Location of objects
US5214410A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Jul 9, 1990 |
| Grant date | May 25, 1993 |
| Priority date | — |
| Expiry date | Jul 9, 2010 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG06K7/10069
- WIPO fieldComputer technology
- WIPO sectorElectrical engineering
Abstract
A locating system 10 for locating predetermined labelled objects 20 includes a transceiver unit 12 which comprises a narrow beamwidth antenna 14 for transmitting an energizing signal 16 at a predetermined first frequency and for receiving a returned signal 22 at a predetermined second frequency from an object to be located, the energizing signal 16 incorporating a predetermined transponder category code. A plurality of label-like transponders 18 is provided, each of which is affixable to an object 20 to be located. Each transponder 18 includes logic circuitry in order that each transponder 18 in a predetermined group of labelled objects 20 constituting the category radiates a returned signal 22, including a transponder identification code, to the transceiver unit 12 in a time-delayed manner so that returned signals 22 are received serially by the transceiver unit 12.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.