Power Allocation Strategy for Compact MIMO Transmitters with Uniform Circular Arrays under the Influence of Antenna Mutual Coupling

This paper is concerned with the optimal transmission/power allocation scheme for a MIMO system employing a uniform circular array (UCA) antenna at the transmitter and a uniform linear array (ULA) antenna at the receiver. Investigations include mutual coupling (MC) effects in the UCA. By applying the transmitting mutual impedances, closed-form expressions for the spatial fading correlation (SFC) function of the UCA are derived. Using SFC that takes into account mutual coupling effects, an optimal power allocation scheme at the transmitter is developed. Numerical simulations illustrate the proposed transmission scheme gains extra capacity.