一种大步进伪码快速捕获方法的研究

在无线电导航系统中,低信噪比的情况下长伪码序列的快速捕获和重捕成为系统必须解决的一个重要问题.针对该问题,提出了一种大步进伪码快速捕获方法,并给出了大步进伪码快速捕获的原理和实现方法,详细分析了该方法的检测概率、虚警概率和平均捕获时间.该方法易于采用大规模集成芯片和数字信号处理算法实现且已经应用到实际接收机系统中,仿真结果和实践证明该方法具有较快的捕获速度,捕获灵敏度高,能够在低信噪比下稳定工作.

Research on large step code fast acquisition algorithm

In wireless navigation systems,rapid acquisition and re-acquisition of the low S/N long period PN code is a crucial challenge.To solve this problem, a new method of large step code fast acquisition is proposed.The probability of a false alarm,the probability of detection,and average acquisition time are discussed in detail.The algorithm is prone to work in field programmable gate array(FPGA) and digital signal processor(DSP) and has been used in practical receiver.Simulation results and practice show that this method can greatly decrease the acquisition time while improving the performance of acquisition in low SNR.