Dimensioning of GPRS Networks (funded by Libertel, now Vodafone)

GPRS Network Dimensioning

Summary

Libertel (now Vodafone Netherlands) is a mobile service provider in the Netherlands. In the near future the existing GSM network will be extended towards GPRS (General Packet Radio Service). GPRS is a technology which improves the possibilities to access the internet over a wireless link. In particular, higher bandwidths, theoretically up to 170 kbps, are available for a GPRS user. Furthermore, GPRS can be implemented without decreasing the voice user's quality of service. It was developed to utilize the bandwidth which remains unused by voice calls. Therefore, GPRS has to be very flexible in the resource reservation on the wireless link which is achieved by using a packet switched technology.

The introduction of GPRS leads to new challenges for the dimensioning of mobile radio cells. While with circuit switched connections only, the number of frequencies in a cell was determined by the Erlang formula, with GPRS it is more complicated. Additional to the blocking probability of a voice user the performance of a GPRS user is a planning criterion. This performance depends on different factors, the voice traffic, the data user profile, and the GPRS implementation. The objective of the cooperation is to define a stochastic data user model which is used in a simulation of a GPRS cell to derive the quality of service of the user for different traffic profiles and cell configurations.