Abstract: A VHF/UHF communications blade type antenna additionally having microwave nding system (MLS) antenna elements mounted thereon and having the microwave feed components integral therewith to provide a composite structure adapted to function both as a communications and as a navigation antenna. The antenna is particularly adapted for use with aircraft which is to be retrofitted to include MLS capability.

Abstract: A dielectric loaded edge-slot radiator whose exterior dimensions are adjuble to allow flush mounting on cylindrical and conical bodies which can be frequency tuned either electrically or mechanically. This is done by varying the number of inductive posts which are used as boundaries for the individual elements making up the antenna. A single inductive probe whose characteristic impedance is matched to the rf source is coupled so as to simultaneously excite all of the radiating elements in phase. The radiation field produced in a plane containing the radiator is nearly of constant amplitude.

Abstract: In a projectile or rocket having a metal outer shell and including a proximity or influence detonator which operates with electromagnetic waves, particularly according to the reflected beam principle, and a directional antenna with a rotationally symmetrical radiation diagram for said detonator, the antenna is constituted by a circular slot which is coaxial with the longitudinal axis of the projectile or rocket and the antenna is excited with a line or cavity resonator disposed in the projectile or rocket and connected between the detonator and the antenna.

Abstract: A very small vertically and horizontally polarized antenna having direction finding capabilities at low microwave frequencies employs filamentary vertically polarized antenna elements and resistively loaded slots for horizontally polarized radiation with a pair of the antennas being employed for direction finding.

Abstract: A radome-integrated conformal parallel plate radiator for a projectile. An ntenna system consisting of open-ended dielectric load cavity radiators is incorporated into a dielectric radome structure for space conservation and operational versatility. A plurality of individual radiating elements, preferably in the form of wedge-shaped metallic radiators, are flush-mounted on the non-planar surface of a projectile's radome. The interior surface of the hollow radome includes either a solid conductive ground plane deposited thereon or a wire screen mesh ground plane which is transparent to certain frequencies. Each of the exterior mounted wedge-shaped radiators are short-circuited to the ground plane, and may be individually excited and controlled to produce a desired radiation pattern.

Abstract: A low-profile UHF antenna comprises two orthogonally positioned parallel te radiators that are semi-circular in shape. The base of each radiator (filled with dielectric material) is connected to a circular metal ground plane. The radiators can be collectively excited with a single input feed or they can be independently excited in any phase relationship for changing direction or polarization of the radiation field. Thus, the antenna is capable of operating in either a linear or circular polarization mode. The antenna can also be switched rapidly from one linear polarization to a second linear polarization in a perpendicular plane by using techniques familiar to the art.

Abstract: A double omni-directional antenna for use with a transponder is disclosed allowing simultaneous operation within two different frequency bands. A double coaxial line is provided having outer, central, and inner concentric conductors. The outer and central conductors form a coaxial feed for a lower frequency antenna and the central and inner connectors form a coaxial feed for a high frequency antenna. The higher frequency antenna is located directly above the lower frequency antenna and each is either a unipole for vertically polarized radiation or a slot radiator for horizontally polarized radiation.

Abstract: Disclosed herein is an antenna system for use with small projectile nose es (metal). The antenna comprises a wedge shaped metallized dielectric material having an electrical length equal to one-quarter wavelength as measured inside the center line of the wedge. The metallic coating covering both the top and bottom of the wedge is provided to form a parallel plate radiator. The metallic coating is also extended across the base of the wedge to define an RF short circuit at the base and an open circuit at the apex. An RF coupling probe extending into the wedge is located at a convenient impedance matching point near the base of the wedge. The operating frequency of the antenna may be capacitively tuned (either electrically or mechanically) by means of a variable capacitor connected across the open circuit end (the apex) of the antenna. Typically the dielectric comprises teflon-fiberglass or ceramic material although an air dielectric is also usable.

Abstract: An inductive, internally fed, ferrite-loaded antenna mounted at the geomecal center of a helicopter. The antenna is capable of transmitting in the 2-30 MHZ range with particularly good characteristics between 2.0-3.5 MHZ and employs the air frame as a radiating element. The radiation pattern is circular and extends for a radius greater than 200 mi. at an altitude of 300 feet.

Abstract: A dual slot antenna assembly is disclosed herein and generally includes a pair of concentrically positioned and radially spaced cylindrical conductors defining a pair of circumferential slots which are longitudinally spaced one-half wavelength apart at the anticipated operating frequency of the antenna device. An electrical signal feed assembly is connected with the conductors for exciting the slots so as to provide overlapping radiation patterns emanating in the same direction.