Multifrequency antenna for instrument with small volume
US6642895B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Sep 9, 2002 |
| Grant date | Nov 4, 2003 |
| Priority date | — |
| Expiry date | Sep 9, 2022 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01Q5/321
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
The antenna (1) is formed of a first strip element (3) the length (L1) of which is tuned to a high frequency (fh) and at least a second strip (4), following the first (4), of length (L2). The sum of the lengths L1 and L2 results in an antenna whose length L3 is tuned to a low frequency (fb). A resonant circuit (5) including an inductor (6), connected in parallel to a capacitor (7) is located between the first and second strips (3, 4). The values of these components are chosen so that the resonant circuit resonates at the high frequency (fh). When the high frequency is active, the length of the antenna is reduced to that (L1) of the first strip. When the low frequency is active, the length of the antenna extends to the sum (L3) of the lengths of the first and second strips. The inductor (6) is a substantially rectilinear band integrally formed with at least one (3) of said strips and connected to said strip by one (8) of its ends.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.