Dynamic resource allocation for delay-tolerant services in downlink OFDM wireless cellular systems

Abstract

The paper develops a framework for relating system performance to a user scheduling mechanism in downlink OFDM mobile cellular systems for delay-tolerant traffic. The performance of dynamic resource allocation techniques using best user (BU) and round robin (RR) strategies for user scheduling, and best sub-carrier assignment with power constraint and interference learning (BSA-PC-IL), is evaluated in terms of the fraction of satisfied users and system spectral efficiency (in kbps/MHz/cell). Simulation results indicate that in a low-mobility, single-cell environment, RR performs better than BU. However, in a high-mobility environment, BU significantly outperforms RR for both single-cell and multi-cell mobile systems. In a slow-mobility, multi-cell environment, BU has a slightly better performance than RR. In general, the BU scheme has a much slower degradation rate in the fraction of satisfied users at increased system loads than the RR scheme.