摘要
GPS(Global Positioning System)接收机中,常用的捕获方法有时域串行捕获方法、基于FFT(Fast Fourier Transform)的并行频率捕获方法和基于FFT的并行码相位捕获方法,但在某些应用场景下,会对卫星信号的捕获速度提出更高的要求,因此给出了一种基于相关的SFFT(Sparse Fast Fourier Transform)的卫星信号快速捕获算法。该算法结合卫星信号伪随机码的强自相关性的特性,将原有的SFFT的幅度估值去掉,利用时域串行的捕获方法,将SFFT算法中输出的大值坐标点对应的本地伪码与接收卫星信号做相关,进而捕获卫星信号。通过实验对算法进行验证,并与已有的卫星信号捕获方法进行对比,结果表明该方法能有效地运用于卫星信号捕获中,并且该算法的运算量要比传统捕获算法更低。
In GPS(Global Positioning System)receivers,commonly used acquisition methods are time-domain serial acquisition methods,FFT(Fast Fourier Transform)-based parallel frequency acquisition methods and FFT-based parallel code phase acquisition methods,but in certain application scenarios,it will put forward higher requirements on the acquisition speed of satellite signals,so a satellite signal fast acquisition algorithm based on correlated SFFT(Sparse Fast Fourier Transform)is given.This algorithm combined the strong autocorrelation characteristic of the satellite signal pseudo-random code,removed the original SFFT amplitude estimate,and used the time-domain serial capture method to convert the local pseudo-corresponding to the large-valued coordinate points output by the SFFT algorithm The code is correlated with the received satellite signal to capture the satellite signal.The algorithm is verified through experiments and compared with the existing satellite signal acquisition methods.The results show that the method can be effectively used in satellite signal acquisition,and the calculation amount of the algorithm is lower than the traditional acquisition algorithm.
作者
卢丹
李雅丽
Lu Dan;Li Yali(Tianjin Key Lab for Advanced Signal Processing,Civil Aviation University of China,Tianjin 300300,China)
出处
《信号处理》
CSCD
北大核心
2020年第8期1227-1233,共7页
Journal of Signal Processing
基金
国家自然科学基金项目(U1833112)
天津市自然科学基金(19JCQNJC01000)
中央高校基本科研业务费资助项目(3122017004)。
关键词
卫星信号
稀疏快速傅里叶变换
快速捕获
降采样
satellite signal
sparse fast Fourier transform
fast capture
downsampling
