关键词: 半盲信道估计, 子空间分解, 子载波分组, WR分解

Abstract: The channel estimation plays an important role in the MIMO-OFDM systems to achieve the high transmission performance. A new semi-blind channel estimation based on subspace for MIMO-OFDM systems is proposed. The channel matrix is decomposed by two parts. The first part is estimated by received data using the subspace method. By exploiting the frequency correlation among adjacent OFDM subcarriers, the method can reduce the?computational complexity by 80 percent and performance is improved by 1~2 dB, compared with the classical method. The second part is a rotation matrix, which is estimated by employing pilot symbols. The proposed method is validated through computer simulation-based experimentations, and simulation results show the effectiveness of the algorithm.

Key words: semi-blind channel estimation, subspace decomposition, subcarriers subset, whitening-rotation