A joint optimized scheme of transceiver precoding matrix based on interference alignment for multi-cell MIMO systems

In downlink multi-cell multiple input multiple output (MIMO) systems, the inter-cell interference has become the main factor to restrict the system capacity. This paper proposes a joint optimized scheme of transceiver precoding matrices based on interference alignment technology to mitigate inter-cell interference. At the transmitter, via the singular value decomposition of target channels, the scheme selects the precoding vectors which are matched with the best characteristic sub-channel to transmit the signal and enhances the signal strength. At the receiver, the scheme selects the vectors of the most matching target received signal from the null space of interference to form the receiver matrix based on the zero-forcing (ZF) criterion, which further improves the target signal strength. The simulation results show that the proposed scheme has improved the system capacity compared with the existing precoding matrix design method.