摘要
机载平台下的小站型卫星通信系统,通常需要在低信噪比条件下进行解调;因此,如何完成低信噪比条件下的载波恢复成为解调中的一个关键问题。分析了一种基于相位内插的低信噪比载波恢复算法,此算法利用FFT算法进行频偏估计,然后利用相邻2个帧头的相位估计结果进行内插,得到帧内各符号的载波相位信息,实现载波恢复,并对不同帧头长度比例下的帧头选取和载波恢复算法的性能进行了仿真分析,结果表明此算法能够很好地完成低信噪比下的载波恢复功能。
For airborne platform station in satellite communication system,the demodulation usually needs to be done under the condition of low SNR.Therefore,how to perform carrier recovery under the condition of low SNR becomes a key problem in the demodu- lation.This paper analyzes a low SNR demodulation algorithm based on carrier phase interpolation.Firstly the frequency offset estimation is performed by using FFT,and then the interpolation is realized by using the phase estimation results of two adjacent frame headers to obtain the carrier phase information of various symbols in frame and realize carrier recovery. The performance with different header lengths as well as the selection of the length is analyzed. Finally, the performance of the carrier recovery algorithm is analyzed in the simulation.The simulation results show that the algorithm has good performance in carrier recovery under the low SNR.
出处
《无线电通信技术》
2015年第4期40-42,46,共4页
Radio Communications Technology
基金
国家部委基金资助项目
