Although there have been extensive studies on transmit beamforming in multi-input single-output (MISO) multicell networks, achieving optimal sum-rate with limited channel state information (CSI) is still a challenge even with a single user per cell. A novel cooperative downlink multicell MISO beamforming scheme is proposed with highly limited information exchange among the base stations (BSs) to maximize the sum-rate. In the proposed scheme, each BS can design its beamforming vector with only local CSI based on limited information exchange on CSI. Unlike previous studies, the proposed beamforming design is non-iterative and does not require any vector or matrix feedback but requires only quantized scalar information. The proposed scheme closely achieves the optimal sum-rate bound in almost all signal-to-noise ratio regime based on non-iterative optimization with lower amount of information exchange than existing schemes, which is justified by numerical simulations.
翻译:虽然对多投入单产出(MISO)多细胞网络中的传输光束进行了广泛的研究,但即使每个细胞有一个单一用户,仍难以在有限的频道状态信息(CSI)中实现最佳总和率。提出了一个新的合作下行链接多细胞MISO波束成型计划,各基站之间的信息交流非常有限,以最大限度地实现总和。在拟议的计划中,每个BS都可以根据有关CSI的有限信息交流来设计其波束成型矢量,只有局部的CSI。与以往的研究不同,拟议的波束成型设计是非全称性的,不需要任何矢量或矩阵反馈,而只需要量化的标度信息。拟议的计划在几乎所有信号对噪音比率制度中都实现了最佳总和率约束,其基础是非热优化,其信息交流量比现有计划要低,而数字模拟是有理由的。