Channel Orthogonalization (CO) and its Combination with THP (CO-THP) for Multiuser MIMO Systems

In this paper, a linear Channel Orthogonalization (CO) algorithm with low complexity is presented, which is applicable to systems with an arbitrary number of antennas and users. Unlike other conventional linear methods, CO obtains the orthonormal basis to achieve the precoding matrix by means of using Schmidt Orthogonalization method. Then, the algorithm (CO-THP) combining CO with Tomlinson-Harashima Precoding (THP) is proposed to eliminate the residual interference from any former user in CO. Different from the conventional THP algorithms, CO-THP eliminates all the Multi-User Interference (MUI) without amplifying the noise, which brings it better BER performance. And the combination with THP brings CO a higher capacity than linear scheme BD. Simulation results show the performance advantage obtained by the CO and CO-THP.