一种卫星信道下高效QOTDM传输方法  

Efficient QOTDM transmission method for the satellite channel

作　　者：段珍珍[1,2] 田斌[1,2] 易克初[1] 李运华[1,2] 

机构地区：[1]西安电子科技大学综合业务网理论及关键技术国家重点实验室,陕西西安710071 [2]西安电子科技大学信息感知技术协同创新中心,陕西西安710071

出　　处：《西安电子科技大学学报》2017年第1期176-181,共6页Journal of Xidian University

基　　金：国家自然科学基金资助项目(61571340);现代无线信息网络基础理论与技术"111"创新引智基地资助项目(B08038)

摘　　要：针对卫星移动信道的传输特性,提出了一种高效的准正交时分复用传输方式.在发送端,该传输方式采用高阶幅度相移键控调制,并进行多速率变换来消除样点交织后的频谱间隙,从而提高系统频谱效率;在接收端,构造循环卷积,并给出一种分块频域均衡算法.该均衡算法利用多径能量来抑制噪声干扰,同时也会消除匹配滤波时的样点间干扰.与传统的频域均衡算法相比,该均衡算法可以提高系统频谱利用率和数据传输效率.仿真结果表明:当误比特率为10-3时,与正交频分复用系统相比,该传输方式在时变莱斯衰落信道条件下可获得5dB左右的信噪比增益,且具有较强的抗多径衰落能力.An efficient Quasi-orthogonal time division multiplexing （QOTDM） transmission is proposed for the satellite mobile ehannels. High order modulation is used in this method to resist the nonlinear mobile satellite channel. The spectral gap of sample points is eliminated by multiple rate conversion at the transmitter in order to improve the speetral effieieney. At the receiver, cyclic is constructed by channel information and local PN sequence, and a frequeney domain equalization algorithm based on the block is presented. Theoretical analysis shows that this frequeney domain equalization method can use the energy of the multipath to suppress the noise and the interference between the forward and backward sample points can be eliminated in the meantime. Compared with the traditional frequency domain equalization based on the cyclic prefix, the speetral utilization and data transmission efficiency are improved. It is shown by the Monte Carlo simulation that the signal-to-noise ratio of 5 dB or so for the SER of 10-3 can be achieved by the scheme proposed compared with the OFDM in the time-varying Rieian channels.

关 键 词：准正交时分复用 正交频分复用 多速率变换 频域均衡 

分 类 号：TN927[电子电信—通信与信息系统]