基于判决反馈环的数字化载波恢复方法

Digital Carrier Recovery Method Based on Decision-Feedback Loop

针对常见的非面向判决环在载波恢复过程中对锁相环路噪声的抑制效果不佳的问题,提出一种基于判决反馈环的设计并在FPGA上实现,使用MODELSIM和MATLAB对载波恢复的结果进行联合仿真测试。仿真结果表明,设计的判决反馈环可以实时、准确地完成载波恢复,且与非面向判决的平方环和科斯塔斯环相比,在相同输入信号和环路参数设置的条件下,大幅降低因加性噪声引起的跟踪抖动,在通用数字通信系统的载波恢复中具有普适性。

Aiming at the problem of poor suppression of PLL noise in the carrier recovery process utilized common Non-oriented Decision loop,a design based on decision feedback loop is proposed and implemented on FPGA,MODELSIM and MATLAB are used to perform integrated simulation test for the results of carrier recovery. The simulation results show that,the decision-feedback loop designed can accurately complete carrier recovery in real time. By Comparing with the non-decision-oriented square loop and Costas loop,it significantly reduces the tacking jitter caused by the additive noise under the condition of the same input signal and loop parameter settings,and it is universal in the carrier recovery of the general digital communication systems.