Welch算法在弱信号检测中的性能分析

为了将微弱的潜艇信号从复杂的噪声背景环境中检测出来,研究分析了经典功率谱分析中周期图法和Welch算法的算法原理、性能及估计质量。选择合适的窗函数和重叠点数,基于Welch算法对2FSK调制信号进行了的定量分析。以MATLAB为仿真平台,研究了周期图法和Welch算法对潜艇常用的4种调制信号的检测性能,验证了加Blackman窗函数和512点重叠的Welch算法可以达到更好的方差性能和谱分辨率,并验证了该算法在低信噪比条件下检测信号的可行性。结果表明上述参数条件下的Welch检测算法,可以达到较好的分辨率和方差性能,为潜艇信号检测的工程实际应用提供了一种可借鉴的方法。

Performance Analysis of Welch Algorithm in Weak Signal Detection

In order to detect weak submarine signals from complex noisy background, the principle, performance and estimation quality of periodic graph method and Welch algorithm in classical power spectrum analysis were studied and analyzed. The 2 FSK modulation signal was quantitatively analyzed based on Welch algorithm by choosing appropriate window function and overlap point number. Using MATLAB as the simulation platform, the detection performance of periodic graph method and Welch algorithm for four kinds of modulation signals commonly used in submarines were studied. It is verified that the Welch algorithm with Blackman window function and 512 points overlap can achieve better variance performance and spectral resolution, and the feasibility of detecting signals under low signal-to-noise ratio is verified. The results show that the Welch detection algorithm under these parameters can achieve better resolution and variance performance, and provide a reference method for the practical application of submarine signal detection.