一种水下微弱回波信号的过零点检测方法

A Kind of Zero-crossing method for detecting Underwater small sine echo signals

通过大量仿真和实测目标回波数据检验，本文提出了微弱单频回波信号检测的过零点分析方法。该方法对输入信噪比的要求与单纯幅值判决相比，降低了14dB．它的特点是运算量少，耗时短，信号检测增益高，所需存贮单元少，特别适合于水下便携式检测设备及水中兵器的微弱信号的检测，该方法也可用于语音、地震、生物、医疗等领域单频弱信号的检测。

This paper proposes ' zero-crossing 'method to detect sine echo through a large amount of computer simulation and the test to some practically measured target echo data . The demand for input S/N ratio of this method is 14dB less than that of pure amplitude decision method . Its characteristics are little computational load , short working time , few saving units . It is suitable for underwater equipments which low power consumption. It is also can be used in the field of speech sounds 、earthquake 、medical treatment、biology and tec.