This paper introduces a theory for assessing and optimizing the multiple-input-multiple-output performance of multi-port cluster antennas in terms of efficiency, channel correlation, and power distribution. A method based on a convex optimization of feeding coefficients is extended with additional constraints allowing the user to control a ratio between the power radiated by the clusters. The formulation of the problem makes it possible to simultaneously optimize total efficiency and channel correlation with a fixed ratio between power radiated by the clusters, thus examining a trade-off between these parameters. It is shown that channel correlation, total efficiency, and allocation of radiated power are mutually conflicting parameters. The trade-offs are shown and discussed. The theory is demonstrated on a four-element antenna array and on a mobile terminal antenna.

翻译：本文提出了一种理论，用于从效率、信道相关性和功率分配角度评估和优化多端口集群天线的多输入多输出性能。基于馈电系数凸优化的方法被扩展，增加了额外约束条件，允许用户控制各集群辐射功率的比值。问题的公式化使得在保持集群辐射功率比值固定的同时，能够同时优化总效率和信道相关性，从而研究这些参数之间的权衡关系。结果表明，信道相关性、总效率和辐射功率分配是相互冲突的参数。本文展示并讨论了这些权衡关系。该理论通过一个四元天线阵列和移动终端天线进行了验证。