本論文主要基於頻率選擇表面(或稱週期性結構，或在光學中稱為光子晶體)設計取代傳統的Salisbury screen 所製作之電阻表面電路模擬雷達吸波結構，雖然在過去的文獻中已有所謂的最佳化設計，但其往往需要使用介電系數非常特殊的材料，使得其設計變得不太實際。基於規格要求，我們分析頻帶內適合使用的材料，先在負載端設計一頻率選擇面與材料虛部阻抗匹配，並參考文獻設計Jaumann多層介質結構的電磁波吸波器，利用四分之一波長阻抗轉換器原理，在選定的材料上設計阻抗轉換器，達成阻抗匹配且設計符合實際上可製作的吸波器，以活化並充分利用現有資源，論文中也以全波模擬軟體與實驗來驗證設計理論。本論文製作之寬頻吸波器量測結果與全波模擬有相同的趨勢且有良好的吻合度。本論文所設計完成的寬頻吸波器可應用於X頻段的衛星通訊系統。;In the thesis, based on the design of periodic structure (photonic bandgap, or frequency selective surface), a circuit analog radar absorbing structures (RAS) is fabricated by replacing the resistive sheet of a Salisbury screen by a frequency selective surface (FSS). In the literature, related research and design methods have been proposed. But the optimal designs have to use very specific dielectric coefficient of the material. So, the design is not so easy to achieve. Based on the specification of the absorber, we will analyze the frequency band of suitable material. First, we will design the frequency selective surface (FSS) to match the imaginary part of the impedance of the material. Then, to refer the literature of the Jaumann multi-layered structure, we design the impedance converter on the load by the principle of one-quarter wavelength impedance converter. It will be well-matching and realistic. The validity of the procedure is verified using full-wave EM simulations and experimental characterization of a fabricated prototype of the proposed thin loads for X-band planar absorbers. The proposed thin loads for X-band planar absorbers can be used in X-band satellite communications systems.
