利用均匀线阵实现高移动性通信系统中的多普勒补偿

Doppler Compensation for High-Mobility Communication Systems Using Uniform Linear Array

为了消除高移动性正交频分复用系统中多普勒扩展引发的子载波间干扰，提出一种利用均匀线阵同时补偿多个多普勒频率的方法．该方法首先从空域的角度区分开具有不同多普勒频率的入射径，形成多个子信道，再分别对各个子信道进行多普勒补偿，最后对补偿后的子信道最大比合并，实现多普勒分集增益．子信道的时变性在多昔勒补偿后变低，因此可以避免较为复杂的信道估计和均衡算法．仿真结果表明，在阵列孔径足够的情况下，该方法能有效对抗正交频分复用系统在高移动性环境下的误码率平台效应，较单天线接收方法有6～8dB的信干比增益．

A scheme which employs umtorm linear array anu can compensate multiple Doppler shifts simultaneously is proposed to eliminate interearrier interference caused hy Doppler spreading in high-mobility orthogonal frequency division multiplexing systems. The scheme separates different paths with unique Doppler frequency in space-domain, and generates multiple subchan nels. The Doppler shift on each sub-channel is then corrected independently and finally, the com- pensated multiple sub-channels are combined together for maximal-ratio so that Doppler diversity gains are realized. The time-variance of each sub-channel is reduced after compensation, and the estimation and equalization processes on receivers are simplified. Simulation results show that when sufficient elements are used, the error floors in high-mobility scenario are effectively com- bated, and a 6-8 dE signal-to-interference gain over one-antenna reception is obtained by the proposed scheme.