Transmit Antenna Selection in MIMO-OFDM Systems: Bulk Versus Per-Tone Selection

This paper provides an exact diversity gain analysis for transmit antenna selection in MIMO-OFDM systems with linear receivers, a topic scarcely addressed in prior literature. In a frequency-selective fading (as opposed to a frequency-flat fading) channel one of either two methods of antenna selection may be applied. We name these methods bulk selection and per-tone selection. From an implementation perspective each method presents a different complexity-performance tradeoff. Through rigorous mathematical derivation, we demonstrate that both methods realize the same diversity order. Moreover, the coding gain realized by the two selection methods is also analyzed and compared through simulation. Overall, this paper confirms the advantage of antenna selection technology in MIMO-OFDM systems, and provides comprehensive guidelines for antenna selection strategies in realistic scenarios, from both the performance and complexity perspectives.