Teleterminal system [mobile data communication]

A teleterminal system is described that has been designed in response to the needs of mobile data communication. The system provides services by radio packet transmission with multichannel access techniques in small radio zones. The system features efficient frequency spectrum use, large subscriber capacity, and a small and light data terminal, and integrates radio transmission with packet switching and computer communication. Both automatic repeat request (ARQ) and authentication are adopted in the radio link. The system is virtually error free and is provided with a countermeasure against unauthorized invasion. A pilot system has been developed and experimentation was done for investigation and confirmation on a system design. More than an 80% coverage of service area is obtained in each zone to satisfy a BER of 1×10^-3