Abstract: An improved helix antenna including a single unitary antenna having plural radiating elements extending radially from a common junction. A microstrip balun is connected to the plural antenna elements at the common junction. In a particular embodiment, the antenna includes four radiating elements arranged in a helical pattern and mounted such that a longitudinal axis extending through the axial center of the antenna is coincident with a longitudinal axis of the microstrip balun. One or more of the radiating elements includes a semi-circular loop to create phase relationships necessary for a circularly polarized beam pattern. The microstrip balun includes a transmission line and a ground plane on opposite sides of a dielectric substrate. The transmission line and the ground plane are tapered for impedance matching between the input and the output thereof.

Abstract: An ultra-broadband transverse electromagnetic (TEM) exponential antenna in which the radiating or receiving structure comprises first and second elongated conductors have a feed end comprising first and second narrow conductor strips. At an opposite radiating or receiving end, the widths of the first and second conductors expand exponentially in the H-plane, and the spacing between the first and second conductors expands exponentially in the E-plane, thereby providing a double flared, exponentially tapered, transverse electromagnetic horn antenna. Two TEM horn design embodiments are described herein and differ only in the lauching device by which the radiating structure is fed, which converts an input unbalanced transverse electromagnetic wave into a balanced transverse electromagnetic wave. A first preferred embodiment employs a stripline infinite balun as a launching device, while a second embodiment employs a cavity backed waveguide as a launching device.

Abstract: An antenna assembly includes a dipole antenna (D1, D2) and a monopole antenna (C1) having substantially perpendicular polarization directions. The dipole antenna (D1, D2) is provided with a balun (E1, E2) a portion (E1) of which serves as a backplane for a microstrip transmission line (G0, G1, G2) which transmits RF signals. The microstrip transmission line includes a first portion (G0) connected to a coaxial feed cable (F), a second portion (G1) having its ends respectively connected by a first switch (A) to the monopole antenna (C1) and a second switch (B) to the balun portion (E1) and a third portion (G2). When the switches (A, B) are closed to render the monopole antenna (C1) operative, the third portion (G2) serves to detune the dipole antenna (D1, D2). The assembly may be formed as a two-sided printed circuit board.

Abstract: A vehicle antenna for a cellular telephone has a balanced-unbalanced (BALUN) transformer that is connected to the telephone and is coupled to a horizontally polarized antenna on the interior of the vehicle and to a vertically polarized antenna that is located on the exterior of the vehicle. The vertically polarized component of a received signal is combined with the horizontally polarized component of the same signal in the transformer element and is applied to the cellular telephone. Signals to be transmitted are applied to the the transformer element and are divided into two portions, one of which is applied to the vertically polarized antenna and the other of which is applied to the horizontally polarized antenna. Because signals from a remote cellular transmitter cell arrive with both a vertical and a horizontal component, the antenna of the present invention retrieves the horizontal component which would otherwise be lost and combines it with the vertical component for more reliable signal reception.

Abstract: A metal flared notch radiator with separate and isolated transmit and receive ports for an active array. A 4-port circulator is integrated into the transition of the radiator so that the integrated device has have a separate transmit port, a separate receive port, and a separate termination port to provide isolation between the transmit and receive.

Abstract: The present invention relates to a microribbon/wave guide line transition, especially between an antenna (1) of the plate antenna type, with radiating elements (3) and feed lines (4) printed on a face of a substratum (2) and a wave guide or a resonant cavity (12) with a rectangular section. The end wall of the wave guide or of the cavity (12) is in a plane parallel to the plane that contains the radiating elements (3) of antenna (1) and their feed lines (4).

Abstract: The disclosure relates to a multipolarized broad band antenna and antenna system wherein the antenna structure is formed on a substrate, the antenna structure on the substrate including a central feedpoint, a first antenna element having a plurality of regions composed of first plural interconnected concentric sectors of circles of diminishing radius extending to the feedpoint, and a second antenna element having a plurality of regions composed of second plural interconnected concentric sectors of circles of diminishing radius extending to the feedpoint, the second plural concentric sectors being interleaved with the first plural concentric sectors.

Abstract: A low cost, high efficiency, end fed half wave folded dipole radio frequency antenna. The antenna includes an improved balun including a conductive tubular base secured to a conventional coaxial cable connector, a conductive tube telescoped relative to the base with a slot between the base and tube having an area corresponding to the extent the tube and base are telescoped together and two wires within the tube connected to the coaxial connector and each having an insulating sleeve. A folded wire loop antenna is connected to the wires and extends away from the balun. The loop may include coils to improve the gain of the antenna. A tubular insulating housing encapsulates the antenna.

Abstract: A hybrid circuit module having first and second pairs of input terminals and four output terminals. First, second, third and fourth baluns each include first and second transmission line wires. The baluns are configured between the input and output terminals to isolate sources when placed across pairs of input and output terminals. An antenna system is formed with the hybrid circuit module and a plurality of radiators. The circuit module may be configured to simultaneously generate or receive two or more independent radiation patterns. A method is provided for feeding a multiarm antenna structure with a hybrid circuit network. The method includes the steps of symmetrically positioning a conductive element with respect to all of the arms, and coupling terminals of the antenna arms to the network through a conductive element. Alternately the second terminals may be electromagnetically coupled to the network without requiring the conductive element.

Abstract: A broadband dual polarized antenna includes pairs of electrically separated stacked spiral antenna arms. Each pair of spiral arms have opposite senses and are orthogonal to each other. The relative overlap of each pair of spirals is kept to a minimum so that radiation received and transmitted by the bottom pair of spiral arms will be degraded as little as possible. No overlap exists within each pair of spiral arms, and the pair need not be co-planar, but do share a common axis with the other pair of spiral arms. The spiral arms can be segmented or may comprise a number of spiralling wire elements. A plurality of such antenna structures can be formed into an array capable of beam shaping or scanning.

Abstract: A balancing loop including a housing inside of which is disposed a first conductor part having a first sublength and a second sublength, with the first sublength constructed as a coaxial line passing through the housing and having its inner conductor terminated inside the housing and connected to a second conductor part, and the second sublength extending from the termination of the inner conductor to the second conductor part to an output line. The second conductor part also has the first and second sublengths and extends spaced apart from and parallel to the first conductor part. The second conductor part has one side connected to the housing and the other side to another output line. The output lines connected to the first and second conductor parts thereby form two symmetrical output lines which lead out of the housing. At least one variable capacitor is arranged between the first and second conductor parts to tune the balancing loop over the operating frequency range.

Abstract: A means for feeding or extracting radio frequency energy from an antenna element which uses coaxial transmission line, without upsetting the antenna elements physical or electrical symmetry, thus providing improved standing wave ratios and near theoretical radiation patterns. Because coaxial cable is inherently unbalanced, double reactance cancellation and resistance transformation are integrally provided by a feed loop shunted across the antenna element improving performance.

Abstract: An RF connector for connecting a radiotelephone (1) to an external antenna, whereby the telephone and a corresponding device rack (2) are connected to the external antenna by two pairs of matching metal plates (1a, 2a, 1b, 2b) that provide a capacitive two-wire connector-interface. In order to avoid too large a size and too high an attenuation, a coil (3a, 3b) is connected in series with the pair of plates (1a, 2a; 1b, 2b) constituting each capacitor. The coil and capacitor are dimensioned so that they form a resonant circuit with an attenuation of nearly 0 at the desired transmission frequency. A first balancing transformer (4) before the resonant circuit transforms the signal into a balanced signal, and a second balancing transformer (5) after the resonant circuit transforms the signal back to an unbalanced signal to be transmitted further on a coaxial cable.

Abstract: An exponentially tapered slot (Vivaldi) antenna for producing an end-fire beam. The antenna features a novel balun for coupling with a feed line. The conventional Vivaldi antenna is fed by means of a stripline section (1) underlying the ground plane (5) and lying perpendicular to the axis of the slot line (3). This balun arrangement has an inherent narrow bandwidth. In the proposed antenna arrangement the slot line (14) and the stripline (16) each have a 45.degree. twist centered on a common cross-over point (X.sub.o,Y.sub.o). The stripline (16) is terminated by a short-circuit to the ground plane (12) and the slot line (14) is terminated by an open-circuit in the form of a circular slot (15). The E-plane and H-plane radiation characteristics are similar to those of the conventional Vivaldi antenna, but the arrangement has a broadband capability enabling operation over any 3 to 1 bandwidth in the frequency range 1 to 40 GHz.

Abstract: A signal receiver with a cabinet and mono-pole antenna mounted outside of the cabinet with a signal receiving apparatus mounted inside of the cabinet. A shielded conductor is mounted inside of the cabinet as another antenna to be used with the mono-pole antenna. A balun which has first and second input terminals and an output terminal, and the first and second input terminals of the balun are connected to the mono-pole antenna and to the shield conductor and the output terminal is connected to the signal receiving apparatus.

Abstract: A low temperature plasma generator having reduced radio frequency (RF) emissions, and a method for reducing the RF emissions of a plasma generator. A low temperature plasma generator (100) includes a pair of electrodes (150 and 160) that are energized by an RF power supply (138) through a balanced impedance matching network (200). The impedance matching network includes a balun transformer (158), matched variable inductors (222 and 230), a fixed capacitor (240) in parallel with a variable capacitor (244) and a fixed capacitor (242) in parallel with a variable capacitor (246). The RF potential on electrodes (150 and 160) varies sinusoidally between opposite positive and negative values with respect to ground potential, such that the net potential on the two electrodes with respect to ground is always substantially equaol to zero, thus eliminating a glow discharge current and radiation emissions that otherwise are produced by similar prior art low temperature plasma generators.

Abstract: A low-profile patch radiator for use in an array antenna has a multilayer structure which includes a double-tuned impedance matching network and balun and a coaxial feed for linear polarization of the radiated waves. A second embodiment further includes a second double-tuned impedance matching network and balun and a second coaxial feed for dual polarization operation. The matching networks/baluns, which comprise microstrip circuits on Duroid substrates, increase the frequency bandwidth of the patch radiator.

Abstract: A microwave balun transformer provides an extension of operating frequency range particularly in conjunction with a cavity-backed spiral antenna (5). The balun cavity (13) has a dipole (15,17) extending between an unbalanced coax port (19) and an opposite end wall (29), the dipole junction (16) being connected to a balanced twin line (7). The length of the cavity is effectively controlled to make it closer to (two) quarter-wave stubs by inserting a frequency dependent reflector (21) at each end of the dipole. At low frequencies the reflectors are transparent thus giving the full length of the cavity, while at high frequencies the reflectors reflect and effectively shorten the cavity.

Abstract: This invention relates to a push-pull transformer for use in a high frequency push-pull amplifier. This push-pull transformer has a coaxial line whose one end is connected to an input terminal, while the other end thereof is provided with an internal conductor and an outer conductor, the internal and outer conductors being grounded through stubs. A capacitor having a proper capacity is connected between the internal conductor and the outer conductor whereby the push-pull transformer can be properly actuated in a low frequency range other than the frequency used without any necessity to enlarge the size of the stubs.

Abstract: A well logging apparatus is disclosed which employs slot antennas having a plurality of conductive probes traversing the slot. Also disclosed are a logging apparatus having electrically isolated antenna probes and a logging apparatus with an improved means for generating and applying a reference signal used in phase detection.

Abstract: An balun/antenna apparatus is provided which is capable of being fabricated on a printed circuit board substrate by automated equipment. The balun-antenna includes a microstrip groundplane conductor which is split into two balanced ground arms at one end. The split groundplane conductor operates as both a balun and as a radiating conductor. A unique microstrip excitation structure is situated above the split ground elements on the opposed surface of the substrate to excite the antenna with radio frequency energy.

Abstract: An improved element for use in an electrically steered antenna array is disclosed comprising a dipole, an integral balun and a 180.degree. phase shift bit. The arrangement utilizes printed circuit techniques throughout using an unbalanced microstrip for connection to electrical circuitry, a balun for transitioning from unbalanced microstrip to a balanced dipole antenna and includes a low loss 180.degree. phase shift bit formed by the use of a branched feed network including two diodes whose conductive states determine the sense of antenna excitation, and produce the equivalent of a 180.degree. phase shift bit.

Abstract: The present invention is a moisture-insensitive system adapted to couple radio frequency energy at a low impedance from a matched two conductor transmission line, through a vehicle windshield and to an antenna in a manner which minimizes stray radio frequency radiation within the passenger compartment of the vehicle. The system includes two pair of conducting plates, one pair mounted on each side of the windshield, each pair opposite the other pair. A coaxial feed line is coupled to the inside pair of plates and a matching circuit is connected across the outside pair of plates. A full-size, unloaded antenna element is connected to the output of the matching circuit. A decoupling device, such as a decoupling sleeve or a RF choke, can be used to minimize RF current flow on the shield conductor of the coaxial feed line. The coaxial cable is coupled directly through the windshield, without an intervening matching network, so that RF energy at a low impedance is coupled to the outside pair of plates.

Abstract: An balun-antenna arrangement is provided which is capable of being fabricated on a printed circuit board by automated equipment. The balun-antenna includes a microstrip transmission line which is coupled to one end of a split microstrip transmission line having opposed ends. An antenna which is symmetric about its feedpoint is coupled to the remaining end of the split microstrip transmission line.

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: An antenna for CP signals uses a reflector, such as a truncated pyramid. Feed tubes, which act as a balun extend from the pyramid. Four truncated square loops are coupled to the feed means. The truncation results in a smaller radome being used and hence smaller wind resistance. A feed strap has a capacitance hat for a better match.