Efficient multiuser MIMO scheduling strategies

For multiuser MIMO (MU-MIMO) services, orthogonal multiple accesses, e.g., FDMA and TDMA are popular options to avoid multiuser interference. A high sum-rate is achievable in an MU-MIMO system where a common frequency or time resource is shared by multiple users if transmitters assume perfect knowledge of the corresponding channels. In this paper, we focus on the scheduling mechanism for angle-frequency subchannels. For the channel identification, we propose two efficient scheduling strategies to make MU transmit simultaneously without serious packet collisions. With the proposed approaches, the packets transmitted to different subscriber units can be scheduled efficiently at the access point to increase the channel utilization and decrease the average packet delay.