Abstract: A ground-based antenna system includes a first phased array antenna to generate a first directional antenna beam at a first polarization, and a second phased array antenna to generate a second directional antenna beam at a second polarization. The first and second phased array antennas each include a lower antenna element row, an upper antenna element row, and medial antenna element rows therebetween. The ground-based antenna system further includes first and second antenna beam controllers cooperating with the first and second phased array antennas to generate a more steeply sloped phase taper associated with the lower antenna element row, a less steeply sloped phase taper associated with the medial antenna element rows, and a more steeply sloped phase taper associated with the upper antenna element row.

Abstract: A radar surveillance system is described in which the radar beam re-visits each area of interest after a short period of time, by electronically reconfiguring a scanned beam to an offset position for an interleaved sub-dwell, within a scan period. This ‘look-back’ capability, where the area under test is re-visited after approximately 1 second, allows the natural de-correlation of sea clutter to take place between the initial and look-back samples of the surveillance area. The re-visit time can be adjusted to best exploit the de-correlation characteristics of the sea clutter return.

Abstract: A device and method are provided for forming a beam of a transmit antenna array in the direction of a positioning receiver. Since the beam of the transmit antenna array is formed remotely by the positioning receiver, the received gain of the incoming positioning signal is maximized while signals from other directions are attenuated, thereby mitigating any unwanted effects of multipath. Depending on the number of elements in the transmit antenna array and their physical distribution, the width of the beam can be made finer such that the positioning receiver only requires a simple omni-directional antenna to achieve an accurate positioning solution.

Abstract: An embodiment relates to a method for processing input data that includes multiplying a portion of the input data with a first set of coefficients or with a second set of coefficients, wherein the first set of coefficients and the second set of coefficients are stored in a memory, wherein the first set of coefficients is used on phase modulated input data and wherein the second set of coefficients is used on input data that are not phase modulated.

Abstract: A direct geolocation approach for estimating a location of a stationary emitter located on the Earth surface is provided. The approach uses data collected during a plurality of time periods including Time Difference of Arrival (TDOA) and Frequency Difference of Arrival (FDOA) measurements of a radar pulse sent from the emitter, and altitude measurements of an aircraft above the Earth surface. The approach includes estimating a location of the emitter for each of the time periods based on the TDOA, FDOA, and altitude measurements associated with a respective time period. The estimated location of the stationary emitter includes possible longitude and latitude of the emitter. The approach further includes averaging the estimated locations associated with the plurality of time periods to form an averaged estimated location of the emitter. A convenient example of the approach computes the location of the emitter based on the averaged estimated location.

Abstract: A method is based on measuring a distance to a reference reflector arranged at a known distance, in order to calibrate and/or monitor a coherent frequency modulation, continuous wave radar, fill-level measuring device, wherein the reference reflector can be reliably identified. To this end, a reference reflector executing oscillations toward the fill-level measuring device with an oscillation frequency is used, which is inserted in the beam path of periodically linearly frequency modulated transmission signals transmitted from the fill-level measuring device. The fill-level measuring device receives fractions of the transmission signals reflected back on reflectors in the container and records based on these received signals and their time correlation relative to the respectively associated transmission signal for each received signal an echo function, which shows the amplitudes of the received signal as a function of the associated position of the associated reflector.

Abstract: At least two input signals, each characterizing a radio signal having a radio frequency (RF), are received. The input signals are converted into at least three output signals. The output signals have a unique combination of corresponding magnitudes for each RF phase difference between the input signals. A set of magnitudes corresponding to the output signals is measured using a mobile measuring device. An RF phase angle value is determined based the measured set of magnitudes. The RF phase angle value is converted into an angle value indicative of the direction of arrival of the radio signal.

Abstract: An image processing device which generates an image where a target object can be discriminated from an object other than the target object. An image processor (15), for echo signals read from a sweep memory (14), calculates a ratio of echo signals indicating a predetermined level or higher among the echo signals of a predetermined number of samples, and generates image data having a display element according to the calculated ratio. This ratio indicates a lower value for an object more isolated and a higher value for an object existing as a larger mass. The image processor (15)acquires color values according to the calculated ratio. Since the target object, such as a ship, is an isolated object and the ratio becomes low, the color values indicate red, and since inland is an object existing as a large mass and the ratio becomes high, the color values indicate green.

Abstract: A radar reception device is provided. The device includes a reception signal acquirer, a signal processor, a PPI-scope generator, an A-scope generator, a display output unit, and a user interface. The reception signal acquirer acquires, in an R?-coordinate system, a reception signal received by an antenna that rotates at a predetermined cycle. The signal processor performs signal processing on the reception signal in the R?-coordinate system according to a distance, and outputs the processed signal in the R?-coordinate system. The PPI-scope generator converts the processed signal from the R?-coordinate system into an XY-orthogonal coordinate system and generates a radar image in a PPI-scope. The A-scope generator generates a radar image where the reception signal before being signal-processed is illustrated in an A-scope. The display output unit displays the PPI-scope radar image and the A-scope radar image on a display unit simultaneously. The user interface accepts a user input.

Abstract: An ultra-broadband coherent radar transponder for precision tracking, and in particular a transponder arrangement having an antenna, receiver, control logic, delay, and transmitter components arranged to coherently amplify, delay and repeat back a reference signal to be utilized by a microwave radar system for high fidelity tracking.

Abstract: A ranging and positioning system comprising transmitters and receiver nodes communicating together by chirp-modulated radio signals, that have a ranging mode in which ranging exchange of signals takes place between a master device and a slave device that leads to the evaluation of the range between them. The slave is arranged for recognizing a ranging request and transmit back a ranging response containing chirps that precisely aligned in time and frequency with the chirps in the ranging requests, whereupon the master can receive the ranging response, analyze the time and frequency the chirps contained therein with respect to his own time reference, and estimate a range to the slave.

Abstract: In a method for detecting radar objects with the aid of a radar sensor of a motor vehicle, a transmitted signal has a sequence of frequency modulations, to each of which a partial signal of a measuring signal is assigned; first information about the relative velocity and the distance of a radar object is ascertained based on a frequency spectrum of at least one of the partial signals; second information about the relative velocity and the distance of the radar object is ascertained based on a frequency spectrum of a time curve of values of frequency spectra of the partial signals at a frequency position of the radar object in these frequency spectra; and the relative velocity and the distance of the radar object are ascertained based on matching of the first information with the second information.

Abstract: A method of advanced receiver autonomous integrity monitoring of a navigation system is discussed and two modifications facilitating its implementation in a hybrid navigation system are disclosed. In the first approach, relations describing the effect of unmodeled biases in pseudo-measurement on the Kalman filter state estimate are analytically derived and their incorporation into the integrity monitoring algorithm is described. The method comprises receiving a plurality of signals transmitted from space-based satellites, determining a position full-solution and sub-solutions, specifying a pseudorange bias, computing a transformation matrix for the full-solution and all sub-solutions using a Kalman filter, computing a bias effect on an error of filtered state vectors of all sub-solutions, and adding the effect to computed vertical and horizontal protection levels.

Abstract: Various exemplary embodiments relate to a method for detecting an object using radar system having M transmit antennas, N receive antennas, and a processor, including: receiving, by the processor, N×M digital signals, wherein the N receivers receive M received signals corresponding to M sequences of encoded transmitted signals resulting in N×M digital signals; processing the N×M digital signals to produce N×M first range/relative velocity matrices; applying a phase compensation to N×(M?1) first range/relative velocity matrices to compensate for a difference in range between the N×(M?1) first range/relative velocity matrices and the Mth range/velocity matrix; decoding the M phase compensated range/relative velocity matrices for the N receivers using an inverse of the transmit encoding to produce M decoded phase range/relative velocity matrices for the N receivers; detecting objects using the M range/relative velocity matrices for the N receivers to produce a detection vector.

Abstract: A ranging method, executed in a ranging device, comprising steps of: obtaining a trip time of a received wireless signal, wherein the received wireless signal is a wireless signal from an object; calculating a statistical value of a rising time of the received wireless signal; correcting the trip time according to the statistical value of the rising time; and estimating a distance between the object and the ranging device according to the corrected trip time.

Abstract: A method for detecting and mitigating errors in a positioning system includes receiving a first signal from a global navigation satellite system (GNSS) indicative of a first position and a second signal from the GNSS indicative of a second position of a machine, determining a difference between the first position and the second position, detecting an error in a current position of the machine when the difference between the first and the second position exceeds a threshold of one of (a) a maximum distance given a maximum velocity, and (b) an actual distance determined based on an output of an inertial sensor on the machine, and mitigating the detected error in the current position of the machine by switching from an output of the positioning system to a position output determined based upon the output of the inertial sensor to update the current position.

Abstract: Methods, systems, and computer readable media for mitigation of interference of GPS signals are disclosed providing selective mitigation of in-band interference implementing deterministic phase control. In one embodiment, a system for mitigating interference of GPS signals includes a pair of antennas, each receiving GPS signals that include both a desired signal component and a jammer signal component. The signal from one antenna is phase-shifted as needed to make it anti-phase with the signal from the other antenna, so that when the two signals are combined, the jammer signal components substantially cancel each other, leaving the desired signal components. Determining the phase shift required involves deterministically calculating the phase shift based on the amplitudes of the two input signals and the amplitude of the combined signal instead of the iterative techniques used in conventional systems.

Abstract: An apparatus includes a first array including sensors; a second array including sensors that are not collinear with the sensors of the first array except for a sensor that defines the origin of a spatial phase; and a signal processing unit that generates covariance matrices including a first covariance matrix and a second covariance matrix based on reflected waves received by the first and second arrays from targets, estimates first angles of the targets based on the first covariance matrix, reproduces an angle matrix based on the estimated first angles, performs triangular decomposition on the product of a generalized inverse matrix of the angle matrix and the second covariance matrix to obtain a matrix, constructs a similarity transformation problem from submatrices of the obtained matrix, and estimates second angles of the targets based on the estimated first angles and solutions of the similarity transformation problem.

Abstract: In a target recognition apparatus, a candidate detection section detects a target candidate, provided that a target exists in a basic detection area. A candidate addition section adds, regarding each target candidate detected in a folding area, a target candidate determined provided that the target candidate detected in the folding area is a virtual image, and a corresponding real image exists in an additional detection area. A tracking section determines, regarding each detected and added target candidate, presence/absence of a history connection with the target candidate detected in a past measurement cycle. A combination determination section determines, regarding each target candidate, presence/absence of a combination with an image target, based on whether or not an image target associated with the target candidate exists. A likelihood calculation section sets and updates a likelihood of a virtual image of the image target by using a determination result of the combination determination section.

Abstract: An apparatus comprising a plurality of radiating elements and a plurality of surface wave feeds. Each radiating element in the plurality of radiating elements comprises a number of surface wave channels in which each of the number of surface wave channels is configured to constrain a path of a surface wave. A surface wave feed in the plurality of surface wave feeds is configured to couple a surface wave channel in the number of surface wave channels of a radiating element in the plurality of radiating elements to a transmission line configured to carry a radio frequency signal.