Interference Mitigation via Scheduling for the MIMO Broadcast Channel with Limited Feedback

The multiple-input multiple-output (MIMO) broadcast channel uses multiple antennas at the transmitter to concurrently deliver information to multiple receivers. Despite the theoretical capacity gains over single user MIMO, the actual throughput of the system with limited feedback on channel state information suffers due to interspatial stream interference. On top of the orthogonal beamforming with limited feedback [1], this paper introduces two novel stream schedulers to mitigate the interference. By the proposed adaptive spatial stream schedulers, an adaptive number of spatial streams are scheduled and thus, reduces the interference, which also achieves power gains by concentrating power into fewer streams. The two proposed algorithms are evaluated and shown to effectively mitigate the interference.