  Photoacoustic imaging develops very fast in recent years due to its superior
performance in many preclinical and clinical applications. However, it is still
in a developing stage, and a lot of experiments have to be performed in a
simulation setting. To simulate photoacoustic imaging in a computer, k-Wave is
currently the most popular MATLAB toolbox. Lots of research groups choose
k-Wave toolbox to perform the forward projection process, which also can be
described as forward model. However, by solving complex partial differential
equation, k-Wave suffers a lot from computation time. To accelerate
photoacoustic simulation, in this paper, we propose a straightforward
simulation approach based on superposed Wave (s-Wave). Specifically, we treat
the initial pressure distribution as a set of single pixels. Then by
pre-obtaining a standard sensor data from single pixel, we can easily use loop
and multiplication operators to change phase and amplitude of sensor data for
given pixels. We use three different 2D samples and two 3D samples to test the
time cost. The result of our proposed s-Wave method shows much less time
consumption compared with k-wave. Especially in a sparse configuration in 3D,
s-Wave is more than 2000 times faster than k-Wave, whiling getting nearly same
sensor data.
