Antenna device and door handle device
US7679571B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Sep 16, 2005 |
| Grant date | Mar 16, 2010 |
| Priority date | — |
| Expiry date | Nov 6, 2025 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG07C2209/65
- WIPO fieldTelecommunications
- WIPO sectorElectrical engineering
Abstract
A transmission/reception antenna (21) comprises a core (31) and a coil (32) wound around the core (31). One of a plurality of core sheets (31a) constituting the core (31) is utilized as a sensor electrode (23). Conductors (33, 34) extending from the two ends of the coil (32) are connected to a transmission/reception drive circuit (22). The conductor (35) extending from a capacitance detector (24) is connected to one of the conductors (33, 34) extending between the coil (32) and the transmission/reception drive circuit (22). Consequently, the capacitance detector (24) is alternately connected to the sensor electrode (23) through a parasitic capacitance C1 generated between the coil (32) and the sensor electrode (23) (core sheet (31a)).
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.