The Mobitex packet-switched radio data system

This paper is a systems engineering overview of a state-of-art packet switched radio data system-the Mobitex system. RAM Mobile Data operates Mobitex systems in the US and the UK. Mobitex systems are also in operation in Scandinavia and Canada. The system architecture is `open´, which allows any company to enter the wireless data business by providing radio modems and/or application software conforming to the Mobitex interface specification. This paper first outlines the Mobitex network architecture, network protocol, RF system design and the Mobitex `open´ air interface. Finally, the spectral efficiency and response time for transmission of short messages using a wireless packet data network and present day analog cellular systems are compared. It is concluded that a wireless packet data network is superior to analog cellular systems both in terms of spectral efficiency and response time for short data messages