改进DLMS震动信号自适应滤波算法与FPGA实现  

Improved DLMS vibration signal adaptive filtering algorithm andFPGA implementation

作　　者：马翊翔 李剑[1,2] 贺斌 陈俞安 魏芦俊 Ma Yixiang;Li Jian;He Bin;Chen Yu′an;Wei Lujun(State Key Laboratory of Dynamic Testing Technology,Collaborative Innovation Center,North University,Taiyuan 030051,China;Shanxi Key Laboratory of Information Detection and Processing,North University,Taiyuan 030051,China)

机构地区：[1]中北大学省部共建动态测试技术国家重点实验室,太原030051 [2]中北大学信息探测与处理山西省重点实验室,太原030051

出　　处：《电子测量技术》2024年第20期117-123,共7页Electronic Measurement Technology

基　　金：国家自然基金面上科学基金(62271453);中央支持地方项目(YDZJSX2024D031);山西省青年学术带头人项目(2024Q022);山西省专利转化专项计划项目(202405004)资助。

摘　　要：在地下浅层爆炸震动信号滤波过程中,D-LMS步长固定,对时变信号处理不灵活,易引发梯度噪声放大现象,且其需要依赖有效信号或噪声的先验信息作为期望信号,在地下浅层震动测试中这些信号通常未知。针对上述问题,围绕地下浅层爆炸震动探测的需求,对自适应滤波算法进行了研究,结合归一化原理提出了改进D-LMS滤波算法,并将其与传统算法在收敛速度、滤波精度方面进行了仿真对比,结果表明此改进算法在震动测试自适应去噪中相比D-LMS算法滤波精度提高约2.3 dB,收敛速度提高约一倍。并将其部署于ZYNQ PL端,设计了延迟模块、步长模块、系数更新模块、滤波模块和误差计算模块,并封装成IP核,嵌入采集系统进行地下浅层震动外场试验,实验表明对实际震动信号,滤波后信号明显优于未滤波信号,证明了自适应滤波模块的有效性,实现了震动信号的实时片上自适应去噪,为地下浅层震动场重建提供了重要支撑。During the filtering process of explosion-induced vibration signals in shallow underground layers,the fixed step size of the D-LMS algorithm is not flexible enough for time-varying signal processing,which can easily lead to the amplification of gradient noise.Moreover,it relies on prior information about the effective signal or noise as the desired signal,which is usually unknown in shallow underground vibration testing.To address these issues and meet the needs of shallow underground explosion-induced vibration detection,an improved D-LMS filtering algorithm was developed based on normalization principles.This improved algorithm was compared with traditional algorithms in terms of convergence speed and filtering accuracy through simulations.The results showed that this improved algorithm achieved approximately 2.3 dB higher filtering accuracy and doubled convergence speed compared to the D-LMS algorithm in adaptive denoising of vibration testing.It was deployed on a ZYNQ programmable logic device,where modules for delay,step size,coefficient update,filtering,and error calculation were designed and encapsulated into an IP core.This core was integrated into the acquisition system for field tests of shallow underground vibrations.Experimental results demonstrated that the filtered signals were significantly better than unfiltered ones,confirming the effectiveness of the adaptive filtering module.This achieved real-time on-chip adaptive denoising of vibration signals,providing crucial support for the reconstruction of shallow underground vibration fields.

关 键 词：最小均方误差 延时最小均方误差 自适应滤波 震动探测 ZYNQ FPGA 

分 类 号：TN713.7[电子电信—电路与系统]