Davood Molkdar

System level performance evaluation of GPRS for various traffic models

During the GSM standardisation process data services were provisioned for. However, these were based on circuit switched connection. It is now widely accepted that circuit switched connection does not provide optimum utilisation of a communication channel for data transfer. The provision of more efficient radio data bearers has become an essential piece of the existing technologies such as GSM and the future ones such as UMTS. In GSM, ETSI finalised a new packet data service called GPRS in mid 1998. The GPRS data rates will provide bit pipes in the range 8-20 kbps per time slot. GPRS will be deployed in existing GSM networks that have been optimised for voice (circuit switched data) traffic. This paper investigates the system level performance of the GPRS coding schemes in such networks using a system level simulator. The performance is quantified in terms of the throughput and delay for various types of traffic. The results can be used to generate optimisation rules and efficient resource management algorithms.

Performance analysis of varying the link adaptation BLER switching point in EGPRS

This paper examines the impact of the choice of the link adaptation BLER switching point on the performance of Enhanced General Packet Radio Service (EGPRS) Phase I, with the aim of determining the optimum switching point. The analysis is carried out by considering outputs from a system level simulator and a system dimensioning and planning tool. Results are presented for both LA and IR for a range of LA switching points. A GSM macrocellular environment, having an interference-limited 4/spl times/3 re-use pattern, was chosen. The mobiles operate with perfect receivers in a variety of radio channel conditions.

System level performance evaluation of EGPRS in GSM macro-cell environments

This paper provides-under a simulation environment-the downlink system level performance of EGPRS Phase I in GSM interference limited macro-cellular environments. Various scenarios are investigated by considering the throughput and delay statistics at the system level and user level. An interference limited macro-cellular environment; populated with mobiles operating with perfect receiver under the Tu50-NoFH radio condition and receiving e-mail, is considered for two cell re-use pattern scenarios; 4/spl times/3 and 1/spl times/3 (frequency hopping). The main input parameters varied to evaluate the performance under the above scenarios include operating BLER and the number of time slots allocated to EGPRS on a GSM carrier. The results represent the perfect link adaptation (LA) case with no incremental redundancy (IR).

Simulation results of a typical GSM picocellular system

In this paper, simulation results of a typical GSM distributed base station transceiver (BTS) picocellular system under two cell configurations; three overlapping pico-cell base stations and four overlapping pico-cell base stations in which two are co-channel, are presented. The results presented are the call blocking rate, the handover blocking rate and the offered traffic which are used to evaluate the performance, per cell configuration, under two settings of the base station sub-system (BSS) database parameters; non-optimised and optimised. The results show that by taking into account the relative positions of the picocell BTSs and their respective service areas, the BSS database parameters can be optimised prior to the deployment of a picocellular system.

Comparison between simulation and analytical methods of UMTS air interface capacity dimensioning

This paper provides a comparison between the UMTS downlink circuit switched capacity results obtained using a comprehensive system level simulator with those obtained using an advanced analytical method. For the scenarios considered, the agreement varies in the range of 0-15%. Considering the approximation used in the analytical model in regard to the network layout (single cell placed on an imaginary uniform grid), the run-time is about 30 times faster than the simulator described here. With this level of accuracy and such speed, quick investigation of capacity sensitivity to various parameters or first pass dimensioning is facilitated using the analytical model. However, simulation tools such as the one described in this paper are the only means of planning, optimising and testing real systems and their features.

Techniques to provide coverage and capacity in GSM picocellular environments

In this paper various techniques, hereafter referred to as deployment techniques, to provide capacity and coverage inside buildings for GSM cellular mobile telephony system are described. The techniques described are dedicated or undedicated, indicating a system specifically designed for in-building coverage or coverage is achieved by using the macro- or micro-layers, respectively. In addition, the criteria that should be considered in the selection process of a particular deployment technique are described. Finally, the deployment techniques described are graded based on the criteria defined so that a deployment technique that satisfies a specific set of criteria can be selected.

System level performance evaluation of EDGE Compact

EDGE Compact has been developed to enable the deployment of an EGPRS system by utilising only 0.6 MHz worth of spectrum. The implication of using such a narrow spectrum is that system loading becomes a critical factor in maintaining an acceptable QoS service from the users perspective. This paper investigates - under a simulation environment - the performance of 1:3, 2:6, 3:9 and 4:12 EDGE Compact. The scenarios are analysed by varying system loading and considering system throughput and user delay statistics with and without admission control. The results are particular to the population of mobiles operating with perfect receiver, under TU50-NoFH radio condition, E-mail traffic and perfect link adaptation.