Automatic Wavelet Localization and Adaptive Meshing of Physical Relevances in Device Simulation

In this paper we report how a wavelet-based adaptive method (WAM) able to automatically detect sensible regions is integrated within CAD softwares for device simulation. The wavelets localization property drives a procedure which constructs an anisotropic grid, whose density remarks the internal structure of physical relevances. The mesh generation is performed considering the necessity of a Delaunay triangulation which avoids the presence of obtuse angles: for this reason Steiner points are inserted. Ad hoc procedures render the adaptation gradual: there is no redistribution of grid points and yet the passage between refined and coarse regions is obtained with a smooth grading. Such a grid construction produces smooth characteristics, even for a fully dynamic adaptation in critical quasi-stationary simulations. 2D practical examples are discussed to validate the proposed approach