Modulation and demodulation circuit
US8115538B2 · kind B2 · utility
Assignee
Inventor
Key dates
| Filing date | Jul 10, 2009 |
| Grant date | Feb 14, 2012 |
| Priority date | — |
| Expiry date | Sep 8, 2029 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH03D2200/0011
- WIPO fieldBasic communication processes
- WIPO sectorElectrical engineering
Abstract
The invention relates to the field of modulation and demodulation circuits, such as envelope detectors used to demodulate amplitude-modulated (AM) signals. By coupling an analog circuit to a port of a digital component, an envelope detector can be obtained, which achieves demodulation of AM signals for direct coupling into a digital input port. Accordingly, an envelope detector may be used in the data receiving part of a sealed device requiring post-manufacturing data transfer, in combination with additional components that provide electromagnetic coupling, such as inductive coupling, capacitive coupling, or radiative coupling. An example of such a device is a credit card sized authentication token.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.