應用基因演算法最佳化波導管功率分配器與號角天線設計

Optimization of Waveguide Power Dividers and Horn Antennas by Genetic Algorithm

陳劭宜(Shao-Yi Chen)

指導教授 ： 周錫增

元智大學/電機通訊學院/通訊工程學系/碩士(2007年)

摘要

本篇論文利用基因演算法發展出一套自動化的最佳化程式，能分別整合商用電磁模擬軟體CST以設計波導管功率分配器，以及整合商用電磁模擬軟體HFSS應用於設計線性極化號角天線。於波導管功率分配器設計中，我們利用基因演算法來執行幾何架構的最佳化運算，以獲得低反射功率、低傳輸功率損耗、指定輸出功率分配比例之模擬結果，並經由等效電路分析方法來驗證之；或者利用前人提出之架構，我們將可於簡短的時間內，設計調整出效能更優化之波導管功率分配器。在號角天線的設計中，為了因應現今衛星通訊之需求，我們選擇以瓦楞狀號角天線為基本架構，進一步探討發展出其他架構之可行性，並且藉由自動化之最佳化程式，將可減少設計調整繁複架構的尺寸變數時所耗費的時間，並達到天線場形高度對稱性、低反射訊號、與指定波束寬之圓極化天線效能。

關鍵字

基因演算法 ； 最佳化 ； 波導管功率分配器 ； 號角天線

並列摘要

This thesis develops a genetic algorithm (GA) based optimization procedure which can be integrated with CST, HFSS, the commercial EM software, to design the waveguide power dividers and linearly polarized horn antennas. In order to achieve the low reflected low power, transmission loss and desired result of power division, GA is utilized to adjust the component structure which the commercial codes are used to perform the analysis. Also the method of equivalent circuit is used to initiate the design. From the proposed models, we can design a waveguide power divider with better performances in a short time. About the design of horn antenna, we select the corrugated horn antenna as a model for the applications of modern satellite communication. This code allows one to optimize the structures models which have symmetrical patterns, low reflected signals, and desired beamwidth of circularly polarized antenna. Numerical examples demonstrate the efficiency of the design procedure!

並列關鍵字

genetic algorithm ； optimization ； waveguide power divider ； corrugated horn

參考文獻

[1] S. Christopher, et al., “Design Aspects of Compact High Power Multiport Unequal Power Dividers,” Phased Array Systems and Technology, 1996., IEEE International Symposium, October 1996, pp. 63-67 .

[2] S. L. Chen, H. R. Chuang, “Comparison of the Design of A Contoured-Beam and An Elliptical-Beam Satellite Offset Reflector Antennas to Cover the Taiwan Island Region for Satellite Communications,” IEEE Transactions on Broadcasting, Vol.43, No. 2, June 1997, pp. 117-126.

[4] R. S. Yahya, M. Eric, Electromagnetic Optimization By Genetic Algorithms, John Wiley & Sons, New York, 1999.

[8] T. Takahashi, S. Sakanaka, M. Izawa, “Development of An Asymmetric Power Divider for A High-Power RF Distribution System,” Nuclear Science, IEEE Transactions on Nuclear Science, Vol. 48, Issue 4, Part 3, August 2001, pp. 1592-1597.

[10] J. H. Holland, Adaptation in Natural and Artificial System, Ann Arbor: The University of Michigan Press, 1975.