Abstract: A method of detecting an unknown signal and estimating a source location of the unknown signal using aircraft based on an automatic dependent surveillance-broadcast (ADS-B) system is provided. The method includes a first step (S100) for obtaining from a plurality of airborne aircrafts provided with a network system, aircraft signals transmitted to an air traffic control (ATC) and a second step (S200) for detecting, by the ATC, a presence of an unknown signal in the aircraft signals based on one of a time difference of arrival (TDOA) method, a time of arrival (TOA) method, and an angle of arrival (AOA) method. The method further includes a third step (S300) for estimating the source location of the unknown signal and a fourth step (S400) for transmitting unknown signal generation information associated with the unknown signal and the source location of the unknown signal to neighboring aircraft and the ATC.

Abstract: An apparatus is disclosed herein for a cylindrically fed antenna and method for using the same. In one embodiment, the antenna comprises: an antenna feed to input a cylindrical feed wave; a first layer coupled to the antenna feed and into which the feed wave propagates outwardly and concentrically from the feed; a second layer coupled to the first layer to cause the feed wave to be reflected at edges of the antenna and propagate inwardly through the second layer from the edges of the antenna; and an array of plurality of surface scattering metamaterial antenna elements coupled to the second layer and have slots oriented either +45 degrees or ?45 degrees relative to the cylindrical feed wave impinging at a central location of each slot.

Abstract: Aspects of the disclosure provide a method of determining frame timing of one or more signals from one or more respective transmitters. The method determining first observation windows that correspond to first candidate segments of the one or more signals; calculating a first set of accumulated signal patterns, each accumulated signal pattern of the first set of accumulated signal patterns being calculated based on signal patterns in a respective subset of the first candidate segments of the one or more signals; determining whether a first set of accumulated synchronization words derived from the first set of accumulated signal patterns is consistent with a first set of corresponding benchmark synchronization words; and determining the frame timing of the one or more signals based on timing of the first observation windows when the first set of accumulated synchronization words is consistent with the first set of corresponding benchmark synchronization words.

Abstract: This determination method for determining a wrong synchronization including the steps of determining an ad hoc correlator corresponding to the value of correlation between the received signal and the local signal, and determining N additional correlators corresponding to the values of correlation between the received signal and an offset signal, each offset signal including a spreading code that is offset in relation to the local spreading code, and determining a value for the amount of inconsistency between the frequency of the local carrier wave and the frequency of the local spreading code; if the value of inconsistency is higher than a predetermined threshold value of inconsistency, determining a wrong synchronization; otherwise, determining an indicator of wrong synchronization as a function of the correlators determined, comparing the indicator of wrong synchronization with at least one threshold value, determining a wrong synchronization based on the result of the comparison.

Abstract: A satellite corrections generation system receives reference receiver measurement information from a plurality of reference receivers at established locations. In accordance with the received reference receiver measurement information, and established locations of the reference receivers, the system determines narrow-lane navigation solutions for the plurality of reference receivers. The system also determines, in accordance with the narrow-lane navigation solutions, at a first update rate, an orbit correction for each satellite of a plurality of satellites; at a second update rate, a clock correction for each such satellite; and at a third update rate that is faster than the second update rate, an update to the clock correction for each such satellite. Further, the system generates navigation satellite corrections for each such satellite, including the orbit correction updated at the first update rate, and the clock correction that is updated at the third update rate.

Abstract: Systems for maintain pointing of a phased array antenna in a direction maximizes to an extent possible the effective antenna gain is provided. The system includes a gyroscope and a Kalman Filter. The Kalman filter estimates an antenna pointing direction for each successive time step based on gyroscope readings and based on the results of a local search for maximum gain performed in the neighborhood of a previous antenna pointing direction.

Abstract: Jammer location is based on detected powers received by at least one receiver of signals from the satellite navigation system on board a carrier, by estimation, for each satellite, of the power of the noise at the output of each receiver according to the bearing and distance with respect to the carrier, a calculation of the sum of estimated powers, and extraction of the local maxima in terms of bearing and distance by using a synthetic aperture antenna carrying out a coherent integration of received signals in the direction of each bearing angle by using the known movement of the carrier, in which estimation of the power of the noise at the output of each receiver uses a plurality of coherent integrators and non-coherent integrators, with durations matched to the transit time of a source in the beam of the antenna for various distances for the non-coherent integrators.

Abstract: A GNSS receiver comprising a circuit configured to receive a positioning signal comprising a carrier modulated by a subcarrier and a PRN code; a subcarrier and code tracking loop, comprising a first discrimination circuit, configured to calculate a first pseudo range from said received positioning signal and a first reference signal; a code tracking loop, comprising a second discrimination circuit, configured to calculate a second pseudo range from said received positioning signal and a second reference signal; and a calculation circuit configured to evaluate a difference between said first pseudo range and said second pseudo range, and to modify the output of the first discrimination circuit accordingly. The invention further addresses a method for calculating a pseudo-range in such a GNSS receiver.

Abstract: A tracking device is provided and includes a processing unit that is in communication with a networking unit and a memory unit. The memory unit has executable instructions stored thereon, which, when executed, cause the processing unit to control the networking unit to coarsely identify a region currently occupied by a tracked device and determine an accurate location of the tracked device responsive to a predefined event.

Abstract: An electronic apparatus includes a controller that intermittently drives a receiver in a predetermined cycle, the receiver receiving a positioning signal to generate predetermined information, and the controller determines an upper limit of a period to be spent for the generation of the predetermined information on the basis of a period spent for the generation in the past.

Abstract: The present invention is directed to methods and apparatuses for beamforming signals or compute beamformed signals. The present approach is to determine a series of beams from or for a set of devices configured for receiving signals from and/or transmitting signals to one or more regions of interest in an n-dimensional space, with n=2 or 3. Each of the devices has a known position pi within said n-dimensional space. Signals are to be respectively transmitted or received non-uniformly in this space, i.e., according to the particular regions of interest. During a first phase, operations are performed in order to successively obtain a spatial filter function {circumflex over (?)}(r), a beamforming function ?(p), and beamforming weights ?(pi). The spatial filter function {circumflex over (?)}(r) matches projections of the regions of interest onto an n?1-dimensional sphere centered on said set of devices.

Abstract: Techniques and mechanisms to transmit signals with an antenna array. In an embodiment, a first signal is received at a first input of the first antenna while a second signal is received at a second input of the second antenna. A difference in phase differentials—the phase differentials each between the first signal and the second signal—results from propagation of the first signal and the second signal in the antenna array and from a difference between respective configurations of the first antenna and the second antenna. Each of the first antenna and the second antenna has respective emitters distributed along the length thereof. In another embodiment, the first antenna and the second antenna have different respective dielectric structures or different respective distributions of emitters.

Abstract: A ground-based source of a jamming signal capable of disrupting a GNSS satellite-based navigation system, for example a GPS jammer, is located with a detector carried by a suitable platform, for example an airborne UAV or missile. The detector, when the platform is at a first location, measures a characteristic of the jamming signal. The platform and its detector are then moved to a chosen second location, from which a further measurement of the jamming signal is made. The measurements made by the detector are then used to determine the location of the source of the jamming signal.

Abstract: A method for receiving and processing satellite navigation signals includes receiving the navigation signals; converting the navigation signals into digital signals; providing a clock signal to all channels that process the digital signals; generating frequency division signals; selecting a channel frequency division signal from the frequency division signals based on which ADC is used to convert the satellite navigation signals into digital signals; connecting the channel to the ADC; generating code frequency signal and base carrier frequency signal using a net accumulation signal; processing the digital signal in the channel to produce digital quadrature signal components of the digital signal based on the code frequency signal and the base carrier frequency signal; using a tick signal that represents 2N×clock signal as a temporary time scale for control of the channels for determining digital signal phase differences between the channels; and outputting coordinates based on the quadrature components.

Abstract: A phased array antenna system includes a plurality of radio frequency (RF) tile sub-arrays. Each RF tile sub-array includes a multiplicity of RF elements, a tile control integrated circuit, a multiplicity of RF integrated circuits and a configuration storage device. The configuration storage device stores data including calibration and configuration information that is unique to the RF tile sub-array and the tile control integrated circuit. The multiplicity of RF integrated circuits, the multiplicity of RF elements, and the configuration storage device are disposed on a single associated RF tile sub-array. The system also includes an antenna controller configured to process data for steering or tracking one or more RF beams by the multiplicity of RF elements. The calibration and configuration information that is unique to the RF tile sub-array is downloaded from the configuration storage device through the tile control integrated circuit to an RF element compensation table.

Abstract: A method for applying GPS UAV attitude estimation to accelerate computer vision. The UAV has a plurality of GPS receivers mounted at fixed locations on the UAV. The method includes receiving raw GPS measurements from each GPS satellite in view of the UAV, the raw GPS measurements comprising pseudo-range and carrier phase data representing the distance between each GPS receiver and each GPS satellite. Carrier phase and pseudo-range measurements are determined for each GPS receiver based on the pseudo-range and carrier phase data. The GPS carrier phase and pseudo-range measurements are compared pair-wise for each pair of GPS receiver and satellite. An attitude of the UAV is determined based on the relative distance measurements. A 3D camera pose rotation matrix is determined based on the attitude of the UAV. Computer vision image search computations are performed for analyzing the image data received from the UAV in real time using the 3D camera pose rotation matrix.

Abstract: GNSS receivers and methods of determining a current receiver state of a GNSS receiver are provided. The method includes receiving positioning signals from a plurality of satellites; generating a plurality of correlation grids from the received positioning signals, where each correlation grid is associated with a respective one of the plurality of satellites; estimating a probability distribution of the current receiver state from the plurality of correlation grids; and determining a maximum likelihood estimate of the current receiver state from the estimated probability distribution.

Abstract: A geolocation system on a platform, for example, an airplane, to identify a location of a signal emitting site includes an inertial navigation system and an array of signal detectors. A first subset of the detectors is on a flexing portion of the platform and a second subset of detectors is on a rigid portion of the platform. An inertial measurement unit is disposed adjacent to each of the detectors on the flexing portion. A locator module is configured to: calculate a respective velocity and a respective position of each one of the detectors positioned on the flexing portion as a function of respective inertial measurement data; and determine a position of the emitter as a function of the calculated velocity, calculated position, inertial navigation data, the detected signal data and data defining a flexure relationship between the flexing and rigid portions of the platform.

Abstract: A method and a receiver apparatus allows obtaining accurate estimates of motion parameters of a mobile receiver, including smoothed estimates of total coordinates increments relative to its initial position, projections of velocity vector and acceleration vector. High estimation accuracy is achieved by filtering the biased or unbiased estimates of total coordinate increments relative to the receiver's initial position using smoothing tracking filters of a 2-nd or 3-rd order.

Abstract: An antenna system includes an electromagnetic radiator assembled on a ground plane. The ground plane containing a nontransparent area in a center of the ground plane and a semitransparent area surrounding the nontransparent area. The nontransparent area is circular in shape. The semitransparent area is generally circular in shape and contains at least one slot. A plurality of vertical conducting elements are in proximity of a boundary between the nontransparent area and the semitransparent area on a bottom side of the ground plane. The vertical conducting elements are arranged in a circle around a center of the electromagnetic radiator.