一种基于自适应步长的载波相位恢复方法  

A Carrier Phase Recovery Method Based on Adaptive Step

作　　者：陈勇[1] 黄建国[1] 王芳[1] 

机构地区：[1]西北工业大学,西安710072

出　　处：《无线通信技术》2005年第3期14-16,21,共4页Wireless Communication Technology

摘　　要：近年来,为了实现无线通信中全数字化的载波同步,以文献[5]为代表,提出了一种依据最大似然估计理论,通过不断迭代计算最终实现载波相位同步的方法。本文针对该方法中步长固定的缺点,提出了一种基于自适应步长的载波相位恢复方法。由于步长能够自适应的变化,使得新算法的相位跟踪速度更快,适用于需要快速载波同步的相干通信系统。仿真结果表明,在高斯白噪声信道下,新方法的相位跟踪速度比固定步长方法大约提高一倍,此外,新方法能很好地解决收敛速度与稳态性能之间的矛盾,即使在较低的信噪比下仍有令人满意的相位跟踪效果。Recent years, a method of digital carrier synchronization is presented, which is based on the theory of maximum likelihood estimation and iterative calculation. In this paper, a novel carrier phase recovery method based on the adaptive step algorithm is introduced, corresponding to the disadvantage of the fixed step in the old method. Using this algorithm, the phase of the received signal can be tracked quickly because of the adaptive step. Therefore, it is suitable for those coherent communication systems which need fast synchronization. Simulation results show that, in the case of using the adaptive step the phase tracking speed of the new method is increased about 2 times in comparison with the constant step, even in a low SNR, a satisfied phase tracking result is obtained.

关 键 词：载波相位恢复 自适应步长 相干通信 

分 类 号：TN911.72[电子电信—通信与信息系统]