Chen Zhenglin, Zhang Qiaozhen, Fu Sulei, Wang Xiaoyu, Qiu Xiaojun, Wu Haodong
School of Electronic Science and Engineering, Nanjing University, Nanjing 210093, China.
Mechanical and Electrical Engineering, College of Information, Shanghai Normal University, Shanghai 200234, China.
Micromachines (Basel). 2020 Dec 22;12(1):5. doi: 10.3390/mi12010005.
In this paper, a hybrid full-wave analysis of surface acoustic wave (SAW) devices is proposed to achieve accurate and fast simulation. The partial differential equation (PDE) models of the physical system in question and graphics processing unit (GPU)-assisted hierarchical cascading technology (HCT) are used to calculate acoustic-electric characteristics of a SAW filter. The practical solid model of the radio frequency (RF) filter package is constructed in High Frequency Structure Simulator (HFSS) software and the parasitic electromagnetics of the entire package is considered in the design process. The PDE-based models of the two-dimensional finite element method (2D-FEM) are derived in detail and solved by the PDE module embedded in COMSOL Multiphysics. Due to the advantages of PDE-based 2D-FEM, it is universal, efficient and not restricted to handling arbitrary materials and crystal cuts, electrode shapes, and multi-layered substrate. Combining COMSOL Multiphysics with a user-friendly interface, a flexible way of modeling and mesh generation, it can greatly reduce the complicated process of modeling and physical properties definition. Based on a hybrid full-wave analysis, we present an example application of this approach on a TC-SAW ladder filter with 5° YX-cut LiNbO substrate. Numerical results and measurements were calculated for comparison, and the accuracy and efficiency of the proposed method were verified.
本文提出了一种用于表面声波（SAW）器件的混合全波分析方法，以实现精确且快速的仿真。利用所研究物理系统的偏微分方程（PDE）模型和图形处理单元（GPU）辅助的分层级联技术（HCT）来计算SAW滤波器的声电特性。在高频结构模拟器（HFSS）软件中构建射频（RF）滤波器封装的实际实体模型，并在设计过程中考虑整个封装的寄生电磁特性。详细推导了基于PDE的二维有限元方法（2D-FEM）模型，并通过COMSOL Multiphysics中嵌入的PDE模块进行求解。由于基于PDE的2D-FEM具有通用性、高效性且不受处理任意材料和晶体切割、电极形状以及多层基板的限制等优点。结合具有用户友好界面、灵活的建模和网格生成方式的COMSOL Multiphysics，它可以大大减少建模和物理特性定义的复杂过程。基于混合全波分析，我们给出了该方法在具有5° YX切割LiNbO基板的TC-SAW梯形滤波器上的示例应用。计算了数值结果并与测量值进行比较，验证了所提方法的准确性和效率。
