High-efficient compact antenna means for a personal telephone with a small receiving depth
AssigneeAllgon AB
InventorsUlf Saldell, Stefan Lofgren
Life of this patent
Estimating the term…
Abstract
An antenna to be mounted on a personal telephone. The antenna has a helical radiator, an elongated radiator extendable through the helical antenna, and a coupler for activating the extendable elongated radiator, when in extended position. A more compact antenna with less need for receiving depth inside the telephone, is achieved by permitting the extendable elongated radiator, when in a retracted position, to extend at least partially inside the helical radiator. In the extended position the elongated radiator may be coupled to the telephone directly or via the helical antenna.
Claims30
An antenna device for a radio communication device comprising:
- an essentially cylindrically configured radiator surrounded by dielectric material for minimizing coupling, said essentially cylindrically configured radiator mounted on and coupled to said radio communication device;
- an extendable elongated radiator movable to an extended position and to a retracted position;
- a switching device for coupling said extendable elongated radiator, when in said extended position, to said radio communication device;
- said essentially cylindrically configured radiator having an opening, and said opening extending axially through said essentially cylindrically configured radiator;
- said extendable elongated radiator being movably mounted through said opening of said essentially cylindrically configured helical radiator;
- wherein
- said extendable elongated radiator, when in the retracted position, extends inside said essentially cylindrically configured radiator in order to reduce a total length of said antenna device, and at least one of the properties length, geometry and surrounding dielectric material of said essentially cylindrically configured radiator is selected so as to obtain a compensating capacitive/inductive load on the essentially cylindrically configured radiator at least partially compensating a first capacitive/inductive load on the essentially cylindrically configured radiator resulting from the presence of the elongated radiator inside said essentially cylindrically configured radiator in the retracted position.
An antenna device for a radio communication device comprising:
- an essentially cylindrically configured radiator surrounded by dielectric material for minimizing coupling, said essentially cylindrically configured radiator mounted on and coupled to said radio communication device;
- an extendable elongated radiator movable to an extended position and to a retracted position;
- a switching device for coupling said extendable elongated radiator, when in said extended position, to said radio communication device;
- said essentially cylindrically configured radiator having an opening, and said opening extending axially through said essentially cylindrically configured radiator;
- said extendable elongated radiator being movably mounted through said opening of said essentially cylindrically configured helical radiator;
- wherein
- said extendable elongated radiator, when in the retracted position, extends inside said essentially cylindrically configured radiator in order to reduce a total length of said antenna device, which extension defines a penetration depth, and at least one of the properties length, geometry and surrounding dielectric material of said essentially cylindrically configured radiator and penetration depth of the extendable elongated radiator is selected so as to obtain a compensating capacitive/inductive load on the essentially cylindrically configured radiator at least partially compensating a first capacitive/inductive load on the essentially cylindrically configured radiator resulting from the presence of the elongated radiator inside said essentially cylindrically configured radiator in the retracted position.
Dependencies are inferred from the claim text.