本研究針對毫米波封裝天線（Antenna-in-Package, AiP）輻射場型測試中常見的治具干擾問題，提出並驗證了一套低干擾、高準確度的量測治具設計方案。首先，基於5G 毫米波（24–40 GHz）與未來6G頻段需求，說明了AiP技術的重要性與天線輻射場型量測的挑戰，包括高頻下波長短、路徑損耗大，以及測試空間受限等問題；並介紹了MW5與MW5x量測系統架構及CATR技術，以作為設計依據及實驗平台。
在Broadside 天線量測治具設計部分，本研究以MW5系統為基礎，通過模擬分析不同材質（如FR4、Roger5880、Rohacell-HF）、尺寸（直徑12、15、18 cm）、厚度（取整數倍λg/2）與挖孔結構對天線S參數、增益、輻射效率及場型的影響；結果顯示：選用低介電常數且低損耗材料可減少近場吸收與反射、維持共振頻率與匹配；治具尺寸過大或厚度過厚易導致近場耦合、吸收效應與聚焦現象，進而降低遠場增益且扭曲場型；適度挖孔則可降低等效εr與tanδ，改善匹配並提升效率。基於模擬結果，實際製作直徑約12 cm、厚度約1 cm之Rohacell-HF圓形治具，並在中央挖錐形孔洞，於MW5系統中進行下針與OTA量測。
在Endfire 天線量測治具設計部分，基於MW5x系統可實現探針台暗室內掃描四分之三圓之優勢，針對印刷偶極Endfire天線（32 GHz）設計了低Dk&Df圓形治具，模擬不同直徑（20、30、40 mm）、厚度及邊緣切割對S參數、增益、效率與HPBW的影響；結果指出：治具尺寸與厚度的選擇需平衡相位補償效應與吸收損耗；適度切割並將天線置於邊緣可減少近場多餘介質影響，使量測結果更貼近自由空間模擬。實際量測驗證了模擬預測，並證實所選Rohacell-HF材質與幾何參數設計能提升Endfire 測試準確度。
綜合Broadside 與Endfire 實驗結果，本研究證明在量測階段需完整納入材料頻率相依特性、尺寸與結構設計，並於實測中先取得自由空間基準，再逐步引入治具變化以量化其效應；此外，結合SOL/TRL校正，可進一步消除測試系統帶來的相位延遲與反射影響，確保量測結果真實反映天線本體性能。未來研究可深入探討更複雜形狀或多材料複合結構治具的設計方法，以及自動化校正演算法在量測中的應用，以進一步提升AiP天線量測的效率與可靠性。

This study investigates design strategies for measurement fixtures in millimeter-wave Antenna-in-Package (AiP) radiation pattern testing to minimize interference and enhance measurement accuracy. Full-wave simulations assessed the influence of material properties (favoring low permittivity and low loss tangent) and geometric features (such as overall size relative to guided wavelength, perforations, and edge modifications) on antenna performance metrics including impedance matching, radiation efficiency, gain, and pattern fidelity.
Results show that selecting low-dielectric, low-loss materials reduces near-field absorption and reflections, preserving resonance and matching, while excessive material volume or continuous structures can induce coupling and dielectric focusing that degrade far-field characteristics. Introducing openings or trimmed edges effectively lowers the effective permittivity and loss tangent, improving matching and efficiency. Prototype fixtures based on these insights were fabricated and evaluated using advanced measurement systems with near-to-far-field transformations, comprehensive calibration (e.g., SOL/TRL), and de-embedding procedures to isolate intrinsic antenna behavior.
Experimental findings aligned with simulation predictions, demonstrating that optimized fixture design yields measured radiation patterns closely matching free-space conditions. This methodology offers practical guidelines for AiP fixture design. Future research may extend to more complex shapes, multi-material composites, and automated or machine-learning-based optimization and calibration workflows to further improve measurement reliability and efficiency.

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