Electronic devices with parasitic antenna resonating elements that reduce near field radiation
US8466839B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Dec 7, 2009 |
| Grant date | Jun 18, 2013 |
| Priority date | — |
| Expiry date | Apr 2, 2031 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01Q1/44
- WIPO fieldTelecommunications
- WIPO sectorElectrical engineering
Abstract
Antennas are provided for electronic devices such as portable computers. An electronic device may have a housing in which an antenna is mounted. The housing may be formed of conductive materials. A dielectric antenna window may be mounted in the housing to allow radio-frequency signals to be transmitted from the antenna and to allow the antenna to receive radio-frequency signals. Near-field radiation limits may be satisfied by reducing transmit power when an external object is detected in the vicinity of the dielectric antenna window and the antenna. A proximity sensor may be used in detecting external objects. A parasitic antenna resonating element may be interposed between the antenna resonating element and the dielectric antenna window to minimize near-field radiation hotspots. The parasitic antenna resonating element may be formed using a capacitor electrode for the proximity sensor. A ferrite layer may be interposed between the parasitic element and the antenna window.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.