Angle sweeping and scheduling in downlink opportunistic beamforming systems

In the downlink wireless communication systems, opportunistic beamforming is a practical and widely used technique for user-scheduling. The critical element of the opportunistic beamforming is the beamforming. There are many studies focus on the channel fluctuations but put little eyes on the beam´s angle. In this paper, we investigate system performance if the beam angle changes in a sweeping way. We consider the scheme under cellular network systems and put more eyes on the slow fading channel states. The base stations equipped with smart antennas which generate beams according to the defined algorithm. An angle sweeping scheme is proposed to change the beam angle from 0 to 2π and bring fluctuations to the channel which make the scheduling better. By combining memory function, the proposed scheme is more practical and suitable for the few user circumstance. We also demonstrate the performance of the proposed algorithm through MATLAB simulation.