Reduced wavenumber synthetic aperture
OwnerIra B. Ekhausinventor
Life of this patent
Estimating the term…
Abstract
A system for radiation imaging of objects within a target area utilizing echo signals from a target area such as a patch of seafloor or the anatomy of a body. Data is obtained by time domain measurements received at a plurality of transducers in either monostatic or bistatic mode. Using multidimensional interferometry and multidimensional Fourier transforms, the data is reconstructed in multiple temporal and spatial frequency domains with a unique reduced wavenumber characteristic that retains the resolution potential of a traditional synthetic aperture approach. The system is inherently robust in applications with significant transceiver motion and/or variations in the propagation characteristics of the surrounding medium.
Claims12
A target imaging method comprising:
- a) converting multi-frequency radiant energy echoes received at a plurality of locations from at least one target in a region into multi-dimensional digital echo signals with at least one temporal variable and at least one pair of spatial variables;
- b) performing a complex conjugate product on the digital echo signals to produce interferometric data;
- c) performing a multi-dimensional Fourier Transform on the interferometric data to produce intermediate data with at least one spectral variable and at least two wavenumber variables;
- d) phase correcting the intermediate data;
- e) performing an interpolation on the intermediate data to produce secondary data having at least three wavenumber variables;
- f) performing an inverse multi-dimensional Fourier Transform on the secondary data to produce spatial correlation data with at least one pair of spatial variables;
- and
- g) processing the spatial correlation data to produce final spatial image data corresponding to the at least one target by collapsing the correlation data of each pair of spatial data variables to one spatial variable.
A target imaging system comprising:
- a) means for converting multi-frequency radiant energy echoes received at a plurality of locations from at least one target in a region into multi-dimensional digital echo signals with at least one temporal variable and at least one pair of spatial variables;
- b) means for performing a complex conjugate product on the digital echo signals to produce interferometric data;
- c) means for performing a multi-dimensional Fourier Transform on the interferometric data to produce intermediate data with at least one spectral variable and at least two wavenumber variables;
- d) means for phase correcting the intermediate data;
- e) means for performing an interpolation on the intermediate data to produce secondary data having at least three wavenumber variables;
- f) means for performing an inverse multidimensional Fourier Transform on the secondary data to produce spatial correlation data with at least one pair of spatial variables;
- and
- g) means for processing the spatial correlation data to produce final spatial image data corresponding to the at least one target comprising means for collapsing the correlation data of each pair of spatial data variables to one spatial variable.
Dependencies are inferred from the claim text.