变速目标的光子回波外差信号处理方法研究  

Signal Processing Method of Photon Echoes Heterodyne for Variable⁃Speed Target

作　　者：蒲梦瑶 胡以华 曲芳慧 张鑫源 董骁 Pu Mengyao;Hu Yihua;Qu Fanghui;Zhang Xinyuan;Dong Xiao(State Key Laboratory of Pulsed Power Laser Technology,College of Electronic Engineering,National University of Defense Technology,Hefei 230037,Anhui,China;Anhui Province Key Laboratory of Electronic Restriction,College of Electronic Engineering,National University of Defense Technology,Hefei 230037,Anhui,China;No.95438 Unit of PLA,Meishan 620000,Sichuan,China)

机构地区：[1]国防科技大学电子对抗学院脉冲功率激光技术国家重点实验室,安徽合肥230037 [2]国防科技大学电子对抗学院电子制约技术安徽省重点实验室,安徽合肥230037 [3]95438部队,四川眉山620000

出　　处：《中国激光》2023年第10期222-232,共11页Chinese Journal of Lasers

基　　金：国防科技大学科研计划项目重大项目(ZK18-01-02);国家自然科学基金(61871389);脉冲功率激光技术国家重点实验室基金(KY21C604);电子对抗学院基金项目(KY21C220);湖南省研究生科研创新项目(CX202200)。

摘　　要：变速运动目标的中频信号特征频谱具有连续集中的多频分量,且具有一定的多普勒展宽,在背景噪声和暗计数的影响下,光子回波外差信号的信噪比较低时,使用传统的信号处理方法得到的中频信号频谱以及时频分析特性效果较差。为提高信噪比,本文提出了将稀疏度自适应压缩感知和密度聚类相结合的信号处理方法,并采用该方法对变速目标的光子回波外差信号进行处理。该信号处理方法解决了变速目标频谱稀疏度K无法提前确定的问题,而且只需要较少的观测数据就可以重构信噪比较高的中频频谱。此外,该方法结合密度聚类算法对中频频谱进行了第二重去噪,大幅度减少了噪声分量。研究结果表明,该信号处理方法能够将信噪比提高一定幅度且多普勒展宽精度误差在10%以内,可以得到较为完整的重构中频信号频谱,同时较好地解决了信号时频分辨率较差的问题以及单光子探测等间隔时间序列造成的时频图中的倍频现象,得到了更好的时频特性描述。Objectives The research purpose and focus of this paper is to propose a new signal processing method that processes a photon echo heterodyne signal and can achieve a higher signal-to-noise ratio(SNR)intermediate frequency(IF)signal spectrum and signal timefrequency characteristics with an improved performance to improve the photon counting heterodyne radar speed measurement performance of variable-speed moving targets.Methods This study applies the adaptive sparse degree compression perception method to a variable-speed target heterodyne photon echo signal and solves the problem whereby the sparse degree of K can not be determined in advance.The reconstructed frequency spectrum has a relatively high SNR but error and some unfiltered noise are also found on the spectrum.Furthermore,according to the characteristics of concentrated and continuous Doppler spectrum components of the variable-speed target,density clustering is creatively applied to the denoising of the above-reconstructed spectrum,and the sparsity adaptive compression sensing and clustering algorithm are combined as a new heterodyne signal processing method of photon echoes.In this paper,the first part of the proposed signal processing method is to solve the frequency spectrum.This process is divided into four parts,namely compressed perception reconstruction of the IF spectrum,density clustering,denoising,and interpolation.First,the frequency spectrum is reconstructed by the sparsity adaptive matching pursuit(SAMP)algorithm according to the photon arrival time series,the IF signal spectrum is reconstructed,and compressed perception processing is performed.The lower amplitude of the spectrum component is assumed as noise,and only discrete signals whose amplitudes are significantly higher than noise are retained in the reconstructed IF spectrum.However,at this time,the reconstructed IF signal spectrum is not the final signal spectrum,and the noise signal with higher spectrum amplitude is still retained.Compared with the noise,the signal of the ideal spe

关 键 词：光谱学 光子外差 压缩感知 聚类去噪 多普勒测速 时频分析 

分 类 号：O439[机械工程—光学工程]