Research on plane wave decomposition with transverse oscillations for sonar imaging

The purpose of this paper is to introduce a new beamforming method for sonar imaging, which is proposed based on the plane wave decomposition combine with back-propagation method and with transverse oscillations. This method was initially proposed for ultrasound Doppler imaging using transverse oscillations in linear geometry. The plane wave decomposition theory is used to decompose in different directions an acoustic field into a set of plane waves. By back-propagating the plane waves to the transducer array and after summing up all the back-propagated signals, we get one signal for each transducer. Transverse oscillations (TO) technique produces sonar images featuring oscillations in both spatial dimensions. This is natural for axial direction but necessitates specific beamforming for transverse direction. Thus this paper is aiming at improve sonar imaging quality in terms of lateral direction and adapting it to sonar sector scanning.