International Journal of Engineering and Technology

Imaging the sea floor using high precision sonar is at the stage where the efficiency and robustness are of concern. Synthetic aperture sonar (SAS) has the appealing property of range and frequency independent spatial resolution. SAS data’s are more challenging to process than the conventional counterparts, because the towfish is more complicated and usually non stationary. Time domain algorithms can handle general sonar, but they are inefficient. Several frequency domain algorithms have been modified to handle a limited number of SAS cases. In the present work, a closed form expression for the stripmap geometry model is mathematically derived and analyzed from the high resolution SAS imaging point of view. Further, we discussed the processing method for SAS data and proposed a chirp scaling algorithm (CSA). We have focused on the application of CSA processor that is based on the use of the Fourier transforms. The simulation results validate the analysis and the feasibility of this algorithm.