Patent ID: 8279121
Filing Date: 2012-10-02
Classification: H01Q

Abstract:
1. An antenna device comprising: a plurality of antenna units each including an independent power feeder and a respective radiation electrode; a circuit board including an antenna mounting area on which the plurality of antenna units are mounted; and a dielectric base on which at least one of the respective radiation electrodes of the plurality of antenna units is provided; wherein of the plurality of antenna units, a first antenna unit having a lowest fundamental frequency is disposed at an end of the antenna mounting area; a second antenna unit having a highest fundamental frequency of the plurality of antenna units is disposed at a greater distance from the first antenna unit than a distance by which another one or more of the plurality of antenna units are separated from the first antenna unit; the another one or more of the plurality of antenna units are interposed between the first and second antenna units and in parallel therewith; in the first antenna unit, a current-density control circuit capable of controlling a current density in the respective radiation electrode is interposed between the respective radiation electrode and the independent power feeder, and a reactance circuit arranged to adjust a frequency by varying an electrical length of the respective radiation electrode of the first antenna unit is disposed in a middle portion of the respective radiation electrode; a recess is provided on a surface of the dielectric base; and a substrate on which the reactance circuit is provided is disposed inside the recess.