为提高北斗导航接收机在高动态下的载波跟踪性能,对载波跟踪环的各个模块和逻辑参数进行了研究。利用变环路带宽技术,提出了一种环路参数可调的载波跟踪环。通过对FLL(锁频环)和PLL(锁相环)的具体分析,设计并实现了一种基于现场可编程门阵列(FPGA)和高性能数字信号处理器(DSP)的载波环路跟踪方案,在DSP端进行环路控制,在FP-GA端完成载波的剥离。测试结果表明,该方案能实现高动态下载波信号的快速精确跟踪,具有良好的实时性和推广价值。
To improve carrier tracking performance of the BD receiver in a high dynamic environment, the logical parameters of carrier loop are analyzed. Based on the analysis of the FLL and PLL, using variable loop bandwidth technology, a parameter ad- justable carrier tracking loop is proposed. Through the analysis of the FLL and PLL, a new solution of carrier tracking loop based on DSP and FPGA is designed and implemented. DSP is used to realize the loop control while the demodulation of the carrier wave is realized in FPGA. Simulation results show that the design can achieve BD carrier's accurate tracking in high dynamic en- vironment, which has relatively strong popularization using value.