Abstract: A system for ascertaining the range from an interrogator to one or more transponders comprises an interrogator that transmits an RF carrier that is received by each transponder, the energy in the received carrier being used to charge up a storage capacitor in each senses the termination of the received carrier and initiates a known delay interval different from those of the other transponders. At the end of the delay interval, the transponder transmits an RF signal which is received by the interrogator. The interrogator then calculates the range to the transponder by subtracting the known delay interval from the round trip time registered in the timer.

Abstract: Determining the location of wireless devices is improved by storing location information in RFID devices. As RFID devices come within range of each other they examine a confidence level associated with each others location information. The RFID device may update their location information based upon location information received from other RFID devices that have a higher confidence level.

Abstract: An improved system and method for monitoring objects, people, animals, or places uses a passive Modulating Reflector (MR) tag where an antenna is alternately short and open circuited according to a time-varying pattern by a modulating network thereby causing the reflective characteristics of the antenna to vary in accordance with the time-varying pattern. When an interrogator transmits an RF waveform that impinges on the antenna, the return signal reflecting off the antenna is modulated in accordance with the time-varying pattern allowing a remote receiver to demodulate information from the modulated return signal. The MR tag can be used with a wide variety of tag-interrogator configurations employing monostatic and/or bistatic radar techniques to allow monitoring, locating, and/or tracking of objects, people, animals, or place with which MR tags are associated.

Abstract: A wireless, in particular mobile, communication device (8) for communicating with communication units (9) in vehicles (5, 6, 7), comprising a transmitter (26) and a receiver (29) for information-containing electromagnetic waves, as well as a control unit (25) for controlling the transmitter (26), a directional characteristic (10, 10?) being provided for the receiver (29) and/or for the transmitter (26), for a selective communication with communication units (9) in vehicles (5, 6, 7) at distances (D) of more than 10 m, preferably in the order of from 20 m to 200 m, e.g. in the order of approximately 100 m, in particular with a receiving angle, or a radiation angle, respectively, of from 0.5° to 4°, preferably 0.8° to 2.5°, and a sighting unit (13) as well as an indication unit (16, 18) being provided, the indication unit being connected with the receiver (29) via a processing unit.

Abstract: A radio frequency identification transponder includes a power supply and a dynamic memory array that stores data. When power from the power supply ceases, the data in the dynamic memory array is validly maintained for a predetermined period of time. The dynamic memory array is responsive to an interrogating signal for selectively updating the data. A radio frequency identification transponder includes a signal processor that extracts an identifier from the interrogation signal and is responsive to the identifier and the stored data to determine whether some or all of the identifier is stored in the dynamic memory array.

Abstract: Disclosed are systems, methods, devices, and apparatus to interrogate a clothed individual with electromagnetic radiation to determine if a concealed object is being carried. This determination includes establishing data corresponding to an image of the individual with a pair of opposed, semi-cylindrical array panels each configured to interrogate the individual with electromagnetic radiation in the 200 MHz to 1 THz range.

Abstract: A target object detection system for detecting a target object using a detector and a tag on the target object; the tag includes a radio wave receiver receiving radio wave from the detector; a light receiver receiving a light signal from the detector; a receipt signal generator generating a receipt signal; and a transmitter which transmits the receipt signal to the detector; and the detector includes a radio wave transmitter transmitting radio wave to the surrounding area; a receiver receiving the receipt signal from the tag; a light emitter irradiating the light signal to a search region; a controller controlling the radio wave transmitter, the receiver, and the light emitter; and a target position measuring unit measuring a distance to the target object based on the intensity of the receipt signal, and regarding the irradiation direction of the light signal from the light emitter as the direction of the target-object.

Abstract: An attack is activated in a receiver amplifier of an interrogator whenever an amplified input signal exceeds an attack threshold voltage value Vatt, and the receiver amplifier at least during a waiting period, the length of which preferrably equals the double length of the longest time interval between adjacent pulses in a transponder data wave packet, after the end of the attack does not respond in the sense of setting the gain. However, the amplifier responds with a decay activated after the lapse of the waiting period, which started when the instantaneous amplified signal value for the last time after the end of the attack exceeded a waiting threshold voltage level Vw. The decay rate is of the same order of magnitude as the attack rate. The improved method for automatically setting the gain renders it possible that the interrogator receiver within the non-contacting identification system practically does not change the essential characteristics of the input signal.

Abstract: A method and circuit arrangement is provided for load modulation in a receiving oscillator circuit, which can be mutually coupled with a transmitting oscillator circuit, having at least one inductance, at least one capacitance, and at least one controllable impedance. The controllable impedance can have at least one depletion layer element and at least one ohmic resistance.

Abstract: A method for determining the relative position between two or more objects in a marine environment, including waterways, of which at least one object can be maneuvered relative to one or more other objects. At least one interrogator is arranged on one or more of the objects and sends a radio wave signal to at least one transponder arranged on one or more of the other objects. The novel method is the use of a FMCW radar in the interrogator, the use of the transponders for including identity tags into the signals to be reflected to the interrogator, and attitude determination. A system for this determination is also described.

Abstract: A radio-frequency identification (RFID) tag employing a unique reception window and method for operating the tag system provides low-power operation for enhanced tag battery life, while providing addressable tags that can receive commands and data from the system, which can be a wireless local area network (WLAN) incorporating location finding for locating the tags. Interference with other tags and other transmitters is prevented by either using a sniffer circuit to determine that no network transmission is in progress, or by using a special non-interfering coding sequence. A receiver within the tag is operated for a predetermined period of time after a periodic transmission is made from the tag, and an address decoder determines if the tag is being addressed. The receiver can receive data and/or commands after being addressed and is shutdown if the window time elapses, the tag is not addressed, or at the completion of data/command transfer.

Abstract: Cooperative Vehicular Identification Systems and Methods, capable of monitoring and recording vehicular law violations, with the assistance and cooperation of the vehicles in violation, are disclosed. Real-time information from vehicular sensors is communicated to a Central Processing Unit (CPU). Strategically located Interrogator devices, on roads/highways, at intersections, in and around school zones, integrated with traffic lights, etc., issue inquiries/interrogations to passing-by vehicles. Vehicles proximate to such Interrogators respond with unique identifying information and with parameter lists provided by their vehicular sensors. Each Interrogator inquiry can provide data, including the lawful parameter limits (i.e. speed limit) associated with its location. In response to having successfully decoded an inquiry, and in response to the state of its vehicular sensors, a vehicular Transponder may transmit information to the specific Interrogator that has issued an inquiry.

Abstract: To reduce the size, weight and cost of an interrogator which is included in an RFID system and required to have a high output power, the interrogator for transmitting a signal shares a radio wave source or a power supply with a portable wireless terminal such as a mobile phone or a portable communication device. For this purpose, a radio frequency transmitter signal is subjected to amplitude modulation by information to be transmitted to a transponder. Furthermore, part of the radio frequency transmitter signal extracted using a coupler is used to perform synchronous detection on a radio frequency receiver signal returned from the transponder, and data coming from the transponder are extracted.

Abstract: A radio frequency identification (RFID) controller within an RFID system includes an RFID interrogator interface configured to receive signals from an RFID interrogator. The RFID interrogator receives data from RFID tags. The RFID controller also includes a user interface configured to receive a selection of data processing units and an arrangement of data processing units. The RFID controller further includes a controller core configured to process the signals received from the RFID interrogator interface and configured to modify processing of the signals from RFID interrogator based on the selection and the arrangement of the data processing units.

Abstract: In a method for determining the distance between two transmitting and receiving stations, a transmission signal is generated in each station and is transmitted as a series of microwave pulses having a predefined pulse repetition frequency to the other respective station. The coincidence of pulses of the transmission signal sent by the respective station and the signal received by the station is detected in each station as a coincidence event, and the number of pulses transmitted and received by the respective station at the time of the coincidence event is determined. The distance between the stations is then calculated on the basis of the number of the determined pulses.

Abstract: Transponders, receivers and position determining systems are described. In one embodiment, a transponder includes (i) an on-board receiver and associated receiving antenna for receiving incoming radar pulses in a first frequency band at an unknown pulse repetition rate, (ii) means for calculating the pulse repetition rate, (iii) a frequency synthesizer for generating a signal in a second frequency band, (iv) modulation means for modulating the signal generated by the frequency synthesizer so as to encode information into the signal, and (v) a transmitter and associated transmitting antenna for transmitting said modulated signal, wherein the transmitted signal is synchronized with the calculated pulse repetition rate of the incoming radar pulses, and modulation of the transmitted signal is such that accurate positioning of the transponder can be determined at a remote receiver.

Abstract: A system for automatic collection of tolls includes an in-vehicle toll processor having memory for storing a toll-money-available quantity purchased by the user, and a toll-facility-identification site that transmits a toll-facility-identifier signal indicating the identity of the upcoming toll facility. As the vehicle approaches the identification site, the in-vehicle processor receives the identifier signal and calculates the toll to be debited. When the vehicle passes through the toll facility, the in-vehicle processor transmits its identity, its net balance and the toll, which it debits from an account balance. The in-vehicle processor may increment a low balance, in which case it transmits information which is relayed to a central system for billing. Various means for shutting down delinquent in-vehicle components or identifying offender vehicles are described.

Abstract: A system comprises a radar for producing a radar interrogation signal, a transponder for receiving the radar interrogation signal and producing a transponder signal including a first linear frequency modulated pulse having an increasing frequency and a second linear frequency modulated pulse having a decreasing frequency, and a processor for processing the transponder signal to determine a frequency offset between the radar interrogation signal and the transponder signal.

Abstract: A communication apparatus and a communication method prevent responses from being simultaneously received from two or more communicating parties. A first NFC apparatus transmits data for requesting IDs, and acquires IDs sent from second and third NFC apparatuses in reply to the request. After acquiring the IDs of the second and third NFC apparatuses, the first NFC apparatus transmits data that includes their IDs as the data for the second and third NFC apparatuses. If the first NFC apparatus cannot properly acquire the IDs of the second and third NFC apparatuses, then it sends the data for requesting their IDs again. Upon receipt of the request for the IDs, the second and third NFC apparatuses generate their own IDs by using random numbers and send the generated IDs. If the second and third NFC apparatuses receive the request for their IDs again, then they re-generate their own IDs by using random numbers, and send the re-generated IDs again.

Abstract: A radio frequency identification device includes an integrated circuit including a receiver, a transmitter, and a microprocessor. The receiver and transmitter together define an active transponder. The integrated circuit is preferably a monolithic single die integrated circuit including the receiver, the transmitter, and the microprocessor. Because the device includes an active transponder, instead of a transponder which relies on magnetic coupling for power, the device has a much greater range.

Abstract: An interrogator with an antenna that allows information exchanges with multiple transponders in a shorter distance of communication, by securing an intensified and uniform electromagnetic energy concentrated on areas near antenna elements. The interrogator is furnished with a sleeve antenna that includes a monopole conductor of ¼ wavelength (free space wavelength) continuously connected to a core wire of a coaxial cable on one end thereof, and a feed point on the other end, in which the sleeve antenna is grounded at the feed point. The interrogator has a plurality of the transponders arrayed near the antenna, and a plurality of the antennas selected by RF signal selectors. The interrogator antenna allows movable body identification such as in a goods management system for identifying multiply arrayed goods.

Abstract: A radio frequency indentification (RFID) label includes an integrated circuit and an antenna. The label may also include two flexible films directly sealed to each other. The label may be affixed to an article and used in conjunction with an interrogation system to track the article.

Abstract: An RF tag is provided to communicate with an interrogating source in which the tag has programmability and flexibility to uplink data to multiple platforms. As such the RF tag functions as a miniature programmable transceiver capable of communicating with a plurality of different platforms each having different waveform characteristics. With well-controlled spectral characteristics due to stored waveforms and the use of specialized direct digital up and down conversion techniques, data rates up to 256 kbps are achievable. The tag is thus capable of converting microwave signals directly to digital inputs, and the transmitter generates microwave signals directly from digital outputs. Flexible digital processing also allows a throughput of 900 BOPS when using field programmable gate arrays.

Abstract: The present invention comprises a radio frequency identification device that utilizes multiple operating frequencies. In one embodiment of the present invention, one frequency (e.g., an ultra-high frequency such as 915 MHz, 800 MHz, 915 MHz, or microwave frequency such as 2.45 GHz) is used for data transmission, and another frequency (e.g., a low or high frequency such as 13.56 MHz) is used for field penetration. In another embodiment, one frequency is used for reading information received from the multi-frequency identification device, and another frequency is used for writing to the multi-frequency identification device. In an additional embodiment, the multi-frequency identification device utilizes one antenna for all frequencies. In another embodiment, the multi-frequency identification device utilizes two or more antennas for different frequencies, and one common memory. In other embodiments, one or two digital parts, analog parts, antennas, and memories can be used.

Abstract: The present invention provides a system for avoiding code collisions from multiple SAW identification tags and a method of operating such system. In one embodiment the invention provides for (1) focusing an interrogation pulse to within a defined space; and (2) discriminating between coded responses returned from tags located within such defined space.

Abstract: A modulator circuit comprises a negative impedance amplifier which is operable such that a signal applied to the amplifier is reflected and amplified. Switching circuitry is provided for switching the impedance of the amplifier between two reflecting states such that the reflected and amplified signal is phase modulated. The impedances of the negative impedance amplifier are selected such that the phase of the reflected and amplified signal switches by substantially 180°. Preferably, the impedances of the negative impedance amplifier in the two reflecting states are selected such that the reflection gain of the amplifier in the two reflecting states is substantially the same such that the reflected and amplified signal is a binary phase shift keyed.

Abstract: An apparatus for detecting position information of a moving object. The apparatus includes a transponder, a communication module, and a reader. The transponder is installed on a predetermined location of a road and stores position information associated with the installed location. The communication module is mounted to a moving object, emits an RF (Radio Frequency) signal toward a road surface, and receives position information associated with the transponder's installation location from the nearest transponder using an RF signal. The reader receives position information associated with the transponder's installation location from the communication module, and reads a current position of the moving object. The apparatus minimizes a data error between the detected position information. The transponder installed on a road is driven by RF signals received from external devices, resulting in increasing a lifetime of the transponder.

Abstract: The present invention provides a system for avoiding code collisions from multiple SAW identification tags and a method of operating such system. In one embodiment the invention provides for (1) focusing an interrogation pulse to within a defined space; and (2) discriminating between coded responses returned from tags located within such defined space.

Abstract: A far field radio frequency identification (RFID) tagging and tracking system employing a plurality of continuous wave (CW), unmodulated signals selected from frequencies including a predetermined frequency band, includes a RFID interrogator generating a group of CW unmodulated signals corresponding to a RFID tag and receiving a tag identification (ID) signal sequence uniquely identifying the RFID tag, while the RFID tag includes a power source supplying power to the RFID tag but not including a microprocessor. A corresponding RFID tag and method for operating both the tag and the system are also described.

Abstract: An enhanced backscatter RF-ID tag reader system and multiprotocol RF tag reader system is provided. In a multiprotocol mode, the system emits a non-stationary interrogation signal, and decodes a phase modulated backscatter signal by detecting a stronger phase component from quadrature phase representations or determining phase transition edges in a phase of a received signal. The RF tag reader system predicts or follows the phase of the backscatter signal, thereby avoiding interference from nulls in the received signal waveform due to the non-stationary interrogation signal, relative movement or environmental effects. An acoustic RF-ID tag detection system detects the reradiated signal corresponding to respective transformation of a signal in the tag. Detection of either type of RF-ID tags therefore is possible, and the absence of any tag or absence of any valid tag also determined.

Abstract: A data carrier (1) for contactless communication with the communication station comprises firstly a reception stage (3) for receiving an interrogation signal (IS), secondly a generation stage (17) for generating a response signal (RS) upon reception of the interrogation signal (IS), thirdly a processing circuit (18) for processing the response signal (RS) into a transmission signal (MCRS) suitable for transmission to the communication station, fourthly a determination device (22) for determinating at least one representative value (REP1, REP2), the representative value (REP1, REP2) representing the field strength of the field acting on the data carrier (1), and fifthly a control connection (25) between the determination device (22) and the processing circuit (18), wherein the processing circuit (18) is influenced via the control connection (25) in order to vary a transmission parameter of a transmission signal generated by the processing circuit (18) as a function of the at least one representative value (REP

Abstract: An access control system for an object, particularly a motor vehicle, comprises at least one base station with a transceiver device that transmits a wideband modulated interrogation signal, at least one transponder that has a modulation device, in order to modulate an auxiliary carrier signal, the frequency of which is changed between an infinite number of frequency positions, onto an interrogation signal received at a distance from the base station and reflect it as a code-modulated response signal, and an evaluation device that is connected after the transceiver device and that evaluates the response signal in sidebands of the changed frequency positions, with respect code and distance.

Abstract: A system, method and computer program product for positioning pulses, including positioning pulses within a specified time layout according to one or more codes to produce a pulse train having one or more predefined spectral characteristics where a difference in time position between adjacent pulses positioned to produce a spectral characteristic differs from another difference in time position between other adjacent pulses positioned to produce the spectral characteristic. The present invention may include shaping a code spectrum according to a spectral template in order to preserve a pre-defined code characteristic. A pre-defined code characteristic can include desirable correlation, or spectral properties. A transmitter incorporating the present invention can avoid transmitting at a particular frequency. Similarly, a receiver can avoid interference with a signal transmitting at a particular frequency. A radar system, can avoid a radar jammer attempting to jam a particular frequency.

Abstract: A system for providing the identification and tracking of motor vehicles that includes a probe device that transmits a radio frequency modulated signal to a transponder unit that is located within a vehicle registration tag of a vehicle. The transponder unit responds to the probe unit's request by transmitting its own radio frequency modulated signal containing any information requested by the probe device.

Abstract: The vehicle disabling system includes a vehicle control unit for positioning in a vehicle with a transceiver for transmitting and receiving signals to receive an inquiry signal and transmit an identification code upon the receipt of the inquiry signal. A central database station includes memory for storing a plurality of identification codes of vehicle control units. An authorization code is associated each identification code. A mobile law enforcement unit is positionable in a law enforcement vehicle, and includes a transceiver for transmitting and receiving signals to transmit the inquiry signal to a vehicle control unit. The law enforcement unit receives an identification code from the vehicle control unit and transmits the identification code to central database station. The law enforcement unit transmits the stop signal with the authorization code to the vehicle control unit upon receiving the authorization code from the central database station.

Abstract: An harmonic intermodulation article identification system comprises a scanning dipole antenna response to an RF intermodulation harmonic product radiated from RF diodes carried by or embedded in a substrate. The product signature is applied to a spectrum analyzer that outputs a signature identification to a comparator. In response to receiving a signature identification, the comparator scans previously stored signature identifications for a match. A match indicates the received product identification from the analyzer defined a specific substrate such as a document or product tag. A match by the comparator outputs a signal to a display that indicates the identification of a substrate carrying RF diodes generating the compared product identification.

Abstract: A system for visually indicating receipt of a radio communication directed to a user having an associated unique identification code. The system includes a radio transponder having an audio output, means for obtaining and storing the unique identification code; a speech recognition circuit operably connected to the radio transponder audio output and the stored identification code; and a visual indicator operably connected to an output of the speech recognition circuit, such that when the stored identification code and said audio input are substantially the same the visual indicator is driven to activation. A method is similarly disclosed.

Abstract: A radio frequency identification device comprises an integrated circuit including a receiver, a transmitter, and a microprocessor. The receiver and transmitter together define an active transponder. The integrated circuit is preferably a monolithic single die integrated circuit including the receiver, the transmitter, and the microprocessor. Because the device includes an active transponder, instead of a transponder which relies on magnetic coupling for power, the device has a much greater range.

Abstract: A radio frequency identification device comprises an integrated circuit including a receiver, a transmitter, and a microprocessor. The receiver and transmitter together define an active transponder. The integrated circuit is preferably a monolithic single die integrated circuit including the receiver, the transmitter, and the microprocessor. Because the device includes an active transponder, instead of a transponder which relies on magnetic coupling for power, the device has a much greater range.

Abstract: As previously mentioned in the introduction this concept uses components already available and in use, but not being used to achieve this systems goals of providing a safeguard for weapon user/owner their families, and societies. Communications technology combined with firearms to enhance the weapons reliability and improve on its significance as a vital instrument of protection. This modification will bring age-old safety into the information age.

Abstract: A radio frequency identification device comprises an integrated circuit including a receiver, a transmitter, and a microprocessor. The receiver and transmitter together define an active transponder. The integrated circuit is preferably a monolithic single die integrated circuit including the receiver, the transmitter, and the microprocessor. Because the device includes an active transponder, instead of a transponder which relies on magnetic coupling for power, the device has a much greater range.

Abstract: An access control system for an object, particularly a motor vehicle, comprises at least one base station with a transceiver device that transmits a wideband modulated interrogation signal, at least one transponder that has a modulation device, in order to modulate an auxiliary carrier signal, the frequency of which is changed between an infinite number of frequency positions, onto an interrogation signal received at a distance from the base station and reflect it as a code-modulated response signal, and an evaluation device that is connected after the transceiver device and that evaluates the response signal in sidebands of the changed frequency positions, with respect code and distance.

Abstract: A method and system for identifying a plurality of transponders in an interrogation involves transmitting an interrogation signal to the transponders and receiving, at a reader, response signals from the transponders. Each transponder period, and alters the maximum length of the waiting period during the interrogation process.

Abstract: The invention relates to a system for determining a position of a moving transponder adapted to receive a substantially stationary magnetic field signal and to transmit a further signal. The system comprises a signal generating arrangement adapted to generate said stationary magnetic field signal for said transponder, said transponder being adapted to determine a plurality of signal strengths of said received magnetic field signal; at least one signal receiving arrangement, adapted to receive said further signal of said transponder, said transponder being adapted to insert at least one message portion in said further signal indicative of at least one of said plurality of signal received signal strengths and processing means adapted to determine said position in accordance with a plurality of said received signal strengths determined by said moving transponder. This further signal can e.g.

Abstract: A secure cargo transportation system includes a movable container including an enclosure having an opening; a door movable relative to the opening between a closed position, wherein the door restricts access to the enclosure, and an open position; a memory supported by the movable container and configured to store a location coordinate; and an electronic position determining system supported by the movable container and coupled to the memory, and configured to electronically unlock the door in response to determining that the movable container is within a predetermined distance of the location coordinate.

Abstract: A remote control, particularly for a home entertainment system, includes a display screen generating a query regarding the status of the components. The status may include whether the component is on or off or whether media is in a media player. The remote control receives user input indicating the status of the components in response to the query from the remote control. The remote control further includes a transmitter for generating the control signal to the component based upon the indication of the component status from the user.

Abstract: A multi-frequency RFID remote communication system is provided that includes a plurality of RFID tags configured to receive a first signal and to return a second signal, the second signal having a first frequency component and a second frequency component, the second frequency component including data unique to each remote RFID tag. The system further includes a reader configured to transmit an interrogation signal and to receive remote signals from the tags. A first signal processor, preferably a mixer, removes an intermediate frequency component from the received signal, and a second processor, preferably a second mixer, analyzes the IF frequency component to output data that is unique to each remote tag.

Abstract: Disclosed are systems, methods, devices, and apparatus to interrogate a clothed individual with electromagnetic radiation to determine if a concealed object is being carried. This determination includes establishing data corresponding to an image of the individual with a pair of opposed, semi-cylindrical array panels each configured to interrogate the individual with electromagnetic radiation in the 200 MHz to 1 THz range.

Abstract: A radio frequency identification device comprises an integrated circuit including a receiver, a transmitter, and a microprocessor. The receiver and transmitter together define an active transponder. The integrated circuit is preferably a monolithic single die integrated circuit including the receiver, the transmitter, and the microprocessor. Because the device includes an active transponder, instead of a transponder which relies on magnetic coupling for power, the device has a much greater range.

Abstract: A radio frequency identification device comprises an integrated circuit including a receiver, a transmitter, and a microprocessor. The receiver and transmitter together define an active transponder. The integrated circuit is preferably a monolithic single die integrated circuit including the receiver, the transmitter, and the microprocessor. Because the device includes an active transponder, instead of a transponder which relies on magnetic coupling for power, the device has a much greater range.