Abstract: This radiating slot array antenna is made out of a printed circuit sandwich structure with: a radiating plate in printed circuit form transparent to microwaves having, on its upper face, a metallization plane in which there are etched alignments of radiating slots; chutes made of a plastic material with a metallized inner wall, the chutes having their hollow part before the upper face of the radiating plate, being soldered by their edges to the metallization plane of the upper face of the radiating plate on and parallel to the alignments of radiating slots so as to overlap them, and reconstituting the three missing walls of waveguides whose fourth wall is constituted by the metallization plane etched with radiating slots of the upper face of the radiating plate; and an upper plate assembled on the back of the chutes to ensure the stiffness of the antenna. Its composition as a sandwich of printed circuits gives it high rigidity, great lightness and a low cost price.

Abstract: The present invention relates to a device at an antenna for eliminating grid lobes in the radar cross section of the antenna.The invention displaces the grid lobes to a frequency range outside the working frequency of the antenna by inserting rows of dummy elements (r.sub.3, r.sub.4, r.sub.5) between rows of ordinary antenna elements (r.sub.1, r.sub.2) in the antenna (11). The dummy elements will behave like the ordinary antenna elements (15) as regards the rescattering when the dummy elements (17) are irradiated with signals from outside. Furthermore, the dummy elements (17) are not fed by a feeding network (16a, 16b) with microwave signals as is the case with the ordinary antenna elements (15). The dummy elements (17) are arranged in the rows of dummy elements (r.sub.3, r.sub.4, r.sub.5) so that the distances in X-direction and in Y-direction (a.sub.4, a.sub.5, a.sub.6, a.sub.7, a.sub.

Abstract: A leaky waveguide antenna array that receives and/or transmits electromagnetic signals includes a plurality of radiation waveguides disposed in parallel to each other on a surface plane to form the antenna array. A feed waveguide is located below the surface plane and provides an electromagnetic signal to the plurality of radiation waveguides and/or receives a plurality of electromagnetic signals from the plurality of radiation waveguides and provides a composite electromagnetic signal at an output of the feed waveguide. Each of the plurality of radiation waveguides has a waveguide axis and includes a plurality of apertures arranged in a direction of the waveguide axis. The feed waveguide includes a first section of waveguide having a first end connected to an input/output port. The first section of waveguide has a height substantially the same as the height of each of the plurality of radiation waveguides and the first section of waveguide has a second end coupled to a first junction point.

Abstract: A ferrite scanning line source is formed of a ferrite toroid and one or more dielectric slabs mounted to a side of the toroid. A signal propagating through the waveguide is phase shifted by the magnetization of the toroid. The further down the toroid the signal propagates the greater the phase shift that is applied to the signal. Radiators or coupling ports are formed by slots cut in a wall of the waveguide. The phase of the signal radiating from each slot in the line source is shifted from the signals emanating from the preceding and following slot in the line source. By properly locating the slots along the line source, a composite beam formed by the energy radiating from each slot may be titled (scanned) to a desired direction. In addition, the amount of phase shift applied to the signal by the waveguide depends on the magnetic state of the phase shifter.

Abstract: A flat antenna array includes a screen plate, a conductive aperture plate which overlies the screen plate, and a dielectric sheet which is located between the aperture plate and the screen plate. Apertures in the screen plate define the locations of waveguides. A network of conductors is carried on the dielectric sheet. The conductors include stimulating elements which are aligned with the apertures. Each stimulating element includes first and second probes which have axes which cross each other and constitute a probe pair. A plurality of reflective elements are located above the dielectric sheet at locations which correspond to the apertures. A first output circuit connects together the first probes, a second output circuit connects together the second probes.

Abstract: An antenna design includes a plurality of radiating elements which radiate electro-magnetic energy, and feeders which feed the electromagnetic energy to the radiating elements. The feeders have a supply network substantially at the same level in the antenna thickness direction. In order to achieve a small antenna with adequate properties for radio link usage, the radiating elements are arranged next to the supply network in the thickness direction and include box horn antennas which have a step, characteristic of a box horn, in the plane of the magnetic field.

Abstract: A coaxial resonant slot antenna having a novel structure is provided to further reduce the dimensions of radio terminals incorporating such an antenna. Also provided are a novel method of fabricating such a coaxial resonant slot antenna and a radio terminal having a novel structure using such a coaxial resonant slot antenna. An entire strip conductor is arranged inside a flat conductive cubic such that the strip conductor is insulated from the conductive cubic. A connection point between the strip conductor and a radio frequency transmission line is provided at a position about 1/4 of wavelength away from one end of the strip conductor. A slot is shaped into a narrow rectangle, a generally upside-down "U", or a generally upside-down "U" having another slot on each end. It is desired that the center slot crosses the strip conductor along the length thereof and in the height direction thereof, the distance between the ends being equivalent to about 1/2 of wavelength used.

Abstract: An integrated multi-band and multi-polarization antenna array comprising: a plurality of first waveguides located in spaced parallel relationship, the waveguides being dimensioned so as to carry signals of a first wavelength, the waveguides containing slots in a first surface so as to radiate the signals carried by the first waveguides with horizontal polarization, a plurality of second waveguides located in spaced parallel relationship to each other and to the first waveguides, and bridging and abutting the first waveguides adjacent a second surface opposite the first surface, the second waveguides being dimensioned to carry signals of the first wavelength, the second waveguides containing slots in a surface parallel to the first surface so as to radiate signals carried by the second waveguides with vertical polarization, a third waveguide located in spaced parallel relationship to the first and second waveguides, dimensioned to carry signals of a second wavelength, and containing slots in a surface parallel

Abstract: A compact high gain VHF antenna for airborne synthetic aperture radar to detect targets concealed behind trees and forests. The antenna is formed by cutting a slotline in the middle of the top wall of a very thin waveguide along its axis. The waveguide can be folded and mounted on the underside of the wings of an aircraft with minimum protrusion and wing drag. The antenna produces a downward and side-looking beam with horizontal polarization for maximum foliage penetration and target detection. The antenna design can be scaled to any frequency for ground based and shipboard applications.

Abstract: A slot antenna has a generally cylindrical waveguide and a feed end. A plurality of slots are formed in the waveguide. A plurality of feed strips are secured to the feed end and are secured to the waveguide in spaced apart relationship from the outer surface of the waveguide. Exciters are in communication with the feed strips and extend over the slots.

Abstract: A waveguide antenna includes a number of longitudinal waveguides with lateral and longitudinal slots arranged to emit electromagnetic fields with separate directions of polarization. The waveguide antenna includes a first waveguide having a first rectangular cross-section with lateral slots at substantially right angles with respect to the longitudinal axis of the first waveguide. The lateral slots are arranged in a first short side of the first waveguide. The waveguide antenna also includes a second waveguide having a second rectangular cross-section with longitudinal slots arranged in a second short side at substantially right angles with respect to the lateral slots, and a separating wall. The first and second waveguides are joined at respective first and second broad sides with the first and second short sides facing the same direction.

Abstract: A dual band monopulse radar antenna has a planar configuration and is divided into four quadrants. The antenna includes a circular plate with an array of slots formed in each quadrant. The slots are configured for operation at a first frequency, such as X-band. Four respective slot waveguide feeds are provided, one for each array of slots in each quadrant. A dielectric layer, such as Teflon, is mounted on the surface of the plate. Each quadrant of the antenna is provided with an array of microwave patch elements comprising a plurality of rows of patch elements fed by a microstrip line. Each array of microwave patch elements is fed by a waveguide. The antenna has eight waveguide couplers, two for each quadrant of the antenna with one waveguide feed in each quadrant for the slot array and one waveguide coupler in each array for the microwave patch element array.

Abstract: A leakage dielectric waveguide includes a housing made of plane-shaped electrical conductors located parallel to each other, and a dielectric strip for propagating a high-frequency wave between the parallel electrical conductors, wherein the dielectric strip is provided within the housing. The housing is arranged to be asymmetrical, thereby leaking and radiating a high-frequency wave propagating through the dielectric strip. The housing is preferably further composed of the plane-shaped parallel electrical conductors and a side wall. A plane antenna includes the above-mentioned leakage dielectric waveguide, and a projecting device for projecting the high-frequency wave toward a free space in response to a high-frequency wave being projected from the dielectric waveguide.

Abstract: A slotted leaky waveguide array antenna comprises a flat, thin bottom plate made of a metallic material; a flat, thin slotted plate made of a metallic material, and disposed parallel with the bottom plate at a predetermined distance from the bottom plate to form a space between the slotted plate and the bottom plate, the slotted plate being formed with a plurality of slots arranged in substantially parallel rows extending in a predetermined guide axial direction; a plurality of flat, thin side walls made of a metallic material and arranged in the space so as to partition the space between the bottom plate and the slotted plate into a plurality of waveguides communicating with each other and including radiation waveguides extending in parallel in the guide axial direction, a lower surface of each of the side walls being fixed to the bottom plate and an upper surface thereof being fixed to the slotted plate; and an electrically conductive adhesive agent layer between the upper surface of each of the side walls

Abstract: A radiating waveguide comprises an elongated waveguide with a transverse cross-section dimensioned to carry only the dominant mode at a selected operating frequency. One wall of the waveguide forms a continuous non-resonant longitudinal slot or equivalent thereof to produce a radiated field polarized perpendicularly to the slot. The slot extends substantially parallel to the axis of the waveguide and has a transverse dimension that is sufficiently narrow to substantially avoid the radiation of a field polarized parallel to the slot.

Abstract: There is provided a small-sized and simplified horizontally polarized antenna apparatus which forms an omnidirectional pattern in the horizontal plane. The radiation field in the horizontal plane becomes continuous and a horizontally polarized omnidirectional radiation pattern can be obtained in the horizontal plane by forming radiation slots at opposing positions on a grounded hollow body and exciting the slots out of phase.

Abstract: Array antenna has a number of radiating elements and is provided with an arrangement to reduce the reflection of the incident radiation in a direction opposite to that of the incident radiation. The arrangement includes electrically conducting elements which are located between the radiating elements and substantially parallel to the electrical field of the radiating elements.

Abstract: The line comprises a tubular outer conductor including apertures configured to form a periodic pattern (M) repeated along said outer conductor with a predetermined pitch (p). The periodic pattern has a length (L) equal to p/2.+-..DELTA., along a direction parallel to the axial direction of the line. The periodic pattern can be produced in various embodiments.

Abstract: A polarization-universal radial line slot antenna has a slot plate formed with numerous slots, a frame, and a partition plate interposed between the slot plate and the frame to form an upper layer waveguide and a lower layer waveguide. A pair of first and second feeding devices are provided in a central portion of the antenna. The first feeding device has a first matching member protruding into the upper layer waveguide for feeding thereto a radio wave diverging from a center to a periphery so that a left-hand circular polarized wave is emitted from the slots. The second feeding device has a second matching member for feeding a radio wave which passes through the lower layer waveguide and then converges from a periphery to a center of the upper layer waveguide so that a right-hand circular polarized wave is emitted from the slots. Consequently, the single antenna can concurrently transmit or receive the right-hand and left-hand circular polarized waves.

Abstract: A centered longitudinal series/series coupling slot disposed between a boxed stripline and a crossed rectangular waveguide comprising a plurality of longitudinal radiating slots. The centered longitudinal series/series coupling slot is disposed orthogonal to the longitudinal radiating slots of the crossed rectangular waveguide. The centered longitudinal series/series coupling slot is longitudinally disposed along the centerline of the boxed stripline in such a way the centered longitudinal slot interacts with the stripline mode and not with the rectangular waveguide mode (TE.sub.10 mode) in the boxed stripline. As a result of this, a highly efficient standing wave (or travelling wave) feed is provided using the centered longitudinal series/series coupling slot in the boxed stripline.

Abstract: A scanning array antenna employs a solid rotating core having an anisotropic refractive index within an apertured waveguide that emits radiation in response to an input beam propagating through the waveguide. Rotating the core changes its refractive index relative to the input beam, causing the radiated beams to undergo an angular scanning. The solid rotating waveguide core can be formed from a dispersion of aligned elongate conductive members in an isotropic dielectric, from a liquid crystal medium, or from a dispersion of aligned elongate conductive members in a liquid crystal medium. The antenna is operable in reciprocal transmission and reception modes.

Abstract: A slotted waveguide array antenna includes a plurality of waveguide elements extending in a parallel side-by-side relation, each having a radiating side including a broad wall formed with a plurality of slots, and an asymmetric ridge. The slots are slanted to the longitudinal axis of the antenna in alternating directions and are spaced .lambda.g/2 apart such as to offset phase reversal between each pair of adjacent slots.

Abstract: A scanning folded lens antenna system for scanning reception and/or transmission of electromagnetic radiation and method of scanning receiving and/or transmitting electromagnetic energy. The folded lens has a first cylindrical parallel plate waveguide, a second cylindrical parallel plate waveguide, a waveguide coupler operatively associated with the first and second waveguides to communicate a signal therebetween so as to transform a cylindrical signal from the first waveguide to a substantially planar phase signal in the second waveguide, and a plurality of coupling device operatively associated with first waveguide for coupling a signal between the first waveguide and the coupling device.

Abstract: A common aperture dual polarization array that comprises a vertical polarization antenna array that provides for vertical polarization, and horizontal polarization antenna array that provides for horizontal polarization. The vertical polarization antenna array is comprised of a flat plate shunt slot standing wave array that includes a plurality of sets of radiating slots configured in a staggered pattern that are laterally separated by an air gap. The horizontal polarization antenna array is comprised of a collinear array of radiating slots, a strip reflector, and a plurality of baffles that form a short backfire antenna array. The collinear slots are disposed orthogonal to the radiating slots of the vertical polarization antenna array.

Abstract: Microwave devices incorporate at least one photosensitive baffle that is selectively illuminated changing the baffle's electronic characteristic from being transparent to being reflective of microwave energy. The baffle serves as a gate, tuning element, reflector and the like. Various forms of photosensitive baffles and microwave devices are presented.

Abstract: A unitary waveguide element is employed in a light weight waveguide antenna. The waveguide element has a waveguide portion having a front wall with slots formed across it at predetermined locations, a continuous back wall, and substantially continuous broad walls. A first flange is formed on one of the broad walls lying in a plane that extends in the width direction. A pair of flanges are formed on the other broad wall that lie in planes that are displaced slightly from the first flange, so that when the waveguide element is superposed onto the next successive element, these flanges overlap with the second flanges straddling the first flange. The flanges are then bonded with epoxy or an equivalent agent. A rivet box is formed on the proximal side of the back wall and permits attachment of the waveguide element in precise alignment to a predrilled backing plate with rivets or other suitable fasteners. The rivets do not penetrate into the waveguide portion of the element.

Abstract: A slotted leaky waveguide array antenna of a one-axis tracking type wherein a feed section including a feed probe is kept in a stationary state to thereby keep a converter in a stationary state and a desired beam width is set in a tilt direction, includes a plurality of radiation waveguides arranged adjacent and parallel to each other, each of which has a plurality of slots arranged in a waveguide axial direction, and a feed waveguide for distributing to the respective radiation waveguides electromagnetic waves received through a feed section from a converter, and the antenna rotates in a substantially horizontal plane to track an azimuth direction, wherein the feed waveguide has a first section extended along one ends of the radiation waveguides and a second section extended from the feed section provided in the rotary center of the slotted leaky waveguide array antenna to the center of the first section, and wherein the radiation waveguides are formed with crossed slots having an identical offset, and the n

Abstract: A traveling-wave feeder type coaxial slot antenna, comprising: a central conductor extending over a certain length; a cylindrical outer conductor coaxially surrounding the central conductor; and a plurality of slots provided in the outer conductor at a certain inclination angle, for instance 45 degrees, relative to a longitudinal axis of the outer conductor. This antenna can be conveniently fabricated from a commercially available coaxial cable. By suitable selection of the inclination angle of the slots and their mutual spacing, the antenna may be provided with a directivity directed to a desired elevation angle when mounted on a vertical wall to make is suitable for receiving radio wave signals from a satellite.

Abstract: A dual polarization array that comprises horizontal polarization and vertical polarization arrays, combined with an efficient waveguide-fed standing wave feed array. The vertical polarization array comprises an offset, resonant, iris-fed, centered longitudinal-shunt-slot, standing wave array. The horizontal polarization array comprises a flared dipole fed by a longitudinal, shunt-slot, standing wave array. The waveguide-fed standing wave feed array is comprised of a plurality of waveguides that separately feed the horizontal polarization and vertical polarization arrays. The horizontal polarization array comprises a first plurality of radiating waveguides laterally disposed adjacent to each other that are separated by a first plurality of gaps. Each waveguide comprises a plurality of radiating flared dipoles disposed adjacent to a respective plurality of longitudinal radiating shunt slots.

Abstract: A waveguide antenna (1) has an upper (2) and air (3) cavity waveguide, these waveguides being separated by a partition wall (4). Transversely extending slots (7) are disposed along the center line of the upper waveguide (2) with a mutual spacing of one wavelength-distance (.lambda..sub.g). Two slots (6) which extend in the direction of the longitudinal axis of the waveguide are disposed between the transversal slots (7). The partition wall (4) is provided with longitudinally extending slots (8) immediately beneath the longitudinally extending slots (6), and field-shifting posts (9) are placed in the lower waveguide (3) adjacent the latter slots (8) in a zig-zag pattern along the waveguide (3). Baffles (10) counteract grating lobes. A fundamental mode of an electromagnetic field (E1) in the upper waveguide (2) excites only the transversal slots (7), which radiate a field (E3). The same fundamental mode (E2) in the lower waveguide (3) excites the slots (8) in the partition wall.

Abstract: There is provided an improved planar antenna, for use in satellite communication, capable of providing higher aperture efficiency, improved circular polarization and increased production tolerability. The antenna comprises a waveguide and an array of M.times.N helical antenna elements, wherein M and N are integers.

Abstract: An anti-ice radome having a frequency selective surface and a plurality of resistive heating elements is disclosed. The frequency selective surface prevents the resistive heating elements from disturbing the electromagnetic waves generated by an antenna within the radome. Thus, ice formation on the radome can be prevented without sacrificing the transmission characteristics of the radome.

Abstract: A radiating tapered notch antenna (sometimes known as a Vivaldi antenna) is fed by a section of slotline, which in, turn is fed by a coplanar waveguide. The transition from the unbalanced coplanar waveguide to the balanced slotline is accomplished by an infinite balun, where the center conductor of the coplanar waveguide terminates on the slotline conductor opposite the ground conductor of the coplanar waveguide. One slot of the coplanar waveguide becomes the feeding slotline for the notch, and the other slot terminates in a slotline open circuit. All of the elements of the system are coplanar.

Abstract: This plane array antenna for receiving satellite broadcasts is an optimal combination of the plane array antenna main body having a tilt angle, a converter connected with the antenna main body through the power supply portion, and the rotation mechanism for rotating the antenna main body within almost a horizontal plane for tracking the azimuthal angle direction. The plane array antenna main body has the power supply portion formed at the center of the rotation and the converter includes a dielectric substrate having a microstrip channel formed on the substrate and a casing accommodating the substrate. The converter is fixed downwardly of the antenna main body and supports the antenna main body. The power supply portion includes the power supply probe with an insulation covering, and has its front end portion inserted into a space formed with the antenna body, a central portion extending through the casing of the converter, and the lowest end portion combined with the microstrip channel.

Abstract: An antenna for transmitting rf energy. A polarizer for selectively polarizing the rf energy is operatively connected to a longitudinal shunt slotted plate for radiating rf energy therethrough. A rotational series slotted plate is operatively connected to the longitudinal shunt slotted plate for feeding the rf energy thereto. The plate has slots arranged in columns. First and second dual end slot array feeds are operatively connected to first and second columns of series slots of the rotational series slotted plate, said feeds having first and second input tee junctions. A manifold is operatively connected to the first and second input tee junctions for feeding the rf energy to first and second columns of the slots, the first and second columns of slots having, respectively, n1 and n2 numbers of slots with n1>n2. The manifold includes a power divider, and first and second waveguide lengths connected to the power divider for receiving rf energy.

Abstract: A slot antenna is provided which includes first and second oppositely disposed metallic plates with a dielectric layer disposed therebetween. An array of horizontal and vertical radiating elements are formed on the first metallic plate. An array of horizontal coupling slots and an array of vertical coupling slots are formed in the second metallic plate. The antenna further includes first and second beam formers for providing a necessary field of view beam coverage. The array of horizontal coupling slots are operatively coupled to the first beam former and the array of vertical coupling slots are operatively coupled to the second beam former. Accordingly, the slot antenna may operate to transmit and receive linearly polarized energy. The antenna may further include a polarizer disposed above the upper metallic plate for converting between linear and circular polarization so as to allow for antenna operation with single or dual circular polarization energy.

Abstract: A waveguide antenna comprising a waveguide in one wall of which a number of transversal slots are arranged. In connection with the transversal slots, electrically conducting waveguide elements are arranged which are located parallel to the wavelength wall and substantially symmetrically with respect to the transversal slots. In this way new slots are formed at the ends of the waveguide elements.

Abstract: A microwave system for locating a mobile element comprises a hollow tube forming a waveguide fed with microwave signals. A location beacon radiates into free space an electromagnetic wave derived from the microwave signals propagating in the waveguide. A location antenna attached to the mobile element receives the electromagnetic wave radiated by the beacon. The location beacon transmits to the antenna a single electric field signal enabling transmission of a location message.

Abstract: A planar slot antenna grid contains a number of waveguide-slot radiators having wide reverse side and wide outer side faces in which there are obtained, respectively, exciting slots of coupling and radiating slots. The faces lie correspondingly in two parallel planes, and a waveguide-feeder network is formed by waveguide distributors of power and feeding waveguides. Channels of the waveguides communicate with the exciting slots of coupling. The waveguide-slot radiators represent strip-line waveguides including a common dielectric substrate. The reverse side of the substrate is covered by a metallized coating serving as a common wide reverse side face of the waveguide-slot radiators. Each wide outer side face of the radiators represents a strip-line made of alternating narrow and wide segments formed on the outer side face of the dielectric substrate.

Abstract: In a waveguide (1) having slots (2, 3) perpendicular to the axis of the waveguide, cut out in a narrow wall of the waveguide, there are positioned, on each side of each slot, pairs of metal flat plates (21, 22; 31, 32) symmetrical with respect to the central axis of the slot. These flat plates modify the electrical field at the associated slot and make it possible to excite it, the value of the coupling being set by the adjusting of the size of the flat plates and of their position with respect to the corresponding radiating slot.

Abstract: Dielectric strips made of a dielectric material are placed between a pair of conductor plates located a specified distance apart. Cutouts are formed in the dielectric strips. The cutouts, a part of each dielectric strip is formed into an electrically asymmetric portion. When high-frequency power is supplied to the dielectric strips, the power is transmitted through an NRD waveguide composed of the dielectric strips and the pair of conductor plates, with the result that electromagnetic wave is radiated from the cutouts into the space between the conductor plates. This electromagnetic wave excites the radiation elements formed in the conductor plates, which then radiate electromagnetic waves.

Abstract: A nonresonant, traveling-wave V-shaped slot antenna providing high gain and a broad bandwidth for coupling infrared radiation onto a detector. The V-shaped slot antenna includes a relatively thick dielectric substrate and a metallization layer formed on the substrate. The metallization layer includes a pair of slots positioned at an angle .phi..sub.1 to form a V-shaped slot. The slot angle .phi..sub.1 is equal to approximately twice the radiation angle .psi., which is defined as the arccos of v.sub.d /v.sub.s, where v.sub.s is the propagation velocity of the infrared radiation in the two slots and v.sub.d is the propagation velocity of the radiation in the dielectric substrate. At the slot angle .phi..sub.1, the radiation in the two slots adds in phase to produce a single high-gain beam along the V axis.

Abstract: The target seeker system includes two radio frequency antennas consisting of two sets of radio frequency selective annular slot patch excited radiator receiver elements, one set for K-band energy, the other for X-band energy, sharing a common ground plane. The radio frequency antennas have a single multi-band image plate consisting of resonant dichroic surfaces which will selectively reflect X- and K-band energy. An image plate is formed with conductive patterns on each side of a low dielectric material. The reflective pattern acts as a quarter wavelength thick plate at the operating frequency. The top of the image plate which has X-band reflectors is spaced at one-half of the desired X-band wavelength above the ground plane and the K-band reflector on the bottom of the image plate is spaced at one-half of the desired K-band wavelength.

Abstract: An antenna 10 with a dual end resonant slot array feed 26 improves the bandwidth performance of a resonant slotted waveguide planar array antenna 10. The dual end resonant slot array feed 26 includes a tee junction 28/30 which may be either an E-plane 28 or H-plane 30, two waveguide sections 32, 34, and two E-plane waveguide bends 36, 38. The two waveguide sections 32, 34 are formed by a septum 40 mounted in a slotted waveguide 42 for separating the input tee junction 38, 30 from the slots 44 of the slotted waveguide. The ends of the septum 40 coacting with the ends of the waveguide to form the E-plane waveguide beds 36, 38 . Thus, resonant feeding of the series-slot waveguides 50 is achieved by the opposing traveling waves thereby eliminating the need to use resonant short circuits, cavities, or folded short circuits.

Abstract: An antenna scanned by frequency variation, comprising: exciter means for producing a plane electromagnetic wave at a given frequency which is variable about a center frequency; and radiating means receiving the plane wave produced by the exciter means and subjecting the plane wave to a plurality of successive reflections, the radiating means including means for allowing a fraction of the plane wave to leak to the outside after each successive reflection in order to enable it to radiate to the outside; the phase shift of the wave between two reflections varying as a function of the frequency of the wave and the set of radiated waves produced in this manner thus having a determined relative phase difference, which is variable as a function of the frequency of the wave generated by the exciter means and which defines transmission having a main lobe whose direction is itself variable as a function of the said frequency.

Abstract: An array of antenna elements are configured in a lattice-like layer, each element being similarly oriented such that the elements form a two-dimensional antenna aperture that may form a planar or curved surface of a desired shape. The antenna elements are connected in a one-to-one correspondence in both number and form to a lattice of identical, multiport, isotropic, wave-coupling networks physically located under the antenna element array as a backplane of the antenna element layer. Each wave-coupling network or "unit cell" couples signals to and/or from its corresponding antenna element and further functions as a phase delay module in a two-dimensional signal distribution network. This invention can be embodied in a two-dimensional signal distribution network and in a wrap-around, conformal, millimeter-wave, phased array antenna, such as on the nose of a missile.

Abstract: An active phased array is provided that includes a plurality of subarrays (20) having an upper RF radiating panel assembly (22) including a plurality of radiating waveguides (26) and a feed waveguide (24) all formed of aluminum. RF radiating slots (28) are cut into one wall of each of the radiating waveguides and a silver-quartz mirror (42), with corresponding slots (44), is bonded to the outside surface. The array further includes a non-RF radiating lower aluminum support panel assembly (34) with a silver-quartz mirror (46) bonded to the outside face. The mirrors efficiently radiate thermal energy in the presence of sunlight. An active electronics module (30) is mounted in an aluminum housing, and includes an RF probe (56). The module 30 is supplied with RF signals, control signals and DC bias voltage over transmission lines contained in a multilayered circuit board (32). RF energy emitted by the probe is coupled from the feed waveguide to the radiating waveguides.

Abstract: A variable width waveguide scanner includes a pair of spaced apart waveguides defined by U-shaped sleeves each having an open end. A U-shaped plunger having spaced apart parallel first and second arms is coupled to the waveguides such that the arms are received by the open ends of the sleeves and are reciprocatingly slidable in the sleeves. A plurality of radiating elements in the form of spaced apart slots are formed in an end wall of each waveguide.

Abstract: A shunt coupled array of slots in a waveguide broadwall, wherein the slots are defined by a punch operation which leaves a tab connected at one side of the slot. The slot side to which the tabs are connected is alternated. The tabs extend downwardly into the waveguide and provide a means for exciting the slots without requiring the longitudinal slots to be alternatively offset. Thus, the invention provides a method of fabrication which permits elimination of the slot offsets, while at the same time is lower in cost than conventional methods of creating slot openings arrays. Higher antenna gain results from a given aperture when slot offsets are eliminated and the slots are truly located along straight lines in rows and columns.

Abstract: An elliptically polarized antenna is disclosed which includes a conductive mast having at least one elongated slot extending longitudinally of the mast at the outer periphery thereof and wherein energy is fed to the slot for exciting horizontally polarized waves. A pair of conductive elements are associated with each slot for exciting vertically polarized waves. This includes first and second elements each having a connecting end portion extending transversely from and connected to the mast near the midpoint of one elongated side of the slot with the element having a pair of free end portions extending in substantially opposing directions parallel to the slot. The free end portions have their respective lengths chosen relative to each other for purposes of controlling the split of the radiated energy between the horizontally and vertically polarized waves.