Design of Robust LoS MIMO Systems with UCAs

Abstract

As millimeter wave wireless communications are expected to be widely deployed in future applications, line-of-sight multiple-input multiple-output (LoS MIMO) systems are likely to become more important. The performance of LoS MIMO systems relies heavily on the placement of the antennas at the transmit (Tx) and receive (Rx) arrays, where the optimal antenna placement depends on the distance between the arrays. However, as a LoS MIMO system may be required to operate over a range of distances, the variation of the capacity and the spatial multiplexing gain are key design factors. Considering uniform circular arrays (UCA), by assuming that more than one UCAs are available at the Rx, we propose three array selection schemes for robust design of LoS MIMO UCA systems over a range of distances between the arrays. Their performance is evaluated in terms of their practical implications and their robustness with regard to a suitably defined measure.