Patent ID: 9746555
Date: 2017-08-29
CPC Classifications: G01S,H01Q

Claim:
1. A planar antenna comprising: a dielectric substrate; an antenna main body portion including a first antenna element provided on a first side of the dielectric substrate and a second antenna element provided on a second side of the dielectric substrate, the first antenna element and the second antenna element functioning as a balanced antenna; a signal line portion including a first feed line provided on the first side and connected to a feed point of the first antenna element for feeding power to the first antenna element, a second feed line on the second side and connected to a feed point of the second antenna element for feeding power to the second antenna element, and a signal line provided on the first side and connected to the first feed line, the first feed line and the second feed line forming a pair of feed lines provided at identical locations with the dielectric substrate sandwiched therebetween; first ground conductors provided on the first side to sandwich the signal line with spacing therebetween, the first ground conductors forming a coplanar line with the signal line; a second ground conductor provided in an identical region of the second side of the dielectric substrate to a region of the first side where the coplanar line is present, with the dielectric substrate sandwiched therebetween, the second ground conductor being connected to the second feed line; and via holes connecting the first ground conductors to the second ground conductor provided at ends of edges of the first ground conductors facing the end of the signal line where the signal line is connected to the first feed line, to allow the first feed line and the second feed line function as balanced transmission lines.