A Throughput Enhancing Linear Precoding Scheme for the MIMO Downlink

A novel linear precoding scheme is proposed for the downlink of multiuser multiple input multiple output (MIMO) systems, that offers enhanced data throughput compared to conventional precoding. The proposed technique is based on the fact that part of the instantaneous multiple access interference (MAI) inherent in a multiuser MIMO system adds constructively to the useful signal. It utilises this concept by applying partial linear precoding such that the destructive part is eliminated while the constructive part of MAI is preserved and exploited. By doing so, the effective signal to interference-plus-noise ratio (SINR) delivered to the mobile unit (MU) receivers is enhanced, without the need to invest in additional transmitted signal power at the MIMO base station (BS). The presented analysis and simulations verify that the proposed precoding scheme significantly enhances the data throughput compared to conventional precoding.