Patent ID: 7183965

Claim:
A radar generates a search mode synthetic aperture image of a patch from a sequence of periodic pulse returns reflected from said patch, said radar having a motion along a path, said motion at a range from said patch, said path positioned at an azimuth angle from said patch, said radar comprising: an analog to digital converter for converting said pulse returns from said patch into a digital stream, said digital stream descriptive of said pulse returns as a function of said range and said azimuth angle; a computer for computing: an azimuth interpolation and range interpolation for generating an interpolated sequence having samples oriented in range and azimuth frequency with uniform spacing; a range compression of said interpolated sequence of periodic pulse returns to obtain a compressed sequence; an azimuth deskew of said compressed sequence to obtain a deskewed sequence; an autofocus and pulse restore of said deskew sequence to obtain a focused sequence; an azimuth reskew of said focused sequence to obtain a reskewed sequence; a gain phase equalization of said reskewed sequence to obtain an equalized sequence; a summing of a first linear phase for applying a fractional sample shift in range frequency to said equalized sequence to obtain a shifted sequence; a range FFT and Along Track IFFT of said shifted sequence to obtain a domain changed sequence; a summing of a second linear phase to said domain changed sequence; a CT FFT of said domain changed sequence to obtain an image of said patch.