多基站协作通信系统的频偏补偿策略

Carrier frequency ofset compensation algorithm for multi-base stations cooperative communication system

在多基站协作通信系统中,为了获得空间分集或复用增益,协作基站同时同频向多个终端发送数据,而终端同时同频收到多个具有不同频偏的信号.基站或终端不能通过预补偿或后补偿方法独立解决多基站多用户频偏补偿问题.针对这一难题,本文提出基于最大可容忍剩余频偏的收发联合补偿策略.仿真结果表明:该策略虽然不能完全消除多基站多用户频偏,但可将其控制在可容忍范围内.

In multi-base station cooperative communication systems, cooperative base stations （BSs） transmit to multiple user equipments （UEs） at the same time slots and carriers, in order to obtain spatial diversity or multiplexing gain. Therefore, a UE may receive several signals associated with different carrier frequency offsets （CFOs） simultaneously. It is impossible for BSs or UEs to pre- or post-compensate for the multiple CFOs respectively. We propose a joint pre- and post-compensation algorithm associated with relaxed residual CFOs. Simulation results show that the proposed algorithm is capable of substantially mitigating the CFOs of multi-base station cooperative systems though it cannot eliminate the multiple CFOs completely.