Abstract: A cellular mobile telephone system and method in which channel assignment and telephone call routing are controlled by a central control station and in which each communications channel is separately controlled at a cell station by a radio interface module ("RIM") associated therewith. Flexibility and security from operational interruptions is provided by dynamic assignment of identical RIMs to monitoring, paging, control and communication functions at the cell station. The system is modular and may be customized to accommodate geographic and demographic considerations, while permitting expansion and modification without obsolescence. The system also includes novel, self-diagnostic testing loops and methods. A novel mobile telephone is also disclosed.