Advanced packet scheduling for efficient video support with limited channel feedback on MIMO LTE downlink

Next-generation mobile networks will provide users with high data rates, increased mobility and various services. The initial step made in LTE and LTE-A is adopting the OFDM(A) air interface and utilization of dynamic resource allocation techniques maximizing the cell throughput and coverage as part of enhanced radio resource management functionality. Moreover, the control of the network resource division among users is performed by packet scheduler and different scheduling strategies are applied according to traffic scenario. Typically, video traffic (real-time video streaming, mobile TV etc.) requires higher data rates and certain quality of service (QoS) constrains, i.e. packet size, arrival rate, head-of-line (HOL) packet delay, etc. In this article, we propose a flexible and fairness-oriented packet scheduling approach for real-time video delivery, built on advanced QoS-aware multiuser proportional fair (PF) scheduling principle. Special emphasis is put on practical feedback reporting schemes, including the effects of mobile measurements and estimation errors, reporting delays, and feedback quantization and compression. The performance of the overall scheduling and feedback reporting process is investigated in details in terms of cellular system capacity, resource allocation fairness and video traffic QoS guarantees. Experimental results reveal the bounds of real-time video traffic support on LTE downlink.