Sub-band processing of synthetic aperture sonar data

High frequency synthetic aperture sonar systems require demanding tolerances in motion errors and medium phase stability. This article proposes a new method that mitigates the problems associated with small wavelength related errors. By dividing the received signal bandwidths in to several smaller ones and conjugate complex multiplying them, a new signal is obtained with longer effective wavelength, thus reducing the impact of motion errors and medium phase fluctuations.