弹性物体在混响背景下的散射信号检测

Scattering Signal Detection of Elastic Object in Reverberation Noise

混响是主动声呐的主要背景干扰,是由发射信号引起的,其谱结构与发射信号也具有一定的相似性,是一种非平稳的有色干扰噪声。特别是在浅水情况下,强大的混响干扰尤其严重。而在实验数据中有时并没有获得发射声信号的取样。本文采取一种尝试,截取一段高信混比回波作为发射信号来考虑,同时截取纯混响叠加到回波信号上,以模拟低信混比的情况,在混响自回归(AR)模型的基础上研究混响的预白化处理,并将预白化处理后的信号用于匹配滤波器的信号检测。

Reverberation is the dominant background interference of active sonar, it is caused by transmitted signal, and its spectra has some comparability with transmitted signal. Reverberation is non-stationary colored disturbance noise. In shallow sea, the strong reverberation interference is especially considerable. But, sometimes there is no clear transmitted signal in our experiment data. In this paper, we try to extract a piece of evident echo and consider it as transmitted signal. In the mean while, we extract the reverberation signal plus received signal to simulate low signal reverberation ratio signal. Pre-whiten processing is studied based on reverberation autoregressive （AR） model. The pre-whiten processed signal is used in matched filtering signal detection.