G01S13/9023

SATELLITE-FORMATION-BASED REMOTE SENSING SYSTEM AND CONSTELLATION SYSTEM
20220283295 · 2022-09-08 ·

The present invention relates a remote sensing system, or particularly a satellite-formation-based remote sensing system, wherein comprising: a master satellite provided with an SAR system as a payload thereof, a first concomitant satellite, and a second concomitant satellite, wherein the first concomitant satellite and the second concomitant satellite fly around the master satellite, and the master satellite is located on major axes of motion trajectories of the first concomitant satellite and the second concomitant satellite, so as to define a first spatial baseline and a second spatial baseline that have an identical cross-track baseline component. The present invention enables high-precision, wide-range, three-dimensional imaging based on the satellite-formation, while acquires spatiotemporal features of variation of a ground region according to the synchronization in terms of time, frequency, and space.

Satellite tomography of rain and motion via synthetic aperture

The system and method represents a high-resolution, three-dimensional, multi-static precipitation RADAR approach that employs agile microsatellites, in formation and remotely coupled, via a new high-precision, ultra-low power, remote timing synchronization technology. This system and method uses multi-static RADAR interferometric methods implemented via a microsatellite formation to synthesize an effectively large (e.g., 15 m) aperture to provide about 1 km horizontal resolution and about 125 m vertical resolution in the Ku-band.

SYNTHETIC APERTURE RADAR SIGNAL PROCESSING DEVICE AND SIGNAL PROCESSING METHOD
20220221577 · 2022-07-14 · ·

The signal processing device includes an interference processing unit which generates an interferogram from a plurality of SAR images, a coherence calculation unit which calculates coherence of the SAR images, a singular point processing unit which performs an operation for resolving singular points in the interferogram, a phase unwrapping unit which executes a phase unwrapping process using operation result of the singular point processing unit, and an SBAS analysis unit which performs displacement analysis by SBAS, using processing result of the phase unwrapping unit.

Systems and methods for automotive synthetic aperture radar

Embodiments are disclosed that for synthetic aperture radar (SAR) systems and methods. Front-end circuitry transmits radar signals, receives return radar signals, and outputs digital radar data. FFT circuits process the digital radar data without zero-padding to generate FFT data corresponding to oversampled pixel range values. A processor further processes the FFT data to generate radar pixel data representing a radar image. Further, the FFT circuits can interpolate the FFT data based upon pixel ranges using a streamlined range computation process. This process pre-computes x-axis components for pixels in common rows and y-axis components for pixels in common columns within the FFT data. For one embodiment, a navigation processor is coupled to a SAR system within a vehicle, receives the radar pixel data, and causes one or more actions to occur based upon the radar pixel data, such as an advanced driver assistance system function or an autonomous driving function.

SYSTEMS AND METHODS FOR FOREST CANOPY HEIGHT ESTIMATION
20220284605 · 2022-09-08 ·

Systems and methods of automating the generation of a correction of an estimate of an elevation of a digital elevation model (DEM) of the bare earth under forest canopy. The disclosed embodiments facilitate generation of a more accurate DEM in areas of canopy coverage (where the input X-band DSM cannot see the ground) to estimate both the canopy height and the associated DEM. In some embodiments, the result of computationally correcting an estimate of an original DEM is a modified DEM. The method of correcting an estimate of an original DEM utilizes a pair of P-band radar images, an original DEM overlapping the same scene as the P-band radar images, at least one common, uniquely-identifiable point in the P-band radar images, and a definition of a geographical area surrounding the common, uniquely identifiable point over which the elevation correction is applicable.

Vertical lift aircraft panels with embedded spiral antennas
11456537 · 2022-09-27 · ·

A system of spiral antennas is incorporated into aircraft body panels. The spiral antennas may be slot or printed material antennas, cavity backed for unidirectional communication, or open for bi-directional communication. The spiral antennas are operated in concert as a steerable array. The spiral antennas are utilized for various signal functions including ultra-wideband communications and electronic support measures interferometry.

Ground control point device and SAR displacement measuring system
11307303 · 2022-04-19 · ·

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.

SYSTEM USING A PRIORI TERRAIN HEIGHT DATA FOR INTERFEROMETRIC SYNTHETIC APERTURE RADAR (IFSAR) PHASE DISAMBIGUATION AND RELATED METHODS

A system may include a memory and a processor cooperating therewith to obtain geospatially registered first and second interferometric synthetic aperture radar (IFSAR) images of a geographic area having respective first and second actual grazing angles with a difference therebetween, and convert the first IFSAR image to a modified first IFSAR image having a modified first grazing angle based upon known terrain elevation data for the geographic area. The modified first grazing angle may be closer to the second actual grazing angle than the first actual grazing angle. The processor may further recover updated terrain elevation data for the geographic area based upon the modified first IFSAR image and the second IFSAR image.

Synthetic aperture radar signal analysis device, synthetic aperture radar signal analysis method, and synthetic aperture radar signal analysis program
11835619 · 2023-12-05 ·

A synthetic aperture radar signal analysis device 20 includes: an extraction unit 21 that extracts a stable reflection point from time-series data acquired through observation, by a synthetic aperture radar, of a region to be observed from a predetermined observing direction; a generation unit 22 that generates a cluster which is a collection of stable reflection points on the basis of the extracted stable reflection point corresponding to the predetermined observing direction; an association unit 23 that associates the generated cluster corresponding to the predetermined observing direction with a structure indicated by map data corresponding to the region to be observed; and a synthesis unit 24 that performs vector-synthesis of displacement rates for a plurality of the clusters each corresponding to the observing direction associated with the structure.

Land deformation measurement
11269072 · 2022-03-08 · ·

A method of measuring land deformation over time using interferograms derived from synthetic aperture radar data. The method includes: acquiring radar images covering an area at different points in time; deriving interferograms from pairs of the images, each interferogram measuring phase difference between pixels of a respective pair of images; for each pixel of the interferograms: determining an average coherence value over all of the interferograms; and if the average value is less than a threshold, determining an adjusted average coherence value equal to or above the threshold by excluding one or more of the interferograms below the threshold, provided the number of remaining interferograms is not less than a preset minimum number for each pixel of each interferogram for which the average or adjusted average coherence value is above the threshold, deriving vertical movement from the phase difference; and deriving the map of land deformation from the vertical movement.