摘要
随着卫星通信技术的不断发展,对低信噪比下的解调技术提出了越来越高的要求,尤其是针对机载平台下的卫星通信系统,需要在极低信噪比条件下进行解调。采用了一种基于载波相位内插的低信噪比解调算法,利用FFT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。仿真和结果表明,帧头长度为32时可以获得较好的解调性能,解调门限附近载波恢复导致的解调损失小于0.3 dB。
The development of satellite communication technology takes more and more requirements at low SNR （signal -noise ratio） demodulation technology,especially for airborne satellite communication system. In this paper,we analyze a low SNR demodulation algorithm based on carrier phase interpolation. Firstly the frequency offset estimation is performed by using FFT,and then the interpola- tion 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. Finally, the simulation results show that the algorithm has good demodulation performance when the frame header length is 32, and the demodulation loss caused by carrier recovery near demodulation threshold is less than 0.3 dB.R.
出处
《无线电通信技术》
2013年第2期39-42,共4页
Radio Communications Technology
