Detecting a presence of near field communications (NFC) devices
US8867990B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Feb 29, 2012 |
| Grant date | Oct 21, 2014 |
| Priority date | — |
| Expiry date | Jun 17, 2032 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04W4/80
- WIPO fieldTelecommunications
- WIPO sectorElectrical engineering
Abstract
A near field communications (NFC) device is disclosed that detects a presence of another NFC capable device within its magnetic field. The NFC device generates an unmodulated frequency varying detection sequence to generate a frequency varying magnetic field and/or a modulated frequency invariant detection sequence to generate a carrier-frequency invariant magnetic field. The NFC device samples these magnetic fields and compares these samples to various a priori known responses of various objects to determine whether another NFC device is present within the frequency varying magnetic field and/or the carrier-frequency invariant magnetic field.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.