A primary rate guaranteed SDMA for aeronautical communications

In order to achieve an efficient usage of a limited aeronautical spectrum for aeronautical communications, in this paper, a primary rate guaranteed space division multiple access (SDMA) is proposed to support advanced air to ground (A/G) communication systems, i.e., full 4-Dimensional Trajectory based operations. We focus on the random access of a large number of short messages between aircrafts and the ground station. It shows that using a zero-forcing beamforming combined with a low complexity aircrafts grouping strategy, the proposed SDMA is able to improve the spectrum efficiency under a primary rate constraint.