Patent attributes
In an antenna device, a radiation slot formed in a metal plate includes a main slot part on one diagonal line of the metal plate and first and second branch slot parts. The first and second branch split parts extend along two adjacent sides of the metal plate and are connected to one end of the main slot part. A power feeder line and a ground line are formed in the vicinity of another end of the main slot part. The length and relative position of each slot part is set such that the plane of polarization of an electric wave radiated from the main and first slot parts and the plane of polarization of an electric wave radiated from the main and second slot parts are orthogonal to each other and the two electric waves differ in phase by 90 degrees.
