一种基于比特量化的GPS并行码捕获算法

An Improved Parallel Code Phase Search Acquisition Algorithm Based on Bit Quantification for GPS Signals

针对GPS L1信号的软件接收机(SDR)的快速捕获问题,设计了GPS信号并行码相位搜索捕获的优化算法。首先分析了FFT并行码相位搜索捕获的理论模型,由本地C/A码功率谱频谱分布特点,使用前半频域范围内的信息,进行算法的初步优化;在此基础上采用比特量化方法量化数据信号,使单个计算机储存单元存储多路二进制量化数据,实现对多路数据的并行处理。实验证明改进的并行码相位搜索捕获算法极大地提高了捕获速度,是改进前的5倍,尽管有较少信号强度的衰减,但不影响捕获的正确性,实现了GPS信号的快速捕获。

An optimized algorithm is designed to improve nal, which applies to soft-defined GPS receiver for parallel code phase search acquisition for GPS L1 sigfasting acquisition. In the following, the model of parallel code phase search acquisition algorithm using FFT is analyzed. By the characteristics of the signal power spectrum, the algorithm is optimized by using the first half of spectrum information. Subsequently, bit quantification method is used to achieve parallel data processing by storing multi-channel data to a single memory unit. The result shows that the modified algorithm improves acquisition speed five times by decreasing little signal-noise ratio, and achieves fast acquisition.