Angle-of-departure-aided opportunistic space-division multiple access for MIMO applications

This paper introduces a novel transmission technique for MIMO broadcasting directional channels, herein called the Angle-of-Departure-Aided Opportunistic Space-Division Multiple Access (AOD-OSDMA) technique. In AOD-OSDMA, the knowledge of angles-of-departure (AODs) at the BS of the strongest signal received by each user is used to design multiple opportunistic beams so that advantage is made of the clustering nature of wireless channels. Compared to the OSDMA-S using 4 × 2 (8 × 2) MIMO system, the proposed technique provides gains in system capacity of up to 50% (160%), and reduces the number of channel directional feedback bits by 33% (55%), when evaluated using MIMO directional channel model such as WINNER.