Diversity-multiplexing tradeoff of MIMO systems with antenna selection

The diversity-multiplexing (D-M) gain tradeoff is a popular benchmark for measuring the performance of multi-input multi-output (MIMO) systems. This paper studies the fundamental D-M gain tradeoff of a pruned MIMO system where L-t transmit and L-r receive antennas are selected out of the full system with M-t transmit and M-r receive antennas (L-t <= M-t and L-r <= M-r). It is shown that a MIMO system with the optimal antenna selection (AS) has the same D-M tradeoff as the full system if the multiplexing gain is less than some threshold P, although it suffers from some diversity gain loss for the multiplexing gain larger than P. On the other hand, this paper quantifies, in terms of the D-M tradeoff, the gain of introducing additional transmit/receive antennas without increasing the number of RIP chains and coding complexity. We also propose a fast and D-M tradeoff-optimal AS algorithm as a byproduct of our analysis.