海洋环境中基于WVD的LFM信号检测方法

A New Approach with Wigner-Ville Distribution Based On LFM Signal Detection in the Ocean

海洋环境中弱信号的谱与海杂波的谱相混叠 ,目标和背景的位置差异很小 ,经典的频域或空域处理对海杂波中弱信号的检测难以奏效。鉴于Wigner-Ville分布 (WVD)对线性调频信号 (LFM )具有时频聚集性这一特点 ,提出了一种海洋环境中基于WVD的LFM信号检测方法。利用雷达采集的真实海杂波数据 ,在不同信杂比的条件下 ,研究了该方法与经典频域法在信号检测中的差别。通过实验分析 ,与经典方法相比 ,该方法具有明显的优越性 ,且信杂比达到 -14 . 3dB时 ,其仍能很好地对信号进行检测。

Generally speaking, the spectrum of feeble signal folds the spectrum of sea clutter, and the location discrepancy between the target and its surroundings is small. So it is difficult for the classical processing in the frequency domain or space domain to detect the feeble signal in the ocean. This paper presents a new approach with Wigner Ville distribution based on the linear frequency modulation signal detection in the ocean whereas WVD has the time frequency local characteristic for LFM signal. It studies the difference between the new approach and the classical frequency approach for signal detection using the real data of the sea clutter collected by the radar in the condition of the several signal clutter ratios. The results show that the new approach has evident advantages compared with the classical approach. When the signal clutter ration is -14.3dB, it still detects the target effectively.