Abstract: An EAS tag polling system includes a plurality of EAS tags and a base station, wherein each of the tags transmits an acknowledgement to the base station. The base acknowledgments may be sent passively or actively in response to a request from the base station. The base station discriminates between each acknowledgment received and associates it to the tag from which it had been transmitted. From each acknowledgement received, the base station indicates that a positive response is associated with each of the tags from which the acknowledgement is received and a negative response is associated with each of the tags from which the acknowledgement is not received.

Abstract: Methods and apparatus for assigning a pseudo address to an aircraft not equipped with an ADS-B transponder and maintaining the assigned pseudo address over a number of regions each supported by different TIS-B systems. In an exemplary embodiment, each TIS-B system is assigned a range of addresses particular to the region in which the TIS-B system is located.

Abstract: An apparatus for an enhanced receiver for an RFID Tag Interrogator is described. The enhanced receiver has a zero crossing detector, a phase shifter, a pulse generator and a chopper. The zero crossing detector produces a sampling signal from the current transformer. The phase shifter modifies the sampling signal by producing a 90 degree phase shifted sampling signal. The pulse generator increases time duration of each pulse of the phase shifted sampling signal, which is then fed to the chopper. Thus, the chopper samples the backscattered carrier signal every 90 degree phase shift from the time when the backscattered carrier signal passes the zero crossing. This makes isolation of the backscattered signal from the carrier signal more effective.

Abstract: An active device includes a receiving antenna (6) that receives an electromagnetic (2) signal coming from a localisation system (3) and at least one emitting antenna (8) that 5 resends said signal (2) to said localisation system (3), and is characterised in that said device (4) includes a plurality of said emitting antennae (8) connected to at least one receiving antenna (6) in such a way that said emitting antennae (8) receive the electromagnetic (2) signal coming 10 from said at least one receiving antenna (6), with each of said emitting antennae (8) being the ones that resend the signal (2) to said localisation system (3). This offers the possibility of creating artificial measuring points that are retained over time easily, cheaply and simply, 15 whether in wooded zones, snow-covered zones or at sea.

Abstract: A timing circuit that can function as an accurate persistent node in an RFID tag includes a power capture circuit for capturing power from a power source, and a counter circuit that provides a count representing a progression of time. The count can then be compared to a reference value representing a time constant of the circuit.

Abstract: A device for determining the bearing of a vehicle using Inertial Reference Unit (IRU) and Traffic Alert Collision Avoidance System (TCAS) data. The device includes a means to communicate with the vehicle such as a transmitter, receiver, and antenna. The device also includes a processor configured to receive the IRU and TCAS data from the vehicle via the communication means and then generate a bearing value using the received data.

Abstract: A method for performing operations and for improving production in a well includes the steps of: providing radio identification devices at known locations in the well, and providing a reader device configured to read the identification devices, and to control the operations responsive to signals from the identification devices. The method also includes the steps of providing a process tool, and transporting the process tool and the reader device through the well. The reader device is programmed to control the process tool upon reception of a response signal from a selected identification device. The method can be used to perform perforating processes, packer setting processes, bridge plug setting processes, logging processes, inspection processes, chemical treating processes, and cleaning processes. In addition, the method can be performed dynamically by controlling the tool as it moves through the well, or statically by stopping the tool at a particular location within the well.

Abstract: The present invention describes a system and method of OAM diverse signal processing using classical beams for applications in which OAM signal character is controlled such as optical tagging and applications in which OAM signal character is not controlled such as clutter mitigation and interference cancellation for target detection, identification etc. This is accomplished by transmitting a source beam having a prescribed state with one or more non-zero OAM components, reflecting the beam off a ‘tagged’ or ‘untagged’ target and receiving the return beam in the direct return path to measure the one or more OAM components to identify the target. OAM processing provides additional degrees of processing freedom to greatly enhance the processing capabilities to detect and identify both ‘tagged’ and ‘untagged’ targets.

Abstract: A series of radio frequency identification (RFID) systems are delineated. An RFID system comprises an RFID signpost having a transmitter for transmitting signals of a predefined type, and a receiver for receiving signals of the predefined type, wherein the transmitter for transmitting signals of the predefined type cannot transmit until a determination is made that the predefined type of signal is not present at the receiver. Another RFID system comprises an RFID signpost including a transmitter having a continuous power dissipation rating, and a processor for controlling the transmitter such that peak pulse power of a transmission from the transmitter multiplied by its duty cycle does not exceed the continuous power dissipation rating for the transmitter.

Abstract: A transponder unit of a DME ground apparatus receives an interrogation signal and converts the same to an IF signal. The unit performs analog-to-digital conversion on the IF signal, generating a digital interrogation signal. The unit calculates two detected outputs whose frequencies are ±900 kHz deviated with respect to the center frequency of the digital interrogation signal. Then, the transponder unit compares the two detected outputs and the digital interrogation signal in terms of magnitude, thereby to determine whether a response signal should be transmitted.

Abstract: A device and a method for eliminating interference between a radar working on the L frequency band and an aeronautical radio navigation equipment item, such as DME (Distance Measurement Equipment). When the radio navigation equipment operates, the radar emits periodically in all or part of the frequency band and then halts its emissions, each emission has a given duration and being separated from the previous emission by an interval of silence.

Abstract: An oscillation maintenance circuit for a half-duplex transponder that has an LC resonant circuit, a storage capacitor and a rectifier connected to charge the storage capacitor with a rectified oscillation signal, having an end-of-burst detector providing an end-of-burst signal when the amplitude of the oscillation signal has dropped below a predetermined threshold. A clock regenerator provides a clock signal derived from the oscillation signal. Switching means controlled by the clock signal in the presence of the end-of-burst signal connect the storage capacitor with LC resonant circuit through at least one current limiting resistor during part of the period of the clock signal, in such a manner that energy is fed into the LC resonant circuit.

Abstract: Each of plural detection units performs a signal transmission-reception operation responding to at least one of a plurality of kinds of operation timing signals repeated at a predetermined periodicity. The number of continuous reception times of the reflection signal is counted and used to determine obstacle detection when the number of counts is larger than or equal to a predetermined value. The transmission-reception operations are controlled by an operation timing signal having a periodicity shorter than the predetermined periodicity.

Abstract: By using the delay profile created by delay profile creating section 102 and the first threshold value 330 received from the first threshold value calculation 105, the first threshold value timing detection section 103 selects only the earliest receive timing exceeding the first threshold value, from all the timing that the correlation value in the delay profile becomes a maximum. By using the receive timing and the second threshold value 331 received from the second threshold value calculation section 107, reference timing calculation section 106 selects the reference timing required for calculating the receive timing for the incoming wave of the minimum propagation delay time. The timing delayed by previously set timing behind said reference timing is sent from receive timing calculation section 108 as the receive timing 113 of the incoming wave of the minimum propagation delay time.

Abstract: A device and a method for triggering at least one deceleration device and/or one output-determining actuator element of a vehicle propulsion system, in particular for automatic longitudinal vehicle regulation, a first surroundings sensing device being provided, which delivers longitudinal value-optimized measured values, a second surroundings sensing device being provided, which delivers object lateral dimension-optimized measuring values, and an analyzer device being provided, which receives the output signals of the first and second surroundings sensing devices and the measured values of the first and second surroundings sensing devices being used for object identification. The device and the method are furthermore suitable for initiating or performing vehicle deceleration for collision avoidance or for alleviating the severity of a collision.

Abstract: A hybrid air-ground vehicle design that cycles through a regenerative energy phase during a ground-based trajectory. The regenerative ground-based trajectory, in turn, produces energy for purposes of implementing another air-based trajectory cycle. The design significantly improves the versatility and endurance of robotic position-adaptive sensor designs. The radar (or electro-optic) sensors on the platform perform surveillance operations during both the ground and air trajectories of the hybrid air/ground vehicle.

Abstract: A detector for detecting the presence of a memory tag, the detector comprising a radio frequency source operable to generate a radio frequency signal and a detector resonant circuit part connected to the radio frequency source, the detector resonant circuit part comprising an antenna, the detector further comprising a power monitor responsive to the power of a reflected signal returned from the detector resonant circuit part, the power monitor being operable to generate an output in response to the power of the reflected signal, wherein a decrease in the power of the reflected signal indicates the presence of a tag in the vicinity of the antenna.

Abstract: Communication between a remote locator and a transponder is used to determine the relative position of the transponder. The transponder and locator each include a transmitter and a receiver. The locator transmits an inquiry in the form of a relatively powerful cyclically encoded signal with repetitive elements, uniquely associated with a target transponder. Periodically, each transponder correlates its coded ID against a possible inquiry signal, determining frequency, phase and framing in the process. Upon a match, the transponder transmits a synthesized response coherent with the received signal. The locator integrates multiple cyclical response elements, allowing low-power transmissions from the transponder. The locator correlates the integrated response, determines round-trip Doppler shift, time-of-flight, and then computes the distance and angle to the transponder. The transponder can be wearable, bionically implanted, or attached to, or embedded in, some object.

Abstract: There is provided a method and system for positioning a transponder, the system comprising an antenna array of at least two spaced-apart antennas coupled to a common generating and switching unit. The generating and switching unit is configured for generating a periodic signal and switching the signal between said at least two antennas, constituting a positioning signal transmitted to the transponder. The system comprises a receiver for receiving a returned signal and a phase difference estimator coupled to the receiver and operable to measure phase differences between portions of the returned signal. The system further comprises a positioning utility coupled to said phase difference estimator and configured to determine the position of the transponder relative to the positioning system.

Abstract: A system for identifying radio-frequency identification (RFID) devices is described. In one embodiment, RFID devices include an antenna and metallic pattern printed on a substrate. A probing platform is used to radiate the RFID devices with an electromagnetic signal (e.g., radio-frequency signal, microwave signal, etc.). Each RFID device generates a quantifiable backscatter depending on the unique impedance of the passive RFID device in response to the electromagnetic signal. The backscatter is employed to uniquely identify the passive RFID device's impendence with respect to the probing platform uniquely characterized at predetermined frequencies of the electromagnetic signal.

Abstract: A detecting device for detecting moving target vehicles from a moving host vehicle, comprising a first detector means mounted to the host vehicle and aligned to a stationary target area for generating at least a first output representative of the stationary target area at least at a time T1, a second detector means mounted to the host vehicle and aligned to the stationary target area for generating at least a second output representative of the stationary target area at least at a time T2, and a control system to receive the first and second outputs and to compare the first output at T1 to the second output at T2 to identify any differences between the outputs, whereby a target vehicle moving in the stationary target area may be detected.

Abstract: Systems and methods for reducing radar target processing. The systems include a processor configured to receive a first input from a cooperative surveillance source and a second input from a radar device. The first input includes cooperative target information, the second input includes cooperative and non-cooperative target information, and the processor is configured to process the first and second inputs to remove cooperative target information from the second input based on the first input to generate a modified radar output for use by an output device. The methods include receiving a first input including cooperative target information from a cooperative surveillance source, receiving a second input including cooperative and non-cooperative target information from a radar device, processing the first and second inputs to remove cooperative target information from the second input based on the first input, and generating a modified radar output based on the processed first and second inputs.

Abstract: A system for tracking an object in space for position, comprises a transponder device connectable to the object. The transponder device has one or several transponder aerial(s) and a transponder circuit connected to the transponder aerial for receiving an RF signal through the transponder aerial. The transponder device adds a known delay to the RF signal thereby producing an RF response for transmitting through the transponder aerial. A transmitter is connected to a first aerial for transmitting the RF signal through a first aerial. A receiver is connected to the first, a second and third aerials for receiving the RF response of the transponder device therethrough. A position calculator is associated to the transmitter and the receiver for calculating a position of the object as a function of the known delay and the time period between the emission of the RF signal and the reception of the RF response from the first, second and third aerials. A method is also provided.

Abstract: By using the delay profile created by delay profile creating section 102 and the first threshold value 330 received from the first threshold value calculation 105, the first threshold value timing detection section 103 selects only the earliest receive timing exceeding the first threshold value, from all the timing that the correlation value in the delay profile becomes a maximum. By using the receive timing and the second threshold value 331 received from the second threshold value calculation section 107, reference timing calculation section 106 selects the reference timing required for calculating the receive timing for the incoming wave of the minimum propagation delay time. The timing delayed by previously set timing behind said reference timing is sent from receive timing calculation section 108 as the receive timing 113 of the incoming wave of the minimum propagation delay time.

Abstract: There are presented various approaches to monitor performance of RF systems and circuitry such as those used in aircraft transponders. Such monitoring may be designed to verify operational performance of transponders as set forth by FAA regulations, or may be used to periodically or continually monitor integrity of transponder performance. Data may be collected by such periodic or continual monitoring, and may be analyzed to identify potentially troublesome trends in transponder performance, allowing early intervention or repair, if warranted.

Abstract: A direction estimating section estimates the incoming direction of a radio wave from an RFID tag in each of antennas. A position calculating section calculates the position of the RFID tag on the basis of the incoming direction of the radio wave estimated in the direction estimating section.

Abstract: A directional warning system and a method of warning of friendly forces. In one embodiment, the system includes: (1) a conductive shield having an opening at an end thereof and a radio frequency absorptive material located on an inner surface thereof, (2) a Luneberg lens located within the conductive shield and (3) a plurality of feed horns located proximate a portion of the Luneberg lens that is distal from the opening and arranged relative thereto based on a zone-of-interest with which the directional warning system may be associated.

Abstract: The present invention relates to a system and a method for location determination using time differences. The method of the invention comprises the steps of: transmitting a transmission signal by using a directional transmitter rotating at an angular velocity, the transmission signal comprising a transmission identification and the transmitting time; receiving the transmission signal by using an omnidirectional transceiver, and adding a personal identification to the transmission signal to be a response signal; transmitting the response signal; receiving the response signal by using an omnidirectional receiver and recording the receiving time; and calculating the location of the omnidirectional transceiver corresponding to the directional transmitter according to the difference between the receiving time and the transmitting time.

Abstract: An RFID circuit comprises an RF carrier signal source, a hybrid coupled to the RF carrier signal source operable to generate an in-phase and a quadrature phase component of the RF carrier signal, a switch coupled to the hybrid operable to pass one of the in-phase and quadrature phase components of the RF carrier signal to its output, and a mixer coupled to the output of the switch operable to multiply one of the in-phase and quadrature phase component of the carrier signal and a received modulated carrier signal and generate a baseband signal.

Abstract: An active device includes a receiving antenna (6) that receives an electromagnetic (2) signal coming from a localisation system (3) and at least one emitting antenna (8) that 5 resends said signal (2) to said localisation system (3), and is characterised in that said device (4) includes a plurality of said emitting antennae (8) connected to at least one receiving antenna (6) in such a way that said emitting antennae (8) receive the electromagnetic (2) signal coming 10 from said at least one receiving antenna (6) with each of said emitting antennae (8) being the ones that resend the signal (2) to said localisation system (3). This offers the possibility of creating artificial measuring points that are retained over time easily, cheaply and simply, 15 whether in wooded zones, snow-covered zones or at sea.

Abstract: There is provided a system and method for positioning a receiver, the system comprising an antenna array coupled to a common generating and switching unit. The generating and switching unit is configured to generate a periodic signal and to switch the signal between at least two antennas, constituting a positioning signal; such that an RF receiver receiving the positioning signal and having a phase difference estimator is capable to measure phase differences between portions of the positioning signal transmitted by the spaced-apart antennas, the phase differences indicating the orientation of the received relative to the positioning system.

Abstract: An adaptive inductive ballast is provided with the capability to communicate with a remote device powered by the ballast. To improve the operation of the ballast, the ballast changes its operating characteristics based upon information received from the remote device. Further, the ballast may provide a path for the remote device to communicate with device other than the adaptive inductive ballast.

Abstract: A radiocommunication apparatus includes a transmitting device and a receiving device. The transmitting device includes a first local oscillation section for selecting a frequency for a first local oscillation signal from a plurality of predetermined frequencies in order to output the first local oscillation signal, and a first frequency mixing section for mixing an input signal and the first local oscillation signal, thereby forming a transmission signal. The receiving device includes a second local oscillation section for selecting a frequency for a second local oscillation signal from the plurality of predetermined frequencies in order to output the second local oscillation signal, and a second frequency mixing section for mixing a received signal and the second local oscillation signal, thereby forming an output signal.

Abstract: A transmitter provides a plurality of output signals. The transmitter includes a processor, a modulator, a first circuit, and a second circuit. The modulator provides a modulated signal responsive to the processor. The modulated signal includes an amplitude modulated radio frequency for transmitting a pulse. The first circuit provides a first output signal, responsive to and with higher power than the modulated signal. The first output signal has a first phase during transmitting of the pulse. The second circuit provides a second output signal, responsive to and with higher power than the modulated signal. The second output signal has a second phase during transmitting of the pulse. The second phase is controlled by the second circuit in accordance with the first phase, the second phase, and indicia of a third phase provided by the processor.

Abstract: A vehicle detector includes a detecting apparatus and a determining apparatus. If a plurality of detection points detected by the detecting apparatus forms a group of detection points, the determining apparatus sets a determining virtual window encompassing the group of detection points and determines whether the group of detection points is likely to represent the one vehicle based on a state of movement of the group of detection points with respect to the determining virtual window.

Abstract: A system and method for monitoring topological changes in a defined area. A grid of sensors is arranged in the area, with known distances between them. The sensors communicate wirelessly with a host computer, which individually addresses each sensor to instruct that sensor to be in an interrogate mode or responder mode. When a sensor is in interrogate mode, it measures distance from a neighboring sensor using radar (continuous wave phase difference) measurements. When a sensor is in responder mode, it receives, delays, and returns a signal received from a neighboring sensor.

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: Wireless remote control system for engine piston with in-piston circuit (50) and an external processing unit mounted on the exterior of the crank case (51). A carrier signal generated in the external processing unit is fed to a primary coil (P) located within the crank case and the secondary coil (S), loosely coupled to coil (P) and tuned for resonance therewith is located in the skirt of the piston. The secondary coil picks up a carrier signal from the primary coil and the carrier signal is rectified, smoothed and regulated to provide DC power to a micro controller in the piston circuit. The micro controller may use data from a number of sensors to modulate the signal in the secondary coil, which modulation is picked up by the primary coil and thus sensor data is transmitted to the external processing unit where it is filtered and decoded.

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: The invention relates to a system, device, and method for using radar signals to measure the distance (h) to a surface from said device, the device comprising a transmitter and a transmitting antenna for transmitting radar signals, and a receiver and a receiving antenna for receiving a radar signal. The device may also comprise a first additional reflecting object separate from the receiving antenna, which additional reflector is designed so as to introduce a first predetermined alteration in radar signals upon reflection, with the device being equipped with means to differ between received signals with and without said predetermined alteration. The first predetermined alteration introduced by the first separate reflector can be, for example, a modulation shift or a shift in the polarization of the signal. In a typical embodiment the additional reflector is located close to the radar unit creating a double transition from radar unit to the surface.

Abstract: A series of radio frequency identification (RFID) systems are delineated. One such RFID system comprises an RFID signpost, and a plurality of infrared transmitters, wherein each infrared transmitter of the plurality of infrared transmitters is arranged to cover, when transmitting, a distinct sector relative to the RFID signpost. Another RFID system comprises an RFID signpost having a transmitter for transmitting signals of a predefined type, and a receiver for receiving signals of the predefined type, wherein the transmitter for transmitting signals of the predefined type cannot transmit until a determination is made that the predefined type of signal is not present at the receiver.

Abstract: Systems and methods for alerting surrounding aircraft if a ground-based unit is a threat. One example system is located on a ground-based unit. The system includes a position sensor that senses position of the ground-based unit, a memory that stores predefined threat zone information, a transmitter that transmits a predefined transponder signal, and a processor in data communication with the position sensor, the memory, and the transmitter. The processor instructs the transmitter to transmit the transponder signal based on the threat zone information and the sensed position of the ground-based unit.

Abstract: System and method for disabling a RFID tag. A preferred embodiment comprises attenuating a signal received at an antenna of the RFID tag based upon a status of the RFID tag and responding to an instruction in the received signal if the attenuated signal is detectable. The attenuation of the received signal requires that the received signal have a signal strength greater than a specified threshold in order for the instruction in the received signal to be detectable. This means that for a given signal transmit power, the RFID tag must be within a certain distance from a RFID reader attempting to retrieve information from the RFID tag. By setting the attenuation amount at a sufficiently high level, the method ensures that the RFID reader must be substantially adjacent to the RFID tag, preventing the unintended retrieval of unique identification information by RFID readers remotely located from the RFID tag.

Abstract: There are provided a differential processing unit which performs differential processing for a Mode S transponder transmission signal, an auto correlation arithmetic operation unit which performs an arithmetic operation of a degree of auto correlation between an increasing change rate and decreasing change rate of a power level in the signal which has been subjected to the differential processing, a pulse regeneration unit which regenerates a pulse based on the degree of auto correlation, which has been obtained by the auto correlation arithmetic operation processing, a pulse phase locked loop unit which performs gate processing and phase locked processing for the regenerated pulse, and a pulse decoding unit which decodes the Mode S transponder transmission signal based on the pulse which has been subjected to the gate processing and the phase locked processing.

Abstract: Interfering clutter in radar pulses received by an airborne radar system from a radar transponder can be suppressed by developing a representation of the incoming echo-voltage time-series that permits the clutter associated with predetermined parts of the time-series to be estimated. These estimates can be used to estimate and suppress the clutter associated with other parts of the time-series.

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: The present invention is a combined aircraft TCAS/Transponder with common antenna system and transmitter. Common TCAS/Transponder multi-monopole top and bottom antennas may be connected to a top and bottom antenna modules, the top and bottom antenna modules being electrically coupled to the combined TCAS/Transponder transmitter/receiver block through connection lines.

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: A system and method of using a standard ADS-B transmitter and encoder to identify targets to provide a collision avoidance system, wherein the method includes the steps of providing a standard ADS-B transmitter and encoder, a phase modulator including a digital synthesizer, radio-frequency electronics, antennas, and a radar transceiver; synthesizing digital-based band signals from the ADS-B transmitter with additional random phase modulation using the digital synthesizer; using the antennas to both transmit and receive signals; and estimating angles-of-arrival for every target in a field-of-view. The method may include the steps of demodulating the signals received by the antennas, providing a digital signal processor, and performing matched filtering on received signals. The method may also include the step of estimating a target range of identified targets using the digital signal processor.

Abstract: The present invention applies to the surveillance of, in particular civil, air traffic, and more particularly, to cooperative aircraft ground systems which make it possible to pinpoint in radial distance and in azimuth the aircraft present in a certain volume and to interrogate them. A method and a device which makes it possible to determine a reference value of a response contained in a reception signal of a secondary radar, doing so even in the presence of strong pollution, in particular in the event of nesting between mode S responses.