Abstract: A device for antennas, in particular dual-polarized microwave antennas with single-polarized patches, for which antennas reduced cross-polarization and reduced cross-coupling can be achieved without impairing the bandwidth of the antenna or increasing the occurrence of grating lobes. A modification of the traditionally rectangular geometry of the single-polarized patches is carried out. The modification is symmetrical in relation to the plane in which the linear-polarized signal lies for the respective patch. The modification involves the patches narrowing towards the ends along the respective polarization axis in such a manner that side edges which face side edges of adjacent patches are formed. In this way, the coupling between adjacent patches and also the cross-polarization in the respective patch are reduced.

Abstract: An antenna, particularly adapted to produce a scanning beam usable for radar and communication applications, includes a frame. Attached to the frame is a reciprocating device that is operatively connected to a reflecting conductor. Spaced by a uniform gap from the conductor is an elongated dielectric waveguide carried on a conductive layer of a laminate supported by the frame on an input side of the antenna. The waveguide covers a set of spaced apart apertures in the laminate conductive layer. Joined to the laminate conductive layer on an opposite output side of the antenna is a dielectric layer. On an outer surface of the laminate dielectric layer is a set of spaced apart conductive patches that align with the laminate conductive layer apertures. During operation of the antennas an electromagnetic wave is transmitted through the waveguide to pass through the laminate apertures and energizes the patches.

Abstract: A planar array antenna having radiating elements characterized by dual simultaneous polarization states and having substantially rotationally symmetric radiation patterns. A distribution network, which is connected to each dual polarized radiator, communicates the electromagnetic signals from and to each radiating element. A ground plane is positioned generally parallel to and spaced apart from the radiating elements by a predetermined distance. The conductive surface of the ground plane operates to image the radiating elements over a wide coverage area, thereby enabling a radiation pattern within an azimuth plane of the antenna to be independent of any quantity of radiating elements. Side walls, placed on each side of the array of radiators, can operate in tandem with the ground plane, to reduce the half-power beamwidth in the azimuth plane for a selected radiator design.

Abstract: In a microstrip patch antenna, multipath signals from below the horizon can be reduced by forming ground elements along the edge of the dielectric substrate. Additionally, by using lugs and capacitive elements in the patch antenna, the bandwidth of the antenna can be expanded while maintaining all other antenna characteristics as good as possible.

Abstract: The invention provides an antenna device, comprising: an antenna body including a conductor, an equivalent circuit of said conductor comprising an inductive component and a resistive component in a series connection, wherein a frequency adjusting circuit including at least a parallel circuit of a switching element and a passive element is connected to said conductor of said antenna body. The antenna body is connected in series with said frequency adjusting circuit.The invention enable to provide a compact antenna device for use in a mobile communication apparatus that performs transmission and reception on frequencies in a wide range.

Abstract: An antenna structure has a radiating element and a ground plane. The ground plane has a central region relatively closely spaced apart from the radiating element and a peripheral region extending away from the central region. The peripheral region comprises at least one conductive layer that extends radially beyond the radiating element and provides a sheet resistivity higher than that of the radiating element. Though physically small, the ground plane simulates an infinite ground plane, and the antenna structure reduces multipath signals caused by reflection from the earth.

Abstract: A wideband leaky-wave microstrip antenna having two elongated rectangular nductive patches separated by a gap on a first dielectric material and an elongated rectangular conductive coupling patch on a second dielectric material placed over the gap. The selective placement of the conductive patches and the gap formed thereby permits impedance matching resulting in a leaky-wave propagation mode. Non-radiating modes of propagation are not excited, thereby enhancing the leaky-wave mode of propagation causing radiation. This results in a relatively wide bandwidth of operation that has a main beam that is scannable as a function of frequency. The bandwidth increases substantially as the dielectric constant approaches one. The planar construction contributes to design flexibility and ease of manufacture and has many applications military and commercial communication systems.

Abstract: A rectangular-prism-shaped base member is made from a dielectric material or a magnetic material. A ground electrode and a power supplying electrode are formed on one end face of the base member with a gap disposed therebetween. At least one through hole is formed between the end face and the opposing end face. A radiation electrode is formed on the inside surface of the through hole. One end of the radiation electrode is connected to the ground electrode, and the other end serves as an open end. The power supplying electrode and the radiation electrode are electromagnetically coupled through a capacitor formed at the gap.

Abstract: An antenna (100) has a multi-mode resonating structure (110) that includes three electromagnetically coupled resonators (112, 114, 116) carried by a dielectric substrate (120). A feed system (130, 135), electromagnetically coupled to the multi-mode resonating structure (110), excites three resonating modes that operate together to produce a pass-band. Preferably, the multi-mode resonating structure (110) is formed from a wide patch radiator (112) planarly disposed between two narrow patch radiators (114, 116). The patch radiators (112, 114, 116) are simultaneously fed.

Abstract: An antenna system for use in wireless communication systems that is based on a pair of monopole antennas, which are electrically isolated from each other and arranged generally orthogonally. A feed circuit is coupled to the first and second monopole antennas, which connects them to a host system. Also, a ground plane conductor extends generally between the feeds for the first and second monopole antennas to improve isolation. The monopole antennas are formed on a printed circuit board, formed on first and second dielectric layers. A ground plane conductive film is disposed between the dielectric layers. The first monopole antenna is formed on an outside surface of the first dielectric layer, and the second monopole antenna is formed on the outside surface of the second dielectric layer. The second monopole antenna is arranged generally orthogonally to the first monopole antenna.

Abstract: An antenna structure is formed of a first patch plane, a first ground plane, a feed member plane, a second ground plane, and a second patch plane all spaced apart by layers of laminated dielectric substrate. A horn transmits energy upon the second patch plane. The energy is controlled in terms of phase and frequency, and is further electromagnetically coupled to the first patch plane which transmits in the form of shaped or pencil beams. The coupling between patch planes is accomplished by an array of slots located through the ground planes and an array of feed members interposed between the ground planes. The phase differences are established by utilization of feed members with different lengths.

Abstract: The antenna element comprises a printed circuit board (1) on one side of which is a conductive ground plane (2); and on the other side of which are two symmetrical conductive feed tracks (3,4) which excite orthogonal slot apertures (12,13, 22, 23) etched in the ground plane. Radiation from the slots induces orthogonal currents into a radiating patch (14, 18) supported in a spaced relationship with the slots. Two signals can be radiated from the patch simultaneously with 90.degree. separation in polarization. The slots radiate to the rear as well as to the front. A symmetrical conductive cavity (17, 25) enclosing the slots contains rear radiation.

Abstract: A radiating antenna capable of generating or receiving circularly polarized radiation is disclosed using a single feed and a dielectric resonator. The dielectric resonator has slightly differing dimensions along two axes. Substantially polarized radiation can be generated in each of two mutually orthogonal modes by placement of the probe at each of two locations. When the feed is situated substantially between these two locations, two orthogonal modes are excited simultaneously.

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 (1) has a radome (2) and a conducting ground plane (6) bridging between conducting end caps (4), a circuit board (5) supported on the ground plane (6), rf antenna elements (7) on the circuit board (5), opposite ends of the ground plane (6) being slidable relative to respective end caps (4) in response to thermal expansion of the ground plane (6), and the circuit board (5) being slidable relative to the ground plane (6) in response to thermal expansion of the ground plane (6).

Abstract: A phased array antenna having stacked-disc radiators embedded in dielectric media. The phased array antenna has a rectangular arrangement of unit cells that are disposed on a ground plane. A lower dielectric puck with a high dielectric constant is disposed on the ground plane. An excitable disc is disposed within the perimeter of and on top of the lower dielectric puck. An upper low dielectric constant dielectric puck that has a dielectric constant lower than that of the lower dielectric puck is disposed on the excitable disc. A parasitic disc is disposed within the perimeter of and on top of the upper dielectric puck. Dielectric filler material having a dielectric constant that is lower than that of the lower dielectric puck surrounds the dielectric pucks. A radome 18 is disposed on top of the parasitic disc and the unit cell. Two orthogonal pairs of excitation probes are coupled to the lower excitable disc.

Abstract: A receive and/or transmit microwave planar array antenna is of the multiplate stack type comprising a plurality of slot radiating elements disposed along the rows and the columns of a matrix. The basic stack comprises three ground plates incorporating openings and two independent excitation circuit planes, enabling transmission or reception of two inclined beams. At least two other excitation circuit planes are provided so that each beam can additionally have dual polarization. The excitation circuits are microstrips, coplanar waveguides, dipole lines, of the loop or slot type, or a combination of such lines. Two consecutive lines are oriented at 90.degree. to each other. Applications include individual reception from two geostationary television satellites.

Abstract: A communications antenna structure, e.g. for a cellular radio base station comprises first and second bent folded monopole planar antenna elements mounted on a ground plane and disposed generally perpendicular to thereto. The antenna elements are mutually spaced from each other and are disposed with their respective planes at an angle to each other whereby to provide both polarisation diversity and space diversity of the antenna structure.

Abstract: A glass patch cellular antenna is provided which can be imprinted as a thin film element on the interior surface of an automobile window. The antenna is physically configured to serve as a coupling element for an optional antenna mast which can be mounted externally on the window opposite the antenna. As a thin film element, the antenna can be factory installed and prewired such that the automobile is cellular ready, in that the installation of an external mast is unnecessary to achieve suitable performance. Yet, an external mast can be readily coupled with the antenna in order to enhance the performance capability of the antenna.

Abstract: A multipatch antenna including radiating patches (2) positioned on a dielectric sheet (1). The patches (2) are capacitively fed by probes (7) ending in the dielectric sheet (1) near the patches (2). By positioning the probes (7) near selected edges of the radiating patches (2), a selected polarization direction of the radiation field can be realized. By positioning several probes (7) near a radiating patch (2), a radiation field with an adjustable polarization direction or a radiation field with an extremely low cross-polarization can be obtained.

Abstract: A surface-mount antenna using a dielectric base of a relatively low dielectric constant to obtain a wide frequency band and a small size. There is also disclosed a communication device using such a surface-mount antenna. The antenna comprises a dielectric base provided with at least one hole extending through the base between two opposite end surfaces of the base. A radiating electrode is formed in the hole. One end of the radiating electrode is connected with a grounding electrode which is formed at one end surface of the dielectric base. The other end of the radiating electrode is connected with a feeding terminal via a capacitor.

Abstract: A microstrip antenna for radiating circularly polarized electromagnetic waves comprising a cluster array (20) of at least four microstrip radiator elements (22a-22d), each of which is provided with dual orthogonal coplanar feeds in phase quadrature relation achieved by connection to an asymmetric T-junction power divider (30) impedance notched at resonance. The dual fed circularly polarized reference element is positioned with its axis at a 45.degree. angle with respect to the unit cell axis. The other three dual fed elements in the unit cell are positioned and fed with a coplanar feed structure with sequential rotation and phasing to enhance the axial ratio and impedance matching performance over a wide bandwidth. The centers of the radiator elements are disposed at the corners of a square with each side of a length d in the range of 0.7 to 0.

Abstract: A penetrating microwave radar ground plane antenna system with separate arrays of transmission antenna elements and receiving antenna elements. The lengths of transmitting and receiving antenna elements are selected to enable the transmission of a nearly single-cycle pulse, the reduction of ringing between antenna elements, the reception of a signal significantly reduced in noise, and the penetration of materials having varying dielectric constants.

Abstract: A laminar patch antenna comprises a ground plane element with a cross shaped aperture sandwiched between two dielectric layers with a patch radiator on one dielectric layer and a transmission line circuit on the other dielectric layer. The transmission line circuit has linear conductors overlying respective sectors between slots of the aperture, the conductors providing a feedline and stub projection with lines of similar type overlying opposite sectors of the cross and conductors of different type overlying adjacent sectors of the cross.

Abstract: An antenna, particularly a mobile telephone antenna mounted onto the window of a motor vehicle. The antenna comprises a H-shaped ground plane turned to the horizontal plane and a vertical radiator essentially perpendicular to it and mounted at a distance from it. On each side of the vertical radiator there is at least one shadow element parallel to the vertical radiator, the said shadow elements being used to adjust the antenna's impedance to the impedance of the connecting cable to be used.

Abstract: A shortened electrical grounding system for use with a vertical antenna, particularly AM limited range information stations. The grounding system has a plurality of fractional wavelength electrically conductive members joined together and connected to the electrical ground of the transmitter associated with the antenna. The fractional wavelength electrically conductive members can be made of wire or metal panels both of which can be fanned out about the base of the vertical antenna in a substantially circular pattern. The electrical grounding system can be buried in the ground or can be used above ground as a counterpoise. The electrical conductors making up the ground system can also be incorporated into a mat made of plastic or other suitable material which can be positioned at the base of the vertical antenna.

Abstract: Contactless coupling of a low-noise block down-converter (LNB) imbedded within a flat antenna is achieved by mounting the LNB on a power summing/combining network layer of the antenna, and coupling the transition capacitively to the power summing/combining network in a stripline-to-stripline transition. The contactless coupling facilitates antenna manufacture by allowing the rapid testing of the LNB and its final assembly into the antenna.

Abstract: An antenna (105) for receiving radio frequency (RF) signals includes a conductive element (300) having a first electrical length and a first operating impedance and a transmission line (315) having a second electrical length and a second operating impedance for resonating the conductive element (300) at a predetermined operating frequency. A coaxial element (305) having a third electrical length is coupled to the conductive element (300) and the transmission line element (315) for converting the first operating impedance to the second operating impedance. When the conductive element (300) is resonated, the first, second, and third electrical lengths are substantially equal to a quarter wavelength or an odd multiple thereof at the predetermined operating frequency.

Abstract: A laminar microstrip patch antenna includes a ground plane dement having opposing first and second faces, a first dielectric planar member adjacent a first face of the ground plane element, a patch radiator on a face of the first dielectric member remote from said ground element, a second dielectric planar member adjacent a second face of the ground plane element, and a transmission line circuit for feeding the antenna. The transmission line circuit is located on a face of the second dielectric member remote from said ground plane element, and the ground plane has an aperture to couple the transmission line circuit to the patch radiator. The aperture is formed as a cross made up of two intersecting linear slots. The transmission line circuit is formed by two linear conductors intersecting each other at a single electrically insulated point, the intersection point being aligned with a center of the intersection of the aperture cross with the linear conductors lying between the slots of the aperture.

Abstract: An antenna is described including a dielectric substrate having a first and second surface and a first sheet of conductive material disposed on the first surface of the first dielectric substrate, the first sheet of conductive material having a plurality of apertures. The antenna further includes a plurality of patch radiator elements disposed adjacent the second surface of the dielectric substrate, each one of the plurality of patch radiator elements disposed diametrically opposed a corresponding one of the plurality of apertures. With such an arrangement, an antenna is provided having broader bandwidth but less feedline radiation.

Abstract: A glass antenna for a telephone of an automobile which comprises a main antenna conductor composed of a plurality of conductive strips extended radially from a junction, the outline shape of which is substantially a triangle or a sector. An insular earth conductor is disposed opposing the junction of the main antenna conductor and is disconnected with the main antenna conductor with respect to direct current. Power feeding terminals are provided on the main antenna conductor and the insular earth conductor and at least one set of the main antenna conductor and the insular earth conductor are formed at a predetermined position of a glass plate.

Abstract: A monolithically loaded microstrip antenna is provided for a communications function, such as a cellular telephone base station. The antenna includes a ground plane and a group of stacked, planar elements. A director element having a rectangular configuration together with monolithic load tabs is connected to a feed line and spaced above the ground plane. A first director element is spaced above the driven element and has lesser length and width dimensions than the driven element. A second director element is spaced above the first director element and likewise has lesser length and width dimensions than the driven element. A group of eight of the antennas are positioned in a column to form an antenna array which has substantial vertical polarization, a relatively wide horizontal beam width, approximately 60.degree. and a relatively narrow vertical beam width, approximately 8.0.degree.. The antenna array has a center frequency of 885 Mhz and a bandwidth of approximately 230 Mhz.

Abstract: A tri-band antenna including an center conducting an inner pipe surrounding the center conductor, an outer pipe surrounding the inner pipe and Teflon provided between the inner and outer pipes.

Abstract: A top loaded antenna unit is provided for concealed mounting within a vehicle below a covering or panel of dielectric material. The antenna unit includes a top load plate, a ground plate disposed in a spaced relation to the top load plate and electromagnetically coupled thereto through a matching element. The antenna unit additionally includes a dielectric member which is disposed in proximity to the top load plate for shifting resonance frequency of the antenna to a predetermined extent. The top load plate and the ground plate are assembled together with the dielectric member into a unitary structure for mounting within the vehicle below the covering or panel of dielectric material, at which condition resonance frequency of the antenna can be free from being affected from the covering or panel of the vehicle but affected solely from the dielectric member of which effect on the frequency shifting is known.

Abstract: The present invention relates to an antenna for use on a motor vehicle, particularly for cellular radio communication. The antenna comprises an elongate conductor applied to the surface of a vehicle window, the length of the antenna elongate conductor being a minor portion of the length of any peripheral side or edge of the vehicle window. A ground plane is provided along the top edge of the vehicle window, and the top end of the conductor antenna is grounded by virtue of its close proximity to the ground plane.

Abstract: A double-folded monopole is used on a linear antenna to produce a traveling-wave distribution of current. The double fold is positioned one-quarter wavelength from the end of the antenna. The resultant antenna has three radiating elements that are orthogonal with respect to each other. The orthogonal folded dipoles each consist of five segments designed so that the currents have comparable magnitudes and are in phase to provide near hemispherical coverage.

Abstract: A glass antenna for a telephone of an automobile which comprises a main antenna conductor composed of a plurality of conductive strips extended radially from a junction, the outline shape of which is substantially a triangle or a sector. An insular earth conductor is disposed opposing the junction of the main antenna conductor and is disconnected with the main antenna conductor with respect to direct current. Power feeding terminals are provided on the main antenna conductor and the insular earth conductor and at least one set of the main antenna conductor and the insular earth conductor are formed at a predetermined position of a glass plate.

Abstract: The unitary cellular telephone antenna includes a junction box to which is mounted both the antenna element, preferably a 5/8 wavelength antenna, and two 1/4 wavelength downwardly oriented radials to establish the antenna's ground plane. Electrical elements are included within the junction box to match the impedance of the antenna system to the cellular telephone transceiver and to maximize the radiated signal.

Abstract: A broadband, circular polarization antenna is disclosed for use on a satellite. In one embodiment, signals are fed to, or received by, an array of electromagnetically coupled patch pairs arranged in sequential rotation by an interconnect network which is coplanar with the coupling patches of the patch pairs. The interconnect network includes phase transmission line means, the lengths of which are preselected to provide the desired phase shifting among the coupling patches. The complexity of the array and the space required are thus reduced. In the described embodiment, two such arrays are employed, each having four patch pairs. The two arrays are arranged in sequential rotation to provide normalization of the circularly polarized transmitted or received beam.

Abstract: An antenna comprising a linear array of active elements positioned in one or more rows. The back portion of the array is partially enveloped by a reflector. The reflector includes a backwall and at least one sidewall perpendicular to the backwall and extending forward of the backwall. In one embodiment of the invention, a single row of dipole radiators form the linear array. In a second embodiment of the invention, a row of folded monopoles mounted on an imaging ground plane form the linear array. The radiation pattern is directed forward of the reflector, the back radiation in the E-plane being suppressed by the sidewall of the reflector.

Abstract: An antenna mounted on a mobile. In a first structure, a radiating element is composed of a ground plate, a vertical conductor plate and a parallel conductor plate placed on the ground plate with a predetermined space therebetween in such a manner as to have a T-shaped section and placed on the ground plate with a narrow space therebetween, and posts for connecting the edges of the parallel plate to the ground plate. Power is fed to the lower edge of the vertical conductor plate, thereby enabling a plurality of current paths to be formed in the radiating element and, hence, resonance in a wide frequency band. In a second structure, a radiating element has a conductor plate for impedance compensation in the vicinity of the feeding point of a conductor which is bent in the form of substantially a box, thereby enabling the reduction of the entire size and sufficiently increasing the length of the radiating element.

Abstract: A choke-slot ground plane and antenna system 30 is disclosed. In one embodiment the choke-slot ground plane and antenna system 30 includes a monopole antenna 44, a ground plate 36 having a plurality of concentric annular grooves 38a-c. Other embodiments include a ground plane 36 having varying size grooves to 38a-l, a ground plane having grooves having filled with dielectric material 38a'-c', a ground plate having a broadened bandwidth and having a series of first and second-type grooves 34a-c and 38a"-c", and a ground plate having a frusto-conical shape 36a and 36b.

Abstract: An antenna for radiating electromagnetic power with plural octave bandwith is formed of an array of microstrip radiating elements each of which includes a microstrip conductor element spaced apart from a ground-plane element. A common ground-plane element is employed by all of the radiators in a row of the antenna, there being a plurality of the rows disposed parallel to each other. In each radiator, the microstrip conductor element is formed of an input section which is coupled to a feed, and an output section extending to an output end of the radiator for forming a radiating aperture of the radiator. In each output section, there is a two-dimensional enlargement of a cross-section of the radiator, one dimension of enlargement being parallel to the ground-plane element, and the other direction of enlargement being perpendicular to the ground-plane element. Enlargement in the direction parallel to the ground-plane element is accomplished by increasing the width of the conductor element.

Abstract: A flat-plate antenna for use in mobile communications including a ground plate, a table-shape frame made up with a conductive top plate and connecting members which electrically connect the top plate to the ground plate, a capacitor electrode installed between the top plate and ground plate so as to resonate the table shape frame, and a strip line resonator installed under the table shape frame and is provided with a capacitor electrode for resonating the strip line resonator, the capacitor electrode being positioned beneath the central area of the top plate.

Abstract: A planar antenna of the kind comprising feed lines disposed in a flat circuit and cooperating by hyperfrequency coupling with a metal ground plane plate pierced by apertures has the feed lines presenting a termination juxtaposed with each aperture. A lower ground plane plate is disposed at a distance of approximately a quarter wavelength from the apertured metal plate. The apertured metal plate comprises a metal coating deposited on a dielectric substrate. The feed line comprise central conductors disposed in channels which open into the apertures. The array of apertures, channels and conductors can be produced on the dielectric substate by single face printed circuit techniques. The antenna may be used for the reception of direct broadcasts from satellites.

Abstract: A microstrip patch antenna assembly (20, 52, 106) is formed of a patch radiator (24, 58) and a feed structure (26, 64) of microstrip feed elements (48, 50, 66, 68) disposed on opposite sides of a ground-plane element (22, 54) and spaced apart therefrom by layers (28, 30, 72, 74) of dielectric material. A single slot (108) or a pair of orthogonally positioned slots (44, 46, 82, 84) within the ground-plane element couples linearly or circularly polarized microwave power from the feed structure to the patch radiator. Additional radiators (60, 62) may be stacked above the foregoing radiator, the radiators being separated by further layers (76, 78) of dielectric material. A plurality of square-shaped raidators (58, 60, 62) may be employed for multiple-frequency operation in which case the radiator size and the thickness of dielectric material between the radiator and the ground-plane element establish a resonant frequency.

Abstract: A microstrip line antenna generally used for receiving an electric wave from an artificial satellite, which comprises a plane dielectric substrate and a plurality of crank-shaped microstrip lines arranged on the substrate. The improvement comprises a number of half wavelength waveguide elements arranged on a plane lying parallel to the substrate in front of the microstrip lines at a predetermined distance therefrom for improving the signal-to-noise ratio of the antenna and reducing the number of antenna elements.

Abstract: A circularly polarized microstrip array antenna utilizing a honeycomb substrate made of dielectric material to support on one side the microstrip patch elements in an array, and on the other side a stripline circuit for feeding the patch elements in subarray groups of four with angular orientation and phase for producing circularly polarized radiation, preferably at a 0.degree., 90.degree., 180.degree. and 270.degree. relationship. The probe used for coupling each feed point in the stripline circuit to a microstrip patch element is teardrop shaped in order to introduce capacitance between the coupling probe and the metal sheet of the stripline circuit that serves as an antenna ground plane. The capacitance thus introduced tunes out inductance of the probe. The shape of the teardrop probe is not critical. The probe capacitance required is controlled by the maximum diameter for the teardrop shaped probe, which can be empirically determined for the operating frequency.

Abstract: A broadband omnidirectional antenna has a monopole element driven by an rf source at one end and a load at its other end consisting of insulated parallel conductors tuned to different resonant frequencies. The parallel conductors are equidistantly spaced so that transmission line coupling occurs between adjacent conductors. The parallel conductors progressively decrease in length the further away each conductor is supported from the driven element. The antenna elements can be fabricated from attached insulated wires or ribbon cable and thus the antenna can have low weight, little bulk and great flexibility.

Abstract: An array antenna system has been described incorporating a plurality of antenna elements each having two quarter wave patches or monopoles for radiating microwave energy in a forward and reverse direction, a first and second beam forming network coupled to a coupler for each antenna element, wherein microwave energy coupled to the antenna element from one beam forming network couples lagging phase to one of the two quarter wave patches and from the second beam forming network couples lagging phase to the other quarter wave patch. The invention overcomes the problem of antenna utilization by providing two autonomous beam patterns with independent control or for overcoming the problem of antenna pattern performance by providing a second pattern which may be combined with the first pattern to provide, for example, an improved front-to-back ratio.