Abstract: A MIMO system which is used to achieve high data rate and capacity in transmission medium is one of the significant emerging technologies today. The interferences occurring between the different antenna elements in MIMO OFDM can be mitigated to improve the performance of the system. The precoding technique, where the data is coded and transmitted to reduce the bit error rate can be used for this. There are linear precoding and nonlinear precoding methods are there.Linear precoding schemes have low complexity and can achieve a reasonable capacity. The nonlinear precoding can access more capacity with much receiver complexity. In this paper, the BER performance of different precoding schemes like Channel Inversion, Block Diagonalization, DPC and TH precoding are analysed to get a better performance for the MIMO systems. Simulation results shows that the nonlinear precoding technique Dirty Paper Coding (DPC) achieves better performance than all other precoding methods.

Keywords: BER, DPC, MIMO, OFDM, Precoding.