Use of rotating magnetic field to enhance communication with RF burst-transmitting tags of object location system
US6812839B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | Mar 27, 2001 |
| Grant date | Nov 2, 2004 |
| Priority date | — |
| Expiry date | Jun 21, 2022 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01V15/00
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
Magnetic field-based communication with an object is enhanced by generating a rotating AC magnetic field that effectively ensures magnetic field coupling with the magnetic field sensor of the object, irrespective of the orientation of the object. The rotating AC magnetic field is produced by a diverse spatial orientation (a two-dimensional arrangement) of a plurality of magnetic field coils, and the driving of those coils in a prescribed phase relationship (e.g., in phase quadrature) to realize a composite AC magnetic field that rotates (at the carrier frequency of the coil drive signal) over the entirety of the spatial coverage area.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.