面向低轨卫星通信的OTSM时频同步算法  

OTSM Time-Frequency Synchronization Algorithm for LEO Satellite Communications

作　　者：于洪轩 崔高峰[1,2] 王卫东 郭世龙[1,2] YU Hongxuan;CUI Gaofeng;WANG Weidong;GUO Shilong(School of Electronic Engineering,Beijing University of Posts and Telecommunications,Beijing 100876,China;Key Laboratory of Universal Wireless Communications,Ministry of Education,Beijing University of Posts and Telecommunications,Beijing 100876,China)

机构地区：[1]北京邮电大学电子工程学院,北京100876 [2]北京邮电大学泛网无线通信教育部重点实验室,北京100876

出　　处：《北京邮电大学学报》2024年第6期99-104,共6页Journal of Beijing University of Posts and Telecommunications

基　　金：国家自然科学基金项目(62171052)。

摘　　要：为了应对低轨卫星通信网络中复杂的信道环境,消除时间偏移以及载波频率偏移带来的干扰,提出了一种面向正交时间序列复用(OTSM)调制技术的时频同步算法。基于二维搜索的时间同步算法利用导频信号在时延-时间域上的周期性,在时延和时间维度上搜索导频序列,估计接收信号的时间偏移。基于二维相关函数的频率同步算法对导频序列的二维相关函数值求相位,估计接收信号的载波频率偏移。仿真实验结果表明,所提算法在星地场景下具有良好的误码率性能。In order to cope with the complex channel environment in low earth orbit satellite communication networks and eliminate the interference caused by time offset and carrier frequency offset,a time-frequency synchronization algorithm oriented to orthogonal time sequence multiplexing(OTSM)modulation technology is proposed.The time synchronization algorithm based on two-dimensional search uses the periodicity of the pilot signal in the delay-time domain to search pilot sequence in the delay and time dimensions to estimate the time offset of the received signal.The frequency synchronization algorithm based on the two-dimensional correlation function estimates the carrier frequency offset of the received signal by calculating the phase of the two-dimensional correlation function value of the pilot sequence.The simulation results show that the proposed time-frequency synchronization algorithm has good bit error rate performance in the satellite-ground scenario.

关 键 词：低轨卫星 正交时间序列复用 时间同步 频率同步 相关函数 

分 类 号：TN927.2[电子电信—通信与信息系统]