Visualisation of wave propagation inside the target at two time points showing how the complex shape of the target affects the propagation paths. The wave, originating from outside of the lower left corner of the images, enters the target at two interfaces: first at the left body of the target and later at the head region in which the second wavefront is ahead of the first, which is travelling more slowly inside the target (left image). The scattered wavefronts can also eventually mix (right) due to a reflection back from the interior walls, producing constructive and destructive interference in addition to multipath effects of direct scattering.