Fast FEM/BEM simulation of SAW devices via asymptotic waveform evaluation

Abstract

The finite element method/boundary element method (FEM/BEM) computation model applied to surface acoustic wave devices requires the solution of a large linear system for each frequency point. An asymptotic waveform evaluation technique is used to obtain an approximate solution of the linear system that is valid over a large frequency bandwidth. The approximate solution was shown to be very accurate and vastly reduces the computation time.

A Fast Optimization Algorithm of FEM/BEM Simulation for Periodic Surface Acoustic Wave Structures

“…Information 2019, 10, x FOR PEER REVIEW 2 of 11 [21,23,24]. Peach approximated Green's function by exponential terms to reduce the time cost in BEM [19].…”

“…To accelerate the accurate SAW device simulation, some optimization algorithms for the FEM and BEM calculation have been reported. Laude et al introduced asymptotic waveform evaluation (AWE) to reduce the FEM computation for periodic SAW structures [21]. Ke et al approximated the equations' coefficients by poles to simplify the solution of the equations [22].…”

“…Ventura et al reduced the dimension of algebraic equations by using the Chebyshev polynomial to approximate Green's function [20]. Wang, Luo, and Ke et al did more optimization in BEM based on Ventura's research [21,23,24]. Peach approximated Green's function by exponential terms to reduce the time cost in BEM [19].…”

Surface Acoustic WaveAmmonia Sensors Based on ST-cut Quartz under Periodic Al Structure

“…The FEM/BEM computation model can solve a large linear system for each frequency point. Laude et al [ 10 ] proposed an asymptotic waveform evaluation technique to obtain an approximate solution of the linear system that is valid over a large frequency bandwidth and vastly reduces the computation time. Gamble et al [ 11 ] take into account the effect of finite electrode resistance, which they used FEM to model the electrodes, BEM to the substrate, and pulse functions to approximate surface charge density, surface free charge, and surface potential.…”

A Two-dimensional Theory for Surface Acoustic Wave Propagation in Finite Piezoelectric Solids

“…Unlike bulk acoustic waves (BAW) in solids, which can be effectively analyzed with plate theories such as Mindlin plate theory, for example, demands for accurate analytical solutions in SAW device applications, which require wave propagation analysis in finite, plate-like, and anisotropic piezoelectric solids, have to be answered with finite element method and boundary element method for complete and practical analyses. Currently, as practical computational solutions are considered widely available for many engineering problems, for SAW applications, usually only the solutions from one representative period in a large periodical structure can be obtained in reality, due to the higher than usual vibration frequency in electrical circuit applications and the costly rigid threedimensional finite element implementation of piezoelectricity (Yong, 2001;Hofer et al, 2002;Yoon et al, 2003;Zhang et al, 2003;Laude et al, 2004). This, of course, places restrictions on applications of both analytical and numerical methods in the design and modeling of electrical devices utilizing SAW propagation in piezoelectric solids for sensing and actuating functions, and there have not been significant developments in meeting engineering needs.…”