運用基因演算法於微帶線演進最佳化搜尋以完成微波被動電路與主動電路設計

Abstract

在這篇論文研究中，以基因演算法微帶線演進最佳化搜尋方式設計微波電路。電路元件排列型式及微帶線結構尺寸等…皆表示成為一序列的參數型態。接著再以基因演算法針對這一序列的參數作最佳化搜尋、演進，使其滿足我們預先制定的電路特性及功能。透過S參數的轉換顯現並證實電路的頻域響應特性。文章內容包含了兩個部分的應用。第一個主題是：以基因演算法於微波被動電路的設計，包括了雙頻帶通濾波器(Dual-Band Band-Pass Filter)以及極寬頻帶通濾波器(Ultra Wide -Band Band-Pass Filter)的設計及實作量測。第二個主題是：運用基因演算法於微波主動電路設計，我們以低雜訊放大器(LNA)作為設計範例，將設計結果以微波模擬軟體作驗證。經由詳細的基因演算法實行準則及概念分析，再以實際的設計實作範例，得到符合目標的結果，並且有效地引導、介紹這種設計方式。電路形式上的限制及多目標搜尋結果都會在最佳化搜尋的過程中詳盡討論之。這些範例結果證實了本篇文章所提出之方法能夠廣泛地運用在微波電路型式及結構最佳化設計。

Evolutionary optimization of microstrip-line element in microwave circuit design is presented in this paper. Topology and dimensions of microstrip elements are expressed by sets of parameters. The sets of parameters are then optimized by genetic algorithms (GA) to satisfy our circuit performance or specifications. The S-parameters are synthesized to obtain and verify the response of the circuit. The applications discussed include two topics. In the first part, we investigate the microwave passive circuit design using GA: dual-band band-pass filter and ultra wideband band-pass filter synthesis and implement. In the second part, we utilize genetic algorithms in microwave active circuit design: low noise amplifier (LNA) design and simulation. Step-by-step implementation aspects of the GA are detailed, through an example with the object of providing useful guidelines for the synthesis method. Circuit pattern constraints and multi-objective design goals are also implemented and discussed in the optimization process. These results have validated our proposing procedure.