TELECOMMUNICATIONS SYSTEM INCORPORATING PORTABLE COMMUNICATIONS UNITS

摘要

TELECOMMUNICATIONS SYSTEM INCORPORATING PORTABLE COMMUNICATIONS UNITS The invention relates to the incorporation of an alternative to the public telephone kiosk or payphone in a telecommunication system. It provides a telecommunication system having communication terminals connected to it, and portable communication units for the users. Each communication unit includes a transmitter and receiver enabling coupling to any of the communication terminals over a short range together with a credit meter adapted to co-operate with the communication terminal and to have its credit level adjusted by the telecommunications system's callcharge metering arrangements. By such an arrangement individual users have and carry with them their own portable telephone units which are of similar size to a pocket calculator. In order to make a call the user positions himself within some standard range (e.g. 5 meters) of any one of the communication terminals and then operates his communication unit to gain access to the telecommunications system by way of the communication terminal. The portable communication unit comprises a push-button dialler, a liquid crystal display and integral earpiece and microphone extendable to the normal spacing from the earpiece using an acoustic tube. Access to the telephone system is gained by performing an interactive key code sequence using the communications unit. When access is confirmed by the communication terminal the user keys in the required telephone number and when the call is established the terminal indicates call cost information over the reverse speech link. The unit includes a PROM as a credit meter and the cost information cancels the requisite credit from the memory.