Adapter antenna
First Claim
1. An adapter for contact-less transfer of electromagnetic waves between a first antenna built into a mobile telephone and a port of the adapter antenna where a coaxial cable can be connected, the adapter antenna comprising a condenser plate, a conductor connecting the condenser plate with the port and adaptive components including ground plane elements, said first antenna transferring without contact the electromagnetic wave to the adapter and said adapter antenna transferring the electromagnetic wave without contact back to said first antenna by utilizing an electric component of a near field of the first antenna and by shaping the condenser plate surface to correspond as far as possible to those regions of a surface of the first antenna carrying large surface currents, and by having optimal shape and size of the components of the adapting circuit to minimize influence on the matching of the first antenna to telephone electronics.
1 Assignment
0 Petitions
Accused Products
Abstract
An adapter antenna (2) is used for contactless connection of a mobile telephone (1) to an external antenna (4) in case the telephone lacks a connector for coaxial cable (3) for such a purpose. The most common application is when a mobile telephone is to be used in a vehicle. Transfer of radio waves occurs in the near field of the built-in antenna (6) of the telephone by capacitive coupling. One preferred embodiment especially suited for plane inverted antennae of type L, E or F is described. An optimizing method for two frequency bands is described.
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Citations
11 Claims
- 1. An adapter for contact-less transfer of electromagnetic waves between a first antenna built into a mobile telephone and a port of the adapter antenna where a coaxial cable can be connected, the adapter antenna comprising a condenser plate, a conductor connecting the condenser plate with the port and adaptive components including ground plane elements, said first antenna transferring without contact the electromagnetic wave to the adapter and said adapter antenna transferring the electromagnetic wave without contact back to said first antenna by utilizing an electric component of a near field of the first antenna and by shaping the condenser plate surface to correspond as far as possible to those regions of a surface of the first antenna carrying large surface currents, and by having optimal shape and size of the components of the adapting circuit to minimize influence on the matching of the first antenna to telephone electronics.
Specification