An Effective MAP Channel Estimation for MIMO-OFDM Systems
一种有效的MIMO-OFDM系统MAP信道估计

For Multiple-Input Multiple-Output with Orthogonal Frequency Division Multiplexing (MIMO-OFDM) systems, Maximum A posteriori Probability (MAP) channel estimation algorithm uses expectation maximum (EM) algorithm to reduce complexity, but it will lead to error floor phenomenon. The data transmission efficiency of systems is subject to the number of transmit antennas. According to these problems, in this paper, an effective MAP algorithm is proposed and its performance is analyzed. The proposed algorithm lowers the estimated error depending on the spatial independence of MIMO channels in angle domain on the basis of making use of EM algorithm to decrease the complexity. To improve the data transmission efficiency and the performance of estimation, joint estimation is carried out over multiple OFDM symbols. Simulation results indicate the proposed algorithm obtains better estimated performance and higher data transmission efficiency.