Abstract: The invention provides a hydrodynamically and stealth shaped suite of antas and sensors mounted above a hydrodynamically and stealth shaped mast. The mast is configured to extend from the sail of a submerged vessel to the surface so as to provide the vessel with satellite communications capabilities. The hydrodynamic shape of the mast minimizes the surface wake and the stealth shape of the antenna suite and mast minimizes the radar cross section of the system, lessening detection by hostile forces. To obtain a stealth shape, the radar suite utilizes a conformal phased array antenna. In addition, electro-optical sensors in the antenna suite provide visual, environmental and other sensing capabilities to the system. Further, structurally embedded ESM antennas provide ESM and radar capabilities.

Abstract: A common aperture, dual mode semi-active laser (SAL) and millimeter wave (MMW) sensor having transreflector configured to allow transmission of SAL energy therethrough, a separator and a fresnel lens configured to pass MMW energy therethrough and to focus SAL energy passing therethrough, the separator being configured to separate SAL energy from MMW energy, and a twist reflector positioned in alignment with the transreflector, configured to rotate the polarization of the MMW energy such that, for received MMW energy, the twist reflector reflects and rotates the received MMW energy toward the transreflector, which reflects it onto a feed and comparator, and for transmitted MMW energy, the transreflector reflects toward the twist reflector, whereupon polarization of the transmitted MMW energy is rotated and reflected therefrom to then pass through the transreflector.

Abstract: A fixed dual frequency band antenna for a dual frequency band radio transceiver where the two frequency bands are not harmonically related. The antenna includes a straight radiating antenna portion terminated by a helical wire radiating antenna portion, with the total electrical length of the antenna being approximately three quarters of the wavelength at the center frequency of the higher of the two frequency bands. A conductive radiating cap terminates the helical portion and a conductive antenna base is connected to the straight portion at the end opposite the helical portion. A matching circuit coupled between the base and the transceiver circuitry is arranged to substantially cancel the reactive portion of the impedance of the antenna for both frequency bands and to substantially equalize the resistive portion of the impedance of the antenna to the resistive portion of the output impedance of the radio transceiver.

Abstract: A vehicle antenna arrangement and an auxiliary vehicle antenna are proposed that enable a further antenna system (55) to be adapted to a vehicle antenna (2). The further antenna system (55) is accommodated in a housing (50) that is mounted on a retaining plate (35). The retaining plate (35) has a recess (40) and is mounted on a vehicle body (1). In the region of the recess (40), the vehicle body (1) has an aperture (20), through which a tube (15) is passed that is connected to a base plate (10) and an antenna base (5), mounted on it, of the vehicle antenna (2). The base plate (10) rests on the retaining plate (35) via protrusions (80). Two antenna cables (25) and (26) are extended to the antenna base (5) through the tube (15). A further antenna cable (45) leaves the tube (15) through a lateral opening (30) between the vehicle body (1) and the base plate (10), the spacing (90) between the vehicle body (1) and the base plate (10) being greater than the diameter of the further antenna cable (45).

Abstract: A novel RF antenna and method of manufacture thereof is disclosed. With this novel antenna the energy radiates in all directions including both left hand and right hand polarizations. In one embodiment of the invention, the antenna consists of two equal size rectangularly shaped conductive sheets positioned in parallel with each other. The side dimensions are nearly a half wavelength of the center frequency. The rectangle is nearly a square with one dimension slightly larger than the other. The feed point is at any of the corners. The difference in side dimensions cause the antenna to resonate at two adjacent frequencies, one slightly above the working frequency and the other slightly below. This creates a phase difference between the orthogonal modes of operation at the working frequency. A 90 degree phase difference generates circular polarization.

Abstract: A dual band, dual polarized antenna comprising an array of resonators in a plane for radiating at a first frequency, a ring resonator in a plane, the array of resonators being contained within a projection of the boundary of the ring resonator, the ring resonator for radiating at a second frequency which is lower than the first frequency, apparatus for exciting the array of resonators to cause them to radiate at the first frequency with dual polarizations simultaneously, and apparatus for exciting the ring resonator to cause it to radiate at the second frequency with dual polarizations simultaneously.

Abstract: An antenna device includes a first antenna capable of moving between a storage position where the first antenna is contained within an equipment housing and an extended position where the first antenna is pulled out of the device housing for receiving and/or transmitting a signal. A second antenna is attached to the tip of the first antenna for receiving and/or transmitting a signal when the first antenna assumes the storage position. The rotator rotates the first antenna with respect to the device housing in the extended position.

Abstract: An improved loop antenna (10) comprises first (12) and second (16) conductive loops. Each of the first and second conductive loops has a discontinuity (14, 18). The first and second conductive loops (12, 16) are arranged substantially concentrically to form a capacitive coupling such that the tuned frequency of the loop antenna (10) has improved protection from external capacitance effects.

Abstract: A combined satellite and terrestrial antenna has a reflector dish formed of a conductive metal supported by but electrically insulated from a support structure. A pick-up for the satellite transmission signal is also supported by the support structure at a position to receive satellite microwave signals reflected from the dish. An electrical connector is attached to and in electrical contact with the metal of the dish and a transmission line extends from the connector to transmit UHF/VHF signals which are received by the metal dish itself. The UHF/VHF signals may be combined with the signals from the satellite pick-up and transmitted together on a common transmission line leading to a receiver. A loop section may be connected by swivel connectors to the periphery of the reflector dish to be in electrical contact therewith to further enhance the reception of UHF/VHF frequencies. The loop section may be adjusted to a position either in the front or the back of the dish to maximize reception of UHF/VHF signals.

Abstract: A combination satellite television signal receiving antenna and a UHF/VHF antenna, particularly suitable for use with recreational vehicles. The satellite antenna is mounted for both horizontal and vertical adjustment having a circular periphery and the UHF/VHF dipole antenna is attached thereto and is of an arcuate configuration defining a portion of a circle concentric to the satellite receiving antenna dish configuration. The television and UHF/VHF antenna are mounted for simultaneous adjustment.

Abstract: A dual-band feed for use in a microwave reflector antenna. The feed for one band is a an open-ended waveguide or a horn-type feed and the feed for the second band is a helix antenna. The wave-guide or horn-type antenna is located inside of the helix antenna and concentric with the helix antenna so as to cause the beams from the two feeds that are reflected by the reflector to be directed in the same direction.

Abstract: A single planar antenna for use in two frequency bands includes radiating portions for the two bands joined by a connecting portion and spaced from a ground plane. Each radiating portion is formed as a planar inverted F-antenna. A grounding pin interconnects the connecting portion and the ground plane and a single feed pin connects the connecting portion to the input/output port of transceiver circuitry.

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 90 degree azimuth beamwidth is achieved in a narrow cellular antenna, by inclusion of sidewalls. To improve front-to-back performance, slot radiating elements extending through the sidewalls re-radiate signals behind the antenna. Signals re-radiated from the slot elements are effective to partially cancel signals otherwise radiated behind the antenna as a result of diffraction. H-shaped slots are described for sidewall use and side-to-side slots are described for endwall use. Slots may be dielectrically loaded by contiguous portions of a radome.

Abstract: An antenna structure includes a plurality of vertical directed antennas mounted on an insulated cylindrical substrate. A parabolic reflecting antenna is mounted at one end of the cylindrical substrate cavity and a dielectric lens admits radiation through the cylindrical cavity to the parabolic reflector. Optical detectors are located on the cylindrical substrate periphery and exposed to optical signals through an InfraRed (IR) optical filter.

Abstract: A communication and tracking antenna is formed by embedding a tracking patch array in a shaped dual gridded reflector. The reflector includes first and second reflector grids that have orthogonally arranged grid lines and are respectively fed by feed horns. The patch array is positioned so that the first reflector grid is between the patch array and the first feed horn. The first reflector grid thus serves as a filter to remove unwanted polarization components and enhance the quality of both the tracking radiation and the radiation that is reflected from the second reflector grid. In other embodiments, a tracking array is positioned adjacent a reflector's perimeter.

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: An antenna unit and a receiver having such an antenna are disclosed. The antenna includes an antenna body; a first antenna provided on the antenna body for receiving signals transmitted from satellites; at least one second antenna provided on the antenna body for receiving signals transmitted over the earth; a mixer provided in the antenna body for mixing or combining the signals received by the first and second antennas to output the mixed signals as a single output. Further, the receiver includes, in addition to these elements of the antenna unit, a signal separating device for separating the mixed signals into the signal received by the first antenna and the signal received by the second antenna, respectively and then outputting them; and a single cable which connects the mixer and the single separating device to supply the mixed signals thereto.

Abstract: A portable radio device antenna apparatus has a retractable antenna element mounted on the casing of a radio device. The antenna element includes a straight element having an electrical length of .lambda./2 and a helical coil having an electrical length of .lambda./4 and attached to the upper end of the straight element. The casing contains an impedance matching circuit having a pair of terminals and serving to perform impedance matching of the straight element. When the straight element is pulled out from the casing, a feeding metal piece connected to a radio circuit and a lower connection metal piece connected to one terminal of the impedance matching circuit are simultaneously connected to the short-circuit metal fixture of the antenna element, and an upper connection metal piece connected to the other terminal of the impedance matching circuit is brought into contact with the straight element.

Abstract: A low frequency, complementary bowtie antenna structure, including a resistive film, a sheet of silicon impregnated with ferrite material and a sheet of rigid dielectric foam. The film has a linearly tapered resistive coating applied to a surface, and is cut in the shape of a complementary bowtie radiator. A center conductor of a feed coaxial line is soldered to the most conductive section of the resistive material. The outer conductor of the coaxial line is connected to a ground plane. The antenna structure can be used in a conformal, L-band array of bowtie radiators which can be integrated into an X-band array aperture with minimal impact on the radiation and RCS performance of the X-band array.

Abstract: Improved antennas and antenna systems for use in cellular and other wireless communications systems. A folded mono-bow antenna element is provided which has a substantially omnidirectional radiation pattern in a horizontal plane and shows variation in gain in an elevation plane depending upon the size of an associated ground plane. The folded mono-bow antenna element comprises a main bowtie radiating element and parasitic element wherein the main bowtie radiating element and parasitic element are separated by a dielectric material having a dielectric constant preferably less than 4.5 and, in some cases, less than or equal to 3.3. Various antenna arrays and methods of making the same are also provided.

Abstract: A fixed body wide field-of-view conformal antenna array suitable for broadband precision direction finding on missile platforms. The array is configured as multiple sub-arrays of spiral antennas that cover particular regions within the desired field-of-view of the entire array. A lower cost, more reliable and more accurate direction finding solution for missile needs is provided, primarily by the elimination of conventional radomes and antenna gimbal structures. The array can be configured to include multi-mode sensors.

Abstract: A diversity antenna for radio communications including a pair of conductive thin-film patterns used for a first antenna and another pair of conductive thin-film patterns used for a second antenna, the thin-film patterns being installed on a printed circuit board along the direction of the length of the circuit board; a first choke coil which is used to stop a leakage current from the first antenna and cause attenuation of a coupling current from the second antenna, the first choke coil being installed at a location where the leakage current distribution of the first antenna reaches the maximum in a feeder cable connected to the first antenna; and a second choke coil which is used to stop the leakage current from the second antenna, the second choke coil being installed at a location where the leakage current distribution of the second antenna reaches the maximum in a feeder cable for the second antenna.

Abstract: A slot antenna includes a plate-like conductor provided vertically on the upper surface of the metallic cabinet and having a recess, whose length is equal to the half wavelength relative to a using frequency and whose depth is sufficiently smaller than the wavelength. Such a slot antenna is supplied with power to excite a half-wavelength conductor provided in the neighborhood thereof in a non-contact state through a electrostatic capacitive coupling.

Abstract: An energy diversity antenna (100) includes a first antenna (103) and second antenna (113) positioned on a substrate (101). The first antenna is preferably a loop used for receiving radio frequency signals with H-field energy while the second antenna is preferably a monopole used for receiving radio frequency signals with E-field energy. The energy diversity antenna (100) is applicable for use in portable communications devices capable of diversity reception. It is particularly useful in geographic locations where reflections and multipath interference is a problem.

Abstract: A vehicle windowpane antenna comprises a first windowpane antenna element and a second windowpane antenna element which cooperate to perform diversity receiving of a VHF band signal and a UHF band signal.

Abstract: An antenna device for a piece of equipment for transmitting and/or receiving radio signals, wherein the antenna device comprises a first extendable antenna (2), which is movable between an extended position, where it is coupled to the circuitry of the piece of equipment and a retracted position where it is not coupled to the circuitry, the extendable antenna (2) on its lower portion having first holding device (10) cooperating with a second holding device (9) arranged on a guide (5) for the first antenna such that the first antenna is releasably locked in the extended position. According to the invention the first antenna (2) is releasably locked by the first and second holding devices comprising mutually magnetically attractive elements (9,10).

Abstract: The flat-topped antenna apparatus includes a GPS antenna, a mobile radio antenna, a common housing for the antennas mounted over a ground plane and coaxial cables (12,13,13a) acting as electrical supply lines for the antennas. The mobile radio antenna includes a metal sheet (6,6',6a) plane parallel to the ground plane and spaced at a distance (A,A') of 0.04 of an average operating wavelength of a mobile radio frequency band from the ground plane. The metal sheet is electrically connected at an input terminal (11) with an inner conductor (10) of one coaxial cable (13,13a) and also with the ground plane via a short circuit element (7,7a). The GPS antenna is above and rests on the mobile radio antenna and includes a dielectric plate (1,1a) provided with a metal layer (3) connected at an input terminal (4) with an inner conductor (10) of another (12) of the coaxial cables.

Abstract: An improved antenna device for small size portable communication equipment comprising circuits (23) for transmitting and/or receiving radio signals as well as a chassis (25) and a feeding point (22) providing the electrical coupling of the antenna device to the communication equipment. The antenna device comprises a hollow helical antenna (6) fixed externally on the chassis and an antenna rod slidable through the helical antenna and being part of a straight radiator (1). The helical antenna (6) is of quarter-wave type and is coupled constantly via the feeding point (22) to the circuits (23).

Abstract: The invention relates to a device at antenna systems for generating radio waves, including a supporting structure mounting at least one main radiator (3) for transmitting radio waves and where high frequency electric currents are generated in the supporting structure when the main radiator (3) is transmitting the radio waves. In order to improve the range of the main radiator (3) and at the same time reduce its backward radiation, the supporting structure includes a secondary radiator (14) for each main radiator (3). The secondary radiator (14) has at least one break portion (12) for interrupting or breaking the high frequency currents generated therein and through the thereby interrupted flow of the high frequency currents in the supporting structure reduce deviations from the desired range and/or direction of the radio waves transmitted by the main radiator (3).

Abstract: A combination antenna for aircraft application is disclosed. The antenna has a shell similar to that of a conventional VHF communication antenna, but it houses a monopole VHF and a volute GPS antennas. Provisions are made to enable the GPS antenna to be situated beneath the VHF antenna, but yet have full view of the upper hemisphere and avoid interference even though no structural shielding is provided. The combination antenna is mountable on the pre-existing base used for the conventional single VHF communication antenna and is operable with the pre-existing cable used to transmit the signal of the replaced single VHF communication antenna.

Abstract: A radio communication device (50) has a housing having a first housing element (51) and a second housing element (53). The first housing element (51) is movable between an extended and a closed position. The radio communication device has at least two antennas (112, 113). A switch (121) is provided that is operable to switch between a first antenna (112) and a second antenna (113) responsive to position of the first housing element (51). Preferably the first antenna (112) is disposed in the first housing element (51) and the second antenna (113) is disposed in the second housing element (53) or a battery housing (57).

Abstract: A rod antenna element is connected at its lower end to one end of a coaxial impedance converter, the other end of which is connected to a feeder. A coil antenna element is capacitively coupled to the rod antenna element to provide a double resonance characteristic. When held at its retracted position, the rod antenna element, inserted in an outer conductor of the coaxial impedance converter, may preferably form an inner conductor larger in diameter than that when the rod antenna element is at its extended-out position, and the rod antenna element is connected to a coil antenna element with a low impedance.

Abstract: A combination antenna for aircraft and the like capable of transmitting and receiving VHF signals and receiving GPS signals comprising a VHF monopole antenna assembly and a GPS patch antenna assembly located within a common aerodynamically shaped dielectric housing. Separate connectors connect coaxial cables to the two assemblies and assembly elements are provided to suppress cross coupling of signal harmonics and noise from the transmitted VHF signals to enhance isolation of the received signals for the GPS and VHF functions. No adding or separation of the VHF and GPS signal information is required and the low patch antenna profile enables a low and aerodynamically shaped antenna for the beneficial use on small aircraft.

Abstract: A slot radiator and a patch radiator are formed in a single antenna which is connected to a handheld, wireless telephone. The antenna can be pivoted to operational positions and excited to radiate linearly-polarized signals or circularly-polarized signals whose radiation patterns are respectively directed azimuthally and elevationally.

Abstract: In accordance with the present invention an antenna assembly is provided whereby a satellite dish antenna and a terrestrial antenna, for receiving satellite transmissions and local broadcast television signals, respectively, are mounted in the same location. A single base mounting bracket is used to mount the antenna assembly on a wall or other structure. The satellite antenna is secure to the base mounting bracket by a satellite antenna mast. An antenna interface bracket is also secured to the base mounting bracket. A terrestrial antenna mast, upon which a terrestrial antenna is mounted, is secured to the antenna interface bracket. The antenna interface bracket includes a central portion in the shape of an elongated parallelogram. At each end of the central portion of the antenna interface bracket are mounting ends which are attached at angles with respect to opposite faces of the central portion of the antenna interface bracket.

Abstract: A diversity glass antenna for an automobile, wherein a dipole antenna is provided on a glass plate of a window of an automobile, a single pole antenna is provided at a part other than the glass plate and a stronger one of receiving signals of the dipole antenna and the single pole antenna is selected and employed, or, a diversity glass antenna for an automobile, wherein a single pole antenna is provided on a glass plate of a window of an automobile, a dipole antenna is provided at a part other than the glass plate and a stronger one of receiving signals of the dipole antenna and the single pole antenna is selected and employed.

Abstract: A multi-position antenna apparatus is provided for a device including a first housing portion and a second housing portion which are interconnected such that they move relative to one another between a collapsed position and an extended position. The device includes radio circuitry positioned in the first housing portion. The antenna apparatus includes a first antenna supported in the second housing portion. The first antenna is coupled to the radio circuitry in the extended position and in the collapsed position. A parasitic radiator is supported in the first housing portion and is only coupled to the first antenna when the housing is in the collapsed position. The parasitic radiator is a quarter wavelength of the signaling frequency or an integer multiple thereof. The parasitic radiator may include a member inductively or capacitively coupled to the first antenna when the flap is closed. Alternatively, the parasitic radiator may be a patch radiator or a loop conductor.

Abstract: A nondirectional antenna assembly, and associated method, for a radio operative at high frequencies, such as at frequencies of approximately 1.8 Gigahertz. A first antenna portion, formed of a one-half wavelength, helical winding is supported at a distal side of a nonconductive whip. A second antenna portion, comprised of a helical winding supported at a proximal side of the nonconductive whip, and a one-quarter wave helical winding, connected to radio circuitry of the radio transceiver, couples the first antenna portion to the radio circuitry. Because the first antenna portion is positioned at a distal side of the nonconductive whip, shadowing occurring as a result of positioning the radio transceiver proximate to a user during operation thereof is less likely to interfere with operation of the radio transceiver.

Abstract: A multiband phased-array antenna interleaves tapered-element radiators with waveguide radiator to facilitate the simultaneous radiation of antenna beams across a bandwidth in excess of two octaves. The launch ends of the waveguide radiators collectively define a ground plane. The tapered-element radiators have pairs of tapered wings which are extended past the ground plane by a distance which is selected to establish a predetermined tapered wing radiation impedance. The radiators of each type are spaced apart by a span which insures that they will not generate grating lobes at the highest frequency which they respectively radiate.

Abstract: A dual-band antenna in which EHF signals are connected to one end of a wauide and radiated from the other and wherein a half-dipole for VHF signals is connected to the radiating end of the waveguide and the other half-dipole for VHF is formed by a shield that is coaxial with and surrounds all of the waveguide except the radiating end. VHF signals are coupled to the half-dipole formed by the shield via a matching network.

Abstract: A broad band mobile telephone antenna comprises a first conductive circular plate and a second conductive circular plate. The first plate is located above and in parallel with the second plate. The diameter of the second plate is equal to or larger than that of the first plate. The second plate is used as a ground plate, is attached on a body of an automobile. A short-circuit rod, for matching an impedance between the first plate used as an antenna and a coaxial feeder cable for the antenna, is connected between the first and second plates. An upper end of a core rod is connected to the first plate at the substantial center thereof. A lower end of the core rod is extended toward an opening formed in the substantial center of the second plate. The opening is connected to a connector which is placed inside the automobile through an opening formed in the body. The connector connects the core rod and the coaxial cable which is connected to a transmitter/receiver of a mobile telephone system.

Abstract: A low profile polarization diversity planar antenna capable of effectively separating the horizontal and vertical polarization. The antenna combines a notch antenna (A) and a patch antenna (B) in a low profile structure. The notch antenna comprises a ground plate (10), a feed plate (20), and a radiator plate (30) which are stacked in a spaced relation. The radiator plate is shorted to the ground plate at its center and formed in its periphery with at least two radial notches (38). The feed plate carries feeder probes (27) each located adjacent to each one of the notches for feeding the notch antenna. The patch antenna comprises a patch (40) stacked above the radiator plate (30). The patch (40) is grounded at one portion thereof and has a feed point spaced from the grounded portion for feeding the patch antenna. The patch is grounded to the radiator plate and has a diameter smaller than the radiator plate.

Abstract: A convertible antenna system for enabling immediate installation of an antenna for continuing the broadcasting of conventional signals in the currently available channel ranges, but which allows for eventual convertibility to HDTV (high definition television) operation. Thus, field convertibility adjustments or modifications are made to the initially installed system after the point in time at which a channel has been assigned for HDTV broadcasting. Such channel assignment is in one of a number of possible frequency spectrum locations such as a channel adjacent to the conventional broadcast channel, or a significantly removed VHF channel, or even a UHF channel. The field adjustments can simply involve coupling or decoupling lines and associated components, or can include replacing an antenna portion.

Abstract: A diversity antenna structure and a diversity transceiver incorporating the same. Each antenna of the diversity antenna structure is formed of a first portion and a second portion. Second portions of each antenna are coupled to an electrical ground plane and form thereby ground plane portions of the respective antennas. Such second antenna portions are maintained in physical isolation from one another thereby, when receiving high frequency signals, to be maintained in apparent electrical isolation from one another. Because such ground plane portions are maintained in the apparent electrical isolation from one another, antennas of the diversity antenna structure may be positioned in close proximity to one another without causing coupling between the separate antennas of the diversity antenna structure.

Abstract: Low frequency radiating elements are embedded in a flared notch array. The flared notch array forms a series of parallel troughs in which absorptive loads are placed to reduce the antenna radar cross section. The low frequency radiating elements are embedded in the array transverse to the troughs at or below the level of the absorptive loads, and excite several troughs. The absorptive load material is absorptive in the operating band of the flared notch array, but appears as a relatively low loss dielectric at the lower frequencies of operation of the low frequency radiating elements. The low frequency radiating elements can perform Identify Friend or Foe functions in the UHF and L-band regions of the spectrum, while the flared notch array operates at X-band.

Abstract: An antenna system is described including a reflector antenna, responsive to radio frequency signals at a first frequency, having a first reflector surface, a second reflector surface and a Cassegrain feed. The antenna system further includes an array antenna having a plurality of antenna elements responsive to radio frequency signals having a second different frequency, wherein a center element is in a common location with the feed of the reflector antenna. With such an arrangement, an improved dual band antenna system is provided. By providing the center element of the array antenna in a common location with the feed of the reflector antenna, a dual band radio frequency antenna system is provided which is more compact with improved radiation characteristics than known similar configured antennas.

Abstract: A printed antenna comprises a window formed in a grounded conductor provided on one surface of an insulator substrate, a first strip conductor formed in the window, and a second strip conductor provided on the other surface of the insulator substrate.

Abstract: The present invention provides a monolithic integrated detector array for detecting both infrared, IR, and millimeter wave, MMW, energy. Elements include an integrated circuit substrate having both IR sensing elements and MMW antenna elements formed within a predetermined area thereon, said IR sensing elements including a first multiplicity of IR sensing elements substantially evenly distributed across the predetermined area of the substrate, said MMW antenna elements including a second multiplicity of antenna elements distributed over the predetermined area with individual antenna elements being located between individual IR sensing elements; and lens means substantially covering the predetermined area for collecting substantially all of the IR energy incident thereon and for distributing collected IR energy to the multiplicity of IR sensing elements, said lens means being adapted to be substantially transparent to MMW energy incident upon the predetermined area.

Abstract: A multifrequency radiating device comprising at least one radiating element (11) of a first type and at least one radiating element (12) of a second type, the elements being associated on a common surface (10) in order to constitute an array antenna. The radiating elements of the first type (16) are elements of the microstrip type and the elements of the second type (19, 20) are elements of the wire type, the radiating elements of the first type (16) acting in a first frequency range and the radiating elements of the second type (19, 20) acting in a second frequency range. The invention is particularly applicable to microwave antennas.