基于FFT的突发扩频信号兼容快捕算法

Compatible fast acquisition algorithm for burst spread spectrum signal based on FFT

针对传统突发扩频信号捕获算法的缺陷,即无法自适应兼容处理不同同步头时长信号,提出了一种改进的基于FFT的突发扩频信号兼容快速捕获算法。根据不同时长信号的实际应用特性,利用同步头信号尾部对齐的格式特点,采用子矩阵形式存储不同时长信号的码相关结果,通过多支路并行捕获处理,实现突发信号的自适应兼容捕获。同时,通过矩阵的FFT运算同步实现全相干累积来提高信号载噪比,通过时频并行处理提高处理效率,最大限度地优化了弱信号条件的捕获性能。仿真验证表明,算法可以实现不同扩频信号的兼容快速捕获,研究为同步头时长不等的低载噪比信号提供了一种有效的兼容快速捕获方法。

An improved compatible fast acquisition algorithm for burst spread spectrum signal based on FFT is introduced for the imperfection of the traditional fast acquisition algorithm of burst spread spectrum signal that can't process different synchronization-head length adaptively and compatibly.According to the actual application feature of different duration signals,it takes advantage of that the synchronization sequences are aligned at the end and stores the code correlation results in the manner of matrixes.Then parallel processing is used to realize adaptive acquisition compatibly for burst spread spectrum signal.Meanwhile,through the FFT operation of matrixes can realize complete coherent accumulation to improve the signal-to-noise ratio.Time-frequency parallel processing is used to improve processing efficiency,so as to make the most of optimizing the acquisitive performance of weak signals.The simulation result proves that the method can realize compatible and fast acquirement of different spread spectrum signals.The research pnvides an effective method for compatible and fast acquirement of different synchronization-head low signal-to-noise ratio signals.