Channel compensation based on VPS and time-frequency interferometry for massive MIMO-OFDM

Massive MIMO has been recognized as promising ways to provide high speed data transmission. However, since the number of pilot symbol is proportionally depending on the number of transmit antenna, the total transmission rate of massive MIMO would be degraded. To solve this problem, channel estimation by virtual pilot signal (VPS) with a few pilot signals has been proposed. However, since the conventional method iteratively identifies the channel state information (CSI), the complexity is considerable work. Then again, time-frequency interferometry (TFI)-OFDM has been proposed. This method can achieve a good BER performance with a few pilot symbols. In this paper, we propose a novel channel compensation based on VPS and TFI for massive MIMO without increasing the system complexity. The proposed scheme has a low complexity, with improving BER performance to compared with the conventional method using linear interpolation and FFT/IFFT after specific operations. From the simulation results, the proposed scheme can improve BER performance to compared with the conventional method in 4 × 4 and 8 × 8MIMO systems.