잔향 평활화와 위너 마스크를 활용한 비음수 행렬 분해 기반 능동소나 잔향제거 기법의 후처리 방법

In this paper, we present a study on improving the performance of active sonar reverberation suppression based on Non-negative Matrix Factorization (NMF). NMF is a technique that decomposes a nonnegative matrix into the product of two non-negative matrices. In reverberation suppression, this method decomposes the magnitude spectrogram of the input signal into two components: the target echo and the reverberation matrices. While conventional approaches utilize only the separated target echo matrix to recover the desired signal, this study proposes a post-processing method that utilizes both the target echo and reverberation components to enhance reverberation suppression performance. Specifically, the proposed method smooths the reverberation component and constructs a Wiener mask to suppress reverberation. The effectiveness of the proposed method was verified through simulations, demonstrating an improvement in the signal-to-noise ratio of up to 4 dB compared to conventional techniques.