Journal Article

Doppler spread analysis for suppressing channel time variation in high‐mobility massive MIMO V2V communications

Zhang, Weile, Yan, Zeyu, Li, Fuqiang

2024

Overview

Here, fast time‐varying channels of high‐mobility vehicle‐to‐vehicle communications for massive multiple‐input multiple‐output orthogonal frequency division multiplexing systems are considered. Large‐scale uniform linear arrays are configured at the transmitter and receiver to separate multiple angle domain Doppler frequency offsets based on transmit and receive beamforming with high spatial resolution. Then, each beamforming branch comprises only one dominant Doppler frequency offset. Next, the conventional channel estimation method is performed for each beamforming branch, and carry out maximum‐ratio‐combining for data detection. Power spectrum density and Doppler spread of the equivalent link between the transmitter and receiver are derived and regarded as the criterion for assessing the residual channel time variation caused by limited antennas in practice. Interestingly, a scaling law between the asymptotic Doppler spread and the number of transceiver antennas shows that asymptotic Doppler spread is proportional to the maximum Doppler frequency offset and decreases at the rate of 1NT2+1NR2 $\\sqrt {\\frac{1}{{{N_T}^2}} + \\frac{1}{{{N_R}^2}}}$ , where NT ${N_T}$and NR ${N_R}$are the number of transmit and receive antennas, respectively. Simulation results confirm the validity of the proposed Doppler suppression framework in high‐mobility vehicle‐to‐vehicle communications. We propose a novel Doppler suppression framework with Doppler frequency offset compensation at the transceiver in angle domain to suppress channel time variation for vehicle‐to‐vehicle communications. We regard Doppler spread as the criterion for assessing the residual channel time variation and derive the scaling law between Doppler spread and the number of transceiver antennas. Simulation results confirm the validity of the proposed Doppler suppression framework for high‐mobility V2V communications.

• Publisher: Wiley
• Subject: Doppler shift / MIMO communication / OFDM modulation / time‐varying channels