Adaptive Multiuser Transmission Using Millimeter Wave Beam Alignment with User Selection

We develop a channel-adapted multiuser transmission algorithm for millimeter wave (mmWave) wireless systems. We first study the impact of multiuser diversity on the beam alignment performance of mmWave systems. Assuming a multiuser framework, we derive the probability of beam misalignment as a function of the number of users. Moreover, we estimate the achievable sum-rate of multiuser systems relying upon beam alignment. We develop an adaptive transmission algorithm that changes the number of scheduled users according to channel conditions. Simulation results verify that the proposed algorithm provides better sum-rate performances than previous systems.