Transmit and Receive Antenna Pairing in MIMO Relay Networks

In this paper we consider the problem of antenna selection and pairing in a MIMO relay network when block diagonalization is used at the source with ZF combining at the destination. We start with relay selection where it is assumed that all receive and transmit antennas of a selected relay are used for transmission and argue that antenna selection is superior to relay selection. We propose two algorithms for joint receive and transmit antenna selection and pairing which we refer to as `optimal pairing´ and `greedy pairing´. Simulation results show that optimal pairing scheme outperforms the existing antenna selection scheme and that greedy pairing gives nearly the same performance as optimal pairing.