COMMUNICATIONS SYSTEMS

摘要

The telecommunications system comprises a plurality of distributed base stations (BS1..BSn) each operatively coupled to a public switched telecommunications network (PSTN) and being adapted to co-operate with one or more of a plurality of portable cordless telephone units (CT1..CT4) by way of a plurality of cordless digital communication channels operating on a time division duplex basis. The base unit (BS1..BSn) is arranged upon detection of an incoming public switched network call, to poll all the portable cordless telephone units (CT1..CT4) by transmitting on a repetitious basis the identity of the portable units to be connected to the incoming call on a selected channel and the base unit (BS1..BSN) is arranged to intersperse each poll operation with a signalling message. Each portable unit (CT1..CT4) is arranged to scan the cordless channels at a predetermined interval and the base unit (BS1..BSn) is adapted to postpone the sending of a ringing message to any of the portable units (CT1..CT4) until a predetermined period has elapsed since the commencement of the polling action, the predetermined period being substantially similar to but larger than the predetermined interval.