A SINR Estimation Method For MIMO-OFDM System

The recent research on information theory indicated that, MIMO technology can increase the capacity of wireless communication remarkably, and OFDM technology, which has the advantages such as high spectrum utilization and multipath fading, is a kind of multicarrier high speed transmission technology. MIMO and OFDM are the key technology applied to the fourth generation mobile communication system. However, a variety of communication technologies has its own application environment and conditions. In wireless communication, environment and conditions of communication refers to the conditions and quality of wireless channel. The purpose of this paper is to explore a way to accurately measure channel quality in real-time, to provide a channel quality parameter for adaptive modulation, mode switching and power control in MIMO-OFDM system.Based on the analysis of the definition of SINR, its physical meaning and characteristics, we believe that SINR is an important characterization parameter, which can predict BER performance of the received signal and reflect the channel quality. Then, we focus on analysis of the correlation of MIMO channel and the condition number of MIMO channel. The condition number of MIMO channel will amplify the effect of noise, thus affecting the performance of detection. The article also analyze the received MIMO signals'Euclidean distance after the signal Aliased and merged, this Euclidean distance determines the performance of ML detection and the ability of signal to Noise tolerance. And, the condition of MIMO channel larger, Euclidean distance after the signal Aliased and merged smaller. Based on this analysis, this paper proposed three single-carrier MIMO-SINR estimation methods, respectively to vertical encoding, horizontal encoding and Alamouti encoding. An abstract method, which is called RBIR, is the theory we will use to abstract a single carrier-class estimated SINR to the link level estimated SINR. Finally, Based on WIMAX uplink virtual MIMO, this paper provided an estimated simulation programs and test programs, and simulation results. Simulation results show that the program proposed in this paper is easy to implement and meet the needs of practical applications.