Spread spectrum baseband modulation of magnetic fields for communications and proximity sensing
US6393045B1 · kind B1 · utility
38Cited by
24References
16Claims
0Family size
Assignee
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Key dates
| Filing date | Sep 24, 1998 |
| Grant date | May 21, 2002 |
| Priority date | — |
| Expiry date | Sep 24, 2018 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG06K7/083
- WIPO fieldComputer technology
- WIPO sectorElectrical engineering
Abstract
A magnetic field-based tagged object information storage and retrieval system employs a spread spectrum modulated magnetic field for identifying each of a plurality of tagged objects to which spread spectrum modulation magnetic field transponders are attached. When interrogated by a tag reader, transponders embedded in plural tags generate spread spectrum modulated magnetic fields that are correlated with a reference spreading sequence in a tag reader signal processor to both detect and identify each responding tag.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.