Patent ID: 7193576

Claim:
A slot antenna comprising: an insulation substrate; a metal layer on the insulation substrate; and a feeding part connected to the metal layer, wherein the metal layer has a slot, the slot is symmetric with respect to a centerline, when an x-y coordinate system is defined on the metal layer so that the y-axis is the centerline, the origin is the center of the slot antenna, and the x-axis through the origin is perpendicular to the y-axis, the width of a first portion of the slot in the direction of the y-axis is gradually enlarged in proportion to the absolute value of the x-axis, and an extension part extends on the centerline from a side of the slot antenna through the center of the slot antenna, the metal layer of the slot antenna is formed on a front side of the insulation substrate, the feeding part is formed on a back side of the insulation substrate, the insulation substrate has a hole from the front side to the back side, an electric conducting layer is formed on the inner surface of the hole or an electric conductive pin is inserted in the hole, and the feeding part is connected to the metal layer by the electric conductiing layer or by the electric conductive pin.