Abstract: A radar sensor for motor vehicles. The radar sensor includes an antenna arrangement having multiple antenna elements linearly arranged at uniform distances along a connecting line, the distance between each two adjacent antenna elements being equal to half of the mean wavelength ? of the emitted radar signal, and the arrangement including at least one triple of adjacent antenna elements, in which the two antenna elements located on the outside in the triple, on the one hand, and the interposed antenna element, on the other hand, originate in opposite directions from the connecting line. The antenna arrangement includes at least one pair of antenna elements which originate in opposite directions from the connecting line and whose distance from one another is an integer multiple of the wavelength ?, so that one of these antenna elements has a negative amplitude taper in relation to the antenna elements of the triple.

Abstract: A radar includes a transmitter antenna unit including a plurality of transmitter antennas based on a first horizontal interval and a first vertical interval, a receiver antenna unit including a plurality of receiver antennas arranged based on a second horizontal interval, a transceiver configured to transmit a transmission signal through the transmitter antenna unit and receive a reflection signal reflected from a target object through the receiver antenna unit and a processing unit configured to extract information about the target object by processing the received reflection signal. The second horizontal interval is smaller than the first horizontal interval.

Abstract: A device may include a receive antenna input to couple a receive antenna to a receive chain of the device. The device may include a test signal generator to generate a test signal. The device may include a signal coupler between the receive antenna input and the receive chain. The signal coupler may include a first port to inject the first test signal into the receive antenna via the receive antenna input. The device may include a control circuit to monitor an impedance matching of the receive antenna based on one or more characteristics of a reflected signal resulting from the first test signal being injected into the receive antenna. The one or more characteristics of the reflected signal may be dependent on the impedance matching of the receive antenna.

Abstract: A radar device for a vehicle includes: two or more receiving channels, each of which includes a mixer. At least one or more of the receiving channels includes: a phased array antenna divided into at least two or more branches to provide sub-array antenna elements; and a first phase shifter and a variable gain amplifier as a high frequency unit disposed between each of the sub-array antenna elements and the mixer. A numerical number of the sub-array antenna elements is equal to or more than a numerical number of the high-frequency units.

Abstract: Examples disclosed herein relate to a radar system and method of angular resolution refinement for use in autonomous vehicles. The method includes transmitting a radio frequency (RF) beam to a surrounding environment with a beamsteering radar system and receiving return RF beams from the surrounding environment. The method also includes generating radar data from the return RF beams and detecting objects from the radar data, and determining a direction of arrival of each of object and determining an angular distance between the objects. The method further includes initiating a guard channel detection based at least on the angular distance and determining gain amplitudes of the return RF beams, and determining a null between the objects from the gain amplitudes and resolving the objects as separate objects based at least on the determined null. The method also includes determining a refined direction of arrival of the objects based at least on the resolved objects.

Abstract: Reception antennas include first antennas at positions different in a first direction, second antennas at positions different in a second direction perpendicular to the first direction, and a third antenna different from the first or second antenna. The first and second antennas include one overlapping antenna. The third antenna is arranged at a position different in the second direction from a position of the first antennas. The third antenna is arranged at a position a prescribed spacing apart in the first direction from a position of the second antennas. At least one spacing of the first antennas is the prescribed spacing. Transmission antennas include fourth antennas arranged in the first direction and fifth antennas arranged in the second direction. The fourth antennas and the fifth antennas include one overlapping antenna. A spacing of the fourth antennas is wider in the first direction than an aperture length of the first antennas.

Abstract: One of a transmitting array antenna and a receiving array antenna includes a first antenna group and a second antenna group. The first antenna group includes one or more first antenna elements of which the phase centers of the antenna elements are laid out at each first layout spacing following a first axis direction, and a shared antenna element. The second antenna group includes a plurality of second antenna elements and the one shared antenna element, and the phase centers of the antenna elements are laid out in two columns at each second layout spacing following a second axis direction that is different from the first axis direction. The phase centers of the antenna elements included in each of the two columns differ from each other regarding position in the second axis direction.

Abstract: An electromagnetic wave medical imaging system, the system including: at least one antenna; transmission electronics; receiving electronics; and receiving computing electronics, where the transmission electronics are structured to transmit a first electromagnetic wave having an Orbital Angular Momentum wave-front thru the antenna towards a target, where the Orbital Angular Momentum wave-front includes a vortex region, where the transmission electronics are structured to transmit a second electromagnetic wave having a non Orbital Angular Momentum wave-front thru a first portion of the antenna towards the target, where the receiving electronics are structured to form a first signal from a first return wave of the first electromagnetic wave, where the receiving electronics are structured to form a second signal from a second return wave of the second electromagnetic wave, and where the receiving computing electronics includes a computing process to estimate the return wave associated with the vortex region.

Abstract: A fast ramp frequency modulated continuous wave (FMCW) radar system is described herein, where the fast ramp FMCW radar system is configured to employ velocity labeled multiplexing (VLM) in connection with generating detections for objects in a scene. Transmitters in the radar system are assigned different velocity labels that corresponds to different phase rates of change of consecutive chirps in signals emitted by the transmitters. Approaches for generating detections based upon echo signals that correspond to the emitted signals are also described herein.

Abstract: An angle measuring device includes: a signal extracting unit for extracting a signal that includes a first reflection wave and does not include a second reflection wave as a first demodulated signal and a signal that includes the second reflection wave and does not include the first reflection wave as a second demodulated signal from reception signals output from one or more reception antennas among a plurality of reception antennas; an elevation calculating unit for calculating an elevation of a target by performing monopulse angle measurement using a sum signal of the first demodulated signal and the second demodulated signal and a difference signal between the first demodulated signal and the second demodulated signal; and an azimuth calculating unit for calculating an azimuth of the target using reception signals output from the plurality of reception antennas.

Abstract: A radar sensor device including a first radar sensor arrangement configured to measure a fill level of a medium in a container and a second radar sensor arrangement configured to monitor an environment of the radar sensor outside the container.

Abstract: A method including: detecting that an aerial vehicle is located at a reference axis of a sensor, or at a predetermined or calculated angle of the reference axis of the sensor, the method further comprising, by a processor and memory circuitry: obtaining a given position Paerial of the aerial vehicle upon its detection at the reference axis of the sensor, or upon its detection at the predetermined or calculated angle of the reference axis of the sensor, and position Psensor of the sensor, and determining, based at least on Paerial and Psensor, a cardinal direction with respect to the reference axis.

Abstract: Various embodiments include methods and systems having detection apparatus operable to cancel or reduce leakage signal originating from a source signal being generated and transmitted from a transmitter. A leakage cancellation signal can be generated digitally, converted to an analog signal, and then subtracted in the analog domain from a received signal to provide a leakage-reduced signal for use in detection and analysis of objects. A digital cancellation signal may be generated by generating a cancellation signal in the frequency domain and converting it to the time domain. Optionally, an estimate of a residual leakage signal can be generated and applied to reduce residual leakage remaining in the leakage-reduced signal. Additional apparatus, systems, and methods can be implemented in a variety of applications.

Abstract: This document describes techniques and systems directed at slow-time modulation for multiple radar channels. A set of transmit channels are modulated using code sequences to phase-modulate transmission signals. A second set of transmit channels are modulated using the same codes for phase modulation as well as using a frequency phase shift. Demodulation is achieved by multiplying received signals by the code sequences. Fast Fourier transforms (FFT) are applied to the received signals to generate a range-Doppler map for each receive channel. A non-coherent integration is performed on the range-Doppler maps to form a range-Doppler average map. The range-Doppler average map is shifted by the frequency phase shift, and the minimal of the range-Doppler average map and the shifted range-Doppler average map is retained. These techniques may reduce the impact of signal residue and increase angular resolution by enabling multiple transmit channels to be utilized.

Abstract: The vehicle radar apparatus may include a transmitting array antenna configured to radiate radar signals for forward detection, N receiving array antennas configured to receive the radar signals reflected from a target after being radiated from the transmitting array antenna, and a control unit configured to estimate an azimuth of the target by using non-offset receiving array antennas among the N receiving array antennas and estimate an elevation of the target by using a phase difference between an offset receiving array antenna and the non-offset receiving array antenna among the N receiving array antennas and the azimuth of the target.

Abstract: Systems and methods are provided for a digital beamformed phased array feed. The system may include a radome configured to allow electromagnetic waves to propagate; a multi-band software defined antenna array tile; a power and clock management subsystem configured to manage power and time of operation; a thermal management subsystem configured to dissipate heat generated by the multi-band software defined antenna array tile; and an enclosure assembly. The multi-band software defined antenna array tile may include a plurality of coupled dipole array antenna elements; a plurality of frequency converters; and a plurality of digital beamformers.

Abstract: An object detector includes: a transmission and reception unit that transmits a transmission wave and receives a reflection wave from an object; an acquisition unit that detects the reflection wave having a signal level above a threshold to acquire distance information indicating a distance from the transmission and reception unit to the object; a sort processing unit that sets a priority of the distance information to be higher as a difference between a signal level corresponding to the distance information and the threshold is larger when a plurality of pieces of the distance information are acquired in a predetermined period; and an output control unit that outputs the plurality of pieces of the distance information in descending order of the priority.

Abstract: A mobile radar system for visualizing forward looking topography is configured with at least two phased-array antennas to form a forwarding looking phased-array interferometer.

Abstract: One of a transmitting array antenna and a receiving array antenna includes a first antenna group and a second antenna group. The first antenna group includes one or more first antenna elements of which the phase centers of the antenna elements are laid out at each first layout spacing following a first axis direction, and a shared antenna element. The second antenna group includes a plurality of second antenna elements and the one shared antenna element, and the phase centers of the antenna elements are laid out in two columns at each second layout spacing following a second axis direction that is different from the first axis direction. The phase centers of the antenna elements included in each of the two columns differ from each other regarding position in the second axis direction.

Abstract: An electromagnetic wave medical imaging system, the system including: at least one antenna; transmission electronics; receiving electronics; and receiving computing electronics, where the transmission electronics are structured to transmit a first electromagnetic wave having an Orbital Angular Momentum wave-front thru the antenna towards a target, where the transmission electronics are structured to transmit a second electromagnetic wave having a non Orbital Angular Momentum wave-front thru a first portion of the antenna towards the target, where the receiving electronics are structured to form a first signal from a first return wave of the first electromagnetic wave, where the receiving electronics are structured to form a second signal from a second return wave of the second electromagnetic wave, and where the system is designed to operate at a near field electromagnetic wave. Included are methods for operating a super resolution system.

Abstract: In one embodiment, a method is provided. The method comprises determining a free space path loss distance at a frequency of a transmitter; determining a morphology class for a geographic location of the transmitter; determining a scaling factor P corresponding to the determined morphology class; determining a circular analysis region based upon the scaling factor P; and generating a contour.

Abstract: A method and a radar system are provided in the present disclosure. The radar system includes a radar unit having an antenna array configured to transmit and receive radar signal and a memory configured to store radar calibration parameters and radar channel parameters corresponding to the radar unit. The method provides for operation of the radar system. The radar system also includes a radar processor. The radar processor is configured to cause transmission of radar signals by the antenna array based on the radar channel parameters. The radar processor is also configured to process received radar signals based on the radar calibration parameters. The radar system further includes a central vehicle controller configured to operate a vehicle based on the processed radar signals.

Abstract: A radar includes a transmitter antenna unit including a plurality of transmitter antennas arranged in a diagonal direction based on a first horizontal interval and a first vertical interval, a receiver antenna unit including a first receiver antenna group and a second receiver antenna group arranged based on the first horizontal interval, a transceiver configured to transmit a transmission signal through the transmitter antenna unit and receive a reflection signal reflected from a target object through the receiver antenna unit and a processing unit configured to extract information about the target object by processing the received reflection signal.

Abstract: A super resolution system, the system including: at least one antenna; transmission electronics; receiving electronics; and receiving computing electronics, where the transmission electronics are structured to transmit a first electromagnetic wave having an Orbital Angular Momentum wave-front thru the antenna towards a target, where the transmission electronics are structured to transmit a second electromagnetic wave having a non Orbital Angular Momentum wave-front thru a first portion of the antenna towards the target, where the receiving electronics are structured to form a first signal from a first return wave of the first electromagnetic wave, where the receiving electronics are structured to form a second signal from a second return wave of the second electromagnetic wave, and where the receiving computing electronics are structured to compute target information by using at least one difference between the first signal and the second signal.

Abstract: Aspects relate to a calibration of an antenna array module of a wireless communication device in open space. The antenna array module may be used as a proximity sensor to detect an object's proximity relative to the antenna array module. Aspects include displaying an open space calibration instruction on a display of the wireless communication device, transmitting a proximity test signal from the antenna array module, measuring a value of a first signal received at the antenna array module in response to transmitting the proximity test signal, and storing the value of the first signal as an open space calibration value of the antenna array module. The first signal may be measured at cross-polarized antennas of the antenna array module. The value of the first signal may be representative of perturbations of the proximity test signal at the cross-polarized antennas.

Abstract: A hidden chamber detector includes a linear frequency modulated continuous wave (LFMCW) radar, a synthetic aperture radar (SAR) imaging processor, and a time division multiple access (TDMA) multiple input multiple output (MIMO) antenna array, including a plurality of transmitting and receiving (Tx-Rx) antenna pairs. A Tx-Rx antenna pair is selected, in a time division manner, as a Tx antenna and an Rx antenna for the LFMCW radar. The LFMCW radar is configured to transmit an illumination signal, receive an echo signal, convert the echo signal to a baseband signal, collect baseband samples, and send the collected samples to the SAR imaging processor. The SAR imaging processor is configured to receive the collected samples, collect structure/configuration of the antenna array and scanning information, and form an SAR image based on the collected samples, the structure/configuration of the antenna array, and the scanning information.

Abstract: A radar antenna calibration method includes: forming a detection matrix from signals detected by an arrangement of receive antennas in response to chirps transmitted by an arrangement of transmit antennas, the detection matrix having multiple rows corresponding to the chirps, multiple columns corresponding to a signal sample, and multiple planes corresponding the receive antennas; deriving a range matrix by performing a frequency transform on a portion of each row of the detection matrix; extracting a slice of the range matrix, with different rows of the slice being associated with different chirps and with different receive antennas; deriving a velocity matrix from the extracted slice by performing a frequency transform on a portion of each column of the extracted slice; analyzing the velocity matrix to determine a current peak width; and adjusting, based on the current peak width, phase shifts associated with one or more of the receive antennas.

Abstract: A load balancing method for cellular communication systems and communication systems in general is described where beam steering antenna systems on the client or user side of the communication link are used to optimize load balancing among the base stations or nodes. A system controller containing an algorithm is implemented to control the radiation modes from the client or user devices to assign the client or user devices to the various base stations or nodes and to dynamically vary the network load across the cellular or communication system.

Abstract: Systems and methods are provided for a digital beamformed phased array feed. The system may include a radome configured to allow electromagnetic waves to propagate; a multi-band software defined antenna array tile; a power and clock management subsystem configured to manage power and time of operation; a thermal management subsystem configured to dissipate heat generated by the multi-band software defined antenna array tile; and an enclosure assembly. The multi-band software defined antenna array tile may include a plurality of coupled dipole array antenna elements; a plurality of frequency converters; and a plurality of digital beamformers.

Abstract: Presented herein are systems and methods for automatically evaluating detection accuracy of dynamic objects by equipment under test, comprising receiving a first record generated by an evaluated equipment under test and a second record generated by a validated reference equipment both deployed in a vehicle, the first record comprising a plurality of attributes of dynamic object(s) detected by the evaluated equipment and the second record comprising a plurality of attributes of dynamic object(s) detected by the reference equipment, correlating between dynamic object(s) detected by both the evaluated equipment and the reference equipment according to matching spatial and temporal attributes of the dynamic object(s) in the first record and in the second record, analyzing at least some of the attributes of the respective dynamic object in the first record compared to the second record, and outputting an indication of differences identified between the first record and the second record.

Abstract: A method and apparatus detects and estimates geo-observables of navigation signals employing civil formats with repeating baseband signal components, i.e., “pilot signals,” including true GNSS signals generated by satellite vehicles (SV's) or ground beacons (pseudolites), and malicious GNSS signals, e.g., spoofers and repeaters. Multi-subband symbol-rate synchronous channelization can exploit the full substantive bandwidth of the GNSS signals with managed complexity in each subband. Spatial/polarization receivers can be provided to remove interference and geolocate non-GNSS jamming sources, as well as targeted GNSS spoofers that emulate GNSS signals. This can provide time-to-first-fix (TTFF) over much smaller time intervals than existing GNSS methods; can operate in the presence of signals with much wider disparity in received power than existing techniques; and can operate in the presence of arbitrary multipath.

Abstract: Method and device for radar transmission and reception by dynamic change of polarization notably for the implementation of interleaved radar modes are provided.

Abstract: Example embodiments present radar units capable of operating in multiple polarizations. An example radar unit may include a set of transmission antennas and a set of reception antennas. Particularly, the transmission antennas may each be configured to transmit radar signals that radiate in one or more of four potential polarizations. The four polarizations can correspond to horizontal linear, vertical linear and slanted polarizations at approximately positive forty-five degrees and negative forty-five degrees from the horizontal plane. As such, the reception antennas of the radar unit may each be configured to receive reflected radar signals that are radiating in one of the four potential polarizations. The radar unit may further include an amplifier configured to cause one or multiple transmission antennas to selectively transmit between two or more of the four polarization channels.

Abstract: One of a transmitting array antenna and a receiving array antenna includes a first antenna group and a second antenna group. The first antenna group includes one or more first antenna elements of which the phase centers of the antenna elements are laid out at each first layout spacing following a first axis direction, and a shared antenna element. The second antenna group includes a plurality of second antenna elements and the one shared antenna element, and the phase centers of the antenna elements are laid out in two columns at each second layout spacing following a second axis direction that is different from the first axis direction. The phase centers of the antenna elements included in each of the two columns differ from each other regarding position in the second axis direction.

Abstract: A signal processing device, includes: an azimuth estimation unit configured to estimate an arrival azimuth of a radio wave based on a reception signal of plural antennas; an estimated reception signal calculation unit configured to calculate an estimated reception signal based on an estimation result of the arrival azimuth, for comparison with the reception signal; a residual signal calculation unit configured to calculate a residual signal which is a difference between the reception signal and the estimated reception signal; and a determination unit configured to determine whether the estimation result of the arrival azimuth is correct based on the residual signal.

Abstract: A method is provided for commodity management. The method generates, using a Dynamic Boltzmann Machine (DyBM), a future mean prediction and a future standard deviation prediction of a financial time-series dataset for a commodity. The method measures, using Hellinger Distance (HD), an accuracy of the future mean prediction and the future standard deviation prediction. The method combines the future mean prediction and the future standard deviation prediction with the Hellinger Distance to determine a DyBM trustworthy prediction time period in which predictions by the DyBM, including the future mean prediction and the future standard deviation prediction, are deemed trustworthy. The method selectively performs an action relating to an ownership of the commodity based on at least one of the future mean prediction and the future standard deviation prediction, responsive to the future mean prediction and the future standard deviation prediction being generated during the DyBM trustworthy prediction time period.

Abstract: A super resolution radar system, the radar system including: at least one antenna; transmission electronics; receiving electronics; and receiving computing electronics, where the transmission electronics is structured to transmit a first electromagnetic wave having an Orbital Angular Momentum wave-front using the antenna, where the transmission electronics is structured to transmit a second electromagnetic wave having a no Orbital Angular Momentum wave-front using a first portion of the antenna, where the receiving electronics is structured to form a first signal from a first return wave of the first electromagnetic wave, where the receiving electronics is structured to form a second signal from a second return wave of the second electromagnetic wave, and where the receiving computing electronics is structured to subtract the first signal from the second signal.

Abstract: The present system and method allow for accurate estimation of angle and angle rate for a target using a slewing antenna. These issues are accounted for by using a special form of non-coherent integration. An extension of the non-coherent integration may be used to estimate the target's angle rates. This technique can also be expanded to determine whether a target is in the main lobe or in a side lobe in one or two directions.

Abstract: The present disclosure provides a two-dimensional antenna system. The two-dimensional antenna system includes a transmitting antenna array and a receiving antenna array. The transmitting antenna array includes one or more circularly polarized transmitting antennas having a first direction of rotation. The receiving antenna array includes two or more first circularly polarized receiving antennas having a second direction of rotation arranged in a first direction, and two or more second circularly polarized receiving antennas having the second direction of rotation arranged in a second direction. The first direction is perpendicular to the second direction, and the first direction of rotation is opposite to the second direction of rotation.

Abstract: A radar antenna calibration method includes: forming a detection matrix from signals detected by an arrangement of receive antennas in response to chirps transmitted by an arrangement of transmit antennas, the detection matrix having multiple rows corresponding to the chirps, multiple columns corresponding to a signal sample, and multiple planes corresponding the receive antennas; deriving a range matrix by performing a frequency transform on a portion of each row of the detection matrix; extracting a slice of the range matrix, with different rows of the slice being associated with different chirps and with different receive antennas; deriving a velocity matrix from the extracted slice by performing a frequency transform on a portion of each column of the extracted slice; analyzing the velocity matrix to determine a current peak width; and adjusting, based on the current peak width, phase shifts associated with one or more of the receive antennas.

Abstract: Beamformers and beamforming methods are disclosed which involve diagonal loading (regularization). Features may include the automatic determination of the regularization parameter using a linearly constrained minimum power (LCMP) bounded perturbation regularization (BPR) approach.

Abstract: A method for active neutralization of the effect of the vibrations of a rotary-wing aircraft for a monostatic Doppler radar includes a first step of measuring and temporally extrapolating the vibration modes at the transmitting-receiving radar antenna, using a 3-axis vibration sensor, fixed to the antenna and near the phase centre of the antenna; then a second step of estimating the expected movements of the transmitting-receiving antenna or of the first transmitting antenna and the second receiving antenna; then a third step of compensating the expected movements of the transmission radar antenna in the transmission chain or in the reception chain of the radar transmitter, wherein the projection of the movement vector of the phase centre O on an aiming direction is calculated to determine the value of the compensation phase shift to be applied.

Abstract: A system and method for providing wireless data communication between a wireless communication system in an aircraft and a stationary communication server outside the aircraft are disclosed. The wireless communication system includes a plurality of antennas, and a router in the aircraft configured to transmit and receive wireless data communication to and from a stationary communication server outside the aircraft through at least one ground base station via at least one of the plurality of antennas. The plurality of antennas includes at least one omnidirectional antenna and at least one directional antenna. The router includes a control unit configured to restrict the wireless data communication to solely occur through the at least one directional antenna the when the current altitude of the aircraft is determined to be above a predefined altitude threshold value.

Abstract: A method of operating a radar system includes transmitting a plurality of transmitted radio frequency (RF) signals by a plurality of directional antennas. The plurality of directional antennas is disposed on a planar surface of a substrate. Each of the plurality of antennas is in a fixed orientation and position on the planar surface. A respective individual coverage of each of the plurality of directional antennas is less than 360°. A combined coverage of the plurality of transmitted RF signals completely covers a 360° region surrounding the radar system. The method also includes receiving a reflected RF signal by a directional antenna of the plurality of directional antennas.

Abstract: One of a transmitting array antenna and a receiving array antenna includes a first antenna group and a second antenna group. The first antenna group includes one or more first antenna elements of which the phase centers of the antenna elements are laid out at each first layout spacing following a first axis direction, and a shared antenna element. The second antenna group includes a plurality of second antenna elements and the one shared antenna element, and the phase centers of the antenna elements are laid out in two columns at each second layout spacing following a second axis direction that is different from the first axis direction. The phase centers of the antenna elements included in each of the two columns differ from each other regarding position in the second axis direction.

Abstract: A radar system with angle error determination function and method thereof are provided. The system includes a camera device, a radar device, a calculation module, and an angle calibration module. The camera device captures a surveillance image of a surveillance area. The radar device sends a radar signal toward the surveillance area. The calculation module, according to the surveillance image, acquires an image angle of an object with respect to the vehicle in the surveillance area. Also, the calculation module acquires a radar angle of the object with respect to the vehicle which is produced according to a reflection signal generated when the radar signal meets the object. The angle calibration module, by referring to the image angle, correspondingly calibrates the radar angle. Therefore, the radar angle is immediately calibrated.

Abstract: Monopulse radar apparatus is disclosed. The apparatus comprises a digital processor and an antenna having a plurality of receive channels through which signals received by the antenna are passed to the processor. Each receive channel includes an analogue to digital converter, and the processor is arranged to calculate sum and difference signals from the signals received through each receive channel. The processor is also arranged such that, in the event that a malfunction is detected in one of the plurality of receive channels, compensated sum and difference signals are calculated by the processor using the signals from the remaining, functioning receive channels.

Abstract: A mainlobe detection process can include a number of tests that are performed to define when the monopulse antenna system will transition from open loop scanning to closed loop scanning and then to tracking. A hybrid tracking technique is also provided which adaptively discovers and corrects for phase alignment error. Magnitude-only tracking can be performed initially to locate the nulls in the azimuth and elevation ratios and to identify the magnitudes of these ratios at these nulls. Phase tracking can be then performed. During phase tracking, phase corrections can be repeatedly applied to the azimuth and elevation difference channels to correct any phase error that may exist. During this process, the magnitudes of the ratios can be used to determine how the phase corrections should be adjusted. Once the hybrid tracking process is complete, the monopulse antenna system is properly phase-aligned and phase tracking will be correctly employed.

Abstract: Methods, apparatus, systems and articles of manufacture are disclosed for distributed, multi-node, low frequency radar systems for degraded visual environments. An example system includes a transmitter to transmit a radar signal. The example system includes a distributed network of radar receivers to receive the radar signal at each receiver. The example system includes a processor to determine a first range and a first angular position of a background point based on return time, wherein the first range and the first angular position are included in first data; determine a second range and a second angular position of the background point based on doppler shift, wherein the second range and the second angular position are included in second data; determine a refined range and a refined angular position, wherein the refined range and refined angular position are included in third data, and generate a radar map based on third data.

Abstract: An enhanced vision method or a weather radar system can be used with an aircraft and includes an antenna and a control circuit. The control circuit is configured to provide radar beams via the antenna toward external surroundings and is configured to receive radar returns. The control circuit is configured to process a collection of radar measurements from the radar returns, wherein each of the radar measurements is associated with a location determined using an antenna position, an antenna attitude, a beam sharpening angle, and a range. The radar measurements are processed to determine power density per grid cell associated with the power and location of the radar measurements, and the power density per grid cell is used to provide an image associated with the power and location of the radar measurements.