Patent classifications
G01S13/9076
Synthetic aperture radar target modeling
For synthetic aperture radar (SAR) pixel vectoring, a method identifies target features of a target from a plurality of SAR signals. The method further classifies the target from the target features. In addition, the method enhances a pixel vector of the target in response to the target classification.
GROUND CONTROL POINT DEVICE AND SAR DISPLACEMENT MEASURING SYSTEM
A ground control point device includes an SAR wave reflector configured to receive an SAR wave incident from an SAR in an incident direction and to reflect the SAR wave in the incident direction; a GNSS receiver configured to receive a GNSS wave to generate, based on the GNSS wave, time information and positional information indicative of a position of a control point; an SAR wave receiver configured to receive the SAR wave; and a control point data generator/transmitter configured to generate control point data obtained by associating the positional information when the SAR receiver receives the SAR wave with a time instant of reception of the SAR wave that is determined based on the time information, and to transmit the control point data to outside.
Terrestrial imaging using multi-polarization Synthetic Aperture Radar
An embodiment of a method for processing synthetic aperture radar (SAR) image data includes acquiring a multi-polarization SAR image of a terrestrial region, pre-processing the SAR image to remove or reduce radiometric and geometric errors, and separating the SAR image into a plurality of channels, each channel representing an image associated with a different polarization mode. The method also includes calculating a characteristic of the region for each polarization channel, acquiring ground data and estimating the characteristic of the region based on the ground data, estimating a correlation of the calculated characteristic for each polarization channel with the estimated characteristic based on the ground data, selecting one or more polarization channels having a correlation exceeding a selected value, and generating a SAR image including only the selected polarization channels based on the comparison.
Systems and methods for performing synthetic aperture radar imaging using superchirps
Synthetic aperture radar (SAR) imaging systems that transmit repeated waveforms based upon pseudonoise sequences to generate SAR imaging data in accordance with various embodiments of the invention are disclosed. A synthetic aperture radar in accordance with one embodiment of the invention includes: a transmitter configured to transmit superchirps, where the superchirp is generated by convolving a kernel with a pseudonoise modulated impulse sequence having a flat power spectrum; a receiver configured to receive backscatters of transmitted superchirps and digitize the received backscatters; and signal processing circuitry configured to perform matched filtering on digitized backscatters.
System and method of detecting underground gas leakage
A system and a method may detect underground water or gas leakage. The method may include receiving a first scan of an area including an underground gas pipe at a first polarization, the first scan including first microwave reflections of the area at a wavelength range of 3.8 cm to 1.3 m; receiving additional data, filtering electromagnetic noise from the first scan using the additional data; creating a water roughness map based on typical roughness values of a set of types of water sources and the filtered first scan; identifying one or more water accumulations at one or more locations along the gas pipe using the water roughness map and the filtered first scan and calculating the water content at the one or more locations along the gas pipe based on the identified one or more water accumulations.
RETRIEVAL METHOD AND APPARATUS FOR RESERVOIR WATER STORAGE
A retrieval method and a retrieval apparatus for reservoir water storage. The retrieval method includes the following steps. A synthetic aperture radar (SAR) image sequence of a target local waters in a target reservoir is acquired. A water area sequence of the target local waters is determined according to the SAR image sequence. A first relationship between a water level of the target reservoir and a water area of the target local waters of the target reservoir is obtained. The water area sequence is converted into a target water level sequence according to the first relationship. And a water storage sequence of the target reservoir is obtained according to a water level-water storage relationship curve and the target water level sequence.
Subsurface imaging radar
A method and system for obtaining SAR images with reduced or eliminated surface clutter to detect subsurface targets, the method comprising the following steps:selecting a first frequency and an incidence angle for the radar signal such that the ratio of surface backscattering to subsurface target backscattering is significantly larger for vertical polarization than for horizontalobtaining vertically and horizontally polarized SAR images based on the same SAR path exploiting the selected first frequency and viewing angleweighting and differencing the vertically and horizontally polarized SAR images so that the surface backscattering completely cancels between the two images and only the combination of the target backscattering components remains.
Radar device
A radar device includes: an aperture surface including element antennas and phase shifters; an antenna phase control unit for calculating phase amounts based on a beam orientation direction and a rotation angle of the aperture surface; an antenna driving control unit for setting a rotation angle to a rotation mechanism; a signal processing unit for detecting a target with the use of the radar receiver, setting at least one of the rotation angle of the aperture surface or the beam orientation direction in the antenna driving control unit and the antenna phase control unit, and calculating the level of competing cluttering with the use of an antenna pattern, to thereby determine propriety of the rotation angle; and a pattern calculating unit for calculating the antenna pattern from the rotation angle of the aperture surface and from the beam orientation direction.
SPACEBORNE SYNTHETIC APERTURE RADAR SYSTEM AND METHOD
The present invention relates to an advanced spaceborne Synthetic Aperture Radar (SAR) system and method that can provide high resolution measurements of the Earth or planetary surface, overcoming limitations in conventional SAR systems, and reduce development costs. The present invention utilizes advanced and innovative techniques, such as software defined waveforms, digital beamforming (DBF) and reconfigurable hardware, to provide radar capabilities not possible with conventional radar instruments, while reducing the radar development cost. The SAR system architecture employs a modular, low power, lightweight design approach to meet stringent spaceborne radar instrument requirements. Thus, the present invention can enable feasible Earth and planetary missions that address a vast number survey goals, including the measurement of ecosystem structure and extent, surface and sub-surface topography, subsurface stratigraphy, soil freeze-thaw, ice sheet composition and extent, glacier depth, and surface water, among many others.
METHOD AND DEVICE FOR SUPPRESSING RANGE AMBIGUITY IN SYNTHETIC APERTURE RADAR
In a method and device for suppressing range ambiguity in Synthetic Aperture Radar (SAR), azimuth transmission-phase modulation is performed respectively, using a preset rule for phase modulation, on pulse signal data transmitted on a channel of Horizontal (H) polarization and pulse signal data transmitted on a channel of Vertical (V) polarization. Full polarimetric echo data corresponding to the transmission-phase modulated pulse signal data transmitted on the channel of H polarization and the transmission-phase modulated pulse signal data transmitted on the channel of V polarization are acquired. Azimuth phase demodulation is performed on the full polarimetric echo data using a preset rule for phase demodulation. Echo data are acquired by filtering out, using a preset azimuth filter, range-ambiguity energy from the phase demodulated full polarimetric echo data.