Simultaneous Optimal Design of Multifunctional Acoustic Wave Device through Structural Analysis of Electrodes

声表面波(SAW)器件在手机等移动通信设备的射频电路中得到了广泛的应用。为了减少射频电路中使用的电子元器件的数量，本研究提出了一种多功能声表面波器件的优化设计技术。这项研究的结果可以概括为以下三点。1)将声表面波滤波器的结构设计归结为一个三目标优化问题。然后将一种基于最新进化算法的多目标进化算法(MOEA)，即差分进化算法(DE)应用于优化问题。为了分析电极结构与器件性能之间的关系，利用主成分分析对MOEA得到的一组解进行了统计评价。2)针对具有四个以上目标的多目标优化问题，提出了一种新的多目标优化算法。新的MOEA算法采用了一种快速逼近排他超体积的算法作为求解的标准。3)为了利用多核处理器进行多功能声表面波器件的设计，开发了并行DE程序。

Surface Acoustic Wave(SAW) devices have been used widely in Radio Frequency(RF) circuits of mobile communication equipments such as cellular phones. In this study, an optimal design technique of multifunctional SAW devices is developed for reducing the number of electronic parts used in RF circuits. The results of this study can be summarized by the following three points. 1) The structural design of a SAW filter is formulated as a three-objective optimization problem. Then a Multi-Objective Evolutionary Algorithm(MOEA) based on the latest EA, i. e., Differential Evolution(DE), is applied to the optimization problem. In order to analyze the relationship between the structure of electrodes and the device function, a set of solutions obtained by MOEA is evaluated statistically by using the principal component analysis. 2) A new MOEA is proposed for solving the multi-objective optimization problems which have more than four objectives. A fast approximation algorithm for the exclusive hypervolume is used by the new MOEA as the criterion of solutions. 3) In order to utilize multi-core CPUs for the design of multifunctional SAW devices, a concurrent program of DE is developed.