Abstract: A patch antenna having a dielectric substrate; a plurality of radiating patches on the substrate, each radiating patch including a plurality of spaced slots to suppress the radiation of energy that is polarized in a direction transverse to the direction of the desired polarization; a ground plane supported by the substrate in generally parallel and spaced relationship to the patches; a distribution network for transmitting and receiving signals within the antenna; and a plurality of probes within the substrate for coupling the radiating patches and the distribution network, one end of each probe being connected to the distribution network, and the other end of the probe being coupled to one of the radiating patches. In a preferred embodiment, a plurality of chokes are connected to the ground plane and associated with the patches to further suppress the radiation of energy having undesired polarization.

Abstract: A collapsible bifilar helical antenna comprises a rigid mast, a pair of flexible helical conductors wound about the mast, and a plurality of support arms spaced along the mast and extending radially outwardly therefrom for supporting the helical conductors, the support arms being movable along the axis of the mast to permit the helixes formed by the conductors to be expanded and contracted. The mast includes multiple sections which permit adjustment of the axial length of the mast. The support arms are mounted on sleeves which are slidable along the mast, each of the support arms has a tubular member mounted on the outer end thereof, and each of the flexible helical conductors comprises a metal cable which passes through the interiors of the tubular members.

Abstract: A rigid coaxial transmission line in which the inner conductor is formed by axially spaced sections. Adjacent sections are connected by a conductive bellows which permits thermal expansion and contraction of the inner conductor sections relative to one another and relative to the outer conductor of the transmission line. A rigid auxiliary connecting member is disposed within the bellows and is slidably connected to one of the conductor sections. The auxiliary connecting member limits expansion and contraction of the bellows to a safe range to prevent the bellows from being overstressed.