A New Approach to Semi-blind Channel Estimation for MIMO Wireless Communication System

A new approach to Semi-Blind Channel Estimation (SBCE) technique for Multiple Input Multiple Output (MIMO) wireless communication system is proposed. It combines the Least Square (LS) and Minimum Mean Square Error (MMSE) Training Based Channel Estimation (TBCE) scheme with whitening rotation based orthogonal pilot maximum likelihood (OPML) semi-blind channel estimation (SBCE) scheme. In the new approach the whitening matrix is obtained from blind data and rotation matrix is obtained from LS estimated channel. Another modification suggested in this contribution is the use of whitening matrix for MMSE estimate. The channel correlation matrix required for MMSE estimation can be obtained based on latest channel statistics and hence is more reliable. At high SNR this scheme offers better performance than the OPML SBCE method. These advantages are achieved at the cost of negligible reduction in performance in low SNR regime. General Terms Channel Estimation, MIMO, Wireless Communication.