GPS软件基带信号处理与定位实现

在GPS软件接收机架构下,基于计算机MATLAB软件平台,利用实际采集的GPS中频信号,在普通计算机上实现了一个硬件接收机的所有基带信号处理以及导航解算功能：详细介绍了FFT相关捕获方法,经典载波、伪码跟踪环设计;对于接收机中最重要的伪距计算环节,给出一种完全不需要本地时间,而仅利用采样数据,根据由捕获和跟踪得到的观测量,提取出各卫星帧头到达天线的时延差,从而计算伪距的方法,最终实现了定位解算。实验结果表明,利用真实GPS中频数据,可以在GPS软件接收机架构下,完成全部基带信号处理以及定位解算等完整过程,完全实现一个接收机功能,并适合精密单点定位、多模接收机等算法开发。

GPS Baseband Signal Processing and Positioning Realization Based on Software Receiver

A software GPS receiver was developed using real GPS intermediate frequency samples based on MATLAB software on personal computer. All baseband signal processing procedures were carefully investigated including FFT acquisition method,classical carrier and pseudo-code tracking loop design. A method was introduced to calculate pseudo-range without local time. The method calculated the pseudo-range in a relative way using the arriving time difference of each satellite signal based on the sampling frequency information and finally user position were calculated. Simulation results show that software GPS receiver could realize all functions of a common GPS receiver and provide opening structure and feasibility for new algorithm development such as precise positioning and multi-model receiver algorithms.