RF transponder system with parallel resonant interrogation series resonant response
US5608417A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | May 16, 1996 |
| Grant date | Mar 4, 1997 |
| Priority date | — |
| Expiry date | May 16, 2016 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01Q7/00
- WIPO fieldComputer technology
- WIPO sectorElectrical engineering
Abstract
A transponder system employs a transponder antenna with a distributed inductance and capacitance that exhibit parallel and series resonant frequencies. Transmissions to the transponder circuit are made at one or more parallel resonant frequencies to maximize the excitation of the transponder circuit, while return signals transmitted back from the transponder are modulated at one or more series resonant frequencies to maximize the signal current. The transponder antenna is implemented as a pair of aligned coils on opposite sides of a thin dielectric substrate, with the coils connected together through the substrate at one point and the substrate thickness not more than about 25 microns to obtain a significant mutual inductance between the coils.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.