一种基于信号功率的水声通信线性调频同步信号自适应阈值检测算法

由于线性调频信号具有一定的抗多普勒效应能力，在水下突发通信中作为同步序列得到了广泛的应用。在对线性调频信号进行同步的过程中发现，当采用固定判决门限检测方法时，往往会造成检测概率的减小或者虚警概率的增大，针对这一问题，本文提出了一种根据信号功率，并在滑动窗口中进行比较判决，自动调整相关峰检测门限值的自适应算法。通过仿真和湖试验证，该方法性能良好，具有一定的实用价值。

An adaptive threshold detection algorithm for Linearly-Frequency Modulated signals based on signal power in underwater acoustic communication

Linearly-Frequency Modulated (LFM) signals have been widely used as synchronization sequence in underwater burst communication for its high tolerance of Doppler effect. However, the problem of detection probability decrease or false-alarm probability increase will be caused when constant threshold detection scheme is adopted in LFM synchronization process. To deal with this issue, this paper proposes an adaptive threshold algorithm which adjusts decision threshold automatically based on signal power in a slide window. Furthermore, extended simulation and lake experiment results indicate that the proposed algorithm has a good performance and is proper for practical applications.