Spatial multiuser access OFDM with antenna diversity and power control

The capacity can be dramatically increased by employing multiple antennas. However, in the multiple-user environment, the system performance is limited by cochannel interference. This paper describes a spatial multiuser access scheme using singular value decomposition (MU-SVD), associated with orthogonal frequency division multiplexing (OFDM) for an intersymbol interference channel. The proposed method can separate the transmission of interest in the space domain, without loss of antenna diversity, thus successfully isolating each source with a spatially distinct signature waveform. Moreover, power control for sub-channels is adopted to enhance the spectral and power efficiency. Simulations show MU-SVD with power allocation achieves a huge gain.