摘要
高动态给载波的跟踪带来了很大的困难,本文研究采用锁频环(FLL)和锁相环(PLL)相结合的方法来实现载波跟踪。对常用的叉积自动频率跟踪环(CPAFC)提出了改进,改进后的鉴频算法具有更宽的鉴频范围和更小的估计误差。通过MATLAB对整体环路进行了仿真,结果表明该环路可实现在低信噪比、多普勒频移为±300 kHz、频率一次变化率为30 kHz/s下实现载波的跟踪。
Under the circumstances of high dynamic, it is difficult to achieve carrier tracking. The configuration of carrier tracking, which combining FLL with PLL, is presented in this paper. A improved CPAFC frequency control arithmetic is discussed in this paper. The range of the improved method is larger then CPAFC, and the error is less. At the same time, the loops is simulated by MATLAB and the simulation results show that the loops can track the signal one the conditions that the low SNR, the Dopper frequency varies at the speed of 30 kHz per second and the Doppler frequency shift varies from -300 kHz to ＋300 kHz.
出处
《电子测量技术》
2009年第3期25-27,共3页
Electronic Measurement Technology
关键词
高动态
载波跟踪
AFC
high dynamic
carrier tracking
AFC
