Performance evaluation of VoIP and web services in HSDPA

During the last years, the mobile communications market in the western developed countries has reached a standstill, with a market penetration higher than 100% in most countries such as, Spain 115%, United Kingdom 120% and Italy with more than 150%. So the network operators have focused their strategy in moving into a new market still developing, the data, that could help the operators to increase their saturated income. The solution mostly adopted by the operators is to offer the mobile broadband offering flat rate schemes to the customers for a monthly fee. The mobile broadband appeals to wide range of users, such as corporate users and especially to students which give them the liberty to access internet across different locations such as university, cafe or shared accommodation. That creates a set of challenges to the operators having to improve their network in order to cope with this huge new demand for high-speed data, to successfully satisfy these requirements, Third Generation networks must support high user data rates, especially on the downlink direction of the communication path due to its heavier load. For these reason, the 3GPP standardized in Release 5 the technology HSDPA (High Speed Downlink Packet Access). The HSDPA provides a cost effective solution to provide high-speed data to the customers specially focused to increase the overall cell capacity thanks to the fact that the resources are shared among the users. This project has consisted on the design of a HSDPA simulator and on the evaluation of the performance of VoIP and web browsing traffic in HSDPA. The idea of this project started on an industrial placement in Orange UK, in the department of Access Network. Between other tasks the CQI (Channel Quality Information) were modelled using samples taken from the live network. In order to do a more theoretical analysis and make use of the CQI modelling, after the placement, the design of the complete simulator has been made under the direction of Professor Ferran Casadevall. The objective of this project is then to simulate an HSDPA cell in different conditions, specially focused in different cell loading conditions such as: · Different number of users, up to 100 users per cell. · Different traffic profiles, choosing between VoIP and web users. Once the simulations have been carried out, the results have been analysed in detail, offering figures and facts of how the throughput and the traffic delay changes with different load conditions. As both the VoIP and web traffic have different thresholds of maximum delay defined by international entities, the simulations could be used to asses to define, the maximum number of HSPDA users in cell. This will help to capacity planners to decide the rollout strategy, based on the simulation results. This project has been developed with the tool Matlab. This tool has been chosen because it allows an effective code development and at the same time it is very useful to produce graphics and to compute difficult numerical calculations