Delay constrained multiuser scheduling schemes based on upper-layer performance

Different from conventional multiuser scheduling schemes targeting on optimizing the physical layer performance criteria such as Shannon capacity and error probability, in this paper we propose a family of new scheduling methods that take the packet throughput in upper-layer protocols into considerations. This new performance metric appears to be an elegant combination of spectral efficiency and channel reliability, which are two usually competitive performance indicators for practical transmitters and receivers. Our results show that regarding the packet throughput, the proposed schedulers may result in great performance advantage over conventional schemes, especially at low to intermediate SNR. Furthermore, the amount of system delay for each user is investigated together with packet throughput for scheduling algorithm designs. A novel scheduler, considering both system performance and user delays, is then proposed, and the corresponding delay-throughput tradeoff curve is drawn, which actually provides a useful and flexible platform to evaluate any scheduling schemes, if both factors are under concern