Fig 1 - uploaded by Suleiman Y. Yerima
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Simplified diagram of HSDPA enabled UMTS Radio Access Network (UTRAN) topology showing the main entities
Source publication
High Speed Downlink Packet Access (HSDPA) refers to enhancements to UMTS (Universal Mobile Telecommunications System) cellular networks to provide higher capacity for new packet switched services. End user communication sessions with mixed diverse traffic flows such as voice, video and data are expected to characterise certain multimedia services o...
Contexts in source publication
Context 1
... to transmit data to the User Equipments (UE) over the downlink of a HSDPA enhanced UMTS cell. It provides better end-user experience, with shorter connection and response times. In addition, three to five fold sector throughput can be achieved, resulting in significantly more data users in a cell. A simplified UMTS/HSDPA architecture is shown in Fig. 1 ...
Context 2
... discard timer can be used to drop VoIP PDUs likely to exceed the scheduling delay budget, but the adverse effect is increased loss of VoIP PDUs which would degrade voice quality. Moreover, observe from Fig. 10 that the average UTRAN PDU delay for 20 and 30 users using FCFS is about 120ms and 180ms respectively which will render a discard time ...
Citations
... In HSDPA (High-Speed Downlink Packet Access) technology, it is possible to implement Packet scheduling algorithms that support multimedia traffic with diverse concurrent classes of flows being transmitted to the same end user [9]. Therefore, Suleiman and all present in [16] a queuing model for multimedia traffic over HSDPA channel using a combined time priority and space priority (TSP priority) with threshold to control QoS measures of the both RT and NRT packets. The basic idea of TSP priority [2] is that, in the buffer, RT packets are given transmission priority (time priority), but the number accepted of this kind of packets is limited. ...
... Thus, TSP scheme aims to provide both delay and loss differentiation. Authors in [16], [17] studied an extension of TSP scheme incorporating thresholds to control the arrival packets of NRT packets (Active TSP scheme), and show, via simulation (using OPNET), that TSP scheme achieves better QoS measures for both RT and NRT packets compared to FCFS (First Come First Serve) queuing. To model the TSP scheme, mathematical tools have been used in [18] and QoS measures have been analytically deducted, but some given results are false, ([5],[6],[9]) corrected this paper and used MMPP and BMAP processes to model the traffic sources. ...
When different type of packets with different needs of Quality of Service (QoS) requirements share the same network resources, it became important to use queue management and scheduling schemes in order to maintain perceived quality at the end users at an acceptable level. Many schemes have been studied in the literature, these schemes use time priority (to maintain QoS for Real Time (RT) packets) and/or space priority (to maintain QoS for Non Real Time (NRT) packets). In this paper, we study and show the drawback of a combined time and space priority (TSP) scheme used to manage QoS for RT and NRT packets intended for an end user in High Speed Downlink Packet Access (HSDPA) cell, and we propose an enhanced scheme (Enhanced Basic-TSP scheme) to improve QoS relatively to the RT packets, and to exploit efficiently the network resources. A mathematical model for the EB-TSP scheme is done, and numerical results show the positive impact of this scheme.
