Keywords:
Additional equipment, Calls, Characteristics, Communication service, Communication technology, Data, Data transfer, Definitions, Electrical engineering, ETSI, Information processing, Languages, Radio, Radio equipment, Radio networks, Recalls, Signalling, Speech transmission, Telecommunication, Telecommunication networks, Telecommunication systems, Telecommunications, Telephone networks, Terminology, Terrestrial, TETRA, Trans european trunked radio, Wireless communication services