基于FPGA的64QAM解调系统算法研究  

Research into The Algorithm of 64QAM Demodulation System Based on FPGA

作　　者：殷志勇 YIN Zhi yong(The 723 Institute of CSIC,Yangzhou 225101,China)

机构地区：[1]中国船舶重工集团公司第七二三研究所,江苏扬州225101

出　　处：《舰船电子对抗》2018年第2期98-103,共6页Shipboard Electronic Countermeasure

摘　　要：针对64正交振幅调制(QAM)数字通信系统,研究了常用的载波恢复算法:直接判决(DD)算法、极性判决算法,提出了QAM系统解调方法:初始零门限的极性判决算法+DD算法。该算法更适合于高阶QAM载波相位的快速锁定。位同步模块为载波恢复提供定时信号,采用稍微改进的Gardner定时误差检测算法实现环路的反馈调节,并给出Matlab仿真,验证了算法的可行性。以Matlab和Vivado为软件开发平台,设计载波恢复、定时同步的具体现场可编程门阵列(FPGA)实现电路,经测试证明该模块能快速、较精确地实现解调。In view of 64 quadrature ampltitude modulation（QAM）digital communication system,this paper studies common carrier recovery algorithms：decision directed（DD）algorithm and polarity decision algorithm,and proposes the demodulation method of QAM system：the initial zero threshold polarity decision algorithm and DD algorithm.This algorithm is more suitable for fast locking of high order QAM carrier phase.The bit synchronization module provides the timing signal for carrier recovery,and a slightly improved Gardner timing error detection algorithm is adopted to realize the feedback adjustment of the loop,and Matlab simulation is given to verify the feasibility of the algorithm.Matlab and Vivado are taken as the software development platform,the specific field programmble gate array（FPGA）implementation circuit of carrier recovery and timing synchronization is designed.It is proved that the module can realize the demodulation fast and accurately through the test.

关 键 词：正交振幅调制 载波恢复算法 位同步 现场可编程门阵列 

分 类 号：TN919.3[电子电信—通信与信息系统]