| 摘要 |
<p>A person locating system (10) for detecting the unauthorized exit of a person from a monitored area (18) and locating the person thereafter, including a boundary transmitter (52) which generates an activation signal that is conducted across a conductor (16) connected to the boundary transmitter (36). The conductor (16) extends along a boundary of the monitored area (18) and transmits the activation signal within an activation zone (15) adjacent the conductor (16). The person to be monitored wears a portable module (22), which remains in a low power consumption, standby mode until the person enters the activation zone (15) adjacent the conductor (16). The portable module (22) receives the activation signal and enters an active mode wherein the portable module (22) transmits a high frequency locator signal (for example, 220 MHz). The locator signal is received by a locator receiver (28), which may be installed in a facility within the monitored area (18). The locator receiver (28) may also be portable so that the person to be monitored can be tracked down and recovered. In an alternate embodiment, the portable modules (22) are encoded with unique identification information which is transmitted as a part of the locator signal. The locator receiver (56) decodes this information and displays the identification of the wearer of the portable module (22) on a display (64).</p> |
