基于小波降噪的雷达时频信号互相关测速算法  

Wavelet denoising based cross-correlation velocity detection algorithm of radar time-frequency signal

作　　者：李佳[1] 曹林[1] 王东峰 付冲[3] LI Jia;CAO Lin;WANG Dongfeng;FU Chong(Department of Communication Engineering,Beijing Information Science&Technology University,Beijing 100101,China;Beijing TransMicrowave Science and Technology Co.,Ltd.,Beijing 100018,China;School of Computer Science and Engineering,Northeastern University,Shenyang 110004,China)

机构地区：[1]北京信息科技大学通信工程系,北京100101 [2]北京川速微波科技有限公司,北京100018 [3]东北大学计算机科学与工程学院,辽宁沈阳110004

出　　处：《现代电子技术》2020年第9期14-20,共7页Modern Electronics Technique

基　　金：国家自然科学基金(61671069)。

摘　　要：为提高基于FMCW体制的双波束车流量雷达的测速精度,对其信号特征进行分析,结合Burg和广义互相关理论,提出基于小波降噪的时频信号互相关测速算法(CC-BWT)。首先,利用最大熵功率谱估计的Burg方法得到雷达回波的频谱信息,通过CFAR检测出目标车辆后提取车辆的时频信号;然后,对时频信号进行小波分解,以改进的阈值函数作为降噪依据进行信号重构,之后两路信号做互相关,估计出时延,从而测得车辆速度。结合仿真和实测数据,并与相位法和双谱法进行对比,验证了该算法的测速准确度达到96%以上且算法鲁棒性好。The signal features of FMCW(frequency modulated continuous wave)are analyzed to improve the accuracy of FMCW system based speed detection of dual-beam vehicle flowrate radar. In combination with the Burg and generalized crosscorrelation theory,a time-frequency signal cross-correlation algorithm based on Burg and wavelet transform(CC-BWT) is proposed. Firstly,the frequency spectrum information of radar echo is obtained with the Burg method based on the maximum entropy power spectrum estimation and the time-frequency signal of the vehicle is extracted after the target vehicle is detected with CFAR. And then,the time-frequency signal is subjected to wavelet decomposition to reconstruct the signal by taking the improved threshold function as the denoising basis,then the two signals are correlated for the estimation of the delay and the vehicle speed is obtained finally. It is compared with the phase method and the bispectrum method in combination with the simulation and measured data. The comparison results verify that the speed detection accuracy of the algorithm is above 96% and its robustness is good.

关 键 词：互相关测速 时频信号提取 小波降噪 最大熵谱估计 信号重构 车辆测速 

分 类 号：TN957.51-34[电子电信—信号与信息处理]