Patent ID: 7714768
Filing Date: 2010-05-11
Classification: G01S

Abstract:
1. A non-statistical method for compressing and decompressing complex SAR data derived from a reflected energy, comprising: receiving SAR data in complex floating point form at sixty-four bits per sample, the data in a two dimensional table corresponding to Range and Azimuth, each sample corresponding to a Range and Azimuth location; selecting a first FFT to provide a target ratio of pixel spacing to resolution; selecting a second FFT smaller than the first FFT; zero-padding the SAR data to fill the second FFT; encoding the SAR data through the second FFT to provide a plurality of pixels, each pixel having a Range and Azimuth location set, for each Range and Azimuth location set there is an associate Phase and Magnitude of the reflected energy, each pixel having sixty-four bits, thirty-two bits for a logarithm of Magnitude and thirty-two bits for an arctangent of Phase; converting the thirty-two bit logarithm Magnitude to a first eight-bit fixed value and the thirty-two bit arctangent of Phase to a second eight-bit fixed value; transferring the first and second eight-bit fixed values to a remote location; converting the first and second eight-bit values back to the thirty-two bit logarithm Magnitude and thirty-two bit arctangent of Phase; inverting the second FFT transformation at the remote location to restore the SAR data from the Magnitude and Phase as restored SAR data; zero-padding the restored SAR data to fill the first FFT; and transforming the zero-padded restored SAR data to provide a data set of points with the target ratio of pixel spacing to resolution.