Abstract: A reception antenna is formed of a column-profiled ferrite core and three antenna coils, each of which is formed by winding electric wire around the core. Each central axis of the three antenna coils is mutually disposed orthogonally at a barycenter of the core. Each of the three antenna coils is symmetrical with respect to the barycenter. A third antenna coil and each of a first antenna coil and a second antenna coil are overlapped with a space. The first antenna coil and the second antenna coil are overlapped with direct contact, where a starting end of the second antenna and a terminating end (outward end) of the first antenna is connected.

Abstract: A remote access device which may comprise an antenna having a first inductor with a first axis, a second inductor with a second axis, and a third inductor with a third axis, where the first, second and third axes may be oriented substantially perpendicular to each other, respectively, such that the first inductor generates a first magnetic field associated with a first plane, the second inductor generates a second magnetic field associated with a second plane different than the first plane, and the third inductor generates a third magnetic field associated with a third plane different than the first and second planes. The remote access device preferably includes a single form for the first, second and third inductors, where the first, second and third inductors are each wound on the form.

Abstract: The invention concerns an RF-type contactless chip card, comprising a sensor coil (1), an electronic circuit (2) connected to the coil and an antenna (3) made form a material with high magnetic permeability, including a first part located substantially in the plane of the coil upper surface (A), a second part located substantially in the plane of the coil lower surface (B) and a connecting part (C) located in the center of the coil. The latter part is dimensioned relative to the antenna (3) such that the voltages induced at its terminals are of the same order of magnitude, whether the antenna is parallel or perpendicular to the lines of flux generated by a reader.

Abstract: A portable receiver comprised of several antennas that are connected to a receiver unit for receiving a signal transmitted by an electromagnetic induction process. The antennas are made in the form of coils, that are carried by a support in such a way that the respective turns of the coils are oriented along different respective axes of an axis system associated with the support. The invention further includes a phase shifting means oriented between the antennas and the receiver unit. The phase shifting means is designed to produce a temporal phase shift corresponding to an angle of (n−1)&pgr;/n, at the frequency of the signal received between induced signals delivered by the antennas (n being the number of antennas).

Abstract: An antenna is comprised of a core portion laminated by a magnetic ribbon through a deformable member and a coil portion wound around the core portion.

Abstract: A communication device has at least one transmitter and/or receiver, an energy storage, and a signal coupling connecting the transmitter and/or receiver with the energy storage for transmitting and/or receiving a radio signal.

Abstract: A printed circuit antenna with broadband input coupling is disclosed. An elongated conductive antenna element arranged in the form of a loop is disposed on a dielectric substrate formed on a ground plane. The antenna element has first and second adjacent end portions separated by a gap. The second end portion is connected to the ground plane. An input coupler is provided for matching an input impedance of the antenna to the antenna feed circuitry. The input coupler can comprise a conductive line disposed on the substrate adjacent to the antenna element. The conductive line is separated from the antenna element by a coupling space for coupling to the antenna element an input signal applied to the input coupler. The conductive line extends parallel to a portion of the antenna element including the first end portion. The arrangement has the advantage of having an input impedance that is relatively insensitive to adjustments affecting the antenna center frequency.

Abstract: A loop antenna system. The loop antenna system for a wireless transmission device having a signal end and a ground end, includes a loop antenna having a toroidal helix wire with a first end coupled to the signal end and a second end coupled to the ground end.

Abstract: An antenna device includes a door handle provided inside of a vehicle door for opening the vehicle door, and an antenna provided inside of the door handle and generating a magnetic field component in a direction different from a perpendicular direction to an outer surface of the vehicle door.

Abstract: An antenna for a transponder comprises a magnetic core composed of layered amorphous metallic thin plates or composite plates of soft magnetic flakes and a synthetic resin, and a coil wound on the magnetic core. A transponder comprises two antennas set forth above, and a spiral antenna.

Abstract: An antenna, and method for forming the same, is provided that receives or transmits three (3) components of low frequency magnetic fields while having physical dimensions that can be easily housed inside a slim borehole tool. The antenna includes a permeable core and a plurality of sets of windings of conductive wire surrounding the permeable core, with each set of plurality of sets having a cross-sectional area associated therewith, with the cross-sectionals of the remaining sets. Typically, the cross-sectional area of each of the plurality of cross-sectional areas extends orthogonally to the cross-sectional areas of the remaining cross-sectional areas of the plurality of cross-sectional areas.

Abstract: The invention relates to a sensor of the type that comprises a system of co-localized antennae, itself comprising at least two active antennae (1) with the same phase center, said antennae being placed at the top end of a mast (4) and connected to down conductors (3). According to the invention, said mast (4) is produced from a dielectric material in such a way as to enable the antennae to be decoupled. The sensor also has filtering means (51 to 5n) which are arranged on at least one of said down conductors.

Abstract: A receiving antenna is formed by disposing two ferrite chip antenna elements adjacently to each other. The two ferrite chip antenna elements are disposed in combination so that a magnetic flux passing through the central axis of one of the ferrite chip antenna elements does not pass through that of the other of the ferrite chip antenna elements. Herein, the two ferrite chip antenna elements are disposed in combination so as to intersect each other substantially at right angles in a state in which one end portion of one of the ferrite chip antenna elements is opposed to a side surface portion of the other of the ferrite chip antenna elements.

Abstract: A remote access device which may comprise an antenna having a first inductor with a first axis, a second inductor with a second axis, and a third inductor with a third axis, where the first, second and third axes may be oriented substantially perpendicular to each other, respectively, such that the first inductor generates a first magnetic field associated with a first plane, the second inductor generates a second magnetic field associated with a second plane different than the first plane, and the third inductor generates a third magnetic field associated with a third plane different than the first and second planes. The remote access device preferably includes a single form for the first, second and third inductors, where the first, second and third inductors are each wound on the form.

Abstract: The present invention is an antenna with a cubic core. A first conductor is wound around the core's first axis. A first dielectric layer is placed around the first conductor. A first electrical shield is placed around the first dielectric layer. A second dielectric layer is placed around the first electrical shield. A second conductor is wound around the second dielectric layer in the core's second axis. A second electrical shield is placed around the third dielectric layer. A fourth dielectric layer is placed around the second electrical shield. A third conductor is wound around the fourth dielectric layer in the core's third plane. A fifth dielectric layer is placed around the third conductor. A third electrical shield is placed around the fifth dielectric layer. Each conductor is connected to an amplifier. Each amplifier is connected to an anti-aliasing filter. Each anti-aliasing filter is connected to an analog-to-digital converter.

Abstract: A passive, non-multiplexed, two-axis antenna for sensing time-varying magnetic fields of a particular carrier frequency at a second point in space as produced by a electromagnetic field generator located at a first point in space. The antenna has a particular sensitive plane and produces a single output signal having amplitude proportionally related to the magnitude of the incident magnetic field's vector projection onto the antenna's sensitive plane. If the phase of the magnetic field is known, then the antenna's signal is processed to obtain the incident magnetic field's vector components. The antenna enables the realization of two- or three-axis magnetic field receivers with reduced signal processing complexity, cost and power requirements.

Abstract: A ferrite core antenna having two spaced signal pick-up coils coupled through a transformer so that the signals from the two coils are additively combined in the primary of the transformer. A variable capacitor connected to the two coils tunes the antenna to selected frequencies. This results in amplification of the signal.

Abstract: A transmission/reception radio-wave aerial for an interrogation device for electronic labels carried by objects, the transmission/reception radio-wave aerial being tuned to an F0 frequency and each electronic label including a radio-wave aerial tuned to the F0 frequency and being associated with an electronic circuit, wherein the transmission/reception radio-wave aerial is arranged to create a magnetic field which modifies the tuning frequency for the radio-wave aerials for the electronic labels in such a way to retune towards the F0 frequency of the aerial of the interrogation device.

Abstract: The invention concerns a chip card associated with RF transmission means. Said chip card comprises on each surface high permeability zones arranged so as to concentrate the flux generated by the RF transmission means onto a sensor coil. To ensure the proper functioning of the system, the transmission means generate flux lines parallel to the surface of the chip card.

Abstract: An apparatus for, and method of, replacing conventional antennas which transmit radio frequency energy from radio frequency transmitters. The invention provides for the use of any conductive surface as a transmitting antenna by taking advantage of the fact that any electrical conductor or surface that is 0.1 wavelengths or longer will radiate RF energy when injected with sufficient current. The RF current injecting antenna device, employing the principles of an instrument transformer, couples RF energy from a transmitter to a linear conductive element or a conductive surface. The useful frequency range that has been demonstrated for the device is 2 MHz to 1 GHz.

Abstract: A passive integrated transponder (PIT) tag comprising an integrated circuit and a unitary core is described. The unitary core comprises a coil-forming portion proximate one end thereof and an integrated circuit support portion proximate an opposite end thereof. The integrated circuit support portion extends beneath and supports the integrated circuit.

Abstract: A method and apparatus for time domain reflectometry sensing of moisture in a test material. The sensor (200) having a generally helical shaped electrode (206) and at least one secondary electrode (208) spaced apart from the generally helical shaped electrode (206) to enable the test material to be present in the space (210) between the helical shaped electrode (206) and the secondary electrode (208). A wave pulse generator (202) is coupled to the generally helical shaped electrode (206) and the secondary electrode (208) that results in a reflection of the generated wave from the wave pulse generator (202). Additionally, a reflected pulse detector (204) is coupled to the generally helical shaped electrode (206) and the secondary electrode (208), in which the reflected wave pulse detector (204) receives a reflected wave pulse from the wave pulse generator (202).

Abstract: A remote access device which may comprise an antenna having a first inductor with a first axis, a second inductor with a second axis, and a third inductor with a third axis, where the first, second and third axes may be oriented substantially perpendicular to each other, respectively, such that the first inductor generates a first magnetic field associated with a first plane, the second inductor generates a second magnetic field associated with a second plane different than the first plane, and the third inductor generates a third magnetic field associated with a third plane different than the first and second planes. The remote access device preferably includes a single form for the first, second and third inductors, where the first, second and third inductors are each wound on the form.

Abstract: Antennas with steerable antenna patterns and techniques for using such antennas are described. In accordance with the invention, antenna patterns with one or more NULLs are used. Through the use of digital control signals the antenna pattern is steered so that a source of signal interference, e.g., a multipath signal, will be located in a NULL. In this manner the received signal's S/N ratio can be maximized thereby facilitating demodulation. The techniques of the invention can be applied to television, computer devices, mobile devices and a wide range of other systems. Digital commands to control an antenna may include multiple information fields, e.g., a direction field, a channel field, a gain field and a polarity field. Antennas incapable of supporting the specified fields disregard information in fields which are not supported. Information in each supported field is decoded and used to adjust the corresponding antenna characteristic.

Abstract: A passive integrated transponder (PIT) tag comprising an integrated circuit and a unitary core is described. The unitary core comprises a coil-forming portion proximate one end thereof and an integrated circuit support portion proximate an opposite end thereof. The integrated circuit support portion extends beneath and supports the integrated circuit.

Abstract: A bar antenna includes a single body ferromagnetic substance core, a bobbin which accommodates the core in a hollow space and has a plurality of coil windings, a case in which is positioned the core and the bobbin, and a potting material in the case and/or the bobbin. The potting material isolates the core from temperature changes, humidity changes and vibration.

Abstract: A radio unit for computer systems for receiving and/or presenting data information transmitted within a commercial broadcast band and methods of manufacturing and using the same. The radio unit comprises an integrated antenna system, a first radio receiver, and an interface system for removably connecting the radio unit to a computer system. The integrated antenna system includes a first set of windings, a second set of windings, and a ferrite core with a first region and a second region. To reduce parasitic capacitance among the windings, the first set of windings are wound substantially in a first direction about a circumference of the first region, and the second set of windings are wound substantially in a second direction, substantially opposite said first direction, about a circumference of the second region and are coupled with the first set of windings at a junction between the first region and the second region.

Abstract: An EAS activation/deactivation antenna in accordance with the invention comprises a core; a coil arrangement having at least two coils spirally wrapped about the core, the first coil having a first rotational direction and the second coil having a rotational direction counter to the first rotational direction; and, a current source operatively connected to the coil arrangement. In consequence of the inventive arrangement, a decaying or steady state, alternating or direct current supplied by a current source can excite the coil arrangement to produce a significant near magnetic field and a reduced far magnetic field, for activation or deactivation of EAS markers.

Abstract: A bar antenna includes a single body ferromagnetic substance core, a bobbin which accommodates the core in a hollow space and has a plurality of coil windings, a case in which is positioned the core and the bobbin, and a potting material in the case and/or the bobbin. The potting material isolates the core from temperature changes, humidity changes and vibration.

Abstract: A chip antenna simple in structure, producing small variation in antenna characteristics between individual antennas, requiring no circuit adjustments, excellent in productivity, and capable of being mounted on a circuit board, as well as a wireless terminal using the same and a method of fabricating the same. A core body is made from an insulating material in a quadrangular or circular cylinder shape. A conductor in a helical shape is mounted on the side surface of the core body. A terminal portion is provided on the core body and electrically connected with an end portion of the conductor. The width, depth, and height of the core body are within ranges of 0.5-5 mm, 0.5-5 mm, and 4-40 mm, respectively. Intrinsic volume resistance and relative dielectric constant of the material are 1013 &OHgr;·m or above and 40 or below, respectively.

Abstract: A ferrite core antenna having two spaced signal pick-up coils coupled through a transformer so that the signals from the two coils are additively combined in the primary of the transformer. A variable capacitor connected to the two coils tunes the antenna to selected frequencies. This results in amplification of the signal.

Abstract: The invention concerns a transponder arrangement in which the transponder is disposed on a conductive surface. According to the invention, the coils forming the transponder antenna are aligned at a slight distance from the metal surface with their main magnetic field direction parallel to this surface.

Abstract: A downhole magnetic hollow core dipole antenna has a high permeability material magnetic core composed of laminated sections placed around a section of drill pipe and running substantially along the length of the pipe. The magnetic core is then surrounded by electrically conductive windings, which in turn are surrounded by a protective sleeve which, if conductive, is split to prevent power-robbing eddy current generation.

Abstract: An antenna device including a loop antenna main body having a predetermined aperture area, and a conductor element insulated from the loop antenna main body, connected to a ground potential, and formed in parallel with the loop antenna main body.

Abstract: An optically controlled frequency selective surface (FSS) includes an electrically conductive layer having an array of radio frequency scattering elements such as slots formed in an electrically conductive layer or loops mounted to a substrate. Photonically controlled elements, such as photo-diodes, photo-transistors, and other photo-electronic devices, are connected across each of the scattering elements. Electromagnetic characteristics of the FSS, including resonant frequency, impedance, and the pass/stop band, may be modulated by controlling the degree of illumination of the photonically controlled elements.

Abstract: First and second spaced apart in-phase current loops at least partially overlap in the axial direction. The first and second current loops may be first and second arrays of in-phase current loops that are spaced apart and at least partially overlap in the axial direction. First and second arrays of arrays also may be provided that are spaced apart from one another and that at least partially overlap in the axial direction. Desirably high mid-field strength may be provided without violating guidelines for far field radiation in the axial direction or in the plane of the loops. A third array of in-phase current loops, an array of third in-phase current loops and/or an array of arrays of third in-phase current loops also may be provided that spaced apart from and at least partially overlapping the second loops in the axial direction, opposite the first loops.

Abstract: A shielded magnetic-field antenna has at least one turn of a metallic element and metallic tubular shielding positioned around the element. The turn (3a) is produced in a printed circuit on a card made of insulating material (4a). The shielding has two open rings (5a, 6a) each produced in a printed circuit and disposed respectively on a bottom card (9a) and a top card (10a) made of insulating material. The cards are assembled by gripping the turn between the top and bottom cards. A plurality of metallic vias (7a, 8a) connect side edges of the two rings. The vias extend through the cards, and are positioned around the turn.

Abstract: A wrist band for a device main body containing communication circuits, having a first wrist band at least partially covering a first antenna plate, a second wrist band at least partially covering a second antenna plate, and a clasp device including a contact mechanism for electrically connecting the first antenna plate and the second antenna plate to form a loop-like antenna when the second wrist band and first wrist band are clasped. The clasp device is releasable and has a three-fold stricture. The clasp device includes a clasp lower plate having a base end portion fixed to the first wrist band, a clasp intermediate plate connected to the clasp lower plate, a clasp upper box connected to the clasp intermediate plate and fixed to the second wrist band and a clasping lock mechanism that fixes the clasp upper box to the clasp lower plate when the clasp intermediate plate is rotated and overlapped onto the clasped lower plate.

Abstract: A loop antenna has a first antenna generating a first magnetic field and a second antenna generating a second magnetic field such that the first magnetic field and the second magnetic field each have a different axis. A serial resonant circuit and a parallel resonant circuit are provided for the first antenna and the second antenna, respectively. The serial resonant circuit has a ferrite member, a first coil wound around the ferrite member, a resonant capacitor, and a power source connected thereto in series. The in-series connection of the resonant capacitor and the power source are connected across the first coil. The parallel resonant circuit has a link coil wound around the ferrite member, a second coil connected to the link coil in series and wound around a member outside the ferrite member, and a resonant capacitor connected in parallel to the series connection of the second coil and the link coil.

Abstract: An RF antenna includes an input terminal for receiving an RF signal, a supporting element, an electrically conductive coil on the supporting element and disposed to receive the RF signal from the input terminal, and an RF shield formed of an electrically conductive material and disposed under the coil and further including contacts for connection to a ground electrical potential. The antenna generates a circularly polarized RF field. A method of generating an RF field includes generating an RF signal, providing the RF signal to an electrically conductive coil disposed on a magnet core and separated from the magnet core by a supporting element, shielding the electrically conductive coil using an electrically conductive material, and connecting the RF shield to a ground electrical potential so as to provide a current return for the RF signal through the RF shield.

Abstract: A process and a device for the production of a transponder unit (11) comprising a coil (13) and at least one electronic component (23, 24), such as a chip or the like, wherein the component (23, 24) is connected to the coil (13) directly or via a substrate (14), with a plurality of process phases in which the equipping of a winding tool (40) with a substrate (14), winding of the coil (13) in the winding tool (40), and connection of winding wire ends (21, 22) of the coil (13) to terminal surfaces (17, 18) of the substrate in the winding tool (40) take place in such manner that the winding tool (40) serves as operating platform in all of the aforementioned process phases.

Abstract: Communication systems requiring a user to wear a headset or body pack preferably include small aerials that use ferrite cores to achieve transmission efficiency. Driving such aerials typically requires the use of a transformer to obtain the strongest possible magnetic field where only a limited supply voltage is available. The limited supply voltage is addressed by combining a step-up transformer and an aerial array on a single permeable core. The transformer includes a primary winding and a secondary winding that are wound along the circumference of the circular cross-section of a toroidal core. The aerial array includes a transmit winding and a receive winding. The transmit winding is wound along the diameter of the toroidal core and the receive winding is wound along the circumference of the toroidal core. In one embodiment, the receive winding is divided into two matching halves.

Abstract: An improved antenna system for a collar-mounted receiver-stimulator unit of an electronic animal training apparatus includes a conductive antenna mounting connector for detachable connection of an external flex antenna to the receiver-stimulator unit, a ferrite core, and a first winding on the ferrite core is coupled to a receiver circuit of the receiver-stimulator unit, and constitutes an internal ferrite antenna thereof. A second winding on the ferrite core is connected to the antenna mounting conductor and coacts with the first winding to function as a matching transformer between a receiver antenna input terminal and an external high flex antenna connected to the antenna mounting connector. The longitudinal axis of the ferrite core is co-planar with a longitudinal axis of the flex antenna.

Abstract: A novel loop antenna containing a thin-walled ferrite box or other hollow; magnetic core structure of high permeability (considerably greater than 100), particularly useful for crossed loop antennas, and of optimal geometry and configuration for minimum volume, weight and space.

Abstract: A chip antenna in which correct evaluation and inspection of a conductor can be performed regardless of the state of grounding. The chip antenna has a rectangular-prism-shaped substrate formed of a dielectric material comprising, e.g., barium oxide, aluminum oxide and silica. A copper or copper-alloy conductor is spirally wound within the substrate in the longitudinal direction. A feeding terminal for applying a voltage to the conductor and a free terminal are disposed on the surfaces of the conductor. One end of the conductor is attached to the feeding terminal, while the other end is connected to the free terminal.

Abstract: A buoyant loop antenna, deployable along a cable, includes a core region prising a plurality of annular ferrite beads. These annular shaped beads include a center hole and generally concave first end and a generally convex second end. The ferrite beads are aligned with the concave end of one bead against the convex end of another bead. This allows the cable to flex while the beads maintain contact with each other, providing flexibility and resistance to crushing. The core region has a loop wire wrapped helically around it, forming the loop antenna. The loop wire element starts and ends at the same end of the core region, forming a loop. This loop allows transmission and reception in and athwart (side to side) direction. This novel wire loop antenna can be combined with a straight wire antenna (which provides reception in a fore and aft direction) to provide an omni-directional cable antenna assembly.

Abstract: Systems and methods for two dimensional millimeter wave imaging are described. A system includes a spindle assembly defining a rotation axis; a waveguide assembly connected to the spindle assembly, the waveguide assembly including a first dielectric waveguide defining a first axis; and a grating assembly connected to the spindle assembly, the grating assembly including a plurality of sectors, each of the plurality of sectors including a varying period conductive grating pattern. A varying period of the varying period conductive grating pattern is a function of an angle defined by a rotational position of the grating assembly with regard to the rotation axis. The systems and methods provide advantages in that an image can be scanned quickly using an inexpensive system.

Abstract: An antenna includes a transmitter including a first transmit coil wound in a first direction. A second transmit coil is electrically coupled to the first transmitter and wound in a second direction opposite to the first direction.

Abstract: To an oxide magnetic material consisting essentially of, calculated as oxides, 15-30 mol % of Fe.sub.2 O.sub.3, 6-12 mol % of CuO, and 58-79 mol % of NiO as main ingredients, 1.5-4.5% by weight of PbO, 1.0-3.7% by weight of SiO.sub.2, 0.7-1.0% by weight of CoO, and 0.01-1.0% by weight of ZnO are added as additives. The material is suited to form magnetic cores for operation in high-frequency bands.

Abstract: A helical antenna is provided in which a predetermined resonance frequency can be determined at the design stage. The helical antenna includes a conductor which is formed from copper or a copper alloy inside a base in the shape of a rectangular parallelopiped formed from a dielectric material having barium oxide, aluminum oxide and silica as main constituents and which is wound in a helical shape along the length of the base. In such a case, the resonance frequency f0 of the helical antenna and the inductance components L of the conductor satisfy the relationship: ln (L)=A0+A1.times.ln (f0), where ln is a natural logarithm, and A0 and A1 are constants. One end of the conductor is extended onto the surface of the base and forms a power feeding terminal connected to a power feeding terminal formed on the surface of the base for applying a voltage to the conductor, and the other end thereof forms a free end inside the base.