本論文提出了一個具備寬頻雷達反射截面積抑制頻帶的雷達罩設計，該雷達罩係以不同共振頻率之帶拒單元所形成的多層頻率選擇表面來實現。有別於傳統頻率選擇表面所形成的雷達罩大多以帶通單元構成，本論文所提出的設計則是透過調整多層板的間距製造期望的帶通頻帶。多層板結構的電磁響應通常難以評估，原因是多層板間的多次反射與透射。本研究為了解決這個問題，因此開發了對應的高頻數值方法，即可有效率地進行評估與分析。此方法是先透過全波模擬獲得單層板的穿透與反射頻率響應，建立完整的資料庫，再利用射線追蹤技術，將單層板響應合成出多層板的反射與透射頻譜。在此方法的輔助下，不僅能快速地進行優化設計，也能透過參數分析得知如何調整多層板結構的散射特性。本論文進行了數個不同多層板配置的反射率與透射率量測，其量測結果也與高頻數值方法之合成結果趨勢一致，因此驗證本論文所提出的高頻數值方法可應用於具共振週期性結構的雷達罩設計。

In this thesis, multi-layer FSS designs comprising band stop type elements of different frequencies are developed to serve as a radome to provide an extended RCS suppression band. Unlike conventional FSS-based radomes that are made of bandpass elements, the proposed design yields transmission bands by adjusting the spacing between cross layers. Note, the spectral response of this multi-layer structure is difficult to assess due to interlaced FSS elements and multiple bounces between layers. A high frequency method is therefore developed to provide time-effective estimations. This technique is based on modeling intrinsic properties of a single-layer homogeneous FSS design as spectral functions using the full wavelength method. Reflection and transmission spectra of stacked structures are synthesized using single-layer responses via the ray tracing technique. The method not only delivers an effective design optimization mean, but also provides physical insight about how the favorable scattering features are achieved. Comparisons of high frequency estimations and prototype measurement results exhibit satisfactory agreement. Design optimization can be facilitated to achieve different performance objectives with the proposed design method.

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[32] 陳昱夆, 具互補式反射與透射特性之可重置頻率選擇表面設計, 國立臺灣科技大學, 碩士論文, 民國110年