The integration of Globalstar satellite system with the GSM terrestrial network

Synopsis: In sight of the impressive growth of mobile telecommunication subscribers, a key factor for success is the use of global mobility. Probably, the success of the GSM (Global System for Mobile communication) system is due to the capability to roam in different countries allowed to the GSM subscribers. In order to provide a real global mobility, the terrestrial cellular networks have to integrate with a wider coverage by satellite. Among the incoming Mobile Satellite Systems (MSS), Globalstar, through his 48 low orbit satellite constellation, will allow an effective global coverage. The Globalstar system will be able to be integrated with several terrestrial cellular network. Specifically, in the territories where GSM has been adopted, Globalstar and the GSM networks shall be fully integrated. Elsacom S.p.A., a Finmeccanica/Elsag Bailey company, is going to provide the Globalstar service in Italy, Germany and most of east European countries. Elsacom has acquired the right to act as an exclusive Globalstar service provider in these territories. In order to provide the Globalstar service, Elsacom has been installing two gateways, the first in Italy and the second in Urkaine, that will collect the subscribers calls and route it to the proper destinations. This article will describe the different possible solutions of the problems concerning the integration of the Globalstar Satellite Network with the GSM cellular network, from both the mobile station and the gateway point of view, and specifically how Elsacom has been integrating his Globalstar gateways into the GSM world.