Angle of arrival-based interference mitigation and spatial grouping techniques for Hetnet

摘要

When the femtocell base station has perfect channel state information, it can adopt beamforming to avoid interference. However, the perfect channel assumption may not be practicable due to the channel-state information delay, channel estimator error, and bandwidth wastage while reporting channel parameters. In this paper, we proposed an angle of arrival (AOA) based beamforming structure for orthogonal frequency division multiple access (OFDMA)-based Hetnet systems. The proposed scheme has interference resistant capability without the needs in the estimation of the channel parameters and the calculation of beamforming weight vector for each subcarrier. It can also reduce extra burden and delay generated from communication link between the femtocell and the central entity for using beamforming technology. The AOA estimates are also utilize to modify the spatial grouping method appears in [1].