Patent ID: 7626547

Claim:
A planar patch antenna for connection to an electrically conductive feed line, said antenna having a plurality of areas and layers arranged one above the other along an axial axis, said patch antenna comprising: an electrically conductive ground plane; a first dielectric substrate layer, which is arranged on the ground plane, said first dielectric substrate layer having a first relative permittivity; at least one electrically conductive effective area which is arranged on the first dielectric substrate layer and is electrically connected to an end of the electrically conductive feed line; at least one second dielectric substrate layer arranged on the effective area and having a second relative permittivity, wherein the uppermost layer of the antenna does not consist of the electrically conductive effective area and/or the uppermost layer of the antenna comprises the at least one second dielectric substrate layer; the second relative permittivity being larger than or equal to the first relative permittivity, at least one recess provided in the at least one second dielectric substrate layer, said at least one recess extending in the at least one second dielectric substrate layer in an axial direction up to the at least one effective area, the at least one recess being located over the end of the electric feed line.