宦爱奇　刘　锋　王泽众

(1.海军航空工程学院　山东　264001)(2.海军装备研究院　北京　100249)



基于周期Wigner-Hough变换的线性调频连续波信号检测算法*

宦爱奇1刘锋1王泽众2

(1.海军航空工程学院山东264001)(2.海军装备研究院北京100249)

摘要提出了一种周期Wigner-Hough变换(PWHT)对线性调频连续波(LFMCW)信号的检测算法。分析了线性调频连续波信号的PWHT及其性质,并对无先验知识条件下的LFMCW信号检测问题进行研究,给出了基于PWHT的LFMCW信号检测流程。仿真验证了该算法由观测时间带来的检测性能增长与噪声方差不为1时的检测性能变化趋势。

关键词周期Wigner-Hough变换; 线性调频连续波; 信号检测

Linear Frequency Modulation Continuous Wave Radar Signal Detection Algorithm Based on Periodic Wigner-Hough Transform

HUAN Aiqi1LIU Feng1WANG Zezhong2

(1. Naval Aeronautical and Astronautical University, Yantai264001) (2. Naval Armament Research Institute, Beijing100249)

AbstractA linear frequency modulation continuous wave radar signal detection algorithm which was based on periodic Wigner-Hough Transform was proposed. Firstly, the properties of the periodic WHT of a linearly frequency modulated continuous wave signal were analyzed. Secondly, LFMCW signal detection with no prior knowledge was studied. Thirdly, the workflow of the application of the algorithm was proposed. Finally, the increase in detection performance by observation time and the detection performance variation trend when noise variance wasn’t 1 were verified by simulation.

Key WordsPWHT, linear frequency modulated continuous wave, signal detection

Class NumberTN95

1引言

低截获概率(Low Probability Intercept,LPI)雷达信号具有波形复杂、功率低、带宽宽等特点,雷达侦察接收机很难对其进行可靠的识别。而线性调频连续波(Linear Frequency Modulated Continuous Wave,LFMCW)信号是LPI雷达常采用的信号形式,它不仅具有良好的距离/速度分辨力和测量精度,还具有良好的抗干扰能力和低截获性能。在雷达侦察中,如何对这类信号进行快速有效地识别已成为一大难点,也是近几年电子侦察方向研究的一大热点[1]。

为了更好的处理此类信号,文献[2～5]、[6～11]分别基于镜像滤波器组(QMFB)、WHT、FRFT和Choi-Williams分布(CWD)等算法,对LFMCW信号的检测与参数估计问题进行了研究,但是效果都不理想。其中,QMFB不具抗噪功能,需要首先对信号进行消噪处理,导致信号检测与参数提取能力受消噪能力影响较大;由于受多分量LFM周期交叉项的影响,基于WHT和FRFT的方法在低信噪比条件下很难提取LFMCW的信号特征并进行识别,且在多分量连续波信号存在的条件下,不可避免地受到交叉项干扰;CWD可以避免交叉项的影响,但是它的时频分辨力下降比较严重,从而降低了LFMCW信号特征提取和识别能力。……