Portable object having multi-level demodulation and being inductively coupled to a fixed station
US7575165B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Sep 14, 2004 |
| Grant date | Aug 18, 2009 |
| Priority date | — |
| Expiry date | May 11, 2026 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG06K19/0723
- WIPO fieldComputer technology
- WIPO sectorElectrical engineering
Abstract
A remote transmission device having a fixed station and a portable object provided with an antenna inductively coupled to the station, the object having a variable load impedance connected to terminals of the antenna, and a regulation loop regulating the voltage at terminals of the variable load impedance having rectifier means for rectifying the voltage at the terminals of the antenna and control means designed to modify the variable load impedance according to the output voltage of the rectifier means, and the station emitting an alternating magnetic field modulated in amplitude on 2N levels by data to be transmitted, encoded on N bits, the object having demodulation means having an n-bit analog to digital converter, clocked at an oversampling frequency much higher than the frequency of the data and connected between the rectifier means and the control means, and digital processing means connected to the output of the converter.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.