US 9,812,769 B2
Antenna apparatus
Yohei Koga, Kawasaki (JP); and Hiroyuki Egawa, Fukuoka (JP)
Assigned to FUJITSU LIMITED, Kawasaki (JP)
Filed by FUJITSU LIMITED, Kawasaki-shi, Kanagawa (JP)
Filed on Jun. 22, 2016, as Appl. No. 15/189,436.
Claims priority of application No. 2015-148145 (JP), filed on Jul. 27, 2015.
Prior Publication US 2017/0033453 A1, Feb. 2, 2017
Int. Cl. H01Q 1/38 (2006.01); H01Q 1/48 (2006.01); H01Q 1/24 (2006.01); H01Q 9/42 (2006.01); H01Q 5/371 (2015.01); H01Q 5/328 (2015.01)
CPC H01Q 1/48 (2013.01) [H01Q 1/243 (2013.01); H01Q 5/328 (2015.01); H01Q 5/371 (2015.01); H01Q 9/42 (2013.01)] 8 Claims
OG exemplary drawing
 
1. An antenna apparatus comprising:
a first ground plane having an end-side;
a second ground plane having
a first side disposed along the end-side, the first side having a first end and a second end,
a second side and a third side extending from the first end and the second end, respectively, in a direction away from the end-side in plan view,
a fourth side connecting the second side and the third side, and
a cutout part having a rectangular shape provided along the fourth side between the third side and a fifth side located between the second side and the third side, the second ground plane being cutout in the cutout part,
wherein the second end is connected to the first ground plane, and the second ground plane and the first ground plane form a slit between the second ground plane and the first ground plane in plan view, the slit having an open end located on aside of the first end;
a first radiating element having
a first line standing from a ground end with respect to the second ground plane, the first line being connected to the second ground plane in a vicinity of the first end of the first side,
a second line connected to the first line, the second line extending toward the third side along the fourth side to an end part, the end part located opposite to the ground end, and
a feeding point disposed at the end part of the second line;
a second radiating element having
a third line connected to the end part of the first radiating element, the third line extending along the fourth side toward the third side, and
a fourth line connected to the third line, the fourth line extending along the third side in a direction away from the first ground plane in plan view; and
a parasitic element having
a first parasitic line extending from the second end along the third side within the rectangular area, and
a second parasitic line connected to the first parasitic line, the second parasitic line extending toward the second side along the fourth side within the rectangular area,
wherein a length from the feeding point, via the first radiating element, the ground end, the second end, and the end-side to the open end of the slit is set to a one-half wavelength long at a first communication frequency,
wherein a total length of a length from an end part of the fourth line of the second radiating element to the feeding point, and a length from a ground potential point of the second ground plane corresponding to the feeding point to an end part of the second parasitic line of the parasitic element is set to a one-half wavelength long at a second communication frequency higher than the first communication frequency, and
wherein a length of the third line and the fourth line of the second radiating element is set to a one-quarter wavelength long at a third communication frequency higher than the second communication frequency.