基于FFT的时频并行捕获算法研究

Proposing a Fast Time-Frequency-Domain Parallel Acquisition Algorithm Based on FFT

在扩频通信系统中,PN码的捕获是系统正常工作的前提。为了进一步实现快速捕获,研究了基于FFT的时频并行捕获算法,利用FFT实现频域并行捕获、利用多通道实现码域并行捕获。理论推导验证了该算法的正确性,分析了该算法捕获精度、捕获速度、实现复杂度以及低通滤波效应。仿真结果进一步验证了该算法捕获的正确性。基于FFT的时频并行捕获算法在不降低精度的前提下,可以有效提高捕获速度。

The acquisition of PN codes plays an important part in the Spread Spectrum Communication Systems.In order to accelerate the procedure of acquisition,we study parallel acquisition algorithm,which concurrently performs frequency domain searching with FFT and time domain searching with multi channels.And the theoretical deduction result validates the correctness.Further analysis on precision,speed,complexity and low-pass effect reveals the superiority.Finally we demonstrate the feasibility from the aspect of simulation.From the theoretical analysis and simulation verification,we can conclude that the proposed parallel acquisition algorithm can accelerate the acquisition without the sacrifice of precision.