Spatially locating RFID tags using multiple readers and correction factors
US7616113B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Jan 4, 2007 |
| Grant date | Nov 10, 2009 |
| Priority date | — |
| Expiry date | Feb 5, 2028 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01Q1/2208
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
An embodiment of the invention is a method of accurately determining the spatial location of an RFID tag in two-dimensions or three-dimensions. The method utilizes a plurality of RFID readers to make a plurality of distance, direction, and or time-of-flight determinations. Such determinations are made by sending a request signal from one of the plurality of RFID readers and listening for a response signal from an RFID tag received at each of the plurality of RFID readers. Correction factors are then determined and the time-of-flight factors adjusted. The adjusted time-of-flight factors are then used to determine more accurately the distances between the RFID tag and each of the plurality of RFID readers. These more accurate distance measurements are then used to determine the spatial location of the RFID tag.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.