Patent ID: 6940457

Claim:
A multifrequency antenna comprising: a plurality of nonconducting substantially planar substrates, with a conductive layer disposed on a surface of each planar substrate of the plurality of nonconducting substantially planar substrates; a first substrate of the plurality of nonconducting substantially planar substrates, having a transmission line disposed on a rear surface of the first substrate, and having a first conducting layer disposed on a other surface of the first substrate, with the first conducting layer including a plurality of slotted openings arrayed about an antenna axis; a second substrate of the plurality of nonconducting substantially planar substrates, stacked on the first substrate, and having a second conducting layer disposed on a surface of the second substrate, with the second conducting layer including a multiplicity of slotted openings arrayed about an antenna axis; a third substrate of the plurality of nonconducting substantially planar substrates, stacked on the second substrate, and having a third conducting layer disposed on a surface of the third substrate; a lossy-dielectric-magnetic material for enclosing sides and rear of the multifrequency antenna, for preventing electromagnetic energy penetration through the rear and sides of the multifrequency antenna, with the multifrequency antenna thereby radiating and receiving electromagnetic energy from a front of the multifrequency antenna; and an edge-diffraction reflector attached to rear of the multifrequency antenna, including at least two conducting plates and a plurality of conducting cylinders with height essentially shorter than a diameter along an axis of the multifrequency antenna.