A synthetic aperture radar image analysis system 20 includes: a phase correlation determination means 21 which determines a strength of the phase correlation between a plurality of pixels in an image selected from among a plurality of images on the basis of the plurality of images that have been photographed by a synthetic aperture radar and show the same point; a shape determination means 22 which determines a degree of similarity between the shape of the distribution of the plurality of pixels and an object shape indicated by geospatial information; and an association means 23 which associates the plurality of pixels with the object on the basis of the determined strength of the phase correlation and the determined degree of similarity.

A method and a device for separating echo signals of STWE SAR in elevation are provided. The method includes that: aliasing echo signals of multiple sub-swaths are received; for a target sub-swath of the multiple sub-swaths, multiple sub-beams associated with the target sub-swath are generated, the multiple sub-beams pointing to different directions of the target sub-swath respectively, and a null of each of the multiple sub-beams being used for deep nulling suppression on echo signals of sub-swaths except the target sub-swath; and the aliasing echo signals are processed based on the multiple sub-beams and multiple nulls corresponding to the multiple sub-beams to generate a target echo signal of the target sub-swath.

A synthetic aperture radar (SAR) system generates an image of a first swath. The SAR includes at least one SAR antenna, at least one SAR processor and at least one SAR transceiver. In operation the SAR defines a first beam to illuminate the first swath and one or more second beams to illuminate area(s) of ambiguity associated with the first beam. The SAR transmits a pulse via the first beam and receives backscatter energy. The SAR generates a first signal associated with the first beam and one or more second signals associated with the second beam(s). The second signal(s) are combined with determined complex vector(s), generating ambiguity signal(s) and the ambiguity signals are combined with the first signal to generate an image associated with the first swath.

A method and a system for detection and synthetic aperture (SA) imaging of a target are disclosed. The method may include illuminating a scene with a search signal transmitted from a moving platform, receiving a search return signal from a target present in the scene, and estimating, from the search return signal, the range and the angular location of the target. The method may also include generating an SA transmission signal and a local oscillator (LO) signal with a time delay therebetween based on the estimated range, and illuminating the scene with the SA transmission signal pointed along an imaging direction based on the estimated angular location of the target. The method may further include receiving an SA return signal from the target, mixing the SA return signal with the LO signal to generate SA signal data, and generating an SA image of the target from the SA signal data.

A synthetic aperture radar method for remote sensing of the surface of the Earth by means of a radar device on a flying object moving in an azimuth direction above the surface of the Earth, wherein the radar device includes an array of antenna elements for transmitting radar pulses in a transmitting operation and for receiving radar echoes of these radar pulses reflected at the surface of the Earth in a receiving operation. A calibration mode is carried out in which the transmission of the radar pulses in the transmitting operation is carried out with a pulse repetition rate such that only echo signals of a single radar echo are received by all antenna elements of the array at the same point in time in the receiving operation; in the receiving operation, the echo signals are recorded in a plurality of receiving channels, wherein a different antenna element is assigned to a respective receiving channel, and in the respective receiving channel the echo signals received by the assigned antenna element are digitized and directly stored, thereby obtaining digitized radar data; the digitized radar data are further processed to determine a set of calibrated parameters of the radar device for the SAR operating mode for obtaining SAR images.

The presently disclosed subject matter includes a UAV surveillance system and method which enables quick and convenient activation of an on-board radar (e.g. in SAR or GMTI mode) without having predefined suitable flight instructions. It enables ad-hoc operation of radar data acquisition devices allowing to switch from EO data acquisition to radar data acquisition or activate a radar side-by-side with an EO sensing device.

A synthetic aperture radar (SAR) generates concurrent first radar pulses in first frequency channels. The SAR transmits, and receives returns of, the concurrent first radar pulses by first antenna feeds that form first beams in the first frequency channels and that are directed to respective first subswaths of a swath on the Earth separated by subswath gaps. The SAR generates concurrent second radar pulses in second frequency channels. The SAR transmits, and receives returns of, the concurrent second radar pulses by second antenna feeds configured to form second beams in the second frequency channels and that are directed to respective second subswaths of the swath on the Earth and that coincide with the subswath gaps. The SAR processes the returns of the first radar pulses from the first subswaths and the returns of the second radar pulses from the second subswaths to form a SAR image contiguous across the swath.

A side-looking High Resolution Wide Swath Synthetic Aperture Radar, HRWS-SAR, system comprising an antenna array and a beamforming network. The antenna array comprises a plurality of antenna elements to transmit and receive electromagnetic waves. The beamforming network includes a plurality of true time delay lines, TTDLs connected to a plurality of phase shifters. Each phase shifter is connected to a respective one of the plurality of antenna elements. The beamforming network engages with the transmit antenna array to transmit the electromagnetic waves by performing beamsteering across a swath using a pulse. The pulse has a chirped waveform and a transmit pulse duration. Beamsteering is performed based on an increasing or decreasing frequency of the chirped waveform over the transmit pulse duration. The beamforming network engages with the antenna array to receive, during a receive time window, echoes corresponding to the electromagnetic waves reflected by or from the swath.

A synthetic aperture radar (SAR) system and method of operation advantageously implements dynamic self-cueing or autonomous cueing of successive high-resolution SAR data collection based on previously collected wide-swath SAR data, for instance without the intervention of ground-based resources. For example, target detection may be performed on-board a spaceborne or airborne SAR platform using wide-swath SAR data acquired via a first beam at a first frequency band, the first beam pointed at a first angle relative to an along-track direction. Subsequent activities are cued by the platform based on the previously collected wide-swath SAR data. For instance, the SAR platform may cue subsequent acquisition of SAR data via a second beam at a second frequency band, the second beam pointed at a second angle relative to an along-track direction. The SAR platform may advantageously employ a multi-band SAR antenna.

A Spotlight SAR imaging mode is implemented by a synthetic aperture radar (SAR) system in which an SAR controller intentionally spoils a transmit beam of the SAR antenna to form a spoiled transmit beam. The SAR system transmits pulses using the spoiled transmit beam, divides the SAR antenna into a plurality of azimuth apertures, receives received pulses by the SAR antenna using a number M of multiple receive beams, processes data received by each of the number M of multiple receive beams to generate a number M of sub-images by the SAR processor; and coherently combines two or more of the number M of sub-images to form a Spotlight image. Thus, a multi-aperture antenna comprises multiple azimuth apertures (i.e., a sub apertures), each formed from one or more azimuth phase centers. The sub-apertures can be independent from one another. The sub-apertures can keep a target illuminated by the beam for a longer time than conventional Stripmap mode, for example. The sub-apertures can be combined in processing to form a high resolution image, with high image quality.