Interferometric bathymetric sidescan sonar is much like standard sidescan sonar, illuminating the bottom with a narrow, fan-shaped beam, and recording the reflected echoes as a uniformly sampled time series. A bathymetric sidescan however receives the echoes on two or more parallel arrays, per side. The arrays are sampled independently, so that any plane-wave striking them will produce a phase difference indicative of the arrival angle. With the travel time of the echoes, the arrival angled calculated from phase difference, the array mount angles and the towfish attitude, one can calculate reflector distance and depth.
To learn more about Interferometric Sidescan sonars supported by OIC products, click here.