The mobile radio communications industry has recently witnessed a new demand for terminal equipment which can provide both communications and position reporting capabilities on a global scale–for example, the automatic monitoring of secure cargoes during international transportation. Thus, there is much interest in the development of land mobile satellite terminal equipment in the form of a single integrated unit which can economically provide both of these facilities. In this paper the development of such a unit is considered using the Inmarsat-c satellite communications service and the Navstar Global Positioning System (GPS), with extension to GLONASS possible in a receive-only version.
