Abstract: An HF antenna comprising a sheet-like, flexible multipart magnet core (16) manufactured of ferromagnetic material is provided with an antenna winding which is made up of a plurality of turns and surrounds the magnet core (16). The turns of the antenna winding are formed by printed wiring (12a and 12b) arranged on a flexible film (10a and 10b) surrounding the magnet core (16).

Abstract: A system and method which conserves energy in the operation of a transponder or tag (14) by providing that the transponder (14) be enabled or awakened in multiple stages. A threshold detector (62) is provided which measures the power level of received RF energy. If the RF energy received by the detector (62) exceeds a pre-determined level, the transponder (14) then employs a modulation detector (64) to ascertain whether it has been awakened by a valid interrogation signal from an interrogator (12) or whether the RF energy received was merely a spurious burst of RF energy from some other source. If a pre-determined modulation is detected by the modulation detector (64), the transponder (14) is then fully activated to its normal operational state.

Abstract: A method and apparatus with adaptive transponder plucking is provided in which oscillations from a resonant circuit (12 and 14) are maintained by coupling power from a capacitor (18) through a switch (26) to the resonant circuit (12 and 14). The switch (26) is controlled by adaptive pluck circuitry. The adaptive pluck circuitry includes peak level detector (22) and comparator (24). When the peak level of an oscillating signal from the resonant circuit (12 and 14) falls below a reference voltage, the switch (26) is activated to couple power to the resonant circuit (12 and 14).

Abstract: A method of determining the exact location of a transponder with respect to a reader antenna, with no additional components to the existing system required, is disclosed. An existing pin of the reader IC, the RSTP pin, provides an analog fieldstrength signal from which the distance to the reader antenna is deduced via known in the art signal processing methods. A grid or even an exact position location along a route is also achievable with initial set-up of at least two transponders a predetermined distance apart and a reader antenna.

Abstract: A balanced receive antenna circuit configuration determines an accurate position of a transponder within the antenna field pattern of the reader antenna. The balanced receive antenna configuration consists of two antennas physically rotated 90 degrees relative to one another, disposed concentrically on top of one another. Furthermore, each receive antenna consists of two coils located a predetermined distance apart. The optimum distance separating the coils is determined by trading off zero position detection with the transponder detection range. The transmitter antenna surrounds the receiver coilset. In operation, initially the transmitter antenna sends a power burst signal for a predetermined duration to charge up the transponder to the maximum charge possible. Then for a very brief duration, the transmitter antenna is damped to permit the receive antennas to better receive the transponder response telegram.

Abstract: A transponder device (10) includes a discharge circuit (18) to control the discharge of voltage from a charge capacitor (14). The discharge circuit (18) prevents transmission of a data telegram by the transponder device (10) until a voltage of the charge capacitor (14) reaches a threshold voltage level. The threshold voltage level is sufficient to ensure that a complete transmission of the data telegram is performed. Upon reaching the threshold voltage level, a transponder analog and digital circuit (19) initiates transmission of the data telegram. A control logic circuit (32) activates a counter (36) upon the start of the data telegram transmission. The counter (36) generates a control signal that is used to bypass the discharge circuit in order that the charge capacitor (14) can be connected directly to the transponder analog and digital circuit (19).

Abstract: This invention allows a user to have a smartcard (66) and a smartcard-based transponder (14). This smartcard-based transponder (14) can accept money from the smartcard (14). The amount transferred from the smartcard (66) can be stored in the transponder memory (80,82). At a toll plaza (29), a toll amount can be subtracted within a short period of time, so that a vehicle (26) bearing the transponder (14) will not pass through the zone in which the transponder (14) and the interrogator (12) may perform RF communications before an appropriate toll amount can be decremented from the amount stored within the transponder (14).

Abstract: Apparatus and method of identifying a plurality of transponders (10-16) entering into an inquiry field (18) of an interrogation unit (20) are provided. The transponders (10-16) are each assigned a unique identification code. Upon receipt of an interrogation pulse from the interrogation unit (20), each transponder (10-16) responds with its respective identification code. Depending on the spatial distance of each transponder (10-16) with respect to the interrogation unit (20), the interrogation unit (20) detects and receives the strongest response. The received identification code is stored. The interrogation unit (20) repeatedly sends interrogation pulses containing any stored identification code until all of the transponders (10-16) are identified and read.

Abstract: A thin and flat integrated circuit assembly (10, 40) may be achieved by using a thin carrier (20) with shallow cavities (22, 24) for holding the integrated circuits (16) and/or discrete circuit components (14). The integrated circuits (16) and/or circuit components (14) may be friction fitted in the cavities (22, 24) or they may be secured therein by the use of adhesives and/or solder. Electrical connection between the integrated circuits (16) and circuit components (14) may be done with wire bonding, ribbon bonding, tape-automated bonding, lead frames, flip chip bonding, and/or conductive gluing of leads. The circuit assembly may then be accommodated into a credit card-sized packaging with standard dimensions set by the International Standards Organization.

Abstract: A balanced receive antenna circuit configuration determines an accurate position of a transponder within the antenna field pattern of the reader antenna. The balanced receive antenna configuration consists of two antennas physically rotated 90 degrees relative to one another, disposed concentrically on top of one another. Furthermore, each receive antenna consists of two coils located a predetermined distance apart. The optimum distance separating the coils is determined by trading off zero position detection with the transponder detection range. A third receive reference antenna is concentrically disposed, sharing the same horizontal plane with the balanced antenna coilsets. The transmitter antenna is disposed separately from the receive antennas. In operation, initially the transmitter antenna sends a power burst signal for a predetermined duration to charge up the transponder to the maximum charge possible.

Abstract: A method and apparatus for wireless supplying of chemicals is provided in which an interrogation unit (14) transmits interrogation signals. A responder unit (16), powered from the interrogation signals, is operable to receive the interrogation signals and transmit responses. The responder unit (16) controls operation of an actuator (10). The actuator is coupled to a supply tank (12), which supplies chemicals under control of the actuator (10).

Abstract: An arrangement for monitoring the operating state of vehicle pneumatic tires (14) mounted on wheel rims (10) is provided with sensors (40, 42) for detecting the air pressure and the air temperature in each tire. Furthermore, it includes transmitting means comprising rim-side mounted rotor members (28) and bodywork-side mounted stator members (32) coupled thereto for transmitting the parameters detected by the sensor (40, 42) to an evaluating arrangement in the vehicle connected to the stator members. The pressure sensor (40) and the temperature sensor (42) of each tire (14) are coupled to a first transponder (44) which as reaction to an interrogation signal generated by the evaluating arrangement transmits the data supplied to it by the pressure sensor (40) and the temperature sensor (42) to the rotor members (28) of the transmitting means.

Abstract: An alternative resonant circuit configuration reduces the amount of RF current that is switched by the power-stage transistors of a T/R unit and thereby also significantly reduces the reliability risk. A parallel resonant antenna configuration of coils and capacitors reduces the RF current through the output stage push-pull transistor configuration to a small fraction of the RF current experienced by typical series resonant circuits. This circuit offers advantages of low cost, reliable impedance matching while reducing the volume necessary to perform the function.

Abstract: A transponder system comprises an interrogation unit for communicating with a plurality of responder units. At least one responder unit receives an interrogation signal from the interrogation unit and returns data as signal information to the interrogation unit in response to the reception of the interrogation signal. The responder unit also includes sensor circuitry sensitive to predetermined physical parameters in the environmental area of the responder unit and, via a data processor, generates data representative of the physical parameter and sends it back to the interrogator as signal information.

Abstract: An object of the invention is to provide a reader which can read transponders having different communication standard protocols with a minimum loss of demodulation speed performance and with the least amount of additional components.

Abstract: A hardware and software solution for providing a tamper-proof, batteryless, remote transponder which will only be programmable by an authorized user is disclosed. This goal is achieved through the use of a hardware Cyclic Redundancy Check (CRC) generator which checks during a WRITE function of the data that is received from the Reading/Writing (R/W) unit and also generates several protection bits (Block Check Character; BCC) which are sent back during the response function (READ). Before the CRC generator checks the data during a WRITE function, however, it must be set to a predetermined start value called a Segment Code, and the Segment Code of the R/W unit must be the same as the Segment Code of the transponder in order for a Write (or a READ) to be performed. Additionally, programming of the Selective Address must be done within a predetermined time window (has a predetermined Time Code).

Abstract: This invention describes a multi-deposition system, whereby directing elemental or molecular source fluxes across a substrate in an asymmetrical manner and rotating the substrate at low rotation speeds, a superlattice is formed having a composition of A(x-.DELTA.x)B(1-(x-.DELTA.x))/A(x+.DELTA.x)B(1-(x+.DELTA.x) where .DELTA.x is a function of the nonuniform focusing of the elemental or molecular source fluxes A and B. More specifically, superlattices 18 are formed in the ternary and quaternary In(GaAl)As alloys on InP by molecular beam epitaxy without mechanical shuttering. The superlattice 18 is formed by nonuniformly directing the group III elements 22 and 24 onto the substrate 26 and rotating the substrate 26 across the beams. Periodic ordering is produced by rotation of the substrate 26 through a nonuniform distribution of source fluxes at the rotating substrate 26. The growth rate and substrate rotation rate together determine the superlattice period.

Abstract: An antenna comprising a sheet-like, flexible multipart magnetic core (16) manufactured of ferromagnetic material is provided with an antenna winding which is made up of a plurality of turns and surrounds the magnet core (16). The turns of the antenna winding are formed by printed wiring (12a and 12b) arranged on a flexible film (10a and 10b) surrounding the magnet core (16).

Abstract: An antenna circuit to be used in conjunction with a chip transponder such that the antenna circuit serves for both the reception of interrogative signals intended for the transponder as well as for response signals that ape to be transmitted by the transponder. The antenna circuit has at least one magnetic circuit of high .mu. material, and is formed of ceramic core means, that have been built into a depression in a thick-walled surface intended to receive the chip transponder. This thick-walled surface may be of metal. The ceramic core means comprise at least a ceramic core resonator and half a ceramic core that functions as an antenna with its open side facing outward. In one aspect, the ceramic core resonator and the half ceramic core antenna are coupled by means of one or more secondary coils of the closed ceramic core, which also form the coils of the half ceramic core antenna. In another aspect, the secondary coil forms a resonating circuit with at least one capacitive element in series.

Abstract: Injector (1), comprising a housing to which is fixed a hollow needle (17) provided with conveyance means (3,4) for moving an object such as a transponder (22) through said needle (17). Such transponders (22) are inserted in living beings for identification purposes. Metering means (11,12) are provided in the injector (1)in order to permit the introduction of a fluid such as a disinfectant during the insertion of such objects (22). Such means comprise a storage place for fluid (11) which is connected to channel means (8) which open into the movement path of the object (22). In this way fluid is added during the positioning of the object (22).