Abstract: A Tee slot blade antenna for aircraft and other high speed vehicles has a pair of dielectric sections, one section extending longitudinally along the blade and the other extending transversely from an intermediate location along the longitudinal section. The resonant frequency of the antenna is determined by the length of each section and the position of the transverse section along the longitudinal one, while the characteristic impedance is a function of the width of each section. The Tee slot antenna is capable of operating over a wide bandwidth on a smaller blade than prior single slot antennas. A Tee slot antenna designed for one frequency range can be combined with either a single slot antenna or another Tee slot antenna designed for another frequency range on the same antenna blade, without impairing the bandwidth of either antenna.

Abstract: The invention comprises an antenna capable of effective operation at a number of different frequencies, not necessarily harmonically related, that may be separated in frequency by as little as twenty-five percent. The elements of the antenna are decoupled by loaded coaxial chokes that form part of the active portion of the antenna at the resonant frequency of the chokes. The chokes are loaded with a solid dielectric insert dimensioned so that the inner surface of the shell of the choke and the outer surface of the conductor extending through the choke form a quarter wave shorted transmission line to produce an infinite impedance at the open end of the choke. The chokes may be arranged in series, parallel or series-parallel configurations.

Abstract: A space fed antenna with a folded path to reduce the distance between a phased array and the focal point of such array is shown to be made up of: (a) a first plurality of vertically polarized antenna elements incorporated in the phased array; (b) a second plurality of cross-polarized antenna elements disposed to form a polarization-twisting screen at a distance from the first plurality of vertically polarized antenna elements equal to one-third the focal length of such elements; and (c) a third plurality of latching circulators connected between selected pairs of cross-polarized antenna elements in the polarization-twisting screen so that such pairs also may function as a feed array for the space fed antenna.

Abstract: A plurality of plates are rigidly affixed normal to forward and rearward surfaces along a major axis of a maximal diameter of an asymmetrical rotating antenna. In the presence of a wind, any aerodynamic forces tending to produce aerodynamic rotational moments on the antenna are reduced by the interaction between the wind, which produces a boundary layer on the antenna, and the plates, which affect the boundary layer.The net effects of the plates are to reduce the aerodynamic pressure difference between the forward and rearward surfaces of the antenna and to move the center of aerodynamic pressure closer to the center of rotation of the antenna. Due to these effects, the overall aerodynamic rotational movement on the antenna is reduced.

Abstract: An antenna array comprises a dielectric image waveguide (3) acting as a feeder, which may be of the insular or inverted-strip type, in contact with a dielectric sheet (1). On the sheet (1) is located a plurality of strips (4) of metallizing extending outwards from the feeder-guide (3). The inner ends of the strips are located to couple with the feeder-guide and their outer ends act to radiate or receive most of the power. Preferably the mode propagated in the feeder-guide is an E.sub.mn.sup.y mode higher than the fundamental, suitably the E.sub.21.sup.y mode.

Abstract: A scannable antenna having a radiating array of antenna elements correspondingly coupled, through equal line lengths, to a more closely spaced array of antenna elements positioned in a space coupling region. A feed array of antenna elements, with spacings substantially equal to the spacing in the radiating array and substantially of the same physical size as the more closely spaced array, is positioned in the space coupling region in close proximity, no more than a wave length away, to the more closely spaced array. The feed array is coupled to a distribution network which provides desired phase and amplitude aperture distributions.

Abstract: A primary source for a space communications antenna requiring a mode extractor means comprises more especially a horn with two types of evenly spaced alternate corrugations whose depth decreases, for each of the types, from the neck to the opening, followed by a band separator of the quasi-optical filter type, followed by a mode extractor means placed in series in the reception channel of the primary source.

Abstract: A portable antenna is disclosed herein having a pedestal supporting on octagon frame via a universal mounting mechanism. A parabolic reflecting antenna is fixed onto a plurality of mounting sockets on the frame and includes a plurality of individual and separate wedge-shaped panels adapted to be assembled in a side-by-side relationship to provide a unitary construction. Each panel includes outwardly projecting flanges on its oppsite edge marginal regions cooperating with similar flanges on adjacent panels to define a combined mounting flange to be insertably aligned with and received into the mounting sockets carried on the frame. Fasteners secure the flanges and sockets together in a fixed relationship.

Abstract: In a reflecting mirror antenna unit, the surface of the reflecting mirror is divided into a plurality of parts, and the parts are made different in thickness from one another, for instance, by bonding metal tapes different in thickness thereto, to change the phase distribution on the reflecting mirror, whereby the configuration of the radiation pattern due to the current distribution on the reflecting mirror is readily changed.

Abstract: An improved rain resistance radome C-sandwich wall is constructed of thermoplastic polycarbonate material. The cores are either posts or tubes and are bonded to the skins with polyurethane. The percentage of core material to air is adjusted by electrical tuning to make the optimum dielectric value for use in the gigahertz radar frequency range.

Abstract: An antenna for a vehicle-mounted receiver/transmitter includes: a driver for extending and retracting an antenna connected to the receiver/transmitter; a selector for selecting a frequency to be received and/or transmitted by the receiver/transmitter; and a controller which operates in response to an output from the frequency selector for causing the driver to extend and retract the antenna by the length corresponding to the frequency, and for retracting almost the entire antenna into the body of the vehicle when the receiver/transmitter is not operating.

Abstract: An antenna is disclosed that is especially useful for radiating and receiving non-sinusoidal electromagnetic waves. The antenna is an efficient and distortion-free radiator of electromagnetic pulses that do not use a sinusoidal carrier. The antenna's size is independent of frequency and the antenna, therefore, can be of small size relative to the wavelength of the radiated electromagnetic waves. When used for reception of electromagnetic wave energy, the antenna performs with low distortion. The basic concept underlying the invention is the modification of the Hertzian electric dipole into an antenna structure that can carry large currents without requiring a large driving voltage. Antennas for the transmission or reception of sinusoidal waves achieve that goal by employing resonant structures.

Abstract: A log-periodic antenna comprises two arrays of dimensionally tapered radiating elements disposed in the E-plane and each fed by a balanced line consisting of the inner conductors of two coaxial cables. In one embodiment the elements of each array are dipoles and in another embodiment are formed of continuous conductive strips in zig-zag patterns on non-conductive support members. Each array preferably have two sets of elements disposed in planes, respectively, which converge toward the smaller end of the array with vertically aligned radiating elements of each set projecting in opposite directions from the array axis. Periodic gain dropout anomalies across the antenna operating band are eliminated by use of a shielded feed line.

Abstract: A flat face annular grooved metal surface surrounds a circular waveguide opening coupled to a small dipole radiator which excites the circular waveguide in its fundamental propagating mode (TE.sub.11). The dipole is arranged to rotate about its axis by means of an extension of its inner conductor, which forms a simple probe in a section of rectangular waveguide situated behind the circular waveguide. A dielectric shaft is fastened to the inner conductor and is brought to the outside of the rectangular waveguide where it is connected to a small motor. The motor is arranged so that it may be actuated remotely by any of several circuits. The dipole may be before the corrugated plate with bent arms. A pair of dipoles may be arranged perpendicular to each other with two separate coaxial connector antenna feed outputs for direct attachment to coaxial-type low-noise amplifiers.

Abstract: A coaxial dipole antenna includes a first radiator which is approximately one quarter wavelength long. A second radiator exhibits length less than one quarter wave length and is coupled to the feed port by a reactive element which has an electrical reactance which is insufficient to increase the electrical length of the second radiator to one quarter of the wavelength. The length of a dipole antenna is substantially shortened while an effective aperture of one half wavelength is maintained by causing a portion of the transceiver housing to radiate in phase with the antenna.

Abstract: A feed element-to-beam interconnection network is provided for an antenna that transmits and receives a large number of beams, such as 87 contiguous narrow beams that cover the United States. The network, which is connected to a layer of 134 feed elements that transmit and receive microwaves, consists of a pair of circuit boards (160c, 162c in FIG. 7) parallel to the feed element layer. One of the two boards has 87 dividers (e.g. 51td, FIG. 5) that each divide a signal to be transmitted into seven portions, and the other board has 134 combiners (e.g. 38tc) that each collect seven transmit signal portions and deliver the sum to one of the feed elements. A similar arrangement is used to handle received signals, with 134 receive signal dividers (e.g. 38rd) on the one board, and 87 receive signal combiners (e.g. 51rc) on the other board.

Abstract: The present invention relates to a multibeam antenna arrangement having minimal aberration of astigmatism and coma over a wide area of the focal surface of the antenna. The present antenna comprises a plurality of N reflectors arranged confocally in a sequence along a feed axis of the antenna and at least one feed disposed in the vicinity of a focal point on the focal surface. The reflectors and the at least one feed are further arranged to provide an equivalent centered antenna arrangement with the longitudinal axis of the feed corresponding to an equivalent axis of the centered arrangement for eliminating astigmatism. Coma is then eliminated by deforming two of the N reflectors in a predetermined manner.

Abstract: A circularly polarized electromagnetic-wave radiator, formed from a rectangular section waveguide and a dipole, is energized directly by the guide and placed in the extension of its largest faces. An associated reflector element enables coincidence of the two respective phase centers of the guide and the dipole.

Abstract: An array antenna comprised of n individual elements where n is an integer wer of the base two. The individual elements have predetermined space code positions N which are varied by means of a plurality of tracking loops comprised of a portion of receiver apparatus coupled to the array and a null seeking detector which is adapted to vary the space code positions of the elements such that the elements are selectively spaced at respective N' locations relative to the N locations to provide a predetermined 180.degree. phase difference between sets of elements operating in pairs at each space angle of arrival of each of M interference signals whereby a null and substantially complete cancellation of the interfering sources are simultaneously provided while retaining the ability to receive the desired signal at its peak received value.

Abstract: A free standing antenna formed with an elongated tubular body portion, having one or more sections, and an enlarged base portion at its lower end for mounting thereof, and the body portion having a plurality of layers or reinforcing filaments, some of the layers being bundles of longitudinal filament rovings running lengthwise, and others of the layers being generally circumferential windings of filament rovings, the layers being bonded together by resin material; electrically conductive elements embedded in the tubular structure, and running from end to end, an annular electrically conductive collar connected to the conductive elements adjacent the lower end of the structure, a female threaded socket connected to the collar, and extending through a wall of the tubular structure for connection from the exterior, at least one layer of woven reinforcing filament cloth material extending up the interior of the tubular structure adjacent the lower end, and overlying the interior of the collar, and, resin bonding