The comparison of underwater acoustic FM speech communication methods in shallow water channels
- 海洋环境－已发表论文 
水声语音通信在海洋工程、海洋科考、水下搜救等领域具有广泛应用。与单边带通信、数字编码调制通信相比,调频水声语音通信具有实现简单方便、抗幅度衰落性能好的特点,但浅海水声信道具有的复杂多径效应及噪声严重影响其获得的语音音质,容易出现语音含混、语义难辨等问题。本文通过浅海不同距离、不同多径信道下的海试实验比较了采用非线性解调法和正交解调法的调频语音通信性能,并通过客观语音质量评估PESQ（Perceptual evaluation of speech quality）方法对调频水声语音通信音质进行量化评估。Underwater acoustic speech communication plays an important role in mar/ne engineering, marine research, underwater search and rescue, and related fields. Compared with the classic single side band communication and digital code modulation communication, frequency modulation （FM） underwater acoustic voice communication has a good performance in amplitude fading resistance and low implementation complexity. However, shallow water channels featured by complicated multipath and noise will seriously degrade the speech communication quality of FM systems, leading to the problem of ambiguous speech and semantic ambiguity. This paper compares the performance of the underwater acoustic FM speech communication system used nonlinear demodulation method and orthogonal demodulation method by the field experiment in different shallow water channels, and performs quantitative assessment to the speech communication quality through PESQ （Perceptual evaluation of speech quality） method.