Abstract:
A system and method for discrimination and identification of a target including: receiving a radar return signal including target information and clutter information; determining a two-fold forward or forward-backward data matrix from the received signal, using a multi-dimensional folding (MDF) process; computing singular values of the two-fold forward or forward-backward data matrix; using the computed singular values to determine a noise power level of the radar return signal; determining the number of scatterers in the radar return signal according to a predetermined threshold value above the noise power; estimating complex Doppler and azimuth frequencies of each scatterer from the determined number of scatterers using the MDF process; determining dispersive scatterers and non-dispersive scatterers using the estimated Doppler and azimuth complex frequencies of each scatterer; and distinguishing the target information from the clutter information, according to the determined dispersive scatterers and non-dispersive scatterers.
Abstract:
A synthetic aperture radar imaging method that combines each radar return pulse with a sinusoid to reduce the radar return pulses to a baseband frequency and deskew each radar return pulse. It includes determining a maximum likelihood estimate (MLE) of residual motion parameters for a dominant scatterer on the ground relative to the airborne radar and correcting for errors in inertial navigation system measurements based on the MLE residual motion parameters. It includes convolving each radar return pulse with its corresponding radar transmission pulse to generate a range compressed image for each radar return pulse and generating a sub-band range profile image for each radar return pulse and its corresponding radar transmission pulse based on the corresponding range compressed image that has been corrected for residual motion. Performing bandwidth extrapolation on each sub-band and subsequently combining the three bands to produce an enhanced resolution image without grating lobes.
Abstract:
A synthetic aperture radar imaging method that combines each radar return pulse with a sinusoid to reduce the radar return pulses to a baseband frequency and deskew each radar return pulse. It includes determining a maximum likelihood estimate (MLE) of residual motion parameters for a dominant scatterer on the ground relative to the airborne radar and correcting for errors in inertial navigation system measurements based on the MLE residual motion parameters. It includes convolving each radar return pulse with its corresponding radar transmission pulse to generate a range compressed image for each radar return pulse and generating a sub-band range profile image for each radar return pulse and its corresponding radar transmission pulse based on the corresponding range compressed image that has been corrected for residual motion. Performing bandwidth extrapolation on each sub-band and subsequently combining the three bands to produce an enhanced resolution image without grating lobes.
Abstract:
Embodiments of a device and a frequency data extrapolator are generally described herein. The frequency data extrapolator may receive input frequency data mapped to a two-dimensional frequency grid. As an example, the input frequency data may be based on return signals received, at a sensor of the device, in response to pulsed transmissions of the sensor in a physical environment. Regions of the frequency grid may be classified as high fidelity or low fidelity. A group of basis rectangles may be determined within the high fidelity regions. A column-wise extrapolation matrix and a row-wise extrapolation matrix may be determined based on the input frequency data of the basis rectangles. The input frequency data of the high fidelity regions may be extrapolated to replace the input frequency data of the low fidelity regions.
Abstract:
Embodiments of a device and a frequency data extrapolator are generally described herein. The frequency data extrapolator may receive input frequency data mapped to a two-dimensional frequency grid. As an example, the input frequency data may be based on return signals received, at a sensor of the device, in response to pulsed transmissions of the sensor in a physical environment. Regions of the frequency grid may be classified as high fidelity or low fidelity. A group of basis rectangles may be determined within the high fidelity regions. A column-wise extrapolation matrix and a row-wise extrapolation matrix may be determined based on the input frequency data of the basis rectangles. The input frequency data of the high fidelity regions may be extrapolated to replace the input frequency data of the low fidelity regions.
Abstract:
A bistatic synthetic aperture radar (SAR) imaging system and method include: combining each radar return pulse from airborne radar platforms with a sinusoid; deskewing each reduced radar return pulse; estimating motion parameters based on a maximum likelihood estimation (MLE); performing MLE motion correction to generate motion-corrected radar return pulses; acquiring position and velocity estimates of the airborne radar platforms and scattering locations; defining bistatic range and velocity vectors; defining new bistatic range and velocity vectors in a new set of orthogonal axes; projecting vector distance differences between the radar scattering locations along the new set of orthogonal axes to generate new range and velocity measurements along the new set of orthogonal axes; converting the new range and velocity measurements to map Doppler frequency into cross-range; and forming a bistatic SAR image in range and cross-range based on cross-range extent derived from the Doppler frequency mapping.
Abstract:
Embodiments of synthetic aperture radar systems for mapping Doppler frequency to cross-range to form bistatic inverse synthetic radar images of airborne targets.
Abstract:
A system and method for discrimination and identification of a target including: receiving a radar return signal including target information and clutter information; determining a two-fold forward or forward-backward data matrix from the received signal, using a multi-dimensional folding (MDF) process; computing singular values of the two-fold forward or forward-backward data matrix; using the computed singular values to determine a noise power level of the radar return signal; determining the number of scatterers in the radar return signal according to a predetermined threshold value above the noise power; estimating complex Doppler and azimuth frequencies of each scatterer from the determined number of scatterers using the MDF process; determining dispersive scatterers and non-dispersive scatterers using the estimated Doppler and azimuth complex frequencies of each scatterer; and distinguishing the target information from the clutter information, according to the determined dispersive scatterers and non-dispersive scatterers,