Patent ID: 8717249

Claim:
A variable directivity antenna apparatus comprising: one feed element; and two parasitic elements provided to be aligned with each other, such that the feed element is interposed between the two parasitic elements and such that the two parasitic elements are electromagnetically close to the feed element, each parasitic element of the two parasitic elements having one end connected to one end of a respective diode having another end thereof grounded, wherein a directivity of the variable directivity antenna apparatus is changed by turning on and off the diodes connected to the two parasitic elements, wherein the feed element comprises: a first antenna element having a first width; a dual-band forming inductor; and a second antenna element having a second width wider than the first width, wherein the first antenna element, the dual-band forming inductor, and the second antenna element are connected in series with each other, wherein the dual-band forming inductor has a trapezoidal envelope external shape having an element width formed to widen starting from an element width identical with the first width at a portion of the dual-band forming inductor connected with the first antenna element and continuing to the second width of the second antenna element, and wherein each of the parasitic elements includes a cut portion having a rectangular shape, which is formed at a top corner portion thereof opposing to the dual-band forming inductor.