Abstract: A two-arm delta mode spiral antenna includes a dielectric substrate having an upper side, a lower side, and an outward edge. A flat top cone with cylinder sidewall is attached to the lower side of the dielectric substrate, forming a scalable feed cavity. Two spiraling conductive radiator arms are mounted on the dielectric substrate. A magic-T is electrically connected to the two spiraling conductive radiator arms.

Abstract: A minimum depth spiral antenna includes a fiberglass circuit board with two spiraling conductive radiator arms that are etched on the fiberglass circuit board. A metallic ring is formed around the two spiraling conductive radiator arms and is mounted on the outward edge of the fiberglass circuit board. An antenna cavity cone and antenna cavity cone cap are mounted inside the antenna cavity. A tapered microstrip balun circuit is electrically-connected to the two spiraling conductive radiator arms on its proximal end and to a connector cap on its distal end. The connector cap is mounted on the lower side of a bottom plate, which forms the base of the antenna. The antenna cavity cone has a bottom lip. A wall ring is positioned between the bottom plate and the metallic ring. The wall ring connects the bottom plate to the metallic ring.

Abstract: A dual polarized broadband, lightweight, low cost tapered slot antenna which has first and second radiating tapered slot antennas which are co-located and positioned perpendicular to one another. Each antenna includes a relatively thin dielectric substrate and a radiating metallic antenna element mounted on the upper surface of the dielectric substrate. A tapered notch area, which is centrally located, is etched away to expose the dielectric substrate. The tapered slot antennas allow for linear polarization, elliptical polarization and circular polarization.

Abstract: A spiral antenna having a pair of antenna arms mounted on a dielectric substrate. A balun is included to connect the antenna which has an impedance of 100 ohms to a 50 ohm cable. Unique features of the spiral antenna design provide for size reduction at a given lowest required frequency of operation. The spiral antenna has dielectric material layers positioned on both side of the antenna's metal arms. In addition, the antenna input impedance is reduced from the normal 100 ohm input impedance to approximately 50 ohms due the dielectric material.

Abstract: In a preferred embodiment, a spiral or helical antenna offering expanded operation at low frequencies while retaining a package size roughly equivalent to an unmodified antenna having a bandwidth not extended in low frequency. A preferred embodiment is a planar spiral antenna incorporating a pair of spiral arms, one arm of which has been modified to incorporate a capacitance at selected intervals along upper and lower surfaces of that arm so as to cause a phase shift in one of the input signals to the antenna. The input signal is provided by splitting at a balun a single signal into two equal amplitude signals 180° out of phase with each other. The subsequent phase shift permits the two out of phase input signals to be brought back into phase at calculated intervals prior to termination of the signals at the arms' ends.

Abstract: A dielectric constant measurement probe assembly includes a coaxial cable ving a outer electrical conductor and a center electrical conductor extending within the outer conductor and terminating at an end portion which projects beyond an end portion of the outer conductor. An adapter member has a central passage receiving the coaxial cable with the outer conductor of the cable extending through the passage of the adapter member and projecting therefrom. An outer tube has a bore composed of first and second axial sections. The second bore section is smaller in diameter than the first bore section. The adapter member is inserted in the first bore section with the end portion of the coaxial cable outer conductor inserted into the second bore section and making electrical contact therewith such that the outer tube thus constitutes an extension of the outer conductor.