Patent ID: 6853344

Claim:
A radial line slot antenna, comprising: an antenna disk which has a slot element for transmitting/receiving electromagnetic waves on the front side and has a feeder section at the center of the rear side which is the opposite side of the front side; and a feeder disk where said antenna disk is mounted contacting the rear side thereof, and a feeder section for transmitting/receiving electromagnetic wave signals to/from said antenna disk is disposed, wherein when the diameter of said antenna disk is D and the wavelength of the central frequency is λ, a marker with a maximum size of about 0.10λ or less is disposed at an area or distance of about 0.5 (D−λ) to 0.5 D from the center on the rear side of said antenna disk, and said feeder disk further comprises a through hole with a size sufficient to view said marker at a position the same as the position of said marker, and said marker is a marker for positioning the antenna disk on said feeder disk after confirming that said marker is positioned at the center of said through hole.