On the Importance of Modeling the Mutual Coupling for Antenna Selection for Closely-Spaced Arrays

In this paper we consider a system in which multiple dipole antennas are placed side-by-side within a finite space at the receiver to form a uniform linear array, causing the dipole antennas to be closely spaced. We investigate the achievable rate with receive antenna selection and take into account both spatial correlation and mutual coupling effects between the antennas. We assume the full channel state information is available at the receiver but not at the transmitter. Opposite to what might be expected, the system achievable rate with receive antenna selection can outperform the system employing all the antennas, provided the number of antennas used is larger than a critical value. We also describe the optimal processing scheme which enumerates all possible antenna combinations and selects the combination maximizing the instantaneous achievable rate for a given channel realization.