蜂窝间干扰是无线蜂窝网络中一个重要的性能瓶颈, 基站协同可以消除小区边缘用户受到的严重的蜂窝间干扰, 提高蜂窝系统的性能和频谱效率. 针对下行链路基站协同通信系统, 提出一种信道衰落补偿功率分配方法, 以及内部联合分布式空时编码(inner joint distributed space-time coding, IN-J-DSTC) 基站协同传输方案, 以抑制蜂窝边缘用户受到的严重的蜂窝间干扰. 仿真结果表明, 该方法可以根据信道状况, 在源基站及协同基站间自适应地分配信号发送功率, 同时明显消除蜂窝边缘用户所受到的蜂窝间干扰, 从而显著地提高系统的误码率性能.
Capacity of a cellular system on the downlink is significantly limited by inter-cell interference (ICI), especially at the cell boundary. Multi-cell joint processing can mitigate ICI and thereby greatly improve performance and spectral efficiency of cellular systems. This paper considers a cellular system with base
station (BS) cooperation on the downlinkand propose an adaptive power allocation scheme to compensate the channel fading effect. Further, a BS cooperation transmission method is proposed to remove ICI experienced by cell boundary users. The method is inner joint distributed space-time coding (IN-J-DSTC) BS cooperation transmission with pre-coding. Simulation results show that the bit error rate (BER) performance can be significantly improved by effectively suppressing ICI with the proposed BS cooperation schemes and by allocating transmit power adaptively between the source and the cooperative BS according to the channels between them and the destination.
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