An investigation of self-interference reduction strategy in correlated SM-OFDMA systems

One of the efficient ways to transmit high data rate in a wireless network is by employing a multiple antenna transmission scheme, known as the multiple-input multiple-output (MIMO). One of the MIMO schemes, known as Spatial Multiplexing (SM) relies on the linear independence data streams from different transmit antennas to exploit the channel capacity. Consequently, SM suffers considerably from the effect of spatial correlation, also known as self-interference in the literature, thus become one of the limiting factor in achieving the capacity benefit that SM offers. In an attempt to increase the robustness of the SM transmission for deployment in wide range of correlated channels, the use of dynamic subcarrier allocation (DSA) in a downlink Orthogonal Frequency Division Multiple Access (OFDMA) system is investigated. The Effective Signal-to-Interference-and-Noise Ratio (ESINR) metric is used as the performance metric to determine the subcarrier quality. The ESINR metric can be utilised for the subcarrier allocation process in order to exploit the multiuser diversity gain that can be offered in a correlated SM-OFDMA downlink system.