Antenna impedance matching network requiring no switch contacts
US5874921A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Sep 20, 1996 |
| Grant date | Feb 23, 1999 |
| Priority date | — |
| Expiry date | Sep 20, 2016 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01Q1/244
- WIPO fieldTelecommunications
- WIPO sectorElectrical engineering
Abstract
An apparatus for providing an antenna impedance matching network that does not include mechanical switch contacts is disclosed. A retractable antenna includes a conductive plate moveable between the extended and retracted positions of the antenna. When the conductive plate is located in the extended position an impedance matching circuit responsive to the position of the conductive plate is connected between the antenna and an amplifier of a radio telephone. In response to location of the conductive plate in the retracted position, the impedance matching circuit is shorted out such that the antenna is connected directly to the amplifier via a capacitive effect between the conductive plate and a conductive coil of the shorted out impedance matching circuit.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.