The invention concerns a method (1) to detect deformations of, and/or damages to, structures permanently arranged on the earth's surface. In particular, said method (1) comprises: acquiring (11) georeferencing data indicative of geographical reference positions of predefined points of interest of a given structure to be monitored permanently arranged on the earth's surface, wherein said predefined points of interest are representative of a 3D geometry of the given structure without deformations and damages; acquiring (12) a SAR image of an area of the earth's surface where the given structure is arranged, wherein said SAR image is associated with a given reference coordinate system; transforming (13) the geographical reference positions of the predefined points of interest into corresponding expected positions in the given reference coordinate system associated with the acquired SAR image so as to carry out a reprojection of the 3D geometry of the given structure without deformations and damages on the acquired SAR image; identifying (14) in the acquired SAR image the predefined points of interest of the given structure; determining (15) actual positions in the given reference coordinate system associated with the acquired SAR image of the predefined points of interest identified in said SAR image; making a comparison (16) between the expected positions of the predefined points of interest and the corresponding actual positions in the acquired SAR image; and detecting (17) one or more deformations of, and/or one or more damages to, said given structure on the basis of the comparison made.

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 navigation apparatus includes an image capturing device, template database, correlation device, evaluation device, and output interface. The image capturing device can create a radar image of a surround, the template database configured to provide at least one template substantially matched to the radar image and containing at least one geo-referenced landmark, the at least one geo-referenced landmark being geo-referenced by at least one geo-coordinate. The correlation device can correlate the at least one geo-referenced landmark in the at least one template with the radar image and provide the at least one geo-coordinate belonging to the at least one geo-referenced landmark. The evaluation device can determine a position of the navigation apparatus from the at least one geo-coordinate of the at least one geo-referenced landmark and from a setting of the image capturing device. The output interface is configured to provide the determined position.

Method and device for radar transmission and reception by dynamic change of polarization notably for the implementation of interleaved radar modes are provided. A radar transmission-reception method and a device for implementing this method, the method alternatively implementing two modes of operation, a short range mode exploiting short pulses and a long range mode exploiting modulated long pulses, the method consisting, for each mode, in: producing two synchronous radiofrequency (RF) transmission signals having between them a phase-shift θ of controllable given value; radiating two radiofrequency waves, each corresponding to one of the transmission RF signals produced, by means of two colocated radiating sources each having a given polarization axis; handling the reception of the backscattered radiofrequency signals picked up by each of the radiating sources, and delivering two radiofrequency (RF) reception signals each corresponding to a radiofrequency signal picked up by one of the radiating sources, a phase-shift θ′ being applied between the two signals delivered, θ′ being able to be determined as being equal to θ.

A signal processor 2 is configured so as to compensate for a peak shift of the distance between an SAR sensor 1 and a target, the peak shift occurring in the received signal subjected to range compression performed by an image reconstruction processing unit 14 due to a movement of the SAR sensor 1 during a time period until a reflected wave of a pulse signal is received by the SAR sensor 1 after the pulse signal is emitted from the SAR sensor 1. As a result, even when the SAR sensor 1 moves, an SAR image in which no azimuth ambiguity occurs can be reconstructed.

A synthetic aperture radar (SAR) system is disclosed. The SAR comprises a memory, a convolutional neural network (CNN), a machine-readable medium on the memory, and a machine-readable medium on the memory. The machine-readable medium storing instructions that, when executed by the CNN, cause the SAR system to perform operations. The operation comprises: receiving range profile data associated with observed views of a scene; concatenating the range profile data with a template range profile data of the scene; and estimating registration parameters associated with the range profile data relative to the template range profile data to determine a deviation from the template range profile data.

Disclosed is a synthetic aperture radar (SAR) system for target recognition with complex range profile. The SAR system comprising a memory, a recurrent neural network (RNN), a multi-layer linear network in signal communication the RNN, and a machine-readable medium on the memory. The machine-readable medium is configured to store instructions that, when executed by the RNN, cause the SAR system to perform various operations. The various operation comprise: receiving raw SAR data associated with observed views of a scene, wherein the raw SAR data comprises information captured via the SAR system; radio frequency (RF) preprocessing the received raw SAR data to produce a processed raw SAR data; converting the processed raw SAR data to a complex SAR range profile data; processing the complex SAR range profile data with the RNN having RNN states; and mapping the RNN states to a target class with the multi-layer linear network.

The present invention concerns a method for performing SAR acquisitions, which comprises performing, in a time division fashion, SAR acquisitions of areas of a swath of earth's surface by means of a SAR system carried by an air or space platform; wherein performing SAR acquisitions in a time division fashion includes contemporaneously acquiring, in each pulse repetition interval, a plurality of areas of the swath that are separated in azimuth; and wherein the areas acquired in T successive pulse repetition intervals form an azimuth-continuous portion of said swath, T being an integer greater than one.

A method for detecting a horizontally buried linear object is provided, the horizontally buried linear object having a longitudinal extension. The method comprises moving, with a flying platform comprising a radar for synthetic aperture radar, SAR, vertical imaging, along a trajectory corresponding to a synthetic aperture. The method further comprises transmitting and receiving radar signals while moving along the trajectory corresponding to the synthetic aperture. The method also comprises forming a SAR image based on collected data representing radar signal reflections received from the ground. The method additionally comprises detecting one or more features in the formed SAR image relating to the horizontally buried linear object. Said trajectory is oriented in a direction substantially perpendicular to an expected orientation of the longitudinal extension of the horizontally buried object and traversing the horizontally buried object.

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