A locating and monitoring system includes transmitters worn by a person,
animal, or equipment to transmit an unique identification code while
moving about a facility. The code is transmitted by pulse bursts at
diverse times during predetermined time intervals to prevent
synchronization with resident signals in the facility. Receivers in the
walls or ceilings of the facility respond to the infrared radiation of
the pulse bursts and validate the identification code by a checksum of
the code through a comparison with a checksum transmitted with the code.
The receivers deliver validated codes to arbitrators and receive back
signals indicative of the level of an individual assigned to a class
wearing the transmitters. Signals from the receivers are received by
arbitrators which forward the codes to a CPU for recording start and stop
events indicative of movement by transmitters into and out of the
reception range of the various receivers.