Patent ID: 8542149

Claim:
An antenna comprising: a conductor plate with an axisymmetrical shape; at least one slot formed on the conductor plate; and a feeding point provided on an axisymmetrical axis of the conductor plate, wherein: the conductor plate is folded along two locations which are parallel to the axisymmetrical axis toward mutually different directions; the at least one slot has an axisymmetrical shape and an axisymmetrical axis that matches the axisymmetrical axis of the conductor plate; the conductor plate has a horizontally rectangular shape oriented in the direction of the axisymmetrical axis; a composite slot is formed on one part of the axisymmetrical axis of the conductor plate, the composite slot comprising a laterally-facing M-shaped slot and a trapezoid slot with a width gradually becoming larger to an open end and formed in a succession of the laterally-facing M-shaped slot; and a rectangle slot is formed on the other part of the axisymmetrical axis of the conductor plate, thereby a slot boundary conductor portion being formed in the central portion on the axisymmetrical axis of the conductor plate between the composite slot and the rectangle slot.