Abstract: A monopole antenna is mounted on a ground plane and incorporates a radiating structure such as a disc or hollow cap parallel to the ground plane, for loading the antenna. An elevated feed is formed by a biconical central post between the radiating structure and the ground plane. Tuning is also accomplished by a partial or total circumferential dielectric (which may also function as a support) having an outer electrically conducting sheet spaced apart from the central post to provide shunt capacitance, and by outboard inductive posts which connect between the ground plane and the radiating structure to provide shunt inductance. Alternatively, additional tuning may be accomplished by a circuit between the upper and lower portions of the central post.

Abstract: An antenna system for radiating information in the ELF range is disclosed and comprises an extended conductor sized to produce a corona at the operating voltage. In the preferred embodiment, "ultra-thin" wire is used as the antenna element for weight savings and is lofted by means of a tether line which absorbs the stresses. Means are provided for helically winding the antenna element around the tether line.

Abstract: A horn antenna comprises a horn of the type including a rectangular throat, a rectangular opening located in a plane parallel to and spaced part from the throat and having at least one dimension larger than a corresponding dimension of the throat, and four wall portions joining the throat and the opening. An electrically conductive member is disposed so as to define any one diagonal across the horn from and including the opening to and including the throat.

Abstract: Two or mutually nonparallel dipoles for operation over a common frequency band. Each of the dipoles has a central feed port and an inner end connected to a junction box with conductive walls. Each feed port is connected through a junction in the box to a receiver for the common frequency band. For diversity, two receivers for the common frequency band are connected to the two feed ports. For pseudodiversity, the dipoles are connected to a common receiver and are positioned to have noncoincident phase centers separated by more than one-quarter wavelength over some part of the common frequency band.

Abstract: To simplify the construction of a telescopic antenna which is projected and retracted, respectively, by a flexible wire, a rotatable wind-up drum (10) is formed with an inner space (17) to provide for wind-up of the flexible wire, the inner space, likewise, retaining a gear ring (20) in which gear projections (41) of the wire are engaged. The wire, preferably, is an elastic plastic wire element, coupled to the projecting telescoping element (A2) of a telescoping antenna (A), the drum (10) being driven by a motor (35) which receives rotation coupled thereto by a worm drive (29-34).

Abstract: A microstrip antenna is presented in which the circuit pattern is on the inner side of a glass plate and is spaced from the ground plane by an air dielectric. The outer side of the glass plate serves as a protective cover for the circuit pattern and the ground plane.

Abstract: The present invention relates to an antenna arrangement for correcting for astigmatism is a beam which is linearly scannable in a first principal plane of the antenna arrangement. The antenna arrangement comprises a parabolic or torus main reflector and a feed arrangement for producing first and second astigmatic phase centers which lie along first and second focal lines, respectively, in the first principal plane and match first and second astigmatic phase centers required by the main reflector to produce a linearly scannable plane wave.

Abstract: Suppression of selected sidelobes in a reflector antenna is accomplished by the positioning of two or more metallic disks on the reflector surface at specific distances above the reflector surface.

Abstract: An S-band antenna with a body having an inner circular tube and a coaxial outer circular tube in which the circumference of the outer tube is one wave length of S-band radar. A plurality of pairs of axially elongated slots are provided in the outer tube in which the slots of each pair are diametrically opposed to each other. Adjacent pairs of slots are axially displaced from each other a distance of one-half wave length. The pairs of slots are rotationally offset at an angle equal to 360/N where N is the number of pairs. A dielectric cover is provided around the outer tube.

Abstract: An antenna of the type having a central driven element and a plurality of surrounding parasitic elements is shown. Further, there is circuitry for modifying the basic omnidirectional pattern of said antenna to a directional pattern by normally capacitively coupling the parasitic elements to ground but on a selective basis changing some of the parasitic elements to be inductively coupled to ground whereby they act as reflectors and provide an eccentric signal radiation pattern. By cyclically altering the connection of various parasitic elements in their coupling to ground, a rotating directional signal is produced.

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 has 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 monopulse spiral antenna system of the type having a minimum of three, interwound spiral arms for multimode, direction of arrival sensing, is disclosed in which the antenna arms are shaped and arranged in an overlapping configuration that allows the interarm impedance of the antenna to be adjusted, substantially independently of other electrical properties of the antenna, for matching of the antenna impedance of a mode forming network while preserving the broadband, directional capabilities of the antenna. Several different embodiments of the impedance adaptive antenna are disclosed including a preferred, eight-arm exponential spiral in which the arms are conductive strips transversely inclined relative to a plane formed by the spiral so that opposed and parallel surfaces of adjacent arm strips create a dominant interarm capacitance that in turn determines the overall input impedance of the antenna.

Abstract: An eight-band vertical antenna which is omnidirectional and includes completely automatic band switching for the amateur radio frequencies of eighty/seventy-five meters, forty meters, thirty meters, twenty meters, seventeen meters, fifteen meters, twelve and ten meters. The vertical antenna has a low angle of radiation and a low standing wave ratio on all frequencies which provides for direct coaxial cable transmission line feed. The eighty-meter and forty-meter inductor-capacitors are in parallel while the thirty-meter inductor-capacitor is in series with a portion of the forty-meter circuit providing inductive reactance for operation on eighty/seventy-five meters, forty meters, and thirty meters with a series inductor-capacitor connected between an upper vertical radiating element and the forty-meter inductor while permitting simultaneous resonance on each of the three higher frequencies of twenty, fifteen and ten meters.

Abstract: In general a coaxial feeder connected directly into the center of a half-wave dipole antenna disturbs electrical balance and therefore reduces the effectiveness of the screen of the feeder. In the present invention a dipole with two quarter-wavelength elements symmetrically connected through respective identical capacitors to the screen of the feeder is fed through an inductor connected to the junction between one element and its capacitor. By having equal reactances, the capacitors balance the dipole to earth and by means of its phase delay the inductor restores a resistive impedance termination for the feeder.

Abstract: A low profile antenna comprised of a driven element and a parasitic element spaced above a ground plane. The driven element is connected at one end to the feedpoint of the radio device to which it is attached, the opposite end thereof being free. The parasitic element is connected to the ground plane by its end nearest the feedpoint, the opposite end thereof being free. In the preferred embodiment the parasitic element length and the driven element length are both approximately equal to a quarter wavelength at the operating frequency.

Abstract: A stove pipe elbow connection formed by using two pipes cut at 45 degrees angles and connected by flanges rotatable on each other provides elevation adjustment for a dish antenna between zero degrees and 90 degrees, with the base pipe projecting upwardly perpendicular to the earth surface. The base pipe is rotated about its axis until the flange connected projecting pipe points north and that assembly fixed. A two tube assembly having an inner tube slid over the angled projecting pipe and an outer tube fixed to the inner tube but having its axis at an angle of approximately 12 degrees thereto for correcting for maximum declination supports the antenna which rotates about the axis of the inclined outer pipe to adjust for declination. The antenna is bolted in place after the proper declination angle is reached and further rotation of the antenna about the axis of the pipe projecting causes the antenna to sweep across all of the satellites in the geosynchronous orbit sector bearing such satellites.

Abstract: A coil assembly that is essentially isotropic in a plane normal to the plane of the coil includes two flat coils stacked one next to the other. One coil is connected in series with a resistor in a closed loop and has a strip of high permeability material woven through it. The other coil is tuned by a parallel capacitor across its coil terminals, such terminals being connected to electronic circuitry. The coil is separated from the printed circuit board that contains the electronic circuitry by a sheet of high permeability material. The assembly is self-contained and powered by a flat battery on which the circuit board is placed. Another embodiment is disclosed that contains only one coil, the terminals of which are connected to a suitable electronic circuit, not shown. Strips of high permeability material are disposed on both sides of the coil and an assembly is produced with a printed circuit board and a flat battery.

Abstract: A radiating or receiving element for orthogonally polarized high-frequency signals comprises, on both sides of a first layer having a first cavity, first and second perpendicular high-frequency transmission lines and at the other side of the transmission lines a second layer having a second cavity and a third layer having a third cavity facing the other two cavities but short-circuited so as to form a reflecting plane, the transmission lines being constituted by symmetrical slots and conducting strips, which are provided in the median plane of these lines and whose ends project into the cavities to form exciting probes whose lengths are different and chosen such that for any predetermined thickness of the first layer, the pairs of values: lengths of the end of a probe/distance of the probe to the sole reflecting plane correspond to an experimentally maximum or nearly maximum coupling between each of the probes and the propagation medium.

Abstract: An elongated active element for an antenna has an internal resonator providing a high quality matching impedance. The internal resonator is formed by a pair of conductors including an outer conductor and a coaxial inner conductor that is connected to signal ground. The signal connection of the active element is made to one end of the outer conductor in the neighborhood of the ground connection to the inner conductor. The inner conductor is shorted to the outer conductor at approximately a quarter of a wavelength, plus an integral number of half wavelengths, from the signal and ground connections to provide a parallel-resonant condition complementing the series resonant characteristics of the radiation impedance of the active element. Preferably, the active element is approximately a quarter wavelength long, and may be lengthened or shortened to obtain a desired radiation resistance. The antenna is easily fabricated from a length of coaxial cable.

Abstract: A motorized antenna mount for rotationally and pivotally supporting a satellite dish on a main vertical support pole. A base is adjustably mounted on the top of the support pole by a plurality of plumb bolts to compensate for any vertical misalignment of the pole. A motor housing is pivotally mounted on the base by a hinge and pair of curved pivot guide tracks. An electric motor is mounted in the motor housing and is connected to a drive gear through a gear reducer for rotating a turret which is mounted by a thrust bearing on turret mount attached to the top of the motor housing. The satellite dish is mounted on the end of a support arm which is pivotally adjustably mounted on the turret for declination angle control thereof. The turret has an internal arcuate-shaped gear track extending preferably 180.degree. about a central opening formed in the interior of the turret and engageable with the motor for rotating the turret drive gear.