple implementation and effectively enhances signal demodulation performance.
Keywords: wideband zero intermediate frequency receiver; IQ imbalance calibration; forward and backward linear predic- tion; difference filter; local oscillator phase difference
