Galileo/GPS卫星导航模拟源的FPGA算法设计与实现

Galileo卫星导航系统各频段信号中引入了多种新兴调制方式,是新一代卫星导航系统典型代表。目前可见星数量有限,给深入探索带来了一些困难,故采用“上位机+FPGA+DSP”架构设计实现了Galileo+GPS卫星导航信号模拟源,着重研究卫星导航模拟源FPGA端的算法,完成了多普勒频移模拟、副载波生成、偏置载波调制、伪距信号生成的工作,解决了各模块信号对齐的关键技术,产生了Galileo E1 OS和GPS L1 C/A中频信号。利用硬件接收机对生成的信号进行接收验证,实验结果表明,接收机能正确捕获跟踪定位,定位坐标与预设坐标相符,证明了仿真信号的正确性。

Design and implementation of FPGA algorithm for Galileo/GPS satellite navigation signal simulator

Various new modulation modes have been introduced into the signals with different frequency bands of Galileo satellite navigation system, which is a typical representative of the new generation satellite navigation system. The limited number of visible Galileo satellites has brought some difficulties to further exploration. In this paper, a Galileo+GPS satellite navigation signal simulator is designed and implemented based on the architecture of "PC+FPGA+DSP". The algorithm of FPGA in satellite navigation signal simulator is mainly studied, doppler frequency shift simulation, subcarrier generation, offset carrier modulation and pseudo range signal generation are completed, key technology of signal alignment of all modules is solved,and the intermediate frequency signals of Galileo E1 OS and GPS L1 C/A are generated. The hardware receiver is used to receive and verify the generated signal, the results of experiments show that the receiver can correctly capture, track and fix positions, and the location coordinates are consistent with the preset coordinates, which prove the correctness of the simulation signal.