Reader or transmitter and/or receiver comprising a shielded antenna
US7098866B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Oct 31, 2002 |
| Grant date | Aug 29, 2006 |
| Priority date | — |
| Expiry date | Oct 31, 2022 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01Q7/04
- WIPO fieldTelecommunications
- WIPO sectorElectrical engineering
Abstract
The reader or transmitter and/or receiver (22) includes a sheathed antenna formed of two groups of turns or coils (6, 8, 9; 16, 17). The first group of turns or coils forms a sheathed antenna. The second group includes two coils (16, 17) arranged between the central coil (6) and respectively the two end coils (8, 9) of the first group. The second group of coils is powered in phase quadrature relative to the first group of coils, the set of coils being arranged so as to obtain a magnetic field (H) whose amplitude (A) is approximately constant along the central axis (24) of the antenna inside the overall inner volume of the latter.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.