Large-scale array aided beamforming improves the spectral efficiency(SE) as a benefit of high angular resolution.When dual-beam downlink beamforming is applied to the train moving towards cell edge,the inter-beam ambi...Large-scale array aided beamforming improves the spectral efficiency(SE) as a benefit of high angular resolution.When dual-beam downlink beamforming is applied to the train moving towards cell edge,the inter-beam ambiguity(IBA) increases as the directional difference between beams becomes smaller.An adaptive antenna activation based beamforming scheme was proposed to mitigate IBA.In the district near the base station(BS),all antenna elements(AEs) were activated to generate two beams.As the distance from the train to the BS increased,only the minimum number of AEs satisfying the resolution criterion would be activated.At the cell edge,one beam was switched off due to intolerable IBA.The proposed scheme can achieve SE gain to the non-adaptive scheme and show more robustness against the direction-of-arrival(DOA) estimation error.展开更多
基金supported partially by the 973 Program under the Grant 2012CB316100
文摘Large-scale array aided beamforming improves the spectral efficiency(SE) as a benefit of high angular resolution.When dual-beam downlink beamforming is applied to the train moving towards cell edge,the inter-beam ambiguity(IBA) increases as the directional difference between beams becomes smaller.An adaptive antenna activation based beamforming scheme was proposed to mitigate IBA.In the district near the base station(BS),all antenna elements(AEs) were activated to generate two beams.As the distance from the train to the BS increased,only the minimum number of AEs satisfying the resolution criterion would be activated.At the cell edge,one beam was switched off due to intolerable IBA.The proposed scheme can achieve SE gain to the non-adaptive scheme and show more robustness against the direction-of-arrival(DOA) estimation error.