Block diagonalization for Multi-user MIMO Beamforming performance over Rician Channel

1 Professor, Department of Electrical and Electronics Engineering, Erciyes university, kayseri, turkey . 2 Department of Electrical and Electronics Engineering, Erciyes university, kaysers, turkey. ---------------------------------------------------------------------***--------------------------------------------------------------------Abstract In traditional wireless cellular networks, wireless mobile communication faces adversities due to noise and fading. At same cell, users can cause the co-channel interference (CCI) between each other. Thereby, CCI can deteriorate the downlink channel’s capacity. Depending on the multiple-input multiple-output (MIMO) system theory, wireless communication network systems researches have been important developments. MIMO system is used to overcome individual channel fading effect by employing spatial multiplexing. Exploiting the matrix of channel state information (CSI) can improve performance of wireless channel link. CCI which is created via additional users inside the cell borders can be limited by designing the beamforming precoding vectors for every user in Multi-User MIMO system (MU-MIMO). Linear precoder has number of methods; one of them is Block diagonalization (BD) method. This method using by beamforming precoding as a linear precoder in the MUMIMO broadcast channel system that transmits various information streams without interference to manifold users. This paper presents evaluation of the BD precoding performances in MU-MIMO beamforming over a Raylegh fading channel with CSI. Then, the channel matrix replaces the typical channel assumption with its correlated realistic Rician fading channel. Simulation results show that the Rician fading channel has performance improvement until with low Rician factor value, compared to a conventional channel. The high value of Rician factor can reduce the error rate.