Semi-blind Channel Estimation and Data Detection for Time-Varying Massive MIMO System

A semi-blind algorithm based on expectation propagation (EP) is proposed for multi-cell massive MIMO systems with spatially and temporally correlated channels. The performance of the algorithm in channel estimation and data detection is obtained from simulations and compared to other approaches. The results show that with only K pilots, where K is the number of users in the cell, the channel estimation performance of the proposed method approaches a lower bound as the number of BS antennas or the number of data symbols per frame increase. As expected, for time-varying channels, the proposed algorithm clearly outperforms those designed for block-fading channel models.