Hierarchical cascading in 2D FEM simulation of finite SAW devices with periodic block structure

Application of finite element methods (FEM) to the simulation of SAW devices has been constrained by the large number of degrees-of-freedom required, resulting in large memory usage and long computation times. Here, we propose a hierarchical cascading approach which takes advantage of the periodic structure typical of SAW devices. In this approach, each unique electrode period is modeled and simulated only once. Smaller blocks are cascaded to describe larger blocks until the whole device is modeled. This is equivalent to full simulation of the device with FEM, however — for structures with high degree of periodicity — with drastically reduced memory consumption and simulation time.