Abstract: A radar system with on-system calibration for cross-coupling and gain/phase variations includes capabilities for radar detection and correction for system impairments to improve detection performance. The radar system is equipped with pluralities of transmit antennas and pluralities of receive antennas. The radar system uses a series of calibration measurements of a known object to estimate the system impairments. A correction is then applied to the beamforming weights to mitigate the effect of these impairments on radar detection. The estimation and correction requires no external measurement equipment and can be computed on the radar system itself.

Abstract: A method for determining wave height by means of a radar carried by an aircraft, the method implementing the following steps: a first step of pointing the antenna of the radar; a second step of determining the clutter acquisition plan according to the altitude of the aircraft; a third step of determining, for each clutter zone defined by the acquisition plan, two Doppler parameters PARA1 and PARA2 characterising the zone as a whole; a fourth step of calculating the average values of the parameters PARA1 and PARA2 over all of the zones in question; and a fifth step of estimating the wave height from the averages of the parameters PARA1 and PARA2. The wave height estimated in this way is transmitted to the aircraft and used to determine the conditions for the water landing of the aircraft.

Abstract: Determining a target's range profiles is an important issue for coastal surveillance radars because it can give us the knowledge about the target, for example, target's type, target's structure and its length along radial direction. Some modern radars nowaday are equipped with the feature of target's range profile extraction, but the results are not accurate due to limitations in processing algorithms. The invention “system and method of determining target's range profiles for coastal surveillance radars” solves the above problem in the direction of proposing a system of technical solutions and associated algorithm improvements.

Abstract: Exemplary aspects are directed to circuitry that assesses and differentiates a set of targeted data and updates a high-level bin with a numerical value indicating the number of data elements that compared successfully with a predefined value range defined for each bin. A cumulative sum of the high-level bins may then be calculated. Following, a target threshold may be compared to the cumulative sum at each bin and then providing an indication upon discovering a cumulative sum exceeding the threshold. The targeted data may be further refined by changing (through circuitry or other intervention) the predefined range values and then reprocessing the targeted data.

Abstract: Provided are methods of using electromagnetic waves for detecting metal and/or dielectric objects. Methods include directing microwave and/or mm wave radiation in a predetermined direction using a transmission apparatus, including a transmission element; receiving radiation from an entity resulting from the transmitted radiation using a detection apparatus; and generating one or more detection signals in the frequency domain using the detection apparatus. Methods may include operating a controller, wherein operating the controller includes causing the transmitted radiation to be swept over a predetermined range of frequencies, performing a transform operation on the detection signal(s) to generate one or more transformed signals in the time domain, and determining, from one or more features of the transformed signal, one or more dimensions of a metallic or dielectric object upon which the transmitted radiation is incident.

Abstract: Techniques are discussed for determining reflected returns in radar sensor data. In some instances, pairs of radar returns may be compared to one another. For example, a reflection point may be determined from a first position of a first radar return and a second position of a second radar return. Additional data, e.g., sensor data and/or map data, may be used to determine the presence of objects in the environment. The first return or the second return may be a reflected return if an object is disposed at the reflection point. In some instances, a vehicle, such as an autonomous vehicle, may be controlled at the exclusion of information from reflected returns.

Abstract: A radar fill level measurement device for determining a fill level of a medium is provided, including a transmitter configured to transmit a transmission signal towards the medium; a receiver configured to receive a reception signal reflected by the medium; and a controller configured to determine the fill level of the medium based on the reception signal and based on at least one evaluation parameter, the radar fill level measurement device being configured to vary a transmitting power of the transmission signal, the controller being further configured to determine a current transmitting power of the transmission signal, and the controller being further configured to vary, based on the determined current transmitting power, a value of the at least one evaluation parameter and/or at least one measurement signal that correlates with the reception signal, such that the fill level is determined taking into account the transmitting power.

Abstract: Provided are a direct wave suppression method and system for a microwave imaging system. The method includes a series of filtering operations, such as conversion from a frequency domain to a time domain, filtering, conversion from the time domain to the frequency domain, and cancellation subtraction, on an echo signal set composed of echo signals obtained by a vertical linear array antenna at all the equivalent antenna collection positions thereof.

Abstract: A system is provided, including: a radar sensor configured to transmit and receive a radar signal from a person; a depth camera configured to receive a depth image of the person; one or more processors communicative with memory having stored thereon computer program code configured when executed by the one or more processors to cause the one or more processors to perform a method comprising: detect the person; determine depth information relating to the person using the depth image; determine a correlation between the depth information of the person and the radar signal received from the person; and in response to the correlation not within a range of expected values, generating an alert. The depth information may be a volume or surface area of the person.

Abstract: Objects are examined using electric fields (3201, 3202, 3203, 3204, 3205, 3206, 3207) created by a first set of electrodes (1101 to 1108). A selected electrode (1108) from the first set is energized as a transmitter and a different selected electrode (1107) is monitored as a receiver, to establish a capacitively coupled pair of electrodes defining a coupling operation. Two electrodes are (1107, 1108) are selected that are separated by a first distance as a first coupled pair during a first coupling operation. During a second coupling operation, two electrodes (1106, 1108) are selected that are separated by a second distance, where the second distance is larger then the first distance. The first coupled pair and the second coupled pair both include a first electrode in common (1108).

Abstract: In order to accurately identify a target object, a signal processor is provided, which includes an extracting module configured to extract, from echo sample sequences, a plurality of samples caused by the target object as a partial sample sequence, a characteristic amount calculating module configured to calculate a characteristic of the partial sample sequence as a characteristic amount, a memory configured to store a plurality of type-based data that are data as comparison targets of the characteristic amount and correspond to types from which the target object is identified, and an identifying module configured to compare the characteristic amount with each of the plurality of type-based data and, based on the comparison result, identify the target object corresponding to the partial sample sequence for which the characteristic amount is calculated.

Abstract: A method and device for generating an image, the method including: generating an active radar image of an object; displaying the active radar image in a first representation on a display of a handheld screening device; detecting a movement of the handheld screening device; generating a second representation of the displayed radar image based on the detected movement.

Abstract: The present disclosure relates to a method and device for detecting concealed dangerous objects in microwave images. The method includes: simultaneously processes multiple adjacent microwave images, obtains edge images of a single image by using two methods for each image, obtains dangerous-object edges of the single image by edge fitting operation, obtains a rough dangerous-object contour by performing a registration operation and a second edge fitting operation on the dangerous-object edges of the multiple images, and performs a regional-binarization operation and a filtering on the rough dangerous-object contour to obtain a second dangerous-object area. The present disclosure has high detection accuracy and calculation efficiency.

Abstract: A detection method for a given mission comprises at least: one phase of analysing the environment using a waveform chosen beforehand, the signals acquired with this waveform being analysed by processing means in order to deduce therefrom environmental characteristics; and one phase of generating an optimal detection wave depending on the environmental characteristics and characteristics of the mission.

Abstract: Embodiments described herein provide for the improved detection of target(s) in the vicinity of cluttered environments such as wind farms, and for the reduction of false alarms resulting from wind turbines and other complex structures in such environments. Maximum amplitude readings of all non-zero Doppler frequency bins are determined for each resolution cell under test during a dwell and used to determine an aggregate threshold value. In one embodiment, the aggregate threshold value and an existing threshold value are compared and the higher value applied. A tracking sample period and a transition state delay are introduced to determine when the aggregate threshold value for each resolution cell under test should be updated.

Abstract: Methods and systems are provided that inventory a plot of trees based on data including one or more (e.g., all) of radar images of the plot, spectral images of the plot (e.g., high resolution images taken by satellite), other data (e.g., elevation, slope, aspect), and actual tree survey data physically collected about the plot and/or another plot having similar characteristics. Although the actual tree survey data collected is typically less than the amount of actual survey data used by prior approaches, the present systems and methods are still capable of inventorying the entire plot with a high degree of confidence (e.g., at least 95% confidence).

Abstract: A measurement apparatus outputs from a first antenna pair transmission signals (St11) and (St12) whose phase difference (??1) changes over time. A target object simultaneously receives the transmission signals (St11) and (St12) from a target-side antenna and returns to the measurement apparatus information (D?) according to the positional relationship between the target object and the measurement apparatus determined from a reception signal (Sr1). The measurement apparatus outputs from a second antenna pair transmission signals (St21) and (St22) whose phase difference (??2) changes over time. The target object simultaneously receives the transmission signals (St21) and (St22) from the target-side antenna and returns to the measurement apparatus the information (D?) corresponding to the positional relationship between the target object and the measurement apparatus determined from a reception signal (Sr2).

Abstract: A system for providing an estimate of far-field radar cross-section (RCS) measurements of an aircraft. The system includes a plurality of automatic guided vehicles (AGV) each including a robot arm and a radar unit selectively mounted thereto and being interchangeable with a camera. Each AGV includes an AGV controller for controlling the robot arm, the radar unit and the camera so as to cause the radar unit to provide the near-field RCS measurements or the camera to provide images of the aircraft. The system further includes a real time signature diagnostic sub-system (SDS-RT) responsive to the near-field RCS measurement signals from the radar units and the images from the cameras in real time, and an SDS controller responsive to re-configured near-field RCS measurement signals and images from the SDS-RT and configuring the near-field RCS measurement signals and the images into the estimate of the far-field RCS measurements of the aircraft.

Abstract: A handheld screening device including: an antenna array including a plurality of antennas; an input mechanism to select an operation mode; and a controller to determine a group of antennas of the plurality of antennas, wherein the number of antennas in the group is based on the selected operation mode, and to control the group of antennas to emit electromagnetic waves. A corresponding method operates the handheld screening device.

Abstract: Embodiments of the invention are directed to detecting an underwater object from an air-based system. The air-based system is associated with at least one controller. A broadband acousto-optic signal detection device is associated with the air-based platform. The broadband acousto-optic signal detection device is configured to emit a laser beam at an underwater object. The laser beam terminates at the underwater object and reflects back as a return laser beam. The broadband acousto-optic signal detection device is configured to detect and receive the return laser beam.

Abstract: The invention is related to a method and a signal generator for generating a sea clutter simulation signal used as an input signal for a radar system. The method comprises the steps of: modeling of gravity waves using a physical simulation of a sea surface; modeling of capillary waves using stochastic processes; and adding the modeled capillary waves to the modeled gravity waves.

Abstract: A testing method or apparatus utilizes filter banks to measure time varying or dynamic harmonic distortion or intermodulation distortion from a device. With a stairstep or arbitrary signal and filter banks, Nth order harmonic and or intermodulation distortion is measured via the filter banks at different offsets provided by an arbitrary low frequency signal. An amplifier with crossover distortion will show increased harmonic and or intermodulation distortion near the zero crossing while providing less distortion in other portions of the transfer curve of the amplifier. One or more distortion signals from the device (e.g., audio device) may be measured for a phase and or frequency modulation effect.

Abstract: An apparatus for efficient, precise and accurate measurement of the frequency, amplitude, and phase of a single input tone frequency and/or multiple separable input tone frequencies. Tone separability can be achieved by proper selection of the parameter N, the sample length of the DFT/FFT. Application of the invention includes but is not limited to test and measurement, tone interference removal, and communications systems, where precise and accurate measurement of tonal parameters is needed.

Abstract: A method and system generates a three-dimensional (3D) image by first acquiring data from a scene using multiple parallel baselines and multiple different pulse repetition frequencies (PRF), wherein the multiple baselines are arranged in a hyperplane. Then, a 3D compressive sensing reconstruction procedure is applied to the data to generate the 3D image corresponding to the scene.

Abstract: In a general aspect, motion detected using wireless signals is categorized. In some aspects, frequency response signals are obtained. The frequency response signals are based on wireless signals that were transmitted through a space and received at a wireless sensor device over a time period. Values of a statistical parameter are determined for the time period, with the statistical parameter for the time period being based on a function applied to frequency components of the frequency response signals over the time period. A category of motion that occurred in the space during the time period is identified based on the values of the statistical parameter.

Abstract: Systems and methods for providing personal radar, object presence detection, and object localization are provided. Multiple devices that perform high-resolution ranging can be operated to perform radar in an area, detect objects and motion of objects in the area, and generate a virtual steerable antenna.

Abstract: A survey system including a multibeam echo sounder having a single projector array and a single hydrophone array constructs a multi-component message for ensonifying multiple fans and deconstructs a corresponding message echo for use in analyzing the returns from each fan.

Abstract: Embodiments include an apparatus comprising a frequency selective electromagnetic receiver and a signal analyzing module. The frequency selective electromagnetic receiver is configured to receive a reradiating electromagnetic signal resulting from a cavity induced modulation phenomenon occurring within cavit(ies). The signal analyzing module is configured to: determine a power spectral density of the reradiating electromagnetic signal. Frequencies are observed at which the amplitude modulation of the power spectral density peaks. A cavity length is determined employing the frequencies of the power spectral density peaks.

Abstract: A method of controlling a radar system by: receiving a radar return signal from a target and generating a range-Doppler target image signature of the target; selecting a spectral line within the range-Doppler target image signature from a modulation feature on the target which includes an effective point scatterer; providing a range profile for the spectral line; obtaining a reference range profile of a reference point scatterer; and determining a difference between a power at a range shorter than a peak corresponding to the modulation feature in the range profile and a power at a corresponding range of the reference range profile. The method may further include controlling provision of the range-Doppler target image signature based on the difference.

Abstract: A method detects misconfiguration of a wireless network which wastes battery power in mobile devices within a location area of the network. A data collection agent installed in a wireless device records and reports idle-mode handovers. An analytics circuit reads RF measurements and locations from these reports to suggest where handover zones may be optimized or IRAT cell resection parameters are defective. A mobile device may self-tune battery consumption by determining its individual location areas of high battery consumption; desensitizing itself to cell signal strength instability; and increasing its tenacity to a most recently used cell.

Abstract: A spectral feature extracting engine, chirp detecting engine, and target classifying engine with corresponding method, system, and computer product are provided. Given a “noisy” signal having multiplicative and additive noise, the spectral feature extracting engine extracts spectral features from the noisy signal in the form of a spectral detection density. The extraction includes identifying an initial detection by comparing the spectral content of a subject time-frequency slice with an initial detection threshold calculated from a set of time-frequency slices, and determining the spectral detection density as a function of a number of identified initial detections and number of compared time-frequency slices. Based on the spectral detection density of the noisy signal, the chirp detecting engine detects multiple channel-induced and target-induced chirps present in the noisy signal and the target classifying engine classifies a target from the noisy signal.

Abstract: A radar sensor and a method of detecting an object by using the same are provided. The method includes: receiving at least one radar signal reflected from the object; converting the received at least one radar signal to at least one signal in a frequency domain; accumulating the converted at least one signal for a predetermined time and extracting at least one feature from the accumulated at least one signal; and identifying the object by comparing the extracted at least one feature with at least one reference value stored in a database.

Abstract: A method and apparatus are provided for detecting a RADAR signal. RADAR channel data in a frequency range is received, where the frequency range is divided into a plurality of equally wide channels. The received RADAR channel data is digitally processed and analyzed to identify a signal in the RADAR channel data in the frequency range. The frequency range is advanced to a next channel of the plurality of channels, where the frequency range of the next channel of the plurality of channels is nonsequential with the frequency range of the first channel. The steps of receiving, processing, and analyzing are repeated for the next channel of the plurality of channels.

Abstract: A system for suppressing clutter in a radar system is provided. The system includes an antenna configured to receive radar signals containing clutter and a digital receiver adapted to convert the radar signals received by the radar arrays to complex I/Q samples. These I/Q samples are provided to a Doppler filter bank comprising a plurality of Doppler filters for filtering the pulse compressed data into Doppler bins representative of range values according to Doppler frequency. The system further includes at least one processor for comparing the output of each of the plurality of Doppler filters types to respective background clutter maps, and identifying the Doppler filter which outputs the radar return signal with the greatest magnitude over the clutter map. Once identified, target detection operations may be performed on the output of the identified Doppler filter.

Abstract: An apparatus for measuring the orientation of the longitudinal axis of a cavity comprising a signal receiver, a signal processor and analyzer and a cavity axis orientation analyzer. The signal receiver receives a reflected signal resulting from an interaction of multi-frequency irradiating signal(s) with at least one cavity. The irradiating signal may include an electromagnetic or acoustic signal above a cavity dependent cutoff frequency with a randomized or deterministic spectral component. The signal analyzer computes a power spectral density of the reflected signal. The local maxima of the power spectral density are identified and used to determine the cavity longitudinal axis orientation. The cavity may be the bore of a weapon.

Abstract: The present disclosure relates to the field of pulse compression in signal processing, and more particularly, to systems and methods for the synthesis of waveforms for suppressing sidelobes and sidebands using a combination of time and spectral control. More specifically, the present disclosure relates to a set of waveform symbols which can be used to maximize use of disaggregated grey-space spectrum, adapt to changing spectral condition, and maintain or enhance data rates relative to standard binary phase-shift keying (BPSK) under normal conditions.

Abstract: A frequency reference device that includes a frequency reference generation unit to generate a frequency reference signal based on an absorption line of a gas.

Abstract: An instrument (100) is provided according to an embodiment of the invention. The instrument (100) includes an interface (101) configured to receive a Doppler measurement signal and a processing system (112) coupled to the interface (101) and receiving the Doppler measurement signal. The processing system (112) is configured to generate a two-sided velocity spectrum including a plurality of discrete frequency bins from the Doppler measurement signal, with the two-sided velocity spectrum distinguishing spectral elements, and process one or more velocity spectrum bin pairs against a plurality of local gate thresholds, with the one or more velocity spectrum bin pairs being substantially symmetrically located about one or more carrier wave bins and wherein each velocity spectrum bin pair is processed against a corresponding local gate threshold of the plurality of local gate thresholds.

Abstract: In a radar apparatus, a peak extractor performs frequency analysis on a beat signal to obtain a frequency spectrum for each of first and second detection modes based on the beat signal for a corresponding one of the first and second detection modes. The peak extractor extracts a plurality of first peak-signal components from the frequency spectrum obtained for the first detection mode, and a plurality of second peak-signal components from the frequency spectrum obtained for the second detection mode. A determiner compares each of the plurality of first peak-signal components with a corresponding one of the plurality of second peak-signal components to deter mine whether a noise is included in the beat signal according to a result of the comparison.

Abstract: A method of synthetic imaging comprising the steps of: emitting a first electromagnetic signal having a first frequency from a first radiation source, emitting at least one second electromagnetic signal having a second frequency from a second radiation source, wherein the first and second frequencies are different from each other, substantially simultaneously receiving the first signal and the second signal with a first receiver, substantially simultaneously receiving the first signal and the second signal with at least one second receiver, arranging an object on the path of at least one electromagnetic signal between the radiation sources and the receivers, wherein the signals are reflected by the object before they meet the receivers, and computing an image of the object from the signals received by the receivers and a device for practicing the method.

Abstract: A method and system for detecting the presence of subsurface objects within a medium is provided. In some embodiments, the imaging and detection system operates in a multistatic mode to collect radar return signals generated by an array of transceiver antenna pairs that is positioned across the surface and that travels down the surface. The imaging and detection system pre-processes the return signal to suppress certain undesirable effects. The imaging and detection system then generates synthetic aperture radar images from real aperture radar images generated from the pre-processed return signal. The imaging and detection system then post-processes the synthetic aperture radar images to improve detection of subsurface objects. The imaging and detection system identifies peaks in the energy levels of the post-processed image frame, which indicates the presence of a subsurface object.

Abstract: A method and system for detecting the presence of subsurface objects within a medium is provided. In some embodiments, the imaging and detection system operates in a multistatic mode to collect radar return signals generated by an array of transceiver antenna pairs that is positioned across the surface and that travels down the surface. The imaging and detection system pre-processes the return signal to suppress certain undesirable effects. The imaging and detection system then generates synthetic aperture radar images from real aperture radar images generated from the pre-processed return signal. The imaging and detection system then post-processes the synthetic aperture radar images to improve detection of subsurface objects. The imaging and detection system identifies peaks in the energy levels of the post-processed image frame, which indicates the presence of a subsurface object.

Abstract: An electronic scanning radar apparatus mounted on a moving object includes a receiving unit including a plurality of antennas receiving a received wave arriving from a target having reflected a transmitted wave, a beat signal generating unit generating a beat signal from the transmitted wave and the received wave, a frequency resolving unit resolving the beat signal in beat frequencies and to calculate complex data based on the beat signal resolved for each beat frequency, and an azimuth detecting unit calculating a direction of arrival of the received wave based on original complex data calculated based on the beat signal, wherein the azimuth detecting unit includes a data extending unit generating extended complex data by extending the number of data based on the original complex data, and a first computation processing unit calculating the direction of arrival of the received wave based on the extended complex data.

Abstract: In a method for frequency matching in an FMCW radar sensor, a plurality of frequencies, which are derived on various modulation ramps, and which respectively are shown by the radar sensor in a d-v space as geometrical locations, represent possible combinations of a distance d and a speed v of the respective object. In order to identify the objects located on the various modulation ramps, coincidences between the geometrical locations which belong to frequencies derived on various modulation ramps are searched for. The search for coincidences is initially restricted in a first step to a subspace of the d-v space, and in a subsequent step, the search is extended to other regions of the d-v space, while suppressing the frequencies that are associated with the objects found in the first step.

Abstract: In an environment inspection mode of a calibration system, a radar device executes a signal analysis process to calculate an eigenvalue ratio of each comparison eigenvalue. The eigenvalue ratio has a small value when a pair of eigenvalues corresponding to arrival radar waves has a strong correlation. On the other hand, the eigenvalue ratio has a large value when the eigenvalue ratio is calculated between an eigenvalue and thermal noise. When there is no eigenvalue which is not more than a reference threshold value, the radar device indicates a notice that the current environment is suitable for the calibration of the radar device. On the other hand, when there is presence of at least one eigenvalue of not more than the reference threshold value, the radar device indicates a notice that the current environment is unsuitable for the calibration of the radar device.

Abstract: There is provided a radar apparatus for detecting a target. A detection signal generating unit generates detection signals of the target based on transmission and reception waves of antennas. A detection signal processing unit performs frequency analysis on the detection signals to extract signal components of the target, and performs a predetermined process on the signal components to calculate at least one of a distance to the target, a relative speed to the target, and an orientation of the target. The detection signal generating unit includes a filter unit for giving changes to the detection signals in a frequency bandwidth higher than Nyquist frequency which is a half a sampling frequency. The detection signal processing unit acquires the signal components from the detection signals to which the filter unit gives the changes to determine whether the signal components are generated by replication due to the Nyquist frequency.

Abstract: Systems and methods for automatically determining a noise threshold are provided. In one implementation, a system comprises: an antenna configured to gather data about a surrounding environment; a processing unit configured to remove samples representing target data from the gathered data; to estimate the noise floor from the gathered data with the removed target data; and to determine a noise threshold from the estimated noise floor; and a memory device configured to store the estimated noise floor.

Abstract: According to one embodiment, a calculating of a weight includes which is calculating a covariance matrix by applying a process (Post-Doppler process) of selecting a plurality of banks after execution of a Doppler filter process to a specified number of pulses of the received signal, and extracting a plurality of arbitrary bank parts from among the plurality of selected banks which are used for the calculation of the covariance matrix, and calculating a plurality of weights on a phase and an amplitude, from a matrix of the plurality of extracted bank parts.

Abstract: An electronic scanning type radar device mounted on a moving body includes: a transmission unit transmitting a transmission wave; a reception unit comprising a plurality of antennas receiving a reflection wave of the transmission wave from a target; a beat signal generation unit generating a beat signal from the transmission wave and the reflection wave; a frequency resolution processing unit frequency computing a complex number data; a target detection unit detecting an existence of the target; a correlation matrix computation unit computing a correlation matrix from each of a complex number data of a detected beat frequency; a target consolidation processing unit linking the target in a present detection cycle and a past detection cycle; a correlation matrix filtering unit generating an averaged correlation matrix by weighted averaging a correlation matrix of a target in the present detection cycle and a correlation matrix of a related target in the past detection cycle; and a direction detection unit compu

Abstract: Methods are described for radar detection of persons wearing wires using radar spectra data including the vertical polarization (VV) radar cross section and the horizontal polarization (HH) radar cross section for a person. In one embodiment, the ratio of the vertical polarization (VV) radar cross section to the horizontal polarization (HH) radar cross section for a person is compared to a detection threshold to determine whether the person is wearing wires. In another embodiment, the absolute difference of the vertical polarization (VV) radar cross section and the horizontal polarization (HH) radar cross section for a person is compared to a detection threshold to determine whether the person is wearing wires. To reduce false positives, other additional indicators, such as speed of movement, and or visual features of the person, can be used to further narrow a person suspected of wearing wires.