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 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: The present invention provides an antenna including a relatively thin substantially planar electrically conductive first layer substantially lying in a first plane, and a relatively thin substantially planar electrically conductive second layer substantially lying in a second plane. The first and second layers are disposed such that the first and second planes are substantially parallel and such that they are separated by a distance d. The second layer is smaller than and overlies the first layer and defines a first region extending between the second layer and a portion of the first layer underlying the second layer. The antenna further includes a first dielectric medium having a relatively high dielectric constant and disposed in the first region, and a second dielectric medium having a relatively low dielectric constant and disposed in a second region extending between the first layer and portions of the second plane overlying the first layer and excluding the first region.

Abstract: An antenna having an omnidirectional pattern in azimuth and coverage throughout a hemisphere. The radiating elements are four half-loops mounted on a ground plane. Each half-loop is approximately one-half wavelength in length with one end grounded to the ground plane and the other end fed in opposition to the ground plane. The image produced by the ground plane of each half-loop, together with the actual half-loops give the effect of a set of four complete loops, each of which complete loops is approximately one wavelength in circumference. The elements are nominally located in planes normal to the ground plane that pass through a central point in the ground plane. The planes of the elements are oriented nominally at 90 degree intervals about a central point and the centers of the elements are offset from the central point of the ground plane by approximately one-quarter wavelength. The combination of elements produces an omnidirection radiation pattern in azimuth.

Abstract: A vehicular radio reception antenna is concealed within a body trim piece such as a spoiler or a luggage rack. A supporting body panel is utilized as a ground plane and a conductive loop is concealed within the trim piece. A transmission line connects two opposite sides of the resulting slot. Capacitors are used to connect the conducting loop to the sheet metal ground plane in order to form a dual slot/monopole antenna for receiving both FM and AM signals.

Abstract: A high-frequency signal transmission system for use as a microwave antenna or filter has a plurality of cascaded conical or planar inner conductors each having a unitary exponential gradient, a pair of circular lines or impedance-matching lines having identical dimensions and connected respectively to opposite ends of the conical or planar inner conductor for providing a predetermined characteristic impedance, and a cylindrical or rectangular tubular outer conductor covering the conical or planar inner conductor and the circular or impedance-matching lines with a cavity defined between the conical or planar inner conductor and the cylindrical or rectangular tubular outer conductor.

Abstract: An antenna for broadcast and reception of electromagnetic waves in which all or a portion of the radiating structure is formed from coaxial cable or a functional equivalent thereof in which an annular opening exists, allowing alternating electrical current to propagate onto the outer surface of said radiative structure, thereby generating electromagnetic radiation.

Abstract: Double-resonance characteristics are obtained with a small and simple construction by arranging a conductive planar radiation element approximately parallel to a conductive ground plane with an intermediary insulator, connecting a feed line to these, and further connecting a parasitic line to a separate contact point at a distance from the contact point of the feed line.

Abstract: An antenna comprises a radiating element and a cone-shaped ground plate the relative distance between which can be altered thus altering the resonant frequency of the antenna and a base. The resulting antenna is a wideband quarter-wave vertical antenna which can be employed for testing in the 1.8 GHz frequency range and for temporary use in all car phones as well as in fixed stations.

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: An antenna for mobile communication of this invention comprises a first metal plate having a slit, a second metal plate opposed to the first metal plate and electrically connected to the first metal plate, two metal foils connected to the second metal plate, and a cable for supplying feed signals to the first metal plate and the second metal plate, the cable including a first conductor connected to the first metal plate via a capacitor and a second conductor connected to the second metal plate.

Abstract: An omni-directional, collinear, vertical base station antenna having an adjustable or variable radiation beam tilt capability. Terminations at the drive or feed points are provided by an adjustable, capacitive coupling structure at the feed points between the conductive elements of a feed structure and a radiator assembly for adjusting the physical position of the feed points and thereby the phase of the feed points relative to the upper and lower portions of the antenna to alter the deflection angle of the radiation produced. A signal feed, having first and second conductive feed elements, is connectable to a signal feed line to couple a signal between the feed line and the radiator assembly.

Abstract: An antenna which comprises a plurality of spaced apart antenna segments (1-8) which are electrically isolated from each other and form a conical antenna structure, an insulator (9) disposed between each of the antenna segments, a plurality of conductors (11), each coupled to a different one of the antenna segments, for sampling a predetermined parameter at the associated antenna segment and a ground plane (10) normal to the axis of the conical structure. The antenna segments are substantially pie-shaped. In a second embodiment of the invention, the antenna segments are disposed on an electrically insulating sheet, each of the antenna segments being flared at the corner regions thereof (22) remote from the apex of the conical structure. The space between each of the segments is a slot, the slot operational as a slot antenna when the segments on opposing sides of the slot are excited 180 degrees out of phase.

Abstract: A monopole radiating blade antenna comprising a driving, high impedance stub mounted to the face of the blade that functions as part of the radiator as well as part of a shunt path between the blade and the base plate. The shunt path is completed by an air coil inductor connected between the center conductor of the stub and the base plate. One embodiment provides the input connector wire and stub in vertical alignment along the center vertical axis of the blade. Another embodiment arranges the stub to be off-set from the input wire. Some advantages over conventional blade antennas include increased gain at low angles of elevation above the horizon, good impedance match over a wide range of frequencies without using conventional 1/4 wave length stub matching that can introduce dielectric losses, low resistance to ground to bleed off static electricity and lightning, non-loading of the high impedance path at design frequencies, and good accommodation of 5/8 wavelength radiator blade dimensioning.

Abstract: An M-type car antenna for traffic information communication systems including an antenna element having a length which is one-half of the wavelength of the radio way used in the information communication systems, and a connector which is connected via an electrostatic coupling to the center-of the antenna element, the impedance matching and feeding being carried out by the connector. In this antenna, the voltage polarity of the connector at the coupling point and that of the center of the antenna element are set to be opposite from each other, and the electric current in the antenna element and that in the connector are set to be in the same direction. Thus, the M-type antenna is compact and easy to manufacture with stable antenna characteristics.

Abstract: An antenna apparatus for receiving two distinct frequencies in the MHz or GHz range. A patch layer of electrically conducting material is positioned in the interior of a dielectric layer that has top and bottom surfaces. First and second ground planes are positioned on the top and bottom surfaces of the substrate, respectively. The patch is electrically connected by plated via holes to an annular strip of conducting material, positioned on the top substrate surface and surrounding the first ground plane. A patch antenna for receiving a first frequency is thus formed by the patch layer and the second ground plane. A cavity antenna for receiving a second frequency is formed from the patch layer, the first ground plane, and the annular strip. Two receiver feed connections, positioned at selected first and second positions on the patch resonator, receive distinct first and second frequencies.

Abstract: In order to perform feeding to an inverted F antenna having a plate conductor of an approximately rectangular shape for forming a radiation conductor and a ground conductor arranged in parallel with the place conductor, a strip conductor plate connected to a feeder line is provided on the ground conductor via a dielectric substrate. Hence, the feeding from the feeder line to the inverted F antenna 37 is performed by an electric field coupling of the plate conductor and the strip conductor plate. The inverted F antenna and a resonator are integrated by coupling means to carry out an impedance matching, and the inverted F antenna and the resonator 62 constitute a band pass filter.

Abstract: A planar antennas has a square radiating conductor with a total of eight slits defined therein. Each of the slits extends from one side of the radiating conductor parallel to opposing sides flanking the one side. The slits are positioned such that they slits remain in the same pattern when the radiating conductor is turned 90.degree.. Any changes in the impedance as the offset length of a feeding point from the center of the planar antenna are relatively small, specifically range from 0 ohm to 400 ohm. The planar antenna is small in size, is easy to achieve impedance matching with a general feeding system having an impedance of 50 ohms, for example, and has wider frequency band. The planar antenna is also capable of generating circularly polarized electromagnetic waves.

Abstract: A crossed-slot antenna having a reduced number of feed components to achieve circular polarization. The present invention provides a crossed-slot antenna capable of transceiving circularly polarized radiation and having a feed network comprising a ninety degree hybrid and at least one infinite balun. In one embodiment, a transmission line is used to feed a pair of antenna patch elements, one of which acts as a local ground plane for the microstrip line, thereby defining an infinite balun. The transmission line may comprise a microstrip line, the inner conductor of a coaxial cable, or a coplanar waveguide.

Abstract: An antenna for transmitter and receiver of a portable radio appliance (cordless telephone, mobile telephone, pager, telepoint appliance and so forth) essentially consists of two sheet-metal angles (2,3) which are arranged adjacently to one another. One of the two elements is excited with radio-frequency currents by means of a coaxial feedline (4). The second sheet-metal angle (3) is excited by parasitic coupling from the first sheet-metal angle (2). The sheet-metal angles (2,3) are identically oriented and the distance between them is much shorter in the end area than at the bending edge of the apex line. This results in high reactive currents and low impedance. The antenna can also be modified by feeding both sheet-metal angles (2,3), dividing it into two identical part-antennas or several sheet-metal angles. The sheet-metal angles can consist of metal foils which are applied to a plastic housing. In addition, an embodiment with wire angles is also possible.

Abstract: Planar serpentine antennas disclosed include a generally flat, non-conductive carrier layer and a generally flat radiator of a preselected length and arranged in a generally serpentine pattern that is secured to a surface of the carrier layer. One form of the antenna disclosed that is particularly suited for vehicle transceivers and mounting on a vehicle window in a stick-on fashion has a series of change of direction points characterized by a succession of right angle turns and back folds to obtain substantially the greatest length in the smallest surface area. Another form of the antennas disclosed that are particularly suited for AM/FM radios, stereos, etc. have a sinuous pattern with radiator sections in parallel spaced relation to one another and further are connected at opposite ends in curved back folds.

Abstract: The present invention provides a microstrip antenna that includes a microstrip element with an integral member which is used to establish an electrical connection between the microstrip element and a transmission line. The use of the integral member to establish this electrical connection yields advantages in performance, reliability, and manufacturing, among others, that make the microstrip antenna particularly suitable for mobile applications. The present invention also provides a method of manufacturing such a microstrip antenna.

Abstract: A means for concealing an antenna within an extension of a common roof structure using an electrically shortened element laminated between two layers of non-RF conductive material which add to the strength of the invention as well as concealability. The antenna itself comprises a vertical radiator and a helical counterpoise of metal strip, wire, or deposited metal fed at the center point. The entire antenna is housed between laminated layers of plastic in the form of a vent pipe.

Abstract: In order to provide a broad-band non-grounded type ultrashort-wave antenna which has sufficiently high sensitivity characteristics and broad-band VSWR characteristics even in an expanded frequency band, is able to use a small-diameter antenna element, is light in weight and simple in structure, and can be manufactured inexpensively, an antenna element parallel resonance part, that is formed by the inductance and distributed capacitance of the rod-form antenna element which has an electrical length close to lambda/2 or an integral multiple of lambda/2, and a metal member parallel resonance part, that is formed by the electrostatic capacitance between first and second metal members which are installed parallel to each other and have respective electrical lengths of lambda/4 and the inductance of the first metal member, are electrostatically coupled by the stray capacity that exists between the antenna element and an electrostatic coupling piece projected from the second metal member, thus forming a double-tuned

Abstract: Antenna apparatus for receiving two distinct frequencies in the MHz or GHz range. A resonator layer of electrically conducting material is positioned in the interior of a dielectric layer that has first and second opposed surfaces (front and back). First and second ground planes are positioned on the first and second opposed surfaces of the substrate. The resonator is electrically connected to an annular strip of conducting material, positioned on the first substrate surface and surrounding the first ground plane. Two receiver feed connections, positioned at selected first and second positions on the patch resonator, receive distinct first and second frequencies. This apparatus may be used to receive the two GPS operating frequencies, the two GLONASS operating frequencies or two wireless LAN operating frequencies.

Abstract: A microstrip antenna capable of dual-frequency operation. The antenna comprises a microstrip having a thin, rectangular metal strip that is supported above a conductive ground plane by two dielectric layers which are separated by an air gap or other lower dielectric constant material. Conducting side walls and a rear wall extend between the ground plane and the strip. The ground plane, the strip, the walls and an opening at the front cooperate to form a rectangular resonant cavity. In essence, the cavity is surrounded by conducting surfaces except for the front opening and a small opening in the ground plane that accommodates an antenna feed. The front opening of the cavity functions as an antenna aperture through which the antenna transmits and/or receives energy. The antenna feed is a coaxial transmission line that provides a means for coupling the antenna to an external circuit. The spaced dielectric layers and the air gap produces higher-order modes which causes dual frequencies.

Abstract: A vehicle antenna for a cellular telephone has a balanced-unbalanced (BALUN) transformer that is connected to the telephone and is coupled to a horizontally polarized antenna on the interior of the vehicle and to a vertically polarized antenna that is located on the exterior of the vehicle. The vertically polarized component of a received signal is combined with the horizontally polarized component of the same signal in the transformer element and is applied to the cellular telephone. Signals to be transmitted are applied to the the transformer element and are divided into two portions, one of which is applied to the vertically polarized antenna and the other of which is applied to the horizontally polarized antenna. Because signals from a remote cellular transmitter cell arrive with both a vertical and a horizontal component, the antenna of the present invention retrieves the horizontal component which would otherwise be lost and combines it with the vertical component for more reliable signal reception.

Abstract: A flat-plane antenna for mobile communications, used in automobiles, etc. including a table form antenna element made up of a conductive flat-plate section and a plurality of leg sections which connect to the flat-plate section to a ground plate, a strip line resonator provided beneath the table form antenna with a space in between, and a capacitor electrode provided on the strip line resonator directly under the center of the table form antenna element. A feeding line is connected to the strip line resonator.

Abstract: A circular polarization antenna whose radiation pattern is in the shape of a body of revolution about an axis and has a radiation minimum in the direction of this axis comprises a reflective conductive surface which is essentially in the shape of a body of revolution about the axis. A rectilinear conductive rod extends axially from a first end at the level of and isolated from the conductive surface to a second end and is connected at its first end to an excitation line. A plurality of radiating arms each have a first part extending in an essentially radial plane from the second end of the conductive rod. This first part is electrically connected at its proximal end direct to the conductive rod and is extended at its distal end by a curvilinear rod typically lying on the surface of a sphere centered at the second end and whose general direction is inclined relative to the radial plane.

Abstract: A low profile antenna includes a rectangular driven element and a rectangular ground plate spaced from the driven element. A coaxial transmission has its center conductor connected to an end of the driven element and its ground connection connected to the end of the driven element spaced from the center conductor connection. An inductance is coupled between the coaxial cable shield and the ground plate.

Abstract: An antenna comprises a base plate forming a ground plane, a coaxial feed serving as a mast connected to the base plate and extending along an axis that is normal to the ground plane, and two orthogonal dipoles each formed of two elements. Each dipole element has a first end connected to and supported by the mast at a first location spaced apart from the ground plane by a predetermined distance and a second end closer to the ground plane and exhibits a curvature in a plane containing the mast.

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: In the microstrip antenna apparatus according to the present invetnion, a circular radiation element is provided on a grounded conductive planar element through a dielectric layer having a small dielectric loss, and this radiation element resonates in the TM.sub.01 mode. A feed point is located at substantially the center of the circular radiation element, and an impedance matching device is interposed between the feed point and a coaxial connector. The inside conductor of the impedance matching device is connected to the feed point to supply energy to the radiation element, and an outside conductor is connected to substantially the center of the conductive planar element so as to be grounded. Further, this antenna is provided on the microstrip antenna at its topmost portion in which a plurality of conductive planar elements are stacked thereby forming the microstrip antenna which is applicable to a plurality of frequencies.

Abstract: A log periodic antenna of simple, circuit board construction exhibits an average standing wave ratio of less than 2.0 over a broadband frequency characteristic.

Abstract: A microstrip antenna includes an annular conducting element spaced by a dielectric element from a conducting ground plane and radiating circular polarization in a conical elevation pattern. A central whip antenna may be located on the axis of the annular-shaped element. Another microstrip antenna having an annular conducting element may be dielectrically spaced from the first-mentioned annular conducting element that comprises the ground plane for the second annular-conducting element.

Abstract: A multi-resonant antenna is formed by a plurality of resonators which resonate at different frequencies. A feed member is coupled to the multi-resonant resonators. Disposed between and separating the resonators from the feed member is a dielectric substrate.

Abstract: An planar antenna for use with a cellular telephone has a dielectric substrate with conductive coatings on its two major surfaces. A coaxial cable extends through a central aperture in the substrate with a shield of the cable connected to coating on one surface and a center conductor of the cable connected to coating on the other substrate surface. A number of shunts extend through the substrate electrically connecting the coatings on the two surfaces at points along a line that runs through the central aperture. Another shunt extends through the substrate electrically connecting the coatings on the two surfaces at a point which is not along the line of the other shunts. The position of the last shunt is non-uniformly spaced with respect to the other shunts and is selected to alter an electrical characteristic of the antenna to a desired value.

Abstract: An FM wave antenna including a coaxial cable, a parallel conductor which are provided parallel to a metal conductor such as a vehicle body and an amplifier provided between the coaxial cable and the parallel conductor. The coaxial cable is made up of a central core and inductive outer sheath and one end of the inductive outer sheath is connected to the metal conductor, and one end of the parallel conductor is also connected to the metal conductor. The amplifier amplifies signals from the parallel conductor and inductive outer sheath of the coaxial cable and outputs amplified signals to the central core of the coaxial cable.

Abstract: A plane patch antenna including patch and earth conductive plate members maintained in spaced-parallel relation to each other. A feeder shaft extends from the patch plate member for electrical connection of the patch plate member to a lead wire. The feeder shaft has a tapered portion extending from the patch plate member toward the earth plate member. The tapered portion has a cross-sectional area decreasing as going away from the patch plate member.

Abstract: A patch antenna is formed of one or more flat disc-shaped radiators disposed parallel to and spaced apart from a common ground-plane element. At each radiator, there is a feed assembly of two feeds positioned to one side of a center of the radiator in space quadrature and excited in phase quadrature for generating circularly polarized radiation from the radiator. Each of the feeds, in a preferred embodiment of the invention, is formed as a post extending through an aperture in the ground-plane element partway to the radiator for capacitive coupling with the radiator. At each radiator, a reactance element on the form of a capacitive block extends from the ground-plane element partway to the radiator at a location diametrically opposite the feed assembly.

Abstract: A microstrip antenna has a rectangularly-shaped radiation conductive plate attached to one side of a dielectric plate, with a grounding conductive plate being attached to the other side of the dielectric plate. Rectangular line loads extend from adjacent sides of the radiation conductive plate. With such a configuration, the antenna retains all of the advantages of a microstrip antenna, including light weight, compactness, ease of manufacture, and a low profile, while enabling operation at multiple frequencies (four, on one embodiment), or polarization at multiple frequencies (two, in another embodiment).

Abstract: An inside antenna is provided comprising a housing, a capacitor and an inductor located within the housing and cooperating to form an LC network, a radiator connected to the inductor, and a coaxial cable with its central conductor tapped to a selected location of the inductor. The capacitor is formed by a radiator plate to which the radiator and inductor are connected and a ground plate. A set screw is carried by the housing and engages the ground plate so that movement of the set screw varies the position of the ground plate relative to the radiator plate.

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.

Abstract: A low-profile patch radiator for use in an array antenna has a multilayer structure which includes a double-tuned impedance matching network and balun and a coaxial feed for linear polarization of the radiated waves. A second embodiment further includes a second double-tuned impedance matching network and balun and a second coaxial feed for dual polarization operation. The matching networks/baluns, which comprise microstrip circuits on Duroid substrates, increase the frequency bandwidth of the patch radiator.

Abstract: An antenna to be mounted on a vehicle. The antenna includes a ground plate with an L-shaped radiator plate and an L-shaped sub-radiator plate. One leg of the radiator plate and sub-radiator plate are parallel to the ground plate. The parallel legs are spaced from the ground plate. The other leg is perpendicular to the ground plate. The perpendicular leg is separated from the ground plate by a small gap. The two legs are opposed to each other with a gap between the legs parallel to the ground plate. In some embodiments, filler is placed between the plates.

Abstract: The invention relates to matching asymmetrical discontinuites in transmission lines to give low reflection coefficients (less than five percent) over a wide frequency band (corresponding to at least an octave in wavelength). A group of asymmetrical discontinuites, such as impedance steps in a waveguide, are matched by considering a reference plane whose position varies with frequency at which the reflection coefficient for waves transmitted in one direction is equal to that for waves transmitted in the opposite direction. Matching elements are then provided which have a reflection coefficient at the reference plane which is equal and opposite to the reflection coefficient of the discontinuities. Matching is less difficult if the distance between the steps is less than a quarter of a guide wavelength at all frequencies in the wide band mentioned above and such an arrangement is a "reduced quarterwave transformer".

Abstract: The subject invention relates to antennas having substantially greater bandwidth and low angle gain of the type for the transceiving of circularly/elliptically polarized electromagnetic waves. The antenna structure comprises a ground plane, a source of linearly-polarized wave energy field associated with said ground plane, and a plurality of conductive elements having an L-shape, said elements equally spaced from one another and equiangularly disposed about the sources, said plurality of elements being in a form of a circular arrangements, each element being so disposed as to fall on the circumference of the circular arrangement, each element lying in a common plane orthogonal to the linearly-polarized wave energy field provided by said source. The subject invention has special utility in motor and marine craft for communication and navigation.

Abstract: A discone antenna has a conducting cone having an apex and a conducting disc with a disc feed conductor extending from its center. The conducting disc is mounted at the apex of the cone in spaced relation therewith such that the disc feed conductor extends down into the cone through the cone's apex. A coaxial connector is mounted within the cone at the apex of the cone and defines a tuning cavity therein. A tuning slug is received in the tuning cavity through the apex of the cone and is vertically adjustable within the tuning cavity to tune the antenna.

Abstract: A plane antenna comprises a power-supply circuit, a radiator circuit and an earthing conductor which are stacked respectively with a dielectric layer interposed between them, in which the power-supply and radiator circuits are made independent of each other as electromagnetically coupled to each other and at least one of the dielectric layers is formed with a foamed resin, whereby insertion loss can be reduced to remarkably improve the antenna characteristics. Only with the interposition of the foamed resin dielectric layer or layers, an effective separation is achieved between at least the power-supply circuit and the earthing conductor or the power-supply circuit and the radiator circuit, for a large extent improvement in the assembling ability.

Abstract: An antenna is disclosed which is particularly suitable for use with a cellular mobile phone. The antenna may be mounted on the rear window of a vehicle, and it includes a current fed one-quarter wavelength radiator adapted for mounting on one side of the window. An electrically conductive inner transfer member is mounted on the inside of the window in alignment with the radiator and a pair of spaced field-cancelling conductors are attached to the inside of the window and are spaced from the inner transfer member. The central conductor of an RF coaxial cable is coupled to the inner transfer member and the surrounding ground conductor of the coaxial cable is coupled to the field-cancelling conductors. In one embodiment, the one-quarter wavelength radiator comprises a pair of parallel, spaced radiator elements. RF energy is transferred through the vehicle window and the drilling of a hole for coupling the radiator to the coaxial cable is unnecessary.