基于DSP+FPGA的高动态GPS信号载波环路设计

为了提高动态环境下捕获、跟踪GPS信号的环路性能,通过分析环路逻辑时序、参数和高动态下多普勒频移的变化特性,使用高阶、宽带宽的跟踪环路,设计了一种基于DSP+FPGA的载波捕获、跟踪方法。利用现场可编程门阵列(FPGA)对信号进行傅里叶变换,实现载波的快速初捕和二次精捕,同时利用数字信号处理器(DSP)实现具有自动调整功能的二阶频率锁定环路的辅助三阶Costas-PLL载波跟踪环,使得环路具有抗高动态性能的同时仍拥有较高的跟踪精度。仿真实验表明:该方案能实现高动态下载波信号的快速捕获与精确跟踪。

Carrier Loop Design for High-dynamic GPS Signal Based on DSP+FPGA

In order to improve GPS signal's acquisition,tracking performance in a high dynamic environment,the sequential logic,loop parameters and high dynamic changes under the Doppler frequency shift are analysed.The wide bandwidth and high-order tracking loop is used.A loop to carrier acquisition and tracking is designed based on DSP+FPGA.By signal's Fourier transform,field programmable gate array(FPGA) is used to complete fast carrier first capture and second precise acquisition,while digital signal processor(DSP...