Transmit Beamforming Interpolation Algorithm for MIMO-OFDM Systems in the Limited Feedback Scenario

In the limited feedback scenario, optimal beam forming requires channel state information (CSI) in the form of the beam forming vectors for each OFDM sub carrier, the beam forming vectors are quantized at the receiver and then the quantized information is provided to the transmitter. In order to decrease the feedback overhead caused by the beam forming on every sub carrier in multiple-input multiple-output orthogonal frequency division multiplexing (M IMO-OFDM ) systems, the beam forming issue is investigated for the MIMO-OFDM system, where the channel state information on certain sub carriers at the transmitter as well as the feature of the channel correlation in frequency band are fully exploited. By employing some interpolation methods among many beam formers at different carriers, This paper proposes a linear and Gaussian interpolation algorithms for MIMO-OFDM systems with limited feedback, The simulation results show that the new algorithms acquire proper gain in performance, indicating that the proposed schemes improved the system performances greatly.