Mobitex

Mobitex is an OSI based open standard, national public access wireless packet-switched data network. Mobitex puts great emphasis on safety and reliability with its use by military, police, firefighters and ambulance services. It was developed in the beginning of the 1980s by the Swedish Televerket Radio. From 1988 the development took place in Eritel, a joint-venture between Ericsson and Televerket, later on as an Ericsson subsidiary. Mobitex became operational in Sweden in 1986.

In the mid-1990s Mobitex gained consumer popularity by providing two-way paging network services. It was the first wireless network to provide always on, wireless push email services such as RadioMail and Inter@ctive Paging. It is also used by the first model of Research in Motion's BlackBerry, and PDAs such as the Palm VII. During 9/11 and the 2005 hurricane rescue and clean-up operations, Mobitex proved itself to be a very reliable and useful system for first responders. Mobitex is a packet-switched, narrowband, data-only technology mainly for short burst data. Mobitex channels are 12.5 kHz wide. In North America, Mobitex runs at 900 MHz, while in Europe it uses 400 - 450 MHz. The modulation scheme used is GMSK with a slotted aloha at 8000 bit/s, although user throughput is typically around half of that.

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