一种改进的QAM载波恢复方法  

A Modified Carrier Recovery Algorithm for QAM

作　　者：李小娟[1] 朱立东[1] 

机构地区：[1]电子科技大学通信抗干扰技术国家级重点实验室,四川成都610054

出　　处：《通信技术》2010年第3期47-48,193,共3页Communications Technology

基　　金：国家自然基金科学基金重大项目(批准号:60496310)

摘　　要：文中提出了一种新的QAM载波恢复环路结构。在此结构中频率检测和相位检测同时进行,在鉴相阶段引入了改进的加权直接判决(MWDD)算法。经仿真实验验证此方法提高了整个载波恢复环路的捕获速度,并使载波环路的相位抖动有所减小,16-QAM载波环路最大可以捕获11%符号率的频偏。A new structure of carrier recovery loop for QAM systems is proposed in this paper.In this structure,frequency detection and phase detection are carried out simultaneously.Meanwhile,a modified weighting decision-directed（MWDD）algorithm is adopted in phase detection period.Simulation indicates that the algorithm could improve the capture speed of carrier recovery loop and reduce the frequency flicker.The 16-QAM circuit could capture up to 11% frequency offset of the symbol rate.

关 键 词：QAM 载波恢复 频率检测 相位检测 MWDD算法 

分 类 号：TN92[电子电信—通信与信息系统]