Patent ID: 6166642
Filing Date: 2000-12-26
Classification: G08B

Abstract:
An electronic tracing system for sensing when a movable subject moves more than a predetermined distance from a base location, said system comprising:a first module,said first module including attaching means for attaching said first module to said movable subject, first processing means, first transmitting means and receiving means, said first processing means adapting said first module to alternately broadcast location signals from said first transmitting means and change to a receiving mode between said broadcasts; anda second module for disposing at said base location, said first and second modules being a distance apart,said second module including detecting means, second processing means, an alarm device, second transmitting means, a timer and cancelling means, wherein said detecting means being adapted to detect said location signals, said second processing means processing said location signals to determine whether said distance apart of said modules exceeds said predetermined distance, said second processing means activating said alarm device when said second processing means determines that said distance apart of said modules exceeds said predetermined distance and said timer is activated to measure said time, and said second transmitting means being operable to transmit an alarm signal to said first module upon activation of said alarm device said second transmitting means transmitting said alarm signal after a specified period of said time has elapsed unless said cancelling means is activated before then, said receiving means being adapted to receive said alarm signal.