Synthetic aperture radar signal processing device and synthetic aperture radar signal processing program

A non-transitory computer readable storage medium having a synthetic aperture radar signal processing program in which processing steps of a synthetic aperture radar signal process performed by a computer (52) are described, said program comprising:

• a determination processing step (ST5) of determining whether an error between an predicted position of a moving platform at an observation time of a synthetic aperture radar (1) and a position of the moving platform at the observation time is within an allowable range, the synthetic aperture radar (1) being mounted on the moving platform, the position of the moving platform being indicated in measurement data of a motion sensor (4) which measures motion of the moving platform;
• a first calculation processing step (ST6) of calculating, when it is determined in the determination processing step (ST5) that the error is out of the allowable range, a distance from the moving platform to a pixel position in an observation target and a phase factor used for compensating for the error, the pixel position corresponding to the predicted position, said first calculation processing step (ST6) being performed by using the predicted position at the observation time and the measurement data;
• a second calculation processing step (ST7) of calculating, when it is determined in the determination processing step (ST5) that the error is within the allowable range, a distance to the pixel position and a phase factor used for compensating for the error by means of a computation method with lower accuracy than that of the first calculation processing step (ST6), said second calculation processing step (ST7) being performed by using the predicted position at the observation time and the measurement data;
• and
• an image reconstruction processing step (ST9) of reconstructing a synthetic aperture radar image by performing a backprojection process that uses the distance and the phase factor calculated in the first calculation processing step (ST6) or the second calculation processing step (ST7) and also uses observation data of the synthetic aperture radar (1) obtained at the observation time.