Detection system and method of operating same.

摘要

In an improved detection system of the type wherein detectors (13 to 18) are linked to a central monitoring unit (11, 12) by radio, each detector includes a radio receiver (22) as well as a transmitter (23) and also includes a timer (24) to control the timing of the operation of the receiver and transmitter. The monitoring unit is able to transmit to each detector a synchronisation signal to coordinate the operation of the timers. Signals from the detectors are transmitted to the monitoring unit in predetermined sequence, with the result that overlapping of signals, and the confusion which may otherwise arise, are avoided. <IMAGE>