Utility based Dynamic Subcarrier Allocation for QoS Guarantees in SC-FMDA System

Abstract

Two utility based dynamic subcarrier allocation (DSA) algorithms: the max exponential utility (MEU) algorithm and the max weighted exponential utility (MWEU) algorithm are proposed for quality of service (QoS) guarantees in single carrier frequency division multiple access (SC-FDMA) system. With the objective of maximizing the system total utility, the two proposed DSA algorithms are designed based on a cross-layer manner so as to guarantee the diverse QoS requirements of real-time traffic. The proposed MEU algorithm exploits the property of the exponential utility function to provide higher allocation priority for the user in heavy traffic load. Furthermore, the MWEU algorithm is proposed as a kind of priority adjustable DSA scheduling by introducing the grading theory and the weight factor into the utility function. Simulation results indicate that the MEU algorithm is able to achieve outstanding average delay and system rate-sum capacity performance. And the MWEU algorithm can further improve the delay variance and delay violation probability performance by setting appropriate allocation weights. It is also concluded that the adaptive weight factor value of the MWEU algorithm can be derived according to the practical QoS requirements and average packets arrival rate.