In this correspondence, we propose a new receiver design for high-mobility orthogonal frequency division multiplexing (OFDM) downlink transmissions with a large-scale antenna array. The downlink signal experiences the challenging fast time-varying propagation channel. The time-varying nature originates from the multiple carrier frequency offsets (CFOs) due to the transceiver oscillator frequency offset (OFO) and multiple Doppler shifts. Let the received signal first go through a carefully designed beamforming network, which could separate multiple CFOs in the spatial domain with sufficient number of receive antennas. A joint estimation method for the Doppler shifts and the OFO is further developed. Then the conventional single-CFO compensation and channel estimation method can be carried out for each beamforming branch. The proposed receiver design avoids the complicated time-varying channel estimation, which differs a lot from the conventional methods. More importantly, the proposed scheme can be applied to the commonly used time-varying channel models, such as the Jakes' channel model.
@article{arxiv.1701.03221,
title = {High-Mobility OFDM Downlink Transmission with Large-Scale Antenna Array},
author = {Wei Guo and Weile Zhang and Pengcheng Mu and Feifei Gao},
journal= {arXiv preprint arXiv:1701.03221},
year = {2017}
}