Performance of transmit antenna selection in space-time coded OFDM systems

In this paper, we investigate the asymptotic performance of per-tone, bulk, and joint bulk/per-tone transmit antenna selections in orthogonal frequency-division multiplexing systems employing orthogonal space-time block coding (OSTBC). In particular, we show that the diversity and coding gains of all three systems are identical. This is a remarkable result since it demonstrates that systems with M transmit antennas operating in the high signal-to-noise ratio regime can achieve optimal performance while only employing enough radio frequency circuitry to convey OSTBC over L < M antennas on all subcarriers, thus offering significant savings over conventional approaches.