Downlink scheduling for user equipment served by multiple mobile terminals in cellular systems

Abstract

An opportunistic downlink scheduling algorithm, which is referred to as Scheduling scheme for Multiple Mobile Terminals Serving the same User equipment (SMMTSU), is presented for the case when there exists User Equipment (UE) that is served by multiple Mobile Terminals (MTs) in a time-slotted cellular system. We study three scenarios, namely (i) when the MTs are served by the same cellular provider but scheduler has no knowledge of the presence of such UEs; (ii) when the MTs are served by the same cellular provider and the scheduler located in the base station knows the presence of such UEs; and (iii) when such MTs are served by different cellular providers. We establish the optimality and present the main properties of SMMTSU for scenario (ii). In scenario (iii), we show that it is better to use the MTs from one cellular provider using SMMTSU rather than from different cellular providers. Simulations under High-Speed Down-link Packet Access (HSDPA) model are implemented which show that SMMTSU works well and provides an approximately 20% throughput improvement for the UEs in scenario (ii) as compared to scenario (i). The simulation results also show that there is generally a 7% throughput benefit if the users take service from a single cellular provider. © 2012 Elsevier B.V. All rights reserved.