Abstract
This paper discusses the basic performance and problems of Synthetic Aperture Sonar (SAS) along with the experimental results of a prototype SAS. The concept of SAS and its basic performance are described first. Then theoretical resolution is compared with that of the experimental results. The experimental results for spherical targets indicate that both range-track and along-track resolution satisfy the theoretical values. Another experiment presents that SAS is robust and is not sensitive to reverberation. The paper also describes problems that need to be solved if the SAS is to be of practical use. One such problem is restriction due to the Pulse Repetition Frequency (PRF) and another is image degradation caused by unwanted platform motion. A computed image where the PRF condition is not satisfied shows many ghost targets due to phase errors. The other experimental results indicate that the sway motion, which shifts the platform along a transmitting direction, causes serious degradation.
