Improved Subspace-Based (Semi-) Blind Channel Estimation for Block Space-Time OFDM

Multiantenna wireless systems have been well studied in achieving high data rates. In this paper, we improve a subspace-based blind channel estimation technique for multi- input multi-output (MIMO) orthogonal frequency-division multiplexing (OFDM) approach based on tracking the subspace recursively. The recursive subspace algorithm has a computational complexity of O(J²) , where the J is the input vector dimension. The simulation results show that the improved estimator´s capability is similar to the source approach, but deeply decrease the computational complexity.