Abstract: A printed circuit array antenna includes at least one printed circuit formed by a substrate having radiating elements on a first face and an energy distribution tree on a second face. The array antenna is provided with a front structure having an elongated shape and superposed on the first face of the printed circuit. The front structure is composed of a substrate pierced with radiating apertures located opposite to the radiating elements of the printed circuit.

Abstract: The invention is directed to a quadridge antenna situated within a quadri-fluted module. The tips of the ridge elements are recessed a distance below the surface of the window aperture.

Abstract: An array antenna is provided wherein each adjacent pair of a plurality of antenna elements in such array antenna have a common, conductive wall having a castellated radiating edge. Radio frequency energy resistive material is disposed within slots formed in the radiating edge. With such arrangement, electrical coupling between the adjacent pair of antenna elements is reduced thereby improving the gain of the antenna at the lower frequency operating band of the antenna. Further, the electric field distribution is redistributed by the slotted radiating edge from a cosine distribution associated with a linear edge to a more flattened, uniform distribution to increase the effective aperture of the element in the H-plane.

Abstract: A versatile dual band satellite system includes a main conductive mounting plate member with a central opening of a predetermined size, and a KU band pick-up unit mounted in the plate to face a satellite antenna. A dielectric funnel support is mounted on the side of the mounting plate toward the antenna, and includes a central opening of the same size as that in the mounting plate, for receiving a C-band pick-up unit. The system includes appropriate microwave chokes and microwave impedance-matching structure, to improve the rejection of spurious or off-axis signals, and to maximize signal strength at the input of both the KU band and the C-band units. With the mounting openings in the main mounting member and in the dielectric funnel support being identical, full interchangeability of parts is practical, and an initial installation may include the C-band unit mounted in the mounting plate to face the antenna.

Abstract: A dual mode circularly polarized horn radiator is useful in the testing of radiation apparatus in an anechoic chamber. The horn has a buffered radiating aperture which permits a plurality of the horns to be arranged in an array with minimal mutual coupling between the horns. The radiating aperture is located at an end of a conic section, of low flare angle, and has a diameter of one free-space wavelength of the radiation to be radiated from or received at the horn. This permits use of the horn for measurement of near field radiation pattern of apparatus under test. The horn includes an orthomode tee having mutually perpendicular rectangular waveguides extending therefrom, and being coupled thereby to a circular port. A polarizer connects the circular port of the tee to the conic section, and includes two sets of diametrically opposed pins for conversion of both right-hand and left-hand circular polarizations to linearly polarized radiation.

Abstract: A conical horn antenna applicable to plural modes of electromagnetic waves is substantially composed of a feed waveguide positioned on the base end side and feeding a dominant mode of an electromagnetic wave, a conical horn positioned on the fore end side and radiating electromagnetic waves of plural modes including dominant and higher modes, and a desired mode of electromagnetic wave generating portion provided between the feed waveguide and the conical horn and generating an electromagnetic wave of a desired higher mode.

Abstract: An antenna horn of molded plastic construction. The horn may be constructed of multiple sections, each section being of molded plastic construction with the sections joined to form the horn.

Abstract: Doppler radar apparatus for use in a velocity measuring system for farm tractors and the like. The apparatus includes a dual mode conical horn having a flare angle substantially in excess of 12.5.degree., and a dielectric lens formed of a glass filled polymer. The doppler output signal provided by the RF transceiver associated with the dual mode horn is high pass filtered to remove low frequency signals therefrom. The horn is mounted in such a way that it is isolated from mechanical vibrations which would induce doppler signal frequencies in excess of the cutoff frequency of the high pass filter. Moreover, the horn assembly (which is aluminum) and a steel housing assembly are coupled together in such a way that thermal expansion and contraction will not loosen the friction fit between the two assemblies. The two assemblies are held together by a single, large diameter annular locking ring.

Abstract: A feed horn arrangement for reception of C-band and Ku-band signals by a single satellite antenna. The arrangement permits a Ku-band feed horn and amplifier to be mounted at the focus of a satellite dish in addition to the C-band reception equipment. A dielectric rod is mounted within the preexisting C-band waveguide to act as a waveguide to direct Ku-band signals to the Ku-band feed horn and amplifier. The Ku-band dielectric waveguide has no effect on the C-band signals which are amplified by the standard C-band amplifier. The dielectric waveguide may be either straight or curved according to the configuration of the C-band reception equipment.

Abstract: In a high-frequency antenna comprising a plurality of horns 1, phase differences arising in these horns 1 would need to be corrected. Such phase differences are avoided by providing a planar design of the antenna comprising four adjacent horns 1 fed by T-shaped power divider 6, being linear and symmetrical.

Abstract: A horn antenna with a cylindrical and an expanded (horn-shaped) waveguide for radiating or receiving polarized electromagnetic waves. The waveguide wall is partially or wholly covered with one or more grids (12) of electrical conducting material with dielectric layers between them. One possible design consists of a tapering (e.g., conical) core (10) of compact dielectric, which allows for the possibility of shaping the terminal surface (13) to a lens which curves the course of radiation in the aperture to the desired radiation graph. Another possible design where the horn wall consists of dielectric covered with metal grids has an especially light construction. The wall surfaces are developed with anisotrope and reactive impedance so that it mainly functions in the same way as a corrugated horn and thus gives low cross-polarizations across a large frequency area. This could be constructed with little weight and could easily be mass-produced.

Abstract: A vibration isolation and EMI/RFI shielded enclosure for a horn antenna comprises an elongate hollow housing of sufficient dimensions to receive the horn antenna therewithin. Respective front and rear vibration isolation mounting assemblies have inner mounting portions coupled with the horn antenna and outer mounting portions coupled with the housing and resilient vibration damping members coupled intermediate the inner and outer mounting portions. Preferably, an EMI/RFI shielded enclosure is also provided for enclosing electrical circuits associated with the horn antenna.

Abstract: A linearally polarized multiport multimode feed for a reflector type antenna generates a plurality of beams, each in a different pointing direction, from a single radiating aperture. Each beam possesses a distinct phase center determined by the waveguide modes establishing the aperture distribution for that beam. The feed is linear and bilateral, therefore may be utilized in a receiving or transmitting antenna.

Abstract: A device for separating signals in the long or radar wavelength bands from signals in the short or infrared to ultraviolet wavelength bands which occupy a common area. A waveguide for directing radar band wavelengths has apertures in opposing walls of the waveguide, a first of which is rectangular and has a greater length and width than the broadwall dimesnion of the waveguide; and the other of which is circular with a diameter less than one-half the free space wavelength of the long wavelength signal. A pyramidal feedhorn directs the long signal wavelength through the reactangular aperture, where the short-wavelength signal, which also comes down through the feedhorn passes through the second aperture. The long-wavelength component instead of passing through the second aperture is deflected into the waveguide.

Abstract: A polarized signal receiver waveguide assembly, or feedhorn, for receiving a selected one of linearly polarized electromagnetic signals in one waveguide of circular cross-section and for launching or transmitting the selected signal into a second waveguide, the axes of the waveguides being disposed at right angle. The first waveguide has a closed end wall, formed as a hemispherical cavity having a hemispherical concave surface. A probe comprising a signal receiver portion disposed in a plane perpendicular to the axis of the first waveguide and a launch or re-transmitter portion having its axis perpendicular to the axis of the second waveguide has its launch or transmitter portion mounted in a controllably rotatable dielectric rod, such that rotation of the rod causes rotation of the signal receiver portion for alignment with a selected one of the polarized signals.

Abstract: An array of horn antennas with non-uniform aperture sizes is disclosed wherein the individual horns phase track over a wide frequency band. The horn with the smallest aperture is considered the reference horn, and its length defines the overall horn length of the other horn in the array. The flare lengths of the other horns of the array are less than the length of the reference horn, and lengths of waveguide are added to the other horns such that the respective combined flare lengths and waveguide lengths of each of the other horns equals the horn length of the reference horn. The respective lengths of the flare and the waveguide section are chosen such that the resultant horn antenna phase tracks the reference horn over the frequency band.

Abstract: A polarized signal receiver waveguide assembly, or feedhorn, for receiving a selected one of linearly polarized electromagnetic signals in one waveguide of circular cross-section and for launching or transmitting the selected signal into a second waveguide, the axes of the waveguides being disposed at right angle. The first waveguide has a closed end wall, either flat or, alternatively, formed as a hemispherical cavity having a hemispherical concave surface. A probe comprising a signal receiver portion disposed in a plane perpendicular to the axis of the first waveguide and a launch or transmitter portion having its axis perpendicular to the axis of the second waveguide has its launch or transmitter portion mounted in a controllably rotatable dielectric rod, such that rotation of the rod causes rotation of the signal receiver portion for alignment with a selected one of the polarized signals.

Abstract: An antenna selectively fed from a square waveguide in one of two orthogonal linear TE.sub.1,0 modes includes a transition between the square waveguide and a larger square horn. A transition arrangement including a plurality of thin conductive elements or vanes is dimensioned and located at the transition to provide a gradual transition between the smaller waveguide dimension and the larger horn dimension in the E plane, and an abrupt transition in the H plane, regardless of the polarization selected. The abrupt transition in the H plane converts some of the TE.sub.1,0 mode energy to the TE.sub.3,0 mode. The radiating aperture is at a predetermined distance from the transition arrangement so that the desired relative phase between the TE.sub.1,0 and TE.sub.3,0 modes may be established. The E-plane aperture distribution is unaffected by the phasing, but the H-plane aperture distribution can be controlled by selection of the appropriate relative phase in order to provide a more linear distribution than TE.sub.

Abstract: An array of flared horn antennas is adapted to be fed from circular waveguide. The apertures of the horns are closely spaced. Prior art horns with circular apertures leave gaps in the aperture. The gaps are eliminated, and the gain of the array is increased by about 1/2 dB by tapering the horns from a circular cross-section at the feed end to a hexagonal cross-section at the radiating aperture end.

Abstract: A polarized signal receiver waveguide assembly, or feedhorn, for receiving a selected one of linearly polarized electromagnetic signals in one waveguide of circular cross-section and for launching or transmitting the selected signal into a second waveguide of rectangular cross-section, the axes of the waveguides being disposed at right angle. A probe comprising a signal receiver portion disposed in a plane perpendicular to the axis of the first waveguide and a launch or transmitter portion having its axis perpendicular to the axis of the second waveguide has its launch or transmitter portion mounted in a controllably rotatable dielectric rod, such that rotation of the rod causes rotation of the signal receiver portion for alignment with a selected one of the polarized signals. The transmission line between the probe signal receiver portion and launch or transmitter portion consists of a pair of bifurcated branches forming a rectangle disposed along the axis of the first waveguide.

Abstract: A high-frequency antenna unit module for receiving or transmitting a rectilinearly polarized wave including radiating elements in the form of horns and a waveguide supply network. The module has four horns with square apertures which form a bidimensional network in a plane parallel to a reference plane P. The supply network is of the "planar" type having first pairs of opposing sidewalls extending in a direction parallel to P, and of the "tree-structured" type because all of the horns are fed in-phase by T-shaped power dividers. The waveguide sections have sidewall dimensions a and b, where a>b and a=.lambda..sub.c /2. The dimension b is the width of each of the opposing sidewalls extending parallel to P, and a is the height of opposing sidewalls extending perpendicularly to P and connecting each of the first pairs of sidewalls. The network is suitable for propagating the TE.sub.01 mode along which the electric field vector E propagates in parallel with the plane P.

Abstract: A dual frequency antenna feed includes colinear axially spaced coaxial and circular waveguide cavities separated by a conducting portion having a high frequency rectangular waveguide therein extending radially outward. The coaxial cavity includes a tubular inner conductor having a polarization rotator connected to the rectangular waveguide for propagating high frequency energy. Four small coaxial transmission lines equiangularly disposed about the cavity axes and terminating in probes about a quarter wavelength from the end of each cavity intercouples the circular and coaxial cavities. The end of the coaxial waveguide cavity forms an aperture for high frequency energy from the conducting inner tube and for the low frequency energy from the region between the conducting inner tube and the cylinder surrounding the outside of the cavity. The radiating aperture is surrounded by a set of concentric conducting rings.

Abstract: Antenna horns for use as part of antenna system such as an offset parabolic antenna system. The horns of this antenna include a plurality of sections which enable the propagation of both the TE.sub.1,1 mode and the TM.sub.1,1 mode.

Abstract: This invention relates to rotatable antenna feed polarizers for use in communication antenna systems, and seeks to provide, at economic cost, an antenna feed polarizer which is capable of being rotated accurately.The polarizer is rotated by a threaded member rotated by a motor. A drive member is moved longitudinally by the rotation of the threaded member. Two flexible connectors are each attached at one end to the drive member, pass around idler wheels, are wrapped partly around the polarizer, and are fixed to the latter. Movement of the drive member pulls one of the flexible connectors and thereby rotates the polarizer.Backlash is minimal because it occurs between only two moving parts, the drive member and the elongate member, and is achieved without using gears with minimum backlash, which may be expensive.

Abstract: An antenna feed structure for use with a parabolic reflector in amplitude-comparison monopulse radar applications employs a dedicated transmit feed centered within a four-port receive array of conventional element spacing to eliminate the need for a circulator or other transmit/receive device while retaining satisfactory receive array performance. Isolation pins placed around the transmit port act to decouple it from the receive ports, and a double waveguide run to the transmit port reduces uneven heating and related phase imbalance in adjacent receive waveguide runs.

Abstract: A circularly polarizing antenna feed comprises a feed waveguide having a short circuit reflecting plate at one end and a radiating horn at the other, a wave exciter for launching linearly polarized plane waves axially along the feed waveguide in opposite directions, and a grid of parallel reflector strips disposed in a plane which is perpendicular to the waveguide axis and which is located between the wave exciter and the reflecting termination at a distance of approximately .lambda.g/8 from the exciter and approximately .lambda.g/4 from the termination. The reflecting strips of the grid are inclined at an angle of 45.degree. to the direction of polarization of the waves propagated by the exciter, the grid and the reflecting termination together forming a twist reflector which effectively reflects and rotates through 90.degree. the waves incident upon the grid. These reflected waves together with the forwardly propagated waves from the exciter represent circularly polarized waves.

Abstract: A directive antenna (for a groundstation or a satellite) has a plurality of discrete receptional states which provide predetermined electronic displacements from boresight of the optimum direction of reception. The direction of the target is obtained by rapid switching from one receptional mode to another. The receptional modes are preferably provided by switchable mode converters, e.g. 6A, 6B, 7A and 7B, which are coupled with the waveguide so as to convert higher order propagation modes, e.g. TM01, TE21(H) and TE21(V), to the fundamental.

Abstract: A waveguide-fed horn structure includes a constraining mechanism having an extremely high degree of dimensional stability over a wide thermal range. The constraining mechanism comprises a composite graphite honeycomb structure that forms a support backing for the waveguide feed and for the conductive surface sections of the horn radiator. The conductive surface of the horn radiator is supported on a first section of graphite epoxy laminate while a second section of graphite epoxy laminate supports the honeycomb backing and is bonded to the first section of laminate, thereby effectively surrounding the feed-horn structure with a thermally tolerant, physical distortion constraining support.

Abstract: A horn antenna is supported by a pair of axially spaced apart trunion assemblies which are rigidly attached to the upper one of a pair of nested ring shaped members, the lower ring member being rigidly attached to a platform. Flat ring shaped flanges on the tops of the members are in contact for rotatably supporting the upper ring member in the lower ring member. Rotation of the antenna is accomplished with a turnbuckle that is connected between the perimeters of the two flanges. Each trunion assembly comprises a bolt that is welded to the top of the upper flange and that has a nut thereon supporting one side of the antenna. Elevation adjustment of the antenna is accomplished by threading the nut on the trunion bolt for raising or lowering the associated side of the antenna.

Abstract: A device for receiving dual polarized microwave signals, including a first waveguide connected to a receiving antenna and to a first substrate bearing a first sensor perpendicular to the longitudinal axis of the first waveguide, a second waveguide having the same longitudinal axis and the same dimensions as the first waveguide, and which is connected to a second substrate having a second sensor perpendicular to the longitudinal axis of the second waveguide. Surrounding the second waveguide is a tube having tongues at opposed ends which cooperate with slots formed in the first and second substrates. The opposed tongues of the tube are staggered by 90.degree. so that upon insertion of the opposed tongues of the tube within the slots of the first and second substrates, sensors formed on these substrates are arranged orthogonally with respect to one another. The tongues and cooperating slots assure mechanical integrity.

Abstract: A reflector antenna is disclosed which generates two or more beams which are separated angularly in the elevation plane, as in multi-beam antennas, and are shaped so as to provide, when combined, any desired pattern of coverage. The antenna includes a horn which receives separated inputs and radiates toward a reflector primary beams displaced from one another by a predetermined angle but having a single phase center.

Abstract: An overmoded waveguide transition comprises a flared waveguide section having different transverse cross-sections at opposite ends thereof, the longitudinal shape of a section of the transition adjacent an end thereof being defined by the equation:(r.sup.p /a)-(l.sup.p /b)=1where a and b are constants, r is the radius of the transition, l is the axial distance along the transition measured from one end, and the exponent p has a value greater than two.

Abstract: A primary radiator for circularly polarized wave in accordance with the present invention is equipped with conductor projections along the inner wall of the horn antenna in order to convert linearly polarized wave to circularly polarized wave within the horn antenna, without adapting the prior art generator of circularly polarized wave. Consequently, it becomes possible to reduce the axial length and the overall size of the radiator. Moreover, the conductor projections are constructed with their edge sections on the aperture end side of the horn antenna sloping down along the inner wall of the horn antenna, so that generation of higher order modes can be suppressed and a satisfactory directivity can be obtained.

Abstract: A horn radiator with a grooved inner surface has a mode coupler for a TE.sub.01 wave and includes four cavity resonators embedded in the grooved surface of the horn and interconnected by an annular rectangular wave guide extending around the outer surface of the horn.

Abstract: A corrugated elliptical waveguide medium comprises a corrugated hybrid mode excitation member having an elliptical transverse cross-section for propagating electromagnetic energy therethrough. The excitation member is provided with longitudinally spaced apart parallel corrugations with the teeth of the corrugations defining an inner ellipse and the grooves of the corrugations defining an outer ellipse. The depths of the corrugation grooves on the major and minor axes of the ellipsis are dimensioned such that the tangential electric and magnetic field components of the energy in a circumferential direction are zero on the inner ellipse.

Abstract: A compact adaptor is provided for making transition from ridged waveguide to rectangular waveguide while simultaneously imparting spatial reorientation of associated electric and magnetic fields. The adaptor is especially useful for feeding a phased array of radiating slots (or other structures) where adjacent radiating structures are preferably spaced from one another on the order of a half wavelength and fed with the magnetic field vectors oriented parallel to such inter-element array spacing dimensions. In the exemplary embodiment, a transition from double-ridged waveguide to rectangular waveguide is effected through an electrically short (e.g., 1/8th to 1/4th wavelength) non-resonant cavity using oppositely tapered continuations of the ridged waveguide walls (acting as a TEM parallel transmission line) to opposing walls of a rectangular waveguide port which is spatially oriented transverse to the ridged waveguide.

Abstract: A radio frequency antenna is provided comprising: a waveguide section; first means for establishing radio frequency energy in such waveguide section having a first linear polarization with an electric field disposed normal to opposing wide walls of the waveguide section; a planar microwave circuit means, for establishing a second linear polarization having an electric field disposed perpendicular to the electric field of the first linear polarization, such microwave circuit means being disposed within the waveguide between the wide walls and relative to the feed means to provide the first linear polarization and the second linear polarization with substantially coincident phase centers. In a preferred embodiment of the invention, the microwave circuit means includes a strip conductor feed separated from a ground plane conductor by a dielectric, such ground plane conductor having a notch formed therein and fed by the strip conductor.

Abstract: A polarized signal receiver waveguide assembly, or feedhorn, for receiving a selected one of linearly polarized electromagnetic signals in one waveguide of circular cross-section and for launching or transmitting the selected signal into a second waveguide, the axes of the waveguides being disposed at a right angle. The first waveguide has a closed end wall, formed as a hemispherical cavity having a hemispherical concave surface. A probe comprising a signal receiver portion disposed in a plane perpendicular to the axis of the first waveguide and a launch or transmitter portion having its axis perpendicular to the axis of the second waveguide has its launch or transmitter portion mounted in a controllably rotatable dielectric rod, such that rotation of the rod causes rotation of the signal receiver portion for alignment with a selected one of the polarized signals.

Abstract: A wide-band microwave antenna capable of radiating over a wide angular field is fed by a rectangular wave guide and includes a first sectoral horn coupled to the rectangular wave guide. The first sectoral horn is sectoral in the H plane. Coupled to the first sectoral horn is a second sectoral horn which is sectoral in the E plane. The second sectoral horn has a partial-cylindrical-shape with circular-shaped outer edges. The second sectoral horn has a top plate and a bottom plate. A plurality of equally spaced power distributors are radially disposed in the second sectoral horn and extend from the top plate to the bottom plate through the entire length of the second sectoral horn. These power distributors thus form a plurality of elementary radiation sources.

Abstract: A microwave polarization converter for converting circular polarization to linear polarization or vice versa. The converter includes a fin and a shorting plate to effect such conversion.

Abstract: Doppler radar apparatus for use in a velocity measuring system for farm tractors and the like. The apparatus includes a dual mode conical horn having a flare angle substantially in excess of 12.5.degree., and a dielectric lens formed of a glass filled polymer. The doppler output signal provided by the RF transceiver associated with the dual mode horn is high pass filtered to remove low frequency signals therefrom. The horn is mounted in such a way that it is isolated from mechanical vibrations which would induce doppler signal frequencies in excess of the cutoff frequency of the high pass filter. Moreover, the horn assembly (which is aluminum) and a steel housing assembly are coupled together in such a way that thermal expansion and contraction will not loosen the friction fit between the two assemblies. The two assemblies are held together by a single, large diameter annular locking ring.

Abstract: A radio frequency antenna element is provided comprising a waveguide having disposed within and adjacent to a rearward portion of such waveguide a ridge, such ridge having a relatively narrow forward portion and a plurality of feeds, disposed within the waveguide, for coupling energy from a plurality of sources to a relatively wider, rearward portion of the ridge. The waveguide has a pair of opposing, relatively wide upper and lower walls and a pair of opposing, relatively narrow side walls. The relatively wider, rearward portion of the ridge tapers to the narrower forward portion of the ridge in a plane parallel to the upper and lower walls of the waveguide. The narrow portion of the ridge tapers towards one of the wider walls as such ridge extends from the rearward portion of the waveguide to the forward portion of the waveguide.

Abstract: A low cost tapered horn with desirable equal E and H plane pattern beamwidths is achieved with one or more annular channels in the tapered wave translation surfaces of the horn. These channels extend concentric and parallel with the axis of symmetry of the horn to permit the horn including the channels capable of being formed using molding techniques.

Abstract: Antenna output for a planar antenna comprising an array of receiving elements provided by two networks (20, 30) of high frequency transmission lines and three sheets (10, 40, 50). The first sheet (10) comprises first cavities (11), the first and second transmission line networks are planar, located respectively on either side of this first sheet and, for signal reception, coupled to each of the cavities by a corresponding number of distinct ends forming exciting probes along two perpendicular axes. The third and second sheets (40, 50) are located on the other side of both of these networks and comprise second and third cavities (41, 51) which are in line with the first cavities. The third cavities are short-circuited in a plane parallel to the surfaces of the sheets, and these sheets are made of a metal or of a dielectric material having metal-plated walls of the cavities.

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: A horn antenna suitable for an amplitude-comparison broadband direction-finding system with 360.degree. azimuth coverage comprises a horn with a wide angle of flare in a plane normal to the z-axis of a cylindrical co-ordinate system and an aperture which is suitably cylindrical, as seen from that axis, and further comprises means for launching electromagnetic energy into the horn towards the aperture. In order to provide a substantially constant beamwidth over a broad frequency range, which may be as wide as 7:1, the horn and launching means are adapted to launch and propagate to the aperture a substantially pure lowest order circumferential mode having its electric field in a direction parallel to the z-axis, the launching means acting substantially as a line source coincident with the z-axis. The flare angle may be 180 degrees, and the launching means may comprise an electric probe extending substantially along the z-axis.

Abstract: A four-port network which is connected to a microwave antenna feed horn for separating four signal paths associated, in pairs, with two polarizations and two frequency bands, and with the network also being utilized for the derivation of antenna tracking signals according to the monopulse principle. A conductor is disposed along the longitudinal axis of the waveguide connecting the antenna feed horn with the four-port network, with this conductor extending, on the one hand, to the region of the antenna feed horn throat and, on the other hand, into the four-port network so as to couple in signals of a higher order mode for the derivation of the antenna deviation signals.

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: Current-flow is suppressed on the outer surface of the horn except in a small endmost region. A reflector surrounds the horn, spaced rearwardly from the mouth. A choke used for the suppression blocks current-flow between the horn and the reflector. A high degree of uniformity of the radiation pattern over a wide forward angle is achieved.

Abstract: A rotatable polarized signal receiver in a system for receiving linearly polarized electromagnetic signals includes a signal conductor having a receiver probe portion, oriented in a circular waveguide parallel to the polarization of the incident signal, and signal launch probe portion extending into the rectangular waveguide orthogonal to the direction of signal transmission therein, mounted concentrically in an insulator rod through perpendicular coupling of the circular and rectangular waveguides.