Abstract: The invention relates to a device for low-frequency communication by magnetic coupling of the type comprising a magnetic field emitter and a receiver placed in an identification member, one of either the emitter or the receiver being furnished with a loop antenna, in which the other of either the emitter or the receiver is constituted by the association of three coils (1, 2, 3) wound around three perpendicular axes (Ox, Oy, Oz) defining a trihedral so as to obtain an omnidirectional magnetic field by supplying said coils with currents of like frequency.

Abstract: A planar antenna including a rectangular conductive element formed from two square elements. The square elements are defined within the rectangle by a centrally located and bifurcated return conductor having two legs. Each square element is connected at one end to a connector element and at the other end to the return conductor. The dimensions of the square elements are chosen so as to maximize gain for selected radio frequencies. The antenna further includes one or more additional but partial square elements, each additional partial square element terminating adjacent the respective square element at one end and being defined by one leg of the return conductor on one side.

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 series of antennas with a three-dimensional structure based on the folding back onto themselves of planar multi-loop arrays of more than two elements is provided. In this way, more compact antennas are provided, with improved broadband design capabilities and wider bandwidths, both in impedance and gain. A three-dimensional antenna array comprises a plurality of rectangular full-wave loops arranged in a three-dimensional array, comprising a plurality of radiators, each radiator having two ends, and a plurality of transmission lines, each transmission line connecting a pair of the radiators through a corresponding end of each connected radiator, wherein each of the plurality of radiators is fed from a common feedpoint substantially at a geometric center of the three-dimensional antenna array.

Abstract: An antenna array comprises a plurality of antenna loops disposed to define a portal or passageway or other detection region in which the plural antenna loops transmit and/or receive electromagnetic signals. A processor coupled to the plural antenna loops processes at least the received signals and/or transmitted signals. The plural antennas may be arrayed in a rectangular array, on hanging flexible substrates or other suitable arrangement, and may be coupled to the processor by a filter or selective switch. The processor may be coupled to a utilization system for cooperating therewith for performing a desired function.

Abstract: An antenna arrangement with an earth plate with a plurality of radiators which are arranged in parallel to the earth plate at a distance therefrom, where the radiators for covering a given frequency range have a similar length and are adjacent and parallel to one another, a first terminal of each radiator is arranged in the region of the respective one end of each radiator and is connected to the earth plate via a first connection, the said first connections are closely adjacent to one another or coincide, and a second terminal for a feed line is provided on reach radiator at a distance from its first terminal, wherein the radiator has the form of a flat loop comprising two closely adjacent, long conductors which are connected at adjacent ends by a short conductor, and the second terminals are provided in the region of the respective other end of each radiator, and that the total length of each individual radiator corresponds approximately to ½ wavelength in the given frequency range.

Abstract: A device for generating a plasma includes an enclosed chamber and an antenna positioned adjacent the wall of the chamber. A ceramic shield is mounted on the wall, with the antenna located between the wall and the ceramic shield. There is also a barrier that is mounted on the wall with the ceramic shield being between the barrier and the antenna element. An alternating voltage source is provided to energize the antenna element to generate a plasma in the chamber. In operation, the ceramic shield isolates the antenna from the plasma in the chamber, and the barrier prevents the deposition of material components from the plasma on the ceramic shield.

Abstract: An antenna system includes a first portion and a second portion. The first portion and the second portion form an antenna loop. The first portion may be etched on a printed circuit board. The second portion may be coupled with the first portion or extend from the first portion. The first portion and the second portion each may have one or more turns. Further, the second portion of the antenna loop resides in a three-dimensional geometric space that is different from the first portion of the antenna loop. The antenna system is particularly well suited for electronic devices having a confined internal space, for example, a cordless pointing device, a cordless gaining device, or a cordless camera device. A method for designing an antenna system is also disclosed.

Abstract: The present invention is directed to a method and an identification element (8) comprising an integrated circuit and an antenna coil disposed on a substrate. With respect to the identification element, it is proposed that the conducting track/conducting tracks of the antenna coil be die-stamped from an aluminum foil, that terminal pads referred to as bumps projecting from the undersurface of the integrated circuit be formed on the contacts of the integrated circuit, and that at least in the area of the bumps provision is made for a substance which, as a result of a defined volume reduction occurring during curing, produces a compressive and/or tensile force between the integrated circuit and the substrate so that the bumps are connected to the antenna coil by a press contact.

Abstract: Supporting conductors for loop antennas that are positioned within the principal H plane of the loop antennas and positioned diagonally with respect to the plane of the loops.

Abstract: An apparatus for inductively coupling a nuclear magnetic resonance signal into a reception antenna has three resonant coil arrangements that are decoupled from one another and which have respective imaging areas oriented perpendicularly to one another and at least partially overlapping. A medical intervention instrument carries such an apparatus for inductive coupling arranged at its invasive section.

Abstract: An antenna adapted to apply a uniform electromagnetic field with high energy density to a volume of gas. The antenna includes an input node for receiving electrical energy and a first coil for radiating electromagnetic energy into the gas. The first coil is connected to the input node on one end thereof and is grounded on the opposite side to cause flux to flow in a first direction. A second coil is included for radiating electromagnetic energy into the gas. The second coil is also connected to the input node on one end thereof and grounded on the opposite side to flow in the first direction. Multiple number of coils can be added to form an antenna. In an illustrative application, the antenna is used in a plasma processing system comprising a vacuum chamber, a gas disposed within the vacuum chamber, and a dielectric disposed around the vacuum chamber. The inventive antenna is mounted around the dielectric tube and radiates electromagnetic energy into the gas.

Abstract: A loop antenna which is electrically small relative to a wavelength of a signal which it is designed to receive. The antenna is an electrically small, low profile, band switchable antenna which can be mounted on a metallic surface such as a truck or railway car rooftop and can be used to communicate with earth satellites. The antenna is polarized such that the plane containing the electric field is horizontal. Alternatively, the antenna can receive circularly polarized signals.

Abstract: A loop antenna device 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 series resonant circuit and a parallel resonant circuit are provided for the first antenna and the second antenna, respectively. The series resonant circuit has at least a second coil, a link coil wound around a ferrite core, and a capacitor in series. The parallel resonant circuit has a first coil and a capacitor. When one of the first and second antennas are disposed in the vicinity of a conductor, an electromagnetic wave absorbing member is disposed between a conductor and one of the first and second antennas.

Abstract: An antenna arrangement, which is preferably incorporated in a transponder reader, comprises a first subloop, which essentially encloses a first area and which has a first and a second end, a second subloop, which essentially encloses a second area and which has a first and a second end, the two first ends of the first and the second subloop being connected together and the two second ends being connected together in such a way that the two subloops together constitute a single winding, and a single feeding device for applying a voltage between the connected first ends and the connected second ends, the first and the second subloop being so positioned relative to each other that the first and the second area are so arranged facing each other that plane areas approximating to the areas are parallel to each other or intersect one another at an acute angle.

Abstract: An antenna element is disclosed that is a pair of approximately coplanar loops, having perimeters of approximately one wavelength, that are connected at one point. The loops are positioned so that a line through center of one loop and that common point also is the line through the center of the other loop. The approximate shape of these loops is such that the distance from that common point to any point on either loop is proportional to the cosine, raised to some power, of a multiple of the angle between that center line and a line between the common point and the point on the loop. Compared to previous antenna elements constructed for the same purposes, antennas constructed with such loops can yield more directivity, particularly in the principal H plane, without producing large minor lobes of radiation. Several applications of such antenna elements in various arrays also are disclosed.

Abstract: A planar antenna including a rectangular conductive element formed from two square elements. The square elements are defined within the rectangle by a centrally located return conductor. Each square element is connected at one end to a connector element, and at the other end to the return conductor. The dimensions of the square elements are chosen so as to maximize gain for selected radio frequencies. The invention further includes a method for providing conductive elements on a substrate, including the steps of printing a conductor pattern onto a substrate using conductive ink; and electrodeposition further conductive material onto the conductor pattern, using the pattern formed from conductive ink as an electrode in an electroplating process.

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: An antenna connector has a wrist-band contact part for attachment to a wrist-band and connection to an antenna therein and for rotatable arrangement on a wrist-watch pin, and a wrist-watch contact part for rotatable arrangement on the wrist-watch pin in electric contact with the wrist-band contact part and for connection to electronic means within a wrist-watch.

Abstract: The present invention presents an antenna device for an automotive vehicle wherein a first coil is installed horizontally to receive radio signals. Capacitors are connected electrically and in parallel with the first coil. A second coil is connected electrically with the first coil and installed horizontally under the first coil. A third coil is connected electrically between the first coil and the ground and installed horizontally under the first coil. Additionally, a fourth coil is connected electrically between the first coil and the second coil and installed vertically under the first coil. This antenna device, now including the first to the fourth coils and capacitors, is installed in a mirror case for the car.

Abstract: A portable radio communication device, comprising: a housing (78); antenna means for transmitting and receiving RF signals; transmitting and receiving circuits arranged in the housing; at least a conductive portion; antenna feeding means; and, a user interface. The antenna means includes a transmitting antenna (60, 61), and a receiving antenna (60, 61, 65, 78). The transmitting antenna, and the receiving antenna have orthogonal radiating characteristics in relation to each other. The transmitting and the receiving antennas can be of an electric dipole type or a magnetic dipole type. An antenna system including a transmitting and a receiving antenna is also disclosed.

Abstract: High frequency (HF) antennas for wideband signals are used in the tracking of railcars. These are rugged antennas especially adapted to the hostile environment of a railcar. One antenna is in the form of a magnetic loop. Another generates an electric field produced by a plate mounted just below the railcar undercarriage with an optional dielectric slab situated between the plate and the undercarriage. The antennas need not be specified in terms of optimal parameters since the approach taken is to provide a generic antenna structure adapted to being fitted underneath the carriage of a railcar. This generic structure exhibits a mitigated Q and is capable of broadband tuning. This feature makes the antenna easier and less costly to produce in large quantities and facilitates use of a standard fitting mechanism and installation procedure.

Abstract: A rotating field antenna is provided which includes a figure eight shape loop, a center loop magnetically coupled to the figure eight shape loop, and a drive element for driving the figure eight loop. The figure eight shape loop has an upper loop, a lower loop and a crossover region therebetween. The center loop overlaps at least a portion of the crossover region and at least a portion of one or both of the upper and lower loops. The center loop has no direct or physical electrical connection to the offset figure eight shape loop. Magnetic induction produces a 90-degree phase difference between the phase of the figure eight loop and the phase of the center loop. The antenna thereby produces a rotating composite field when driven by the drive element. The figure eight loop and the center loop are coplanar. The drive element may be an amplified voltage source which has a fundamental frequency of about 13.

Abstract: In one aspect, the invention encompasses a system for electronic identification of a plurality of units. The system comprises transponders which are connected with respective individual units, and which comprise antennas. The system further comprises an interrogator configured to read the transponders. The interrogator includes an interrogator antenna. At least one of the interrogator antenna or the transponder antennas comprise a coil of conductive material which has a first planar portion within a first plane and a second planar portion within a second plane, with the first and second planes intersecting. In another aspect, the invention comprises a method for electronic identification of a plurality of passing animal bodies, wherein the individual animal bodies have respective transponders associated therewith. An interrogator having an antenna associated therewith is provided.

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: Low impedance loop antennas utilize a loop separated into a plurality of radiating segments fed in parallel. A four point feed loop antenna, including radiating segments 12, 13, 14, 15 had a measured input impedance varying from 1.8 to 5.8 Ohms over a range of 5 to 15 MHz, without excessive radiation Q degradation. An incorporated feed network includes transmission line segments, with conductors on opposite surfaces of a thin substrate, connecting the radiating segments to a centrally mounted coaxial connector for parallel excitation. Operating bandwidth of the loop antenna is determined by the characteristic impedance of the transmission line feed segments. Low impedance loop antennas which are small relative to operating wavelength can be fabricated on a thin flexible substrate for field transport and use. Incorporation of the antenna into a jacket or other clothing enables field use while minimizing restriction of activity of the user.

Abstract: In antenna device which is to be used in a portable radio receiver, plural loop antennas 1 and 3 which are formed along different faces of a case 9 of the radio receiver, respectively, and switching means 5 for selecting one of received signals from the plural loop antennas are disposed. Reception is performed while selecting a loop antenna having a higher received signal level. When an antenna having the directivity or the plane of polarization which are more advantageous is selected, it is possible to ensure high reception performance.

Abstract: A key and lock system has a key with an integrated transponder coil that is connected to a transponder unit, and a lock with an integrated write/read coil. The key has a key bit portion and a bow portion. When the key bit portion is inserted into an elongated aperture of a key cylinder of the lock, an axis of the write/read coil forms an acute angle with an axis of the transponder coil. The acute angle substantially differs from a zero degree angle.

Abstract: In an antenna 1a for reader/writer of an interrogator in a non-contact data carrier system comprising the interrogator and a transponder, the antenna for reader/writer of the interrogator comprises a transmitting antenna 2 for transmitting a signal to the transponder and a receiving antenna 3 for receiving a signal from the transponder, and the receiving antenna 3 is a loop coil located at a position where magnetic fields of opposite polarities are induced in the receiving antenna 3 by magnetic coupling between the receiving antenna 3 and the transmitting antenna 2 and where the magnetic fields of opposite polarities cancel out each other. Preferably, the transmitting antenna 2 is comprised of at least two loop coils 2a, 2b for generating magnetic fields of opposite polarities to each other.

Abstract: A wireless communication system automatically aligns a magnetic induction field to establish a two-way communication link between a stationary base unit located, for example, at a user's work station, and a remote unit worn by the user, for example, as a headset or body pack. At any point in time, the base unit and the remote unit have an arbitrary relative orientation to each other. The base unit senses this orientation, then aligns the magnetic induction field to maintain the communication link with the remote unit. In one embodiment, the base unit preferably includes an aerial array having a number of mutually orthogonal windings. Each winding produces a signal when a magnetic induction field generated by the remote unit passes through the base unit. A selector module selects the longitudinal axis of the winding with the strongest signal as an approximation of a direction vector defining the orientation of the magnetic induction field relative to the base unit.

Abstract: An antenna comprises a plurality of small diameter conductive wires disposed in a dielectric tube. The number and dimensions of the conductive wires is selected to improve the RF resistance of the antenna while also facilitating a reduction in thermal gradients that may create thermal stresses on the dielectric tube. The antenna may be mounted in a vacuum system using a low-stress antenna assembly that cushions and protects the dielectric tube from shock and mechanical vibration while also permitting convenient electrical and coolant connections to the antenna.

Abstract: A single antenna transmits and receives signals. The single antenna has first and second antenna loops substantially lying in a common plane and partially overlapping. First and second transceiver circuits are coupled to the first and second antenna loops respectively, for respectively generating in a first mode of operation first and second pulsed magnetic fields together defining an interrogation zone for a marker generating a characteristic response to the magnetic fields in the interrogation zone, and for receiving signals from the interrogation zone in a second mode of operation. The first and second transceiver circuits alternately generate the first and second magnetic fields substantially in phase with one another and substantially out of phase with one another. The partially overlapping antenna loops prevent detuning of the transceivers otherwise resulting from the phase alternating.

Abstract: A local television antenna system for use with a satellite television system includes an omnidirectional antenna, a support structure for mounting the omnidirectional antenna to a satellite television dish support, and receiving circuitry mounted to the omnidirectional antenna. The omnidirectional antenna includes an antenna plate, having electrical circuit paths formed thereon, and first and second antennas having curled ends. The support structure includes a integrally-molded double clamp for providing a mechanically strong coupling to the satellite television dish support and first and second brackets for mounting to the omnidirectional antenna to provide a mechanically strong coupling. The receiving circuitry is shielded to limit interference and includes filter and amplification circuitry and one or more diplexers for combining a received local television signal with a received satellite television signal.

Abstract: An electrode having a contact surface with the electrolyte consisting of a number of carbon fibers (1), and a method for the manufacture of an electrode where a number of carbon fibers (1) are wound into a carbon fiber skein (2) whereupon the skein (2) is gathered together at a connection area and embedded to form a connecting stud (5), which is then treated so that the end surfaces (6) appear of all the carbon fibers gathered together in the connecting stud (5), after which the carbon fiber end surfaces (6) are connected to a signal conductor (8). And an antenna (12) comprising electrically connected electrodes where the contact surface of each electrode with the electrolyte consists of a number of carbon fibers (1).

Abstract: A passive electrical marker has tuned circuits, each of which includes a coil and a capacitance. The tuned circuits are oriented with respect to each other in a predetermined arrangement so as to provide a broader spatial response. A foamed core inside of the tuned circuits maintains the tuned circuits in their respective orientations and protects the tuned circuits from mechanical shock. A shell or housing around the foamed tuned circuits provides environmental protection to the tuned circuits. The tuned circuits can be foamed together in a mold and then placed into the housing. Alternatively, the tuned circuits can be foamed together inside of a housing, which housing maintains the orientations between the tuned circuits during foaming. As still another alternative, the housing can be applied to the outside of the foamed tuned circuits as a coating.

Abstract: An antenna array for detecting a coded radio frequency identification (RFID) tag signal generated by a tag during passage of the tag through a detection volume, or portal. The array comprises at least first and second antennas disposed at different positions around the periphery of the detection volume, and circuitry, having inputs connected to receive the respective output signals from the first and second antennas and an output connected to a signal receiver for decoding the detected signal. The circuitry provides an output signal including the respective output signals of the first and second antennas, and the sum of the output signals of the first and second antennas. Preferably, the output signal of the circuitry additionally includes the inverse of the output signal of the second antenna, and the sum of the output signal of the first antenna and the inverse of the output signal of the second antenna.

Abstract: A continuous method of fabricating multiple band antennas having first and second conductive wire lengths that are partially overlapped a selected distance, at least one of the wire lengths being insulated, includes the steps of: severing a first end of at least one of the wire lengths from a second end of a preceding antenna; defining an overlap portion of the first conductive wire length coextending a selected distance along and adjacent an overlap portion of the second conductive wire length, defining an overlap; and severing the second end of at least one of the wire lengths from a first end of another of the one of the wire lengths after the overlap is defined. At least one of the conductive wire lengths is insulated. The overlap portions of the conductive wire lengths and the insulation therebetween comprise and define a mechanical and a reactive coupling.

Abstract: In an electronic article surveillance system, quadrature transmitting and receiving antennas are used to improve field distribution. A transmitting antenna arrangement includes first and second adjacent co-planar antenna loops and excitation circuitry for generating respective alternating currents in the first and second loops such that the respective alternating currents are 90.degree. out of phase. In a receiving arrangement, respective signals received from two adjacent co-planar antenna loops are respectively phase-shifted by +45.degree. and -45.degree., and the resulting phase-shifted signals are summed. A far-field cancelling transmitting antenna arrangement includes four loops operated at phases of 0.degree., 90.degree., 180.degree. and 270.degree. respectively. All four loops may be co-planar, with any bucking vertical segments being horizontally displaced from each other. Alternatively, the 0.degree. and 180.degree.

Abstract: A multi-directional RFID read/write antenna unit is described which provides multi-directional RF communication to a source, such as a RF tag. The antenna comprises a plurality of coils adapted to transmit multi-directional RF signals to a RF tag and receive RF response signals from the RF tag. The RF antenna includes a switch for selecting at least one of the RF antenna coils for transmission of the RF signals and receipt of the RF response signals whereby the RF signals can be directed toward and received from a plurality of different directions from a fixed position.

Abstract: A top-loaded, vertically polarized antenna (10) comprised of two ring radiators (108, 110) formed into loops to provide a dual resonant frequency antenna less than 8 inches on a side for use in the 130 to 150 MHz frequency band. By using separate transmit and receive elements, separate resonant frequencies can be provided without the use of lossy duplexers. The antenna can be concealed inside a housing also containing the radio equipment.

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: A plurality of antennas are disposed in a predetermined area and wherein size, configuration and mounting condition of the antennas are set so that their directivities formed by interference therebetween are most desirable.

Abstract: A multiple loop antenna of a radio paging receiver comprising a first loop antenna, and a second loop antenna electrically connected to the first loop antenna, wherein the second loop antenna is positioned with respect to the first loop antenna to receive a radio wave travelling in a direction in which the receiving sensitivity of the first loop antenna is lowered.

Abstract: An antenna arrangement includes a passageway having at least one side and an antenna located in a substantially vertical plane of the side. The antenna has one or more coils, each having a corner and adjacent straight portions oriented at an acute angle to a floor surface of the passageway. The acute angle is preferably 30.degree. to floor surface.

Abstract: A Radio Frequency Identification (RFID) security tag for attachment to a small article of merchandise to monitor the tagged item. The security tag uses a thin flexible strip. An RFID tag device is coupled to the thin flexible strip and is used for storing data related to the small article of merchandise to be monitored. A plurality of conductors are laid on the thin flexible strip. The plurality of conductors are coupled together to form a multiple turn coil for providing energy to the RFID tag device when a first end of the thin flexible strip is coupled to a second end of the thin flexible strip to form a loop.

Abstract: An antenna system is described having a plurality of elements, one of which is an active element for transmitting or receiving signal, the remaining lements acting as reflectors, and wherein the elements may be comprised of a series of diodes connected in series with conductors having a length that is a fraction of the wavelength of the design frequency. When its diodes are biased for conduction, an element can radiate or receive r.f. signals or act as a reflector, and when its diodes are not conducting, the element is transparent to r.f. of the design frequency.

Abstract: A radio antenna system comprises a single low impedance feed socket coupled to a junction point splitting the feeder power into two separate circuits each of which passes approximately half the feed input power around a respective one of two conductors insulated from each other and in close proximity over their lengths and forming a dual loop not more than ten per cent of the operating wavelength in circumference at the lowest frequency to be radiated, the power flowing in opposite directions around each loop and having approximately plus and minus 45 degrees electrical phase difference produced by two series capacitors, the one being ahead of the first conductor, and the other being after the second conductor, the said conductors of the loop being in sufficiently close proximity to provide interaction of the fields through Poynting vector synthesis.

Abstract: This invention relates to an antenna for use in detecting electromagnetic noise radiation in which a high frequency, asymmetric signal has been generated. The invention relates to a loop antenna design which uses two loops that are run in opposite direction to each other, thereby resulting in two out-of-phase signals being detected in the loops which are then combined as the antenna output.

Abstract: An inductively coupled plasma reactor for processing a substrate has an inductively coupled coil antenna including plural inductive antenna loops which are electrically separated from one another and independently connected to separately controllable plasma source RF power supplies. The RF power level in each independent antenna loop is separately programmed and instantly changeable to provide a perfectly uniform plasma ion density distribution across the entire substrate surface under a large range of plasma processing conditions, such as different process gases or gas mixtures. In a preferred embodiment, there are as many separately controllable RF power supplies as there are independent antenna loops, and all the separately controllable power supplies receive their RF power from a commonly shared RF generator.

Abstract: Antenna system including a first antenna which is connected to a first transmit and/or receive unit and which has a natural frequency of at least approximately the value fm. The system also includes a second antenna which is linked both inductively and mechanically to the first antenna and which has a natural frequency of at least approximately the value fm. The first and second antennae are designed to be linked to another antenna system with at least a third antenna which has a natural frequency of at least approximately the value fm and which is connected to a second transmit and/or receive unit intended for the transmission of data to and/or reception of data from the first transmit and/or receive unit. At least one transmit and/or receive unit, either of the first or the second transmit and/or receive unit, is located at a route point on a public thoroughfare. The other transmit and/or receive unit is located on a vehicle driving on the public thoroughfare.