一种基于恒虚警检测量的双判决帧同步方法

帧同步是突发无线通信系统中的重要技术环节，其虚警概率、检测概率对系统的整体性能有重大影响。文中针对能量检测算法在强干扰条件下虚警概率过高的问题，构造了一种具有恒虚警特性的随机变量，并推导了该变量的检测概率、虚警概率的解析表达式。该变量对干扰功率的变化不敏感，具有区分同步信号与突发强干扰信号的特点。基于所构造的新的随机变量提出了一种双重判决低虚警率帧同步算法，仿真结果表明该算法可有效降低系统的虚警概率，为帧同步信号的设计提供了参考。

Double-Decision Frame Synchronization Algorithm based on Constant False Alarm Variable

Frame synchronization is essential in burst wireless communication system. The false alarm prob-ability and detection probability have great impact on overall system performance. This paper focuses on solving high false alarm probability problem of traditional energy detection algorithm under strong interfer-ence conditions, and describes the construction of random variables with CFAR characteristics. Analytic expressions of detection probability and false alarm probability are derived. The variable is insensitive to the variation of interference signal power, and can distinguish true synchronization signal from strong inter-ference signal. Based on the new random variable, a double-decision frame synchronization algorithm is presented. Simulation results show that this algorithm can effectively reduce the false-alarm probability of the system.