Design of Linear Precoder to Maximize Sum Rate Capacity

Particle Swarm Optimization algorithm (PSO) is used in the optimization of Multi user Multi Input and Multi Output (MU-MIMO) communication systems. Linear precoding is employed in MU-MIMO communication system to improve the system capacity and to minimize the receiver complexity. The previous works on optimization algorithm to design a linear precoder to maximize the system capacity is assumed to have perfect channel state information (CSI) at the base station (BS) and antenna size 4x4. However the CSI available at the BS is imperfect due to channel estimation errors. Hence, in this paper, the precoder is designed to maximize system capacity by considering the channel estimation error. Further, the PSO algorithm is used to find the precoding matrix and also analyze the performance of capacity and bit error rate with different variance values and with different antenna sizes. The simulation results show that the system capacity performance of the proposed precoder which considers channel estimation error outperforms the previously proposed precoder.