6D-5 A 2D P-Matrix Model for the Simulation of Waveguiding and Diffraction in SAW Components (Invited)

The 2D P-matrix model has proven to predict 2D propagation effects in a wide spectrum of SAW components for different applications reliably. With reasonable computational effort, a very accurate simulation of the electrical characteristics of SAW devices is achievable. After an overview of different possible approaches proposed in the literature for the inclusion of 2D effects into device simulation, the method implemented and used by Epcos is described in some detail. Comparison to other methods, especially the 2D COM model is made. The modeling of the coupling of forward and backward propagating modes in reflective gratings, which is crucial for obtaining high quality results, is highlighted. A wide variety of different application examples (inline filters using SPUDTs, resonators, filters with slanted finger transducers) will demonstrate that the 2D P-matrix model not only gives reliable predictions of electrical characteristics, but lends detailed insight into the physics of a device under consideration. Thus, it sets up a basis allowing systematic approaches for the suppression of transversal modes