Research On Precoding Technique In MIMO System

Modern wireless communication systems require higher data transmission rate and spectrum utilization than ever. That promotes the research and the application of the new and sophisticated signal processing methods. MIMO system precoding technique, which has become one of the research focuses, uses some kinds of channel state information to match the transmit signal with the wireless channel, in order to defeat channel fading and improve the BER performance and spectral efficiency. At present, precoding has been included in IEEE802.16e. And it is also the key technology of wireless communication regardless of the current or future. The researches of MIMO precoding mainly concern precoding criterions, limited feedback techniques, codebook design methods, and so on.Besed on the efforts of others, we propose an improved beamforming method of MIMO relay system. This algorithm gets the estimated value of the CSI from the receiver through mean feedback channel model, and finally gave the optimal beamforming solution.