Transmit phase control to increase the minimum eigenvalue of channel correlation matrix in the E-SDM/OFDM system

In multiple-input multiple-output (MIMO) systems, the eigen-beam space division multiplexing (E-SDM) system has been proposed for mitigating the effect of co-channel interference (CCI). Received signal to noise ratio (SNR) in the E-SDM system depends on the eigenvalues of the channel correlation matrix. Consequently, the bit error rate (BER) performance of the data stream multiplied by the minimum eigenvalue is degraded in comparison with that of another data stream. We propose an E-SDM/OFDM system to control the eigenvalues of a channel correlation matrix by using transmit phase control. Computer simulation results indicate the proposed E-SDM/OFDM system with transmit phase control can improve the BER performance compared with E-SDM/OFDM system without using transmit phase control.