Abstract: A microwave antenna comprises an antenna array comprising a plurality of antenna elements. An antenna element comprises a cover, a hollow waveguide formed within the cover for guiding microwave radiation at an operating frequency between a first open end portion and a second end portion arranged opposite the first end portion, a septum arranged centrally and along the longitudinal direction within the waveguide and separating said waveguide into two waveguide portions, a substrate arrangement arranged at the second end portion within the cover, said substrate arrangement comprising a ground plane and line structures arranged on both sides of and at a distance from said ground plane and a substrate integrated waveguide, a waveguide transition arranged between said hollow waveguide and said substrate integrated waveguide, an integrated circuit arranged within said cover and electrically contacted to said ground plane and said line structures, and terminals electrically contacted to said integrated circuit.

Abstract: An antenna element and a phased array antenna including a plurality of such antenna elements are described. The antenna element includes a waveguide configured for operating in a below-cutoff mode and having a cavity, an exciter configured for exciting the waveguide, and a shield. The shield includes a holder arranged within the cavity, and a front plate mounted on the holder and disposed over at least a part of the exciter.

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: An aperture of an antenna for a radar system comprises a first waveguide comprising a first protrusion and a second protrusion, each protrusion extending longitudinally along one side of the first waveguide. The aperture further comprises a second waveguide comprising a third protrusion and a fourth protrusion, each protrusion extending longitudinally along one side of the second waveguide. The first and third protrusions and second and fourth protrusions adjoin to form a radio frequency choke at least partially suppressing cross polarization of radio frequencies between the first and second waveguides.

Abstract: A method and apparatus comprising a dielectric structure and a plurality of conductive segments. The dielectric structure is configured for placement in a waveguide. The plurality of conductive segments is located within the dielectric structure. Each of the plurality of conductive segments is configured to reduce a passing of a number of frequencies of electromagnetic signals traveling through the dielectric structure.

Abstract: A dielectric antenna includes at least one dielectric unit. Each dielectric unit is separated into a first region and a second region, and the second region could have a bending portion. A conductor covers a surface of the second region of the dielectric unit to form a waveguide structure. The waveguide structure has a first endpoint connected to the first region and a second endpoint serving as a signal feeding terminal for feeding or receiving signals.

Abstract: An antenna for broadband satellite communication including an array of primary horn antenna elements which are connected to one another by a waveguide feed network.

Abstract: An apparatus for an antenna system comprising one or more blades for splitting the electromagnetic field received by an antenna into a plurality of sections corresponding to separate beams and redirecting said plurality of sections for detection by a plurality of detectors. The apparatus may comprise a plurality of blades for splitting the field into successively smaller and smaller portions. The plurality of detectors can be positioned outside the focal region of the antenna system. The apparatus may further comprise focusing means for focusing the sections of the field onto another blade or a detector. There is also provided an antenna system comprising a plurality of feed horns for producing a plurality of beams; and a plurality of elements for redirecting said beams towards a focal region of the antenna system so as to form a group of closely packed beams for transmission by the antenna system.

Abstract: Provided is an antenna apparatus which employs a small number of antenna devices and is intended to obtain a desired pattern without adjusting amplitude level and phase of each antenna device. The antenna apparatus includes a first ridge horn antenna, and a second ridge horn antenna spaced apart from the first ridge horn antenna by a determined distance. Here, a multi-beam pattern is generated using a third-order mode beam pattern of a synthetic beam obtained by synthesizing beams respectively radiated from the first and second ridge horn antennas. Accordingly, the antenna apparatus can be simplified, and a desired multi-beam pattern can be obtained without adjusting signal level and phase of each antenna device. Also, by employing the ridge horn antennas as array devices, the antenna apparatus can be used in a wide frequency band.

Abstract: A panel array antenna has a waveguide network coupling an input feed to a plurality of primary coupling cavities. Each of the primary coupling cavities is provided with four output ports, each of the output ports coupled to a horn radiator. The waveguide network is provided on a second side of an input layer and a first side of a first intermediate layer. The primary coupling cavities are provided on a second side of the first intermediate layer and the output ports provided on a first side of an output layer, each of the output ports in communication with one of the horn radiators. The horn radiators are provided as an array of horn radiators on a second side of the output layer. Additional layers, such as a second intermediate layer and/or slot layer, may also be applied, for example to further simplify the waveguide network and/or rotate the polarization.

Abstract: A modular feed network is provided with a segment base provided with a feed aperture, a corner cavity at each corner and a tap cavity at a mid-section of each of two opposite sides. A segment top is provided with a plurality of output ports. The segment top is dimensioned to seat upon the segment base to form a segment pair. the segment base provided with a plurality of waveguides between cavities of the segment base. The modular feed network is configurable via a range of feed, bypass and/or power divider taps seated in the apertures and/or cavities to form a waveguide network of varied numbers of output ports by routing across one or more of the segment tops. For example, the modular feed network may comprise 1, 4 or 16 of the segment bases retained side to side.

Abstract: Methods and systems for a smart antenna utilizing leaky wave antennas (LWAs) are disclosed and may include a programmable polarization antenna including one or more pairs of LWAs configured along different axes. One or more pairs of leaky wave antennas may be configured to adjust polarization and/or polarity of one or more RF signals communicated by the programmable polarization antenna. RF signals may be communicated via the configured programmable polarization antenna utilizing the configured one or more pairs of the leaky wave antennas. A resonant frequency of the LWAs may be configured utilizing micro-electro-mechanical systems (MEMS) deflection. The polarization and/or polarity may be configured utilizing switched phase modules. The LWAs may include microstrip or coplanar waveguides, wherein a cavity height of the LWAs is dependent on spacing between conductive lines in the waveguides. The LWAs may be integrated in one or more integrated circuits, packages, and/or printed circuit boards.

Abstract: A communications system including an antenna array and electronics assembly that may be mounted on and in a vehicle. The communication system may generally comprise an external subassembly that is mounted on an exterior surface of the vehicle, and an internal subassembly that is located within the vehicle, the external and internal subassemblies being communicatively coupled to one another. The external subassembly may comprise the antenna array as well as mounting equipment and steering actuators to move the antenna array in azimuth, elevation and polarization (for example, to track a satellite or other signal source). The internal subassembly may comprise most of the electronics associated with the communication system.

Abstract: A multiple feed antenna includes a first waveguide having a first upper aperture with a first wall surrounding the first upper aperture; a second waveguide disposed in parallel to the first waveguide, in which the second waveguide has a second upper aperture; a second wall surrounding the first wall, with a first groove between the second wall and the first wall; a third wall surrounding the second wall and the second upper aperture, with a second groove between the third wall and the second wall; a fourth wall surrounding the third wall, with a third groove between the fourth wall and the third wall; and a plurality of ribs connecting the first wall and the second wall.

Abstract: An antenna device includes antennas, each of which includes antenna elements arranged in a longitudinal direction, arranged side by side in a transverse direction intersecting the longitudinal direction, wherein an interval between the antennas arranged side by side in the transverse direction is approximately 2?. where ? is a free space wavelength corresponding to an operating frequency, and each of the antenna elements includes a horn formed therein.

Abstract: Described are a notch antenna and an array antenna based on a low profile stripline feed. The notch antenna includes a planar dielectric substrate having upper and lower surfaces. Each surface has a conductive layer with an opening therein. A notch antenna element is disposed on the conductive layer of the upper surface at the opening. A stripline embedded in the planar dielectric substrate extends under the notch antenna element. The stripline is adapted to couple an RF signal between the stripline and the notch antenna element. A conductive via is electrically coupled to the stripline and extends from the stripline to the opening in the conductive layer on the lower surface so that the RF signal is accessible at the lower surface.

Abstract: An antenna (100,200,300, 400, 500) comprising first (110, 210, 310, 410, 430) and second (120, 220, 320, 420, 440) structures for guiding electromagnetic waves, each comprising groups (111, 130, 150, 230, 330; 140,160, 240, 340, 445, 470) of radiation elements. For adjacent sections in 5 the structures, at least one applies: ?Groups of radiation elements are distributed along the two structures such that a group (110, 130, 150) in the first structure overlaps a group (120, 140,160) in the second structure partially or not at all. ?Radiation elements within said groups (230; 240) exhibit a common 10 main direction of extension within the group, and differs between the first and the second groups by an angle of at least 10 degrees. ?The radiation elements of the groups (330, 340) are distributed along the structures (310, 320) on sides of the structures which face different directions.

Abstract: An antenna element and a phased array antenna including a plurality of such antenna elements are described. The antenna element includes a waveguide configured for operating in a below-cutoff mode and having a cavity, an exciter configured for exciting the waveguide, and a shield. The shield includes a holder arranged within the cavity, and a front plate mounted on the holder and disposed over at least a part of the exciter.

Abstract: An antenna feed device (100) having a first waveguide (102) and a second waveguide (104) separated from the first waveguide (102), each of which is assigned to feed one polarization of a dedicated antenna and each of said waveguides exhibit an overall L-shape form where at least one section of the L-shape of each waveguide is in parallel to the other, both having respectively a first (106) and a second (108) antenna end ending in one plane for connection to an ortho-mode transducer associated with the antenna, while the other sections of the two L-shape waveguides extend in opposite directions, having respectively a first (110) and a second (112) radio end, each of which ends with a single waveguide port for connection to a radio equipment and the waveguides arrangement yields an overall compact T-shape interconnection of the antenna and the radios dedicated to the orthogonal polarizations.

Abstract: A mode filter for an antenna having at least one element aperture is provided. The mode filter includes at least one waveguide extension to extend the at least one element aperture, and at least one two-by-two (2×2) array of quad-ridged waveguide sections connected to a respective at least one waveguide extension. When the at least one waveguide extension is positioned between the at least one element aperture and the at least one two-by-two (2×2) array of quad-ridged waveguide sections, undesired electromagnetic modes of the antenna are suppressed.

Abstract: A leaky-wave antenna capable of multi-plane scanning is provided. The leaky-wave antenna includes a substrate, a first antenna series, a second antenna series and a plurality of control units. The first antenna series intersects with the second antenna series to share a predetermined antenna unit among many antenna units. A part of the antenna units is connected in series to extend from a first and a second transmission lines of the predetermined antenna unit to compose the first antenna series, and the other antenna units are connected in series to extend from a third and a fourth transmission lines of the predetermined antenna unit to compose the second antenna series. The control units control the transmission paths between the first to the fourth transmission lines and the antenna units, and switch a leaky beam to different scanning planes, wherein the leaky beam scans with frequency variation through the antenna units.

Abstract: The invention relates to an antenna comprising a transmission surface, an array of elementary antennas each extending from the transmission surface, first and second superimposed electromagnetic waveguides. The first waveguide is adapted to power the second waveguide from a collection inlet, and the second waveguide is adapted to power the elementary antennas. The antenna comprises means for coupling the electromagnetic energy associated with the electromagnetic wave between the first and second waveguides. The coupling means separate the transmission surface into two concentric regions made up of a peripheral region and an internal region situated at the collection inlet, each comprising at least one elementary antenna.

Abstract: Apparatus and methods for packaging IC chips and laminated antenna structures with laminated waveguide structures that are integrally constructed as part of an antenna package to form compact integrated radio/wireless communications systems for millimeter wave applications.

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: The present invention relates to a system of multi-beam antennas comprising M radiating sources and P networks of N radiating elements, P being greater than 1 and N being an even whole number, the network elements being connected two by two via transmission lines of the same electrical length. In addition, the P networks are co-located at the centre of each network, the M radiating sources are each positioned at a distance Li from said centre, the distance Li being strictly less than the distance of the field called the far field and i varying from 1 to M. This system can be used with MIMO type devices.

Abstract: Structure and method for an aperture plate for use in a phased array antenna is disclosed. The aperture plate includes a plurality of waveguide transitions, each with a radiating end, a coupling end and a body portion extending from the radiating end to the coupling end. The waveguide transitions are spaced apart from each other wherein at least a pair of waveguide transitions are spaced apart closer to each other at the radiating end than at the coupling end. The method of manufacturing an aperture plate for a phased array antenna includes sizing a plurality of waveguide transitions based upon certain operating requirements, determining a radiating lattice spacing and configuration based upon the operating requirements, determining a coupling lattice spacing and configuration based upon antenna electronics packaging, optimizing an aperture plate thickness to achieve the radiating lattice and the coupling lattice spacing and configuration, and forming the aperture plate.

Abstract: A motion sensing method and apparatus includes a housing enclosing a microwave motion sensor including an antenna, and a security system. The antenna may be a patch antenna which includes microwave radiating elements for transmitting and receiving a microwave signal for sensing motion. A reflector is attached to the housing and positioned above the antenna for downward shaping of the microwave signal. The microwave radiating elements together with the reflector provide a radiation pattern where a main beam is transmitted in a direction orthogonal to a surface of the antenna and a sided lobe is transmitted downward in amplitude below the microwave motion sensor. An alarm circuit indicates when the microwave sensor detects motion in armed mode, and a masking circuit indicates when the microwave sensor detects motion in a mask zone when the security system is unarmed. A second sensor may be positioned beneath the microwave motion sensor.

Abstract: A plurality of three-dimensional radiator elements, each radiator element transmitting or receiving electromagnetic waves by a radiating top side. The radiator elements are arranged so that their radiating top sides are substantially parallel and so that at least one pair of adjacent radiator elements are separated by a dielectric gap between sidewalls, the gap behaving like a waveguide which couples electromagnetic interferences with the electromagnetic waves. The adjacent radiator elements further comprise a structure to suppress the coupling effect without establishing a galvanic contact with its adjacent radiator element.

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: An aperture of an antenna for a radar system comprises a first waveguide comprising a first protrusion and a second protrusion, each protrusion extending longitudinally along one side of the first waveguide. The aperture further comprises a second waveguide comprising a third protrusion and a fourth protrusion, each protrusion extending longitudinally along one side of the second waveguide. The first and third protrusions and second and fourth protrusions adjoin to form a radio frequency choke at least partially suppressing cross polarization of radio frequencies between the first and second waveguides.

Abstract: A feed for an antenna configured for use with a radar system or a satellite communication system is configured to operate in multiple bands. The feed comprises a plurality of concentric waveguides. The feed further comprises a first pair of diametrically opposed probes forming a first axis and electrically coupled to at least one of the plurality of concentric waveguides. The feed further comprises a second pair of diametrically opposed probes forming a second axis and electrically coupled to the at least one of the plurality of concentric waveguides. The first and second axis are orthogonal and the first and second pairs of diametrically opposed probes are configured to generate a sum beam and difference beam in the at least one of the plurality of concentric waveguides.

Abstract: An apparatus comprises a structure, an array of oscillator units, a plurality of waveguides in the structure, and a synchronizing cavity located within the structure. The array of oscillator units has a plurality of rows and a plurality of columns associated with the structure. Oscillator units in a row within the array of oscillator units are directly coupled to each other. The plurality of waveguides is configured to couple the array of oscillator units to the synchronizing cavity. The synchronizing cavity is configured to cause the array of oscillator units to operate at substantially a common frequency.

Abstract: A waveguide includes a dielectric substrate having first and second opposed surfaces defining a longitudinal wave propagation path therebetween; and a conductive grid on the first surface of the substrate and comprising a plurality of substantially parallel metal strips, each defining an axis. The grid renders the first surface of the substrate opaque to a longitudinal electromagnetic wave propagating along the longitudinal wave propagation path and polarized in a direction substantially parallel to the axes of the strips. The grid allows the first surface of the substrate to be transparent to a transverse electromagnetic wave having a transverse propagation path that intersects the first and second surfaces of the substrate and having a polarization in a direction substantially normal to the plurality of metal strips. A diffraction grating on the second surface allows the waveguide to function as an antenna element that may be employed in a beam-steering antenna system.

Abstract: An antenna for broadband satellite communication including an array of primary horn antenna elements which are connected to one another by a waveguide feed network.

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: Wideband radiating elements, methods of transmitting and receiving signals using a wideband radiating element, standalone antennas, and array antennas are disclosed. The wideband radiating element (antenna) has wide bandwidth for a relatively constant beamwidth and comprises a section of waveguide, a patch radiator, and one or more tuned loops. The wideband radiating element may comprise: a section of waveguide, at least one dipole antenna element, and at least one tuned circuit. Each dipole antenna element is disposed within the waveguide section as a feed for the waveguide section.

Abstract: A control device includes a first communication interface for communicating first control data with a first plurality of communication devices that utilize the millimeter wave frequency band in accordance with a first protocol, wherein the first communication interface utilizes the millimeter wave frequency band in accordance with the first protocol. A second communication interface communicates second control data with a second plurality of communication devices that utilize the millimeter wave frequency band in accordance with a second protocol, wherein the second communication interface utilizes the millimeter wave frequency band in accordance with the second protocol. A resource controller allocates resources of the millimeter wave frequency band to the first plurality of communication devices and the second plurality of communication devices based on the first control data and the second control data.

Abstract: This high-frequency waveguide is formed by first and second conductors (22, 23) disposed opposite each other at a spacing of ?0/2, where ?0 is the free space wavelength of the operating frequency of a high-frequency signal. A ridge (25) is provided at the waveguide formation portion between these first and second conductors (22, 23), which protrudes from one of the first and second conductors (22, 23) toward the other and is formed extending along the waveguide formation portion. A plurality of columnar protrusions (24) with a height of ?0/4 are disposed at a spacing of less than ?0/2 to at least one of the first and second conductors (22, 23) on the outside of the waveguide formation portion and to the outside of the ridge (25).

Abstract: Methods, systems, and apparatuses for receiving signals from communications satellites are disclosed.

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 method and apparatus comprising a dielectric structure and a plurality of conductive segments. The dielectric structure is configured for placement in a waveguide. The plurality of conductive segments is located within the dielectric structure. Each of the plurality of conductive segments is configured to reduce a passing of a number of frequencies of electromagnetic signals traveling through the dielectric structure.

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: In a waveguide structure (8), a movable waveguide component (10) and an immovable waveguide component (12) are opposed at a predetermined interval. Further, at least either the movable waveguide component (10) or the immovable waveguide component (12) includes grooves (13, 29) opened towards the waveguide component opposed thereto (10, 12). Protrusions (44) are formed outside of at least one of the grooves (13, 29). The protrusions (44) respectively have a height of roughly ?/4 (where ? is a wavelength of radio waves to be used).

Abstract: A phased array antenna system may include a sheet of conductive material with a plurality of aperture antenna elements formed in the sheet of conductive material. Each of the plurality of aperture antenna elements is capable of sending and receiving electromagnetic energy. The phased array antenna system may also include a wide angle impedance match (WAIM) layer of material disposed over the plurality of aperture antenna elements formed in the sheet of conductive material. The WAIM layer of material includes a plurality of metamaterial particles. The plurality of metamaterial particles are selected and arranged to minimize return loss and to optimize an impedance match between the phased array antenna system and free space to permit scanning of the phased array antenna system up to a predetermined angle in elevation.

Abstract: A low-cost, compact circular waveguide array antenna which improves an antenna reflection loss characteristic and enables an improvement in radiation characteristics, particularly radiation gain. The circular waveguide array antenna includes feeding portions which feed electromagnetic waves to one ends of circular waveguides and radiation apertures which radiate the electromagnetic waves at the opposite ends. Each circular waveguide includes a conical horn, with a diameter of a feeding side aperture at the feeding portion end being a, a diameter of the radiation aperture being d, which is larger than the diameter a of the feeding side aperture, and an opening angle being 2?. If a wavelength of a central frequency of an employed frequency band is ?, then a value of ?, which is half of the opening angle 2?, is set between 0.8×Arcsin(0.1349114/(d/?)) and 1.2×Arcsin(0.1349114/(d/?)).

Abstract: A method and apparatus for stacked waveguide horns using dual polarity feeds oriented in quadrature have been disclosed.

Abstract: Methods and systems for wireless communication utilizing leaky wave antennas (LWAs) on a printed circuit board are disclosed and may include communicating RF signals via LWAs in an integrated circuit (chip) and/or package in a wireless device to LWAs in a printed circuit board in the wireless device. RF signals may then be communicated via the LWAs in the printed circuit board to external devices, and may communicated vertically or at a desired angle from the surface. The RF signals may be communicated between regions within the printed circuit board. The LWAs may include microstrip or coplanar waveguides where a cavity height of the LWAs may be configured by controlling spacing between conductive lines in the waveguides. The chip may be flip-chip-bonded to an package which may be affixed to a printed circuit board. A pair of the plurality of LWAs may be stacked to communicate signals in opposite directions.

Abstract: Methods and systems for converting RF power to DC power utilizing a leaky wave antenna (LWA) are disclosed and may include receiving RF wireless signals utilizing one or more LWAs in a wireless device, and generating one or more DC voltages from the received RF signals utilizing cascaded rectifier cells. A resonant frequency of the LWAs may be configured utilizing micro-electro-mechanical systems (MEMS) deflection. The LWAs may be configured to receive the RF signals from a desired direction. The LWAs may comprise microstrip or coplanar waveguides, wherein a cavity height of the LWAs is dependent on a spacing between conductive lines in the waveguides. The LWAs may be integrated in one or more integrated circuits, integrated circuit packages, and/or printed circuit boards. The packages may be affixed to one or more printed circuit boards and the integrated circuits may be flip-chip-bonded to the packages.

Abstract: Methods and systems for a duplexing leaky wave antenna (LWA) are disclosed. In this regard, RF signals may be concurrently transmitted and received via a leaky wave antenna, wherein a height of a first portion of a resonant cavity of the leaky wave antenna is different than a height of a second portion of the resonant cavity. RF signals transmitted may be at or near a first frequency and RF signals received be at or near a second frequency. The height of the first portion of the resonant cavity and/or the height of the second portion of the resonant cavity may be controlled by applying one or more voltages which causes one or both reflective surface of the leaky wave antenna to deflect. The leaky wave antenna may be integrated on and/or within an integrated circuit, an integrated circuit package, a printed circuit board, or a combination thereof.

Abstract: An integrated antenna and reflector feed is provided which is structured as a waveguide cavity antenna or array having a curved reflector coupled to a sidewall of the waveguide cavity. A radiation source is situated facing the curved reflector and one or more radiating elements are provided on a top surface of the waveguide cavity. Several curved reflector feeds may be used, operating in the same or different frequencies.