Joint channel and delay aware user scheduling for multiuser MIMO system over LTE-A network

Existing mobile video applications are continuously driving up the demand for throughput and better quality of service (QoS) for future Long Term Evolution-Advanced (LTE-A) networks. Multi-User Multiple-Input Multiple-Output (MU-MIMO) is one of the most promising technologies that would meet the throughput demand. Unfortunately, existing MU-MIMO schemes do not consider metrics such as delay, and therefore, cannot meet the QoS requirement of delay sensitive applications, such as mobile video. We propose a new cross-layer MU-MIMO scheduling algorithm, which is referred to as joint channel and delay aware user scheduling (CDAUS), satisfies both the throughput and delay requirements. The key idea of the CDAUS algorithm is to select users to form MU-MIMO based on the delay requirements of individual users, as well as their channel correlations. The priority of the users is carefully designed to leverage their delay and throughput. Simulation results show that the proposed CDAUS algorithm is able to reduce the average delay by up to 30% with a marginal 2% sacrifice of throughput, compared to previous work. It also reduces delay variations and improves fairness among the users.