A preprocessing technique for synthetic radar images. An embodiment of a method for preprocessing synthetic aperture radar images includes: receiving range-compressed radar data generated from raw radar image data on-board a satellite or an airborne vehicle; generating a preliminary SAR image by performing a pre-focusing on the range-compressed radar data; extracting image subsectors from the preliminary SAR image; transmitting the extracted image subsectors to an on-ground portion; reconstructing the range-compressed radar data pertaining to the extracted image subsectors; and making the range-compressed radar data pertaining to the extracted image subsectors available for a Nominal synthetic aperture radar processor, wherein the Nominal synthetic aperture radar processor is configured to generate a focused SAR image having a nominal value of image resolution that is higher than the resolution of the preliminary SAR image.

Systems, methods, tangible non-transitory computer-readable media, and devices associated with sensor output segmentation are provided. For example, sensor data can be accessed. The sensor data can include sensor data returns representative of an environment detected by a sensor across the sensor's field of view. Each sensor data return can be associated with a respective bin of a plurality of bins corresponding to the field of view of the sensor. Each bin can correspond to a different portion of the sensor's field of view. Channels can be generated for each of the plurality of bins and can include data indicative of a range and an azimuth associated with a sensor data return associated with each bin. Furthermore, a semantic segment of a portion of the sensor data can be generated by inputting the channels for each bin into a machine-learned segmentation model trained to generate an output including the semantic segment.

A vehicle radar apparatus and a method of controlling the vehicle radar apparatus, including a transmission array antenna that radiates a radar signal for forward detection; a reception array antenna that operates at N (N is an integer greater than zero) reception channels for receiving the radar signal that is radiated by the transmission array antenna, reflects from a target, and returns; an azimuth angle estimation unit that estimates an azimuth angle of the target using each non-offset reception channel of the N reception channels; and an elevation angle estimation unit that estimates an elevation angle of the target in a diagonal direction in which each non-offset channel of the N reception channels is tilted with respect to an azimuth angle of an offset reception channel thereof.

A radar image processing device performs determination of a pixel including a ghost image and changes the value of the pixel which is determined to include the ghost image on a radar image the focus of which has been changed.

The present disclosure relates to an apparatus and method for synthetically making an ultra-wide imaging bandwidth in millimeter-wave frequencies, resulting in improved image resolutions to values previously unattained. The synthetic approach sums up a number of available sub-bands to build an unavailable ultra-wideband system. Each sub-band contains a transceiver unit which is optimized for operation within that specific sub-band. The number and position of the sub-bands can be adjusted to cover any frequency range as required for the specific application.

A method for space-variance correction imaging of BiSAR includes: motion parameters corresponding to a target point in an equivalent monostatic mode are calculated using a first motion trajectory, a second motion trajectory and an imaging parameter for focusing a radar echo signal, the target point at least including a center point of an imaging scene; azimuth Doppler center bias correction is performed on the radar echo signal by using the motion parameters corresponding to the center point; uniform and residual range cell migration correction is performed on a corrected signal, range blocking is performed, and range space-variance phase errors are corrected block by block; azimuth blocking is performed, and a corresponding number of filters are constructed for filtering processing; and inverse Doppler center bias correction is further performed to obtain a final imaging result graph.

A synthetic aperture radar (SAR) is operable in an interrogation mode and in an imaging mode, the imaging mode entered in response to determining a response to interrogation pulses have been received from a ground terminal and position information specifying a ground location has been received from the ground terminal. A ground terminal is operable to receive interrogation pulses transmitted by a SAR, transmit responses, and transmit position information to cause the SAR to enter a imaging mode. The ground terminal receives first and subsequent pulses from the SAR where subsequent pulses include backscatter and are encoded. The ground terminal generates a range line by range compression. If the SAR is a multi-band SAR the transmitted pulses can be in two or more frequency bands, and subsequent pulses in one frequency band can include encoded returns from pulses transmitted in a different frequency band.

A computing machine receives a real synthetic aperture radar (SAR) image including one or more targets. The real SAR image is one of a plurality of real SAR images in a training set. The computing machine generates, for the real SAR image, a model-based target shadow background (TSB) image using a three-dimensional (3D) model of the target. The computing machine generates, for the real SAR image and using an auto-encoder engine, an auto-encoder-generated TSB image using an artificial neural network (ANN). The computing machine computes, using a discriminator engine, an image difference between the auto-encoder-generated TSB image and the model-based TSB image. The computing machine adjusts weights in the auto-encoder engine based on the computed image difference.

The present invention relates to the technical fields of optical imaging, microwave imaging, radar detection, sonar, ultrasonic imaging, and target detection, imaging identification and wireless communication based on media such as sound, light and electricity, and in particular, to a fast imaging method suitable for passive imaging and active imaging and application of the fast imaging method in the above fields. According to the method provided by the present invention, image field distribution corresponding to a target is achieved based on a lens imaging principle, in combination with an electromagnetic field theory, according to a target signal received by an antenna array, through the amplitude and phase weighting of a unit signal and by using an efficient parallel algorithm. The method provided by the present invention has the advantages of capability of being compatible with passive imaging and holographic imaging, good imaging effect, small operation amount, low hardware cost, high imaging speed and suitability for long-distance imaging, and can be widely applied in the fields of optical imaging, microwave imaging, radar detection, sonar, ultrasonic imaging, and target detection, imaging identification and wireless communication based on media such as sound, light and electricity.

Synthetic aperture radar transmit and receive antenna systems and methods of transmitting and receiving radar signals are disclosed. In one embodiment, a transmit and receive antenna system includes a transmit antenna array configured to transmit a plurality of radio frequency transmit signals, the transmit antenna array including a plurality of patch antenna elements mounted to a printed circuit board, each patch antenna element belonging to a subarray, and one or more power amplifiers, each power amplifier feeding a subarray of the patch antenna elements, and a reflectarray receive antenna configured to receive radio frequency signals including a plurality of reflectarray antenna elements mounted to a printed circuit board, at least one antenna feed configured to receive radio frequency signals reflected from the plurality of reflectarray antenna elements, and at least one low noise amplifier electrically connected to the at least one antenna feed.