The invention discloses a
satellite-borne
synthetic aperture radar (SAR) imaging method based on Doppler cubic term
estimation. The method comprises the following steps of: 1, reading echo
simulation data of a
satellite-borne SAR sliding beam bunching mode; 2,
processing the echo
simulation data, and thus obtaining a two-dimensional
frequency domain signal; 3, setting a Doppler cubic term initial value, an iteration threshold and an iteration step length; 4, acquiring a
signal which is subjected to distance compensation; 5, acquiring an imaging result
signal; 6, acquiring the maximum value and position of a one-dimensional signal; 7, acquiring a left first
side lobe peak of a one-dimensional signal
main lobe; 8, acquiring a right first
side lobe peak of the one-dimensional signal
main lobe; 9, acquiring an absolute value of difference between the left first
side lobe peak and the right first side lobe peak; and 10, comparing the absolute value with a threshold Th, and judging according to a comparison result. The method has the advantages that a high-accuracy Doppler cubic term is obtained by using an iteration method, phase errors brought by the conventional slope
distance model under the condition of
high resolution are compensated, and a
satellite-borne SAR focusing image is obtained, so the effectiveness and accuracy of the method are verified.