Patent ID: 8174459

Claim:
A coplanar antenna unit, comprising: a substrate; a radiation plane disposed on a first side of the substrate, and comprising: a feed plane receiving a feed-in signal, and the feed-in signal generating a radiation signal at the feed plane; and an output plane having an interval from the feed plane, and the radiation signal being coupled to the output plane, and the output plane outputting the radiation signal, and the output plane including a first extension portion and a second extension portion; a first ground plane disposed on the first side of the substrate, and situated on a first side of the radiation plane, and the first ground plane having a first hollow portion, and the first extension portion being disposed in the first hollow portion, and an end of the first extension portion being coupled to the first ground plane; a second ground plane disposed on the first side of the substrate, and situated on a second side of the radiation plane, and the second ground plane having a second hollow portion disposed at a position corresponding to the first hollow portion, and the second extension portion being disposed in the second hollow portion, and an end of the second extension portion being coupled to the second ground plane; and a metal plate disposed on a second side of the substrate, and the metal plate being disposed corresponding to the radiation plane.