UMTS medium access control quality of service scheduling

Abstract

The goal of Universal Mobile Telecommunications System (UMTS) is the delivery of multimedia services to the mobile user. Each different service requires its specific Quality ofService (QoS) to satisfy the mobile user. In this paper, a scheduling concept for the Medium Access Control is presented that satisfies the QoS requirements. To validate the scheduling concept a typical mobile user application mix is examined for performance analysis by simulations. A UMTS Radio Inferface Simulafor (URIS) is used that is based on an emulation of the standardized UMTS protocol stack extended by the Transmission Confml Protocol (TCP) and the Internet Protocol (IP). Simulation results of QoS parameters like delay and throughput depict the performance of mobile applications over UMTS.

On the Impact of RLC Layer Configuration Parameters in UMTS Internet Access

“…Thus, several studies propose TCP parameters and mechanisms tuning to improve its performance over the radio link constraints [6], [7], whereas other researchers focus their attention in adjusting the configuration of the UTRAN protocols to reduce the negative impact of the radio interface on TCP. In this second group, different strategies can also be also differentiated: several studies center on radio resource management and medium access control mechanisms [8], [9], whereas others are aimed to the study of RLC layer configuration and its effect on TCP traffic performance [10], [11], [12].…”

Service Multiplexing Over a Tdma Air Interface Using the Flo Concept

“…If a number of TFCs offer the same best possible QoS to the highest priority data, the TFC is selected based on the ability of each TFC to offer the best possible QoS to the next highest priority data, and so on. Of particular interest to our work is the work of S. Heier et al [3,4,5], that presents a number of interesting studies of MAC layer TFC management functionality in UTRAN. These publications all use a fixed TFC allocation technique, similar to that presented in the GERAN standards, for controlling access of the various active TrCHs to the available TFCs.…”

“…Importantly, the research presented in references [3,4,5] identifies the impact transport format management schemes can have on the performance of a system such as FLO.…”