Limited feedback design in MIMO-OFDMA system using zero-forcing beamforming

In this paper, we consider amount of feedback and resource allocation for a downlink in MIMO-OFDMA system. The amount of feedback data increases with the number of user, subcarrier, antenna numbers rise. In order to limit the feedback date in a fix level, a prefixed threshold based feedback is proposed. The value of CSNR is feedbacked only when the channel gain is greater than the threshold. Simulation results show that the whole program can significantly reduce the feedback date and the computational complexity while obtaining the better system capacity.