Abstract: What is disclosed is a surface wave antenna configured to install on an electrically conductive structure. The surface wave antenna includes a first portion comprising a conductive element and an attachment element, and a second portion comprising a conductive element and an attachment element. The conductive element of the first portion and the conductive element of the second portion are configured to each form a conductive longitudinal portion of a horn receive element, and the attachment elements are configured to conductively couple the conductive elements together to form the horn receive element. The surface wave antenna also includes a dipole element comprising a first transmit element and a second transmit element. The surface wave antenna also includes a mounting element comprising a first dielectric mount and a second dielectric mount.

Abstract: A new class of feed horns is provided based on the use of metamaterial printed circuit board (PCB) liners on the walls of the feed horns. These feed horns may be implemented to achieve low cost operation. PCBs making up the metamaterial liner may be assembled together in such a manner as to form a feed horn with a square or rectangular aperture shape, although other suitable shapes are possible. These PCBs may be fabricated from standard low cost, off-the-shelf dielectric material. A conductor artwork pattern on the PCB surface forming the interior surface of the feed horn can be designed such that the PCB feed horn yields radio frequency (RF) properties similar to that of a corrugated feed horn. A simple flat plate ground plane bonded to the back side of the PCB can serve as the feed horn structure.

Abstract: A frequency down converter. A plate body of the frequency down converter includes a main surface. A first wave guide includes a first section and a second section connected to the first section. The first section is connected to the main surface and extends parallel thereto. The second section extends perpendicular to the main surface. A second wave guide includes a third section and a fourth section connected to the third section. The third section is connected to the main surface and extends parallel thereto. The fourth section extends perpendicular to the main surface.

Abstract: A device for at least one of receiving and transmitting electromagnetic radiation includes a feedhorn having a substantially smooth, electrically conducting inner surface extending from an open end to a feed end, the inner surface being substantially rotationally symmetrical about a longitudinal axis, wherein an orthogonal distance from a point on the longitudinal axis to the substantially smooth, electrically conducting inner surface increases monotonically as the point on the longitudinal axis is selected at successively greater distances from the feed end of the feedhorn towards the open end of the feedhorn such that a profile of the substantially smooth, electrically conducting inner surface of the feedhorn is monotonically increasing. The feedhorn has an operating bandwidth and the feedhorn provides a maximum of ?30 dB cross polarization response over at least 15% of the operating bandwidth.

Abstract: A wireless communication antenna device includes a horn antenna and a waveguide. The horn antenna for transmitting or receiving a polarized wireless electromagnetic wave having a first electric field component and a second electric field component, the first electric field component and the second electric field component being orthogonal with each other. The waveguide connected to the horn antenna, for propagating the polarized wireless electromagnetic wave. Wherein a first opening of the waveguide includes a side corresponding to the first electric field component and another side corresponding to the second electric field component, and a length of the side corresponding to the first electric field component is different from a length of the side corresponding to the second electric field component, such that the first electric field component and the second electric field component have a phase difference therebetween when the polarized wireless electromagnetic wave is propagated in the waveguide.

Abstract: Electrically large, stepped-wall or smooth-wall, direct-radiating horn antenna apparatus that may preferably be used in satellite spot beam applications. Exemplary electrically large smooth-wall horn antenna apparatus comprises one or more input ports, an electrically large output port, and a smooth-wall or stepped-wall tapered section having a spline-shaped profile extending from the input port(s) to the output port of the apparatus. The spline-shaped profile is preferably monotonic and is preferably configured to generate a spot beam. The spline-shaped profile may be configured to support multiple frequency bands, and dual simultaneous polarization having either linear or circular polarization. The spline-shaped profile is defined by spline knots, and, the knot radii form a nondecreasing sequence. Preferably, the spline-shaped profile comprises a piecewise cubic Hermite interpolating polynomial spline that interpolates the shape of curves between the spline knots.

Abstract: A device comprising a metallic conical portion, said conical portion substantially hollow having a vertex end and a base end, a first cylindrical portion disposed annularly about the base end of the conical portion, a metallic second cylindrical portion coupled to the vertex of the conical portion, said cylindrical portion having a threaded aperture, and an antenna feed coupled to the threaded aperture. The device may have a patch disposed on an insulator portion connected to the second cylindrical portion, said patch and insulator portion each having an aperture, and a metallic ground portion connected to the insulator portion, said ground portion having an ground aperture, and a threaded screw disposed through the ground aperture, the patch, the insulator aperture and into the threaded aperture. An RF feed may be created by coupling the threaded aperture to a conductive material disposed on the insulator portion.

Abstract: A device comprising a metallic conical portion, said conical portion substantially hollow having a vertex end and a base end, a first cylindrical portion disposed annularly about the base end of the conical portion, a metallic second cylindrical portion coupled to the vertex of the conical portion, said cylindrical portion having a threaded aperture, and an antenna feed coupled to the threaded aperture. The device may have a patch disposed on an insulator portion connected to the second cylindrical portion, said patch and insulator portion each having an aperture, and a metallic ground portion connected to the insulator portion, said ground portion having an ground aperture, and a threaded screw disposed through the ground aperture, the patch, the insulator aperture and into the threaded aperture. An RF feed may be created by coupling the threaded aperture to a conductive material disposed on the insulator portion.

Abstract: A composite polarizer including a first polarizer having a plurality of parallel metal vanes and a second polarizer having a plurality of parallel layers of dielectric material is provided. The first polarizer is disposed on an axis, and has a phase advance orientation orthogonal to the axis. The second polarizer is disposed on the axis and has a phase advance orientation orthogonal to the axis. The first polarizer has a first differential phase shift for a first frequency f1 and a second differential phase shift for a second frequency f2. The second polarizer has a first differential phase shift for the first frequency f1 and a second differential phase shift for the second frequency f2. A total of the first differential phase shifts of the first and second polarizers is about 90°, and a total of the second differential phase shifts of the first and second polarizers is about 90°.

Abstract: A horn antenna includes smooth-walls with multiple slope discontinuities. The horn antenna may have more than an octave bandwidth with a 2.25:1 bandwidth ratio to cover the frequencies of 20 GHz, 30 GHz, and 45 GHz, or all the desired bands for military or other communications.

Abstract: A horn antenna includes smooth-walls with multiple slope discontinuities. The horn antenna may have more than an octave bandwidth with a 2.25:1 bandwidth ratio to cover the frequencies of 20 GHz, 30 GHz, and 45 GHz, or all the desired bands for military or other communications.

Abstract: An antenna uses a photonic forbidden band (PFB) material in which, by default, a surface (26) for injecting and/or receiving electromagnetic waves in a resonance cavity of the antenna (8) has at least a width or a length of a diameter higher than or equal to the wavelength of the working frequency.

Abstract: A beamwidth adjustment device, which is used for a feedhorn comprising an opening and a ring encircling the opening, comprises a conductor used for adjusting beamwidth formed by the feedhorn according to a characteristic of a dish of a satellite antenna corresponding to the feedhorn, and a fixing element used for fixing the conductor to the feedhorn, wherein the satellite antenna is used for receiving signals from the feedhorn.

Abstract: An array of feedhorns feeds detected radiation through waveguides to diode-based mixers to produce modulated intermediate frequency (“IF”) signals. The mixers and waveguides are accommodated on a substrate surface and multiple substrates can be layered up to support a two-dimensional array of waveguide openings in a face of a waveguide/mixer block. A feedhorn block is brought into register with this face so that each waveguide opening connects with a feedhorn. An end portion of each feedhorn is drilled into the opening of a respective waveguide. The main feedhorn block and the waveguide/mixer block are then assembled into registration. This method of construction avoids transverse interfaces in the walls of the feedhorns or waveguides just at the point where the transition is made from one to another.

Abstract: Provided is a planar antenna based system for use as a radar level meter, microwave barrier or other suitable system. The system includes a planar radiator element arranged on a substrate, and a cover plate element made from a dielectric to cover the planar radiator element. In one alternative embodiment, the cover plate includes a cavity proximate the planar radiator element, into which the microwaves generated by the planar radiator element can be coupled. In another alternative, the cover plate is provided in a surface-flush position against the substrate in the edge region of the cavity. These arrangements may be provided in a plurality so as to support an overall system containing multiple radiator elements.

Abstract: A dual-band antenna is provided that combines two normally disparate communications modes into a single compact aperture minimizing overall mass and volume, while maintaining high performance efficiency and reciprocity of each individual mode. The antenna is compatible with both optical (near-IR/visible) and RF (microwave/millimeter-wave) transceiver subsystems for high bandwidth communications, applicable primarily to long- to extremely long-range (space-to-ground) link distances. The optical link provides high bandwidth while the RF provides a lower data-rate weather backup, accommodation for traditional navigation techniques, and assistance in cueing the extremely tight optical beam by matching the RF beamwidth to an optical fine-steering mechanism field-of-regard. The configuration is built around a near-diffraction-limited high performance primary mirror shared by both a direct-fed RF antenna design and a Cassegrain optical telescope.

Abstract: Forming an inlay comprising an antenna wire having two end portions and a site for a transponder chip, comprises: mounting the wire to a surface of substrate; and leaving the end portions of the antenna wire free-standing, as loops adjacent terminal areas of a site on the substrate for the transponder chip. With the transponder chip installed on the substrate, the free-standing loops are repositioned to be substantially directly over the terminals of the transponder chip, in preparation for interconnection of the loops to the terminals of the transponder chip, then are bonded to the terminals. An embedding tool for mounting the wire on the substrate may embed the wire in or adhesively place a self-bonding wire on a surface of the substrate. The substrate may have two transponder chips, and function as a secure inlay. An anti-skimming feature is included in the inlay.

Abstract: A low noise block converter feedhorn (LNBF) is disclosed. The LNBF comprises a PCB, a dielectric resonator oscillator (DRO), a chamber, a tuning screw, and a cover. The DRO is placed on the PCB. The chamber has a first partition, and the first partition is used to cover up the DRO. The chamber further comprises a round hole. The tuning screw passes through the round hole and is then used to adjust the oscillating frequency of the DRO. The cover is used to cover up the tuning screw in order to restrain the DRO from power leakage through the gap in between the round hole and the tuning screw.

Abstract: A cup waveguide antenna with integrated polarizer and OMT for simultaneously communicating left and right hand circularly polarized electromagnetic waves is adjustable to obtain efficient propagation and reception of electromagnetic waves. The antenna includes a circular waveguide having an orthomode transducer utilizing first and second pins longitudinally spaced apart and oriented orthogonally with respect to each other. Six radially-oriented adjustable polarizer screws extend from the exterior to the interior of the waveguide. A septum intermediate the first and second pins is aligned with the first pin. Adjustment of the polarizer screws enables maximized propagation of and/or response to left hand circularly polarized electromagnetic waves by the first pin while simultaneously enabling maximized propagation of and/or response to right hand circularly polarized electromagnetic waves by the second pin.

Abstract: A system and method for communication that could be used in an identification friend or foe system. The method comprises generating a first message by a processor and controlling a beam steerer to deflect transmitted waves toward a first angle. The method further comprises transmitting the first message through an antenna in communication with the beam steerer toward the spatial angle. The method further comprises controlling the beam steerer to deflect waves received from the spatial angle. The method further comprises receiving a responsive wave at the antenna through the beam steerer at the spatial angle, the responsive wave including a second message responsive to the first message.

Abstract: A horn antenna includes a conducting horn having an inner wall and a first dielectric layer lining the inner wall of the conducting horn. The first dielectric layer includes a metamaterial having a relative dielectric constant of greater than 0 and less than 1. The horn antenna may further include a dielectric core abutting at least a portion of the first dielectric layer. In one aspect, the dielectric core includes a fluid. A waveguide including a metamaterial is also disclosed.

Abstract: A radiator element for RF transmission and reception over a wide band of frequencies. The radiator element is formed of conductive material on substrate surface of conductive material in the form of a pair of horns extending in opposite directions to distal tips defining the widest distance of a mouth of a cavity. The mouth reduces in cross-section to a narrowest point in between said pair of horns. The resulting radiator element will radiate and receive frequencies between frequencies the distance of the widest point and narrowest point are sized to receive.

Abstract: A dual circularly polarized antenna is described. In some embodiments, the antenna includes a waveguide having an aperture at a first end and a conducting component at a second end, the conducting component shorting the waveguide. A first driven dipole is substantially orthogonal to a second driven dipole, and both the first and second driven dipoles are located near the aperture of the waveguide. The first and second driven dipoles are connected to the conducting component by one or more plates and configured to be fed in quadrature. A resonator is positioned near the first and second driven dipoles.

Abstract: A multiband satellite antenna is provided. The multiband satellite antenna includes a plurality of first band wave receivers and a second band wave receiver. The first band wave receiver includes a first band wave guide, and the second band wave receiver has a first receiving unit and a second receiving unit. The first receiving unit and the second receiving unit are disposed on opposite sides of an alignment line of the first band wave receivers. Each of the first receiving unit and the second receiving unit has a second band wave guide. Output ends of the first receiving unit and the second receiving unit are coupled together to combine signals received from both units into a single signal, and then the single signal is outputted as a second frequency signal. Through this design, in a high satellite density environment, dual-frequency signals from several satellites at similar elevation angles can be received by the antenna of the invention.

Abstract: A multi-feed horn includes a first feed horn, a second feed horn and a third feed horn which are connected to a first waveguide, a second waveguide and a third waveguide, respectively. The first feed horn is provided with a first proximal end opening and a first tip opening which are rectangular in shape, the second feed horn is provided with a second proximal end opening and a second tip opening which are rectangular in shape, and the third feed horn is provided with a third proximal end opening and a third tip opening which are rectangular in shape. Consequently, a multi-feed horn, a low noise block downconverter and an antenna apparatus which allow a further improvement in the reception characteristic and in the manufacturing accuracy can be provided.

Abstract: A wide band antenna tracking modulator and method is disclosed. The system includes a common port for receiving an electromagnetic signal, a waveguide connected to the common port, at least a pair of side arms and a pair of coupling slots separated along an axis of the waveguide coupling the electromagnetic signals between the waveguide and the pair of side arms. The pair of coupling slots substantially coupled a higher order TE mode signal while substantially not coupling a primary TE mode signal. The method includes substantially coupling a higher order Transverse Electric (TE) mode signal of the electromagnetic signal while substantially not coupling a primary TE mode signal of the electromagnetic signal to at least a pair of side arms coupled to the wave guide though a pair of coupling slots separated along the axis of the waveguide.

Abstract: An antenna element-waveguide converter includes an antenna substrate having, on one surface, an antenna element and rectangular metal plates arranged in a plurality of rows to surround this antenna element, and a waveguide having, at one end, an opening opposed to the one surface of the antenna substrate. Surfaces of the rectangular metal plates and the opening of the waveguide are arranged with a predetermined gap left therebetween in a direction perpendicular to the one surface of the antenna substrate. Thus arranging the antenna substrate and the waveguide avoids a stress due to assembly variations, which can achieve favorable antenna characteristics.

Abstract: A dual- or quad-ridged horn antenna with an embedded impedance matching network is provided herein. According to one embodiment, the horn antenna may include at least one pair of ridges arranged opposite one another for guiding an electromagnetic wave there between. A transmission line is coupled to a first one of the ridges for supplying power to, or receiving a signal from, a feed region of the horn antenna. To reduce impedance mismatches between the transmission line and the ridges, an impedance matching network is embedded within a second one of the ridges at the feed point. The impedance matching network reduces impedance mismatch and extends the operational frequency range of the horn antenna by providing a sufficient amount of series capacitance between the transmission line and the ridges at the feed region. As set forth herein, the impedance matching network is preferably implemented as an open-circuit transmission line stub or capacitive stub.

Abstract: A Ka/Ku-band transmitter-receiver comprises a tri-band feed of a Ka-band transceiver, in conjunction with an array of phase combined patch receiving, antennas that operate at the Ku-band frequencies.

Abstract: A feed horn and systems and methods of making and using the feed horn are presented. Exemplary feed horns include a first portion comprising a dual mode geometry and a second portion comprising an axial corrugation geometry. The feed horn may operate simultaneously in a plurality of separate frequency bands (e.g., from about 18.3 GHz to about 20.2 GHz and from about 29.1 GHz to about 30.0 GHz) and a plurality of separate waveguide modes (e.g., TE11, TM11 or HE11 modes); simultaneously operating over two bandwidth segments of at least 1900 MHz that are separated by at least 5000 MHz. The feed horn may have a short axial length (e.g. less than 4 wavelengths at 18.3 GHz), and it may be configured to operate in a prime fed offset reflector antenna system. In addition, the feed horn may be formed as a single piece via a single casting pull.

Abstract: Methods and apparatus for a feed assembly for a reflector antenna including an aperture common to low, mid, and high frequency bands, a polyrod design to launch signals in the mid and high frequency bands, a horn to launch signals in the low frequency band, a co-located phase center for launching signals in the low, mid, and high frequency bands, and a low-band monopulse array located on a surface about the aperture to track a satellite.

Abstract: A method and apparatus are provided for making radio frequency (RF) inlays. The RF inlays include an integrated circuit and an antenna affixed to a substrate material carrying the integrated circuit. During processing, portions of the wire forming the antenna are located adjacent to, but not directly over the integrated circuit. In the subsequent processing step, the wire ends are placed in contact with and secured to the integrated circuit terminal areas.

Abstract: The invention relates to an antenna (1) for a transmitting operation and/or a receiving operation with a decoupling apparatus (2a) and/or a coupling apparatus (2b) for electromagnetic waves. The antenna (1) according to the invention comprises a horn funnel (4) which is composed of at least two side walls (3a, 3b, 3c, 3d), and also comprises at least two fins (5a, 5b) which extend into the interior of said horn funnel (4). The at least two side walls (3a, 3b, 3c, 3d) have a cutout (7a, 7b) in each case.

Abstract: A device for determining distance between a rotor blade and a wall of a gas turbine surrounding the rotor blade is provided. A waveguide guides and emits electromagnetic waves of at least one frequency in the direction of the rotor blade through a waveguide opening facing the rotor blade. The electromagnetic waves are injected into the waveguide and reflected portions of the electromagnetic waves are received. An evaluation unit compares the phase of the electromagnetic waves to be injected with the phase of the reflected portions of the electromagnetic waves and determines phase comparison values for every frequency and the distance is determined based on the phase comparison values. The waveguide comprises a sealing element which is configured to be transmissible for the electromagnetic waves of the frequency and which has two opposite surfaces in the direction of guidance of the electromagnetic waves.

Abstract: Embodiments include systems and methods for over-the-air testing of wireless systems. Embodiments comprise separated anechoic chambers containing wireless devices. The anechoic chambers are connected by propagation path corridors.

Abstract: Embodiments of the present invention recite an improved signal receiver circuit and a method of implementation. In one embodiment, a first signal pathway of a low-noise block feedhorn comprises a ceramic low-pass filter coupled with a first polarity signal input. In accordance with embodiments of the present invention, a second signal pathway of the low-noise block feedhorn comprises ceramic high-pass filter coupled with a second polarity signal input.

Abstract: A multi-band transducer is described incorporating a coaxial waveguide interface for use with a multi-band feed and incorporating bent shaped probes yielding all-planar interfaces in microstrip for all frequency ranges and suitable for mass production. Hybrids can be incorporated for linear or circular polarization applications.

Abstract: A radio wave receiving converter includes a main body portion including a first waveguide having a male thread on an outer circumference of the first waveguide, a feedhorn including a second waveguide having a female thread on an inner circumference of the second waveguide, a ring-shaped member including a circumferential wall portion and an annular step portion such that a groove portion where a portion near a tip of the second waveguide is inserted between the ring-shaped member and the outer circumference of the first waveguide is formed, and a sealing agent injected into a groove portion “b”. By this configuration, there is provided a radio wave receiving converter that has a simple structure of a connecting portion, has improved productivity of the components and assemblability of the finished components, and can achieve a reduction in size and weight.

Abstract: A system and method for communication that could be used in an interrogate friend or foe system. The method comprises generating a first message by a processor and controlling a beam steerer to transmit waves polarized in a first polarization-direction toward a first spatial angle. The method further comprises transmitting the first message through an antenna in communication with the beam steerer toward the first spatial angle. The method further comprises receiving the first message at a target through a second antenna and generating a second message responsive to the first message by a second processor in communication with the second antenna. The method further comprises transmitting the second message in a responsive wave through the second antenna, the responsive wave polarized in a second polarization-direction distinct from the first polarization-direction; and receiving the responsive wave at the first antenna through the beam steerer.

Abstract: A system and method for communication that could be used in an identification friend or foe system. The method comprises generating a first message by a processor and controlling a beam steerer to deflect transmitted waves toward a first angle. The method further comprises transmitting the first message through an antenna in communication with the beam steerer toward the spatial angle. The method further comprises controlling the beam steerer to deflect waves received from the spatial angle. The method further comprises receiving a responsive wave at the antenna through the beam steerer at the spatial angle, the responsive wave including a second message responsive to the first message.

Abstract: A modular system is for assembling a fill-level radar antenna, a fill-level radar antenna, and o a fill level radar. The modular system comprises several modules that can be interconnected. In this way a host of different fill-level radar antennae may be produced that are optimally adapted to the corresponding conditions.

Abstract: A modular system is for assembling a fill-level radar antenna, a fill-level radar antenna, and o a fill level radar. The modular system comprises several modules that can be interconnected. In this way a host of different fill-level radar antennae may be produced that are optimally adapted to the corresponding conditions.

Abstract: The invention concerns a method for making a waveguide microwave antenna with corrugated horn, which consists in forming the corrugations of the horn on the outer surface of a synthetic material form block followed by surface metallization of the foam block configured to produce the antenna.

Abstract: A method for fabricating a microwave horn antenna in which a thermoplastic sacrificial layer is mounted to a thermoplastic horn layer. A heated horn embossing plate having at least one horn shaped embossing element is then moved into the horn layer so that the horn element penetrates through the horn layer and extends partially into the sacrificial layer thus forming a horn opening in the horn layer complementary in shape to the horn element. The horn layer and sacrificial layer are then separated from each other and the horn opening and at least a portion of the back surface of the horn layer is covered with a metal coating. A thermoplastic wave guide layer formed by embossing wave guide channels into the layer is covered with metal and attached to the back side of the horn layer to form the antenna. Alternatively, a portion of the horn and the remaining portion of a microwave channel are formed in both a first and second thermoplastic section.

Abstract: A conical radiator coupled to an antenna patch disposed along a first end of the radiator, said patch disposed on an insulator. A ground plane is connected to the insulator and a radome is disposed opposite a second end of the radiator. The radome has a first region presenting a convex surface towards the radiator, and the radome has a second region presenting a concave surface towards the radiator. The first end of the conical radiator is the apex of the cone. A ground plane is included and a portion of the ground plane is a planar surface and another portion extends away from the planar portion towards the radome. Also disclosed is a method for forming a radiation pattern by shaping the radome to effectuate a predetermined radiation pattern using localized convex and concave surfaces positioned on the radome at different points in relation to the conical radiator.

Abstract: A device comprising a metallic conical portion, said conical portion substantially hollow having a vertex end and a base end, a first cylindrical portion disposed annularly about the base end of the conical portion, a metallic second cylindrical portion coupled to the vertex of the conical portion, said cylindrical portion having a threaded aperture, and an antenna feed coupled to the threaded aperture. The device may have a patch disposed on an insulator portion connected to the second cylindrical portion, said patch and insulator portion each having an aperture, and a metallic ground portion connected to the insulator portion, said ground portion having an ground aperture, and a threaded screw disposed through the ground aperture, the patch, the insulator aperture and into the threaded aperture. An RF feed may be created by coupling the threaded aperture to a conductive material disposed on the insulator portion.

Abstract: A ground station antenna includes a LNB with at least one dipole, a feed horn, a waveguide between the LNB and the feed horn, and a rotation mechanism. By rotating a portion of the waveguide, the polarization of an electromagnetic wave propagating between the LNB and a satellite is transformed to match the polarization to (one of) the dipole(s) and to an antenna on the satellite. Another ground station antenna includes a main waveguide, two mutually orthogonal branch waveguides, a coupling mechanism for coupling two orthogonal antenna dipoles to the proximal end of the waveguide, and a transformation mechanism that transforms the polarization of an electromagnetic wave propagating between the branch waveguides and a satellite via the antenna dipoles to match the polarization to one of the branch waveguides and to an antenna on the satellite.

Abstract: A dual polarization multi-band antenna may include a waveguide horn, a low band feed section, a transition section, and a high band feed section coupled in series. The waveguide horn may be configured to support propagation of electromagnetic waves in a low band and a high band. The low band feed section may include horizontal and vertical feeds and may be configured to support propagation of electromagnetic waves in the low band and the high band. The high band feed section may include horizontal and vertical feeds and may be configured to support propagation of electromagnetic waves in the high band but not in the low band. The transition section may be configured to couple electromagnetic waves in the high band from the high band feed section to the low band feed section and to constructively reflect electromagnetic waves in the low band.

Abstract: A primary radiator includes two horns each having an opening on a larger-diameter side and an opening on a tapered smaller-diameter side opposite to the larger-diameter side, and two corrugated portions provided around the opening on the larger-diameter side of the horn. The outermost corrugated portion is formed to surround all of the horns, and the outermost corrugated portion is formed of one sheet metal member. With this structure, sheet-metal processing can be used to form horns of adaptable shapes and a plurality of horns can be formed at a time.

Abstract: A plane wave antenna including: a horn antenna; a waveguide at least partially inside the horn antenna, wherein the waveguide includes: a central dielectric slab increasing in width toward the horn antenna and with a first dielectric constant, an upper slab above the central dielectric slab with a second dielectric constant, and a lower slab below the central dielectric slab with the second dielectric constant; wherein the central dielectric slab has a substantially constant thickness less than a quarter of a wavelength at a highest frequency of operation of the plane wave antenna.