Patent attributes
An unbalanced antenna having a radiation conductor and a ground conductor provided with a predetermined gap therebetween is provided. At least a predetermined part of the ground conductor, the predetermined part being opposed to the radiation conductor, is left so that it keeps functioning as a pole for forming a near electromagnetic-field distribution together with the radiation conductor opposed to the ground conductor. Further, a part of the reduced ground conductor, the part being near an end at a predetermined distance from the feed section, includes a conductor having low conductivity for obtaining impedance matching. Where the ground conductor is significantly reduced, mode mismatch inevitably occurs. Therefore, at least one part of an external conductor of a coaxial feed line connected to the feed section is covered by a current absorber, so as to forcefully reduce a leakage current. Subsequently, the ground conductor can be reduced and the antenna characteristic can be maintained.
