无线传感器网络微型节点设计的电磁建模方法

为解决微型无线传感器节点设计过程中无法分析射频微机电（RF MEMS）器件微小可动结构的电磁特性问题，提出一种电磁建模方法——变形时域交替方向隐式有限差分法。采用有限差分技术，引入时间变量实现一维垂直运动结构动态方程的时域离散；讨论了时域交替方向隐式有限差分法（ADI-FDTD）的三维数值色散关系；提出线性电（磁）介质参数插值的方法，解决了运动结构的机械时空步与电磁时空步的不一致问题，实现了复杂三维动态结构的时域描述。仿真实验验证了该方法可行有效。

Electromagnetic Modeling of Micro Sensor Node for Wireless Sensor Network

Modeling radio frequency micro-electro-mechanical system (RF MEMS) device for electromagnetic analysis is difficulty, especially with small feature size and movable structures. A new electromagnetic modeling method, deformed alternating-direction implicit method finite difference time domain (DADI-FDTD), is proposed. The dynamic equation of motion is dispersed in time domain using finite difference methods (FDM). Numerical dispersion is discussed in the three-dimensional ADI-FDTD method. A new algorithm, dielectric interpolations, is presented, it is capable of solving the conflict of the time and special steps between the mechanical portion and electromagnetic (EM) portion. And it’s able to implement the EM modeling in time domain of complex three-dimensional structures. Simulation results demonstrate the feasibility of the method.