激光技术, 2016, 40 (2): 264, 网络出版: 2016-03-29
一种基于星间光链路的帧同步与频偏估计方法
A approach of frame synchronization and frequency offset estimation based on optical satellite link
光通信 帧同步 差分相关算法 载波频偏估计 多普勒效应 optical communication frame synchronization difference correlation algorithm carrier frequency offset estimation Doppler effect
摘要
为了解决星间激光通信不同步导致的信息质量差与解调难度大等问题, 针对滑动互相关算法帧同步易受载波频偏影响的不足, 采用计算仿真的方法分析了星间多普勒效应引起的载波频偏程度, 提出差分相关算法以实现帧同步与载波频偏估计, 并给出硬件实现方案, 分析了差分相关算法的帧同步与载波频偏估计性能。结果表明, 差分相关算法能够实现大载波频偏影响下的帧同步, 且具有较强的频偏估计性能, 采用差分相关算法后系统的误码性能提升近3dB。此结果说明, 差分相关算法是解决星间激光链路同步问题的有效方法。
Abstract
The unsynchronization of optical satellite communication leads to error information and demodulation difficulty. And carrier frequency offset has effect on frame synchronization of sliding correlation algorithm. To solve the problem, frequency offset caused by satellite Doppler effects was analyzed by calculation simulation and difference relation algorithm was proposed for the realization of frame synchronization and frequency offset estimation. Implementation scheme of hardware was given. The performance of difference relation algorithm was analyzed. The results show that difference relation algorithm implements frame synchronization under the influence of high carrier frequency offset and has strong ability of frequency offset estimation. After using difference correlation algorithm, the error bit performance of the system increases nearly 3dB. It is useful to use difference relation algorithm to solve the synchronization problem of laser satellite link.
邓博于, 赵尚弘, 李勇军, 程振, 张曦文. 一种基于星间光链路的帧同步与频偏估计方法[J]. 激光技术, 2016, 40(2): 264. DENG Boyu, ZHAO Shanghong, LI Yongjun, CHEN Zhen, ZHANG Xiwen. A approach of frame synchronization and frequency offset estimation based on optical satellite link[J]. Laser Technology, 2016, 40(2): 264.