Differentiation operation in the wave equation for the pseudospectral method with a staggered mesh

In the present analysis we introduced a calculation strategy of the staggered grid differentiation by using the real value FFT and real inverted FFT for the pseudospectral method and applied the technique to seismic wave simulation. The calculation method introduced here is one third faster on average than the traditional differentiation method by using the complex FFT. The introduced differentiation strategy is very efficient in economy. For example we apply the staggered grid differentiation by real valued FFT to the simulation of seismic wave propagation in inhomogeneous medium. The results show the validity of the present method.