High-Mobility OFDM Downlink Transmission With Large-Scale Antenna Array

• Published in: IEEE transactions on vehicular technology Vol. 66; no. 9; pp. 8600 - 8604
• Main Authors: Guo, Wei, Zhang, Weile, Mu, Pengcheng, Gao, Feifei
• Format: Journal Article
• Language: English
• Published: New York IEEE 01.09.2017; The Institute of Electrical and Electronics Engineers, Inc. (IEEE)
• Subjects: Antenna arrays; Antennas; Array signal processing; Beamforming; Carrier frequencies; Carrier frequency offset (CFO); Doppler shift; Doppler shifts; Estimating techniques; Estimation; Frequency division multiplexing; high-mobility; large-scale antenna array; OFDM; Offsets; Orthogonal Frequency Division Multiplexing; orthogonal frequency-division multiplexing (OFDM); oscillator frequency offset (OFO); Receivers & amplifiers; Receiving antennas; time-varying channels
• ISSN: 0018-9545; 1939-9359
• DOI: 10.1109/TVT.2017.2695562

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 a 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.