초록 ▼

In a system for monitoring, within a preselected distance or location defining the perimeter of a preselected distance, and locating the position of persons, animals or moving objects, a base-station generates an interrogation signal which, when detected by one or more transceiver units triggers the

In a system for monitoring, within a preselected distance or location defining the perimeter of a preselected distance, and locating the position of persons, animals or moving objects, a base-station generates an interrogation signal which, when detected by one or more transceiver units triggers the one or more of the transceiver units to generate a return signal. Each of the transceiver units, upon being located outside the preselected distance or upon becoming inoperable, detects an interruption in the interrogation signal, ceases to generate the return signal, alerts the user of the transceiver unit and, after a delay period, triggers a homing signal. The base-station, upon detecting an interruption in the return signal from any one of the transceiver units, triggers a delay period for that transceiver unit and, upon expiration of the delay period, triggers locating circuitry to determine the position of the transceiver unit. Moreover, the base-station operates independently for each of the one or more transceiver units.

대표청구항 ▼

A monitoring and locating system comprising: a base-station and a plurality of remote transceivers, said base-station provided with means for generating a plurality of distinct interrogation signals for receipt by said plurality of remote transceivers at a preselected interrogation distance from sai

A monitoring and locating system comprising: a base-station and a plurality of remote transceivers, said base-station provided with means for generating a plurality of distinct interrogation signals for receipt by said plurality of remote transceivers at a preselected interrogation distance from said base-station each of said plurality of distinct interrogation signals communicates with a respective one of said plurality of remote transceivers; said base-station provided with means for detecting and distinguishing between the receipt of a plurality of homing signals; said base-station provided with means for detecting the receipt or interruption of each of said plurality of distinct return signals generated by said plurality of remote transceivers and for alerting a user of said base-station of the interruption of each of said plurality of distinct return signals; said base-station provided with means for locating a source of said plurality of homing signals generated by said plurality of said remote transceivers; said plurality of remote transceivers each operable to detect one of said plurality of distinct interrogation signals within said preselected distance from said base-station; each one of said plurality of remote transceivers provided with means for generating a distinct return signal in response to receipt of a respective one of said distinct interrogation signals; each one of said plurality of remote transceivers provided with means for detecting the receipt or interruption of said interrogation signals and for alerting a user of one of said plurality of remote transceivers upon said detected interruption at said user\s remote transceiver that said user\s remote transceiver has moved beyond said preselected interrogation distance; and each one of said plurality of remote transceivers provided with means for generating a homing signal in response to moving beyond said preselected distance from said base-station.