Method and system for the detection, by inductive coupling, of a load modulation signal
US6329808A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Jun 3, 1999 |
| Grant date | Dec 11, 2001 |
| Priority date | — |
| Expiry date | Jun 3, 2019 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04B5/73
- WIPO fieldTelecommunications
- WIPO sectorElectrical engineering
Abstract
A system for the detection of a load modulation signal by inductive coupling includes an antenna circuit having a coil, a circuit for applying an excitation signal having a predetermined frequency to the antenna circuit, and a current sensor for detecting a current signal in the coil. A phase comparator has a first input receiving the excitation signal, and has a second input receiving the current signal detected by the current sensor. The system also includes a circuit for extracting the load modulation signal from a phase signal provided by the phase comparator. The antenna circuit does not form a resonant circuit equal to or near the predetermined frequency of the excitation signal.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.