Capacity analysis of downlink MIMO-OFDMA frequency allocation with imperfect feedback information

Abstract

Opportunistic resource allocation in orthogonal frequency division multiple access (OFDMA) and multiple-input multiple-output (MIMO) techniques are among the key methods to enhance the spectral efficiency in future wireless communication networks. In this paper, we express information theoretical capacity results for MIMO-OFDMA systems with optimal rate adaptation. So called best-M feedback is used for OFDMA resource allocation. Transmit antenna selection (AS) and space-time block coding (STBC) schemes are analyzed. We investigate the effect of the imperfect feedback to the system capacity. The results indicate the proposed sub-block best-M (SBB-M) feedback strategy with AS provides promising tradeoff between the system capacity, feedback overhead and robustness against feedback bit errors.