Diversity Analysis on Transmit Antenna Selection for Spatial Multiplexing Systems With ML Detection

In this paper, we analyze the diversity order of the optimal transmit antenna selection (TAS) for spatial multiplexing (SM) systems with maximum-likelihood (ML) detection. By deriving the upper and lower bounds on the diversity order, we prove that the optimal TAS of selecting L antennas among M transmit antennas in the SM system with M transmit antennas and N receive antennas obtains a diversity order of N(M - L + 1), which coincides with the well-known results of the respective diversity orders MN and N for the special cases when L = 1 and L = M. Monte Carlo simulations confirm our theoretical result.