Antenna apparatus
First Claim
1. An antenna apparatus for use in a compact portable radio, said apparatus including a telescopic whip antenna corresponding to first and second frequency bands, said whip antenna being movable between a position extended from a body of said radio and a position accommodated in the body of said radio, comprising:
- a monopole antenna element connected to an antenna matching circuit via a first contact when said whip antenna is extended;
a helical antenna element connected to said antenna matching circuit via a second contact when said whip antenna is accommodated;
a parasitic helical element, said parasitic helical element being disposed a distance from said helical antenna element, said distance being smaller than a wavelength of said first frequency band, and wherein said parasitic helical element remains said distance from said helical antenna element as said whip antenna is moved between said extended and accommodated positions.
1 Assignment
0 Petitions
Accused Products
Abstract
In an antenna apparatus, a monopole antenna element connected to an antenna matching circuit via a first contact 105 when a whip antenna is extended; a helical antenna element connected to the antenna matching circuit via a second contact when the whip antenna is accommodated; and a parasitic helical element disposed in close proximity to the helical antenna element at a spacing which is sufficiently small with respect to the wavelength of a first frequency band of a radio circuit.
29 Citations
6 Claims
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1. An antenna apparatus for use in a compact portable radio, said apparatus including a telescopic whip antenna corresponding to first and second frequency bands, said whip antenna being movable between a position extended from a body of said radio and a position accommodated in the body of said radio, comprising:
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a monopole antenna element connected to an antenna matching circuit via a first contact when said whip antenna is extended; a helical antenna element connected to said antenna matching circuit via a second contact when said whip antenna is accommodated; a parasitic helical element, said parasitic helical element being disposed a distance from said helical antenna element, said distance being smaller than a wavelength of said first frequency band, and wherein said parasitic helical element remains said distance from said helical antenna element as said whip antenna is moved between said extended and accommodated positions. - View Dependent Claims (2, 3, 4, 5, 6)
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Specification