Location-Fair Beamforming for High Speed Railway Communication Systems

In this paper, the transmission scheme for the high speed railway (HSR) communication systems in the presence of Doppler shift is investigated. A fair transmission scheme based on sectored beams, in which there is little variation in the received signal-to-noise ratio (SNR), is proposed. An optimization problem for the beam design is formulated to maximize the expected average power within the beam coverage range with limited variation in the instantaneous received power in different locations. Through numerical results, the proposed transmission scheme is shown to achieve fair performance along the time. Overall, a location-fair solution for improving the fairness of the HSR communication systems is provided.