The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Jan. 02, 2001
Filed:
Apr. 15, 1999
Leonard Schuchman, Potomac, MD (US);
Lloyd Engelbrecht, The Sea Ranch, CA (US);
ITT Manufacturing Enterprises, Inc., Wilmington, DE (US);
Abstract
A monitoring and location system comprising a service center from which movement to and from a prescribed local area and a prescribed wide area is to be monitored. Each member of a class being monitored is provided with a personal RF transponder unit (RFTU). Each RF transponder unit has a digital electronic identification number (DEIN) embedded therein for transmission by RF upon request. RF transceiver interrogation units define specific egress/ingress zones for the prescribed areas. Each interrogation unit being connected to the service center to god signal (1) when an RFTU has egressed or ingressed a prescribed area and (2) the DEIN embedded therein. The RF transceiver interrogation units can determine distance and bearing to a given RFTU and DEIN. When there are a plurality of cell sites encompassing the prescribed areas, an RF transceiver interrogation unit at each of the cell sites, respectively, are connected to the service center. Each RFTU has an emergency signalling component which, when activated, causes a range and bearing measurement to that RFTU to be made and sent to the service center for action.