Sound as the most effective physical means of long-range underwater detection and communication. Currently international and domestic has developed a variety of sonar equipment ( such as side-scan sonar, synthetic aperture sonar, self-propelled variable depth sonar, etc. ) for detecting underwater targets. 声是水下远距离探测、通讯的最有效的物理手段,目前国际国内已发展装备了各种声纳(如侧扫声纳、合成孔径声纳、自航式变深声纳等)用于探测水下目标。