本論文第一部分提出一款電控式波束可重置的雙頻槽孔天線陣列，可應用於LTE無線通訊的小細胞基地台。所提出之天線整體大小為350 (L) × 265 (W) × 40 (H) mm3，可達到LTE 1710~1880 MHz及2500~2690 MHz頻段之涵蓋。利用電控式相位延遲電路，使天線陣列提供三種主波束偏轉角度，搭配演算法能根據使用情境調整波束偏轉角度，提升網路涵蓋效能。經實作實測，驗證所提出之天線具高指向性及波束偏轉效能。
第二部分提出一種可在遠場無反射實驗室內進行的單站雷達反射截面積量測方法，配合向量網路分析儀及相應的訊號處理方式，可計算出目標物之RCS值，經與模擬結果比較驗證了該量測方法的準確性。並應用此方法量測了一款RCS抑制結構及一款商用小型無人機，並探討其RCS特性。
第三部分提出一種在毫米波頻段增強RCS的結構設計方法，並根據此方法設計星狀、環形、網狀等三款寬角度RCS增強結構，並以統計分析評估各結構之RCS增強表現，結果顯示網狀結構具有最穩定之RCS增強效果。吾人實作一組五環形面的RCS增強結構，其近場量測結果與遠場模擬結果有相同的RCS增強趨勢，顯示此結構於實際應用上可提供寬角度RCS增強效果。

In the first part of this thesis, a beam reconfigurable array antenna is proposed for LTE base station. The physical size of the proposed array is 350 (L) × 265 (W) × 40 (H) mm3. It provides a coverage on 1710 to 1880 MHz and 2500 to 2690 MHz for LTE band 3 and 7 . The proposed array provides three different main beam tilting angles. It allows the base station to switch the tilting angle based on the application scenario in order to maximize the network coverage. Measurement results show that the proposed antenna has a high directivity and the beam switching feature.
The second part proposes a radar cross section measurement method which is implemented in a far-field anechoic chamber. A network analyzer is used to measure the frequency spectrum of the target. The RCS of the target is estimated and compared with simulated results. An RCS reduction structure and a commercially available UAV were measured. There RCS characteristics are analyzed.
The third part of this thesis proposes a millimeter wave RCS enhancement method. Based on this method, three broad-angle RCS enhancement structures including star, ring, and mesh shaped structures were proposed. Statistics of these structures were examined and the results show that the mesh structure can provide the most stable performance over a broad angular region. A 5 ring structure was fabricated and measured in a near-field range. Measurement results, which are similar to far-field simulated ones, indicate that the structure can provide a broad-angle RCS enhancement performance.

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