一种新的CPM信号载波同步算法  

A Novel Carrier Synchronization Algorithm for CPM Signals

作　　者：韩立峰[1] 尚耀波[1] 张东伟[1] 

机构地区：[1]空军工程大学空管领航学院,西安710051

出　　处：《空军工程大学学报（自然科学版）》2018年第1期48-53,共6页Journal of Air Force Engineering University(Natural Science Edition)

基　　金：国家自然科学基金(61472443;61703427)

摘　　要：针对连续相位调制(CPM)信号载波同步中存在的估计精度低、信噪比适应能力弱以及计算复杂度高等问题,提出了一种基于数据辅助的CPM信号载波同步算法。首先分析建立了预编码CPM调制同步系统的数学模型,并据此推导了信号相位估计值的对数似然函数;然后利用后验概率均值实现对载波同步参数的精确估计,同时对算法的相偏估计精度和频偏估计范围进行了理论分析;最后利用蒙特卡罗仿真实验验证了所提算法的有效性。理论分析和仿真结果表明:新算法对CPM信号载波同步精度高,信噪比适应能力强,且能够适用于大频偏环境,同时在计算量上相比EM算法具有一定优势。Aimed at the problems that the performance is poor, the adaptability of SNR is weak, and the high computation is complex in the carrier synchronization for the CPM signal, a novel carrier synchronization algorithm based on the code assist is proposed in this paper. Firstly, a synchronization system model with CPM modulated signals is established, and in view of the above the log likelihood function of the carrier phase is deduced. Then, the parameter estimation and carrier synchronization are realized through utilizing the mean value of the posterior probability. And the estimation precision and the estimation range of phase offset are analyzed in theory. Finally, the effectiveness of the proposed algorithm is verified by the Monte-Carlo simulation. The theory analysis and simulation results show that the new algorithm is good in performance in carrier synchronization of CPM signals and the adaptability of SNR, and suitable for the circumstances of large frequency offset or phase offset. Simultaneously, the algorithm is superior to the EM algorithm in the computational complexity.

关 键 词：连续相位调制 载波同步 判决反馈 预编码 

分 类 号：TN911.3[电子电信—通信与信息系统]