System for and method of locating radio frequency identification (RFID) tags associated with items in a controlled area
US9111190B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Jan 16, 2013 |
| Grant date | Aug 18, 2015 |
| Priority date | — |
| Expiry date | Jul 29, 2033 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01S2013/0245
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
A radio frequency identification (RFID) tag reading system having a phased antenna array accurately locates RFID tags in a controlled area, by steering an interrogating beam over the controlled area to interrogate the tags and generate return modulated RF signals. A primary receiver steers a primary receive beam at a primary steering angle that is fixed during each tag interrogation. A primary demodulator demodulates and reconstructs the received return modulated signals. A secondary receiver, independently of the primary receiver, steers a secondary receive beam at a plurality of secondary steering angles. A secondary correlator/demodulator demodulates the combined return modulated signals, and utilizes the reconstructed signal reconstructed by the primary demodulator at each of the secondary steering angles. Both the primary and the secondary receivers cooperate to accurately locate the same tag.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.