Fig. 4

There are multiple consecutive pulses in every scanline, 3 of them are displayed in the top row. Second row represents the corresponding received pulses. The received tissue (linear scatterer) signals are combined by adding the two half amplitude signals and subtracting the full amplitude signal. For tissue, the echoes cancel one another, leading to tissue suppression. The third row represents corresponding signals received from microbubbles (nonlinear scatterers). The shape of the full height pulse is different from the half height pulse resulting in a significant “nonlinear” signal remaining after the sum of the received signals from the two half height pulses are subtracted from the full height pulse (Permission to publish images granted by Philips Healthcare)