Efficient digital signal processing algorithm for sonar imaging

An algorithm is presented which can be efficiently applied to a variety of sonar imaging modes including forward looking, side-looking and synthetic aperture sonar. The digital focused beamforming (DFB) algorithm for pixel based imaging utilises key attributes of both time and frequency domain techniques. DFB for forward looking imaging is described in detail and adaptation of the basic concept in application to the other imaging modes is outlined. Examples of both simulated and real images are presented.