一种非平稳噪声背景下的线谱相干检测方法  

A Tone Coherent Detection Method in Non-stationary Noise Background

作　　者：马世龙 徐雅南[1] MA Shilong;XU Yanan(Hangzhou Applied Acoustic Research Institute,Hangzhou 310012,China)

机构地区：[1]杭州应用声学研究所,浙江杭州310012

出　　处：《数字海洋与水下攻防》2021年第3期188-194,共7页Digital Ocean & Underwater Warfare

摘　　要：舰艇目标航行时往往向水中辐射大量线状谱结构的声波信号,线谱信号检测对舰艇目标的被动探测至关重要。实际水下环境噪声常表现为时域非平稳噪声,常规离散傅里叶变换类线谱检测方法时域积分时,不可避免会引入非平稳噪声背景中出现的短时强干扰噪声,使积分结果中线谱信噪比大幅降低,线谱检测性能急剧恶化。为解决上述问题,对分段离散傅里叶变换结果进行幅度归一化,补偿分段线谱信号间相位差,提出了一种非平稳噪声背景下的线谱相干检测方法。仿真结果表明,相比常规DFT类线谱检测方法,所提方法能够降低时域非平稳背景噪声起伏影响,具有更优的非平稳噪声背景下线谱检测性能,并能获得对线谱信号的相干处理增益。Ships in voyage usually radiate a large number of tonal signals,which are significant for the passive detection of ship targets.The actual underwater environment noise usually manifests as time-domain non-stationary noise.The short-term strong component in non-stationary noise is inevitably introduced into the time-domain integration process of Discrete Fourier Transform(DFT)used for tone detection.The signal-to-noise ratio of tone in the integration result is greatly reduced,and the tonal signal detection performance has deteriorated sharply.To solve the above problem,amplitude normalization is conducted on the processing of DFT results,and the phase difference between segmented tonal signals is compensated.Then,a coherent tone detection method in non-stationary noise is proposed.Simulation results show that the proposed method can reduce the influence of time-domain non-stationary noise fluctuations.Compared with traditional DFT-like methods,the proposed method has better tone detection performance in non-stationary noise background,as well as a coherent processing gain of the adjacent data segments.

关 键 词：线谱检测 非平稳噪声 幅度归一化 

分 类 号：TP391.7[自动化与计算机技术—计算机应用技术]