Optimal uncoupled impedance matching for coupled MIMO arrays

It has recently been shown that a coupled impedance network is required to maximize the power received by a coupled array for arbitrary incident field. This paper explores the performance of uncoupled terminations under different incident field assumptions. The analysis shows that under certain impinging fields, an uncoupled load can be designed whose performance matches that of the optimal termination. However, as the incident field exhibits reduced directional bias, the performance of the optimized load tends to degrade. This observation suggests that one role of the termination is to effectively form a beam that is matched to the incident field structure.