本論文將以2.92mm同軸連接器作為研究對象，其探討特性阻抗、介電係數、結構設計…等，進行2.92mm同軸連接器產品結構設計及電氣特性的優化；研究方式包含電氣特性模擬，以及成品實際測量，並且比較兩者的結果。
5G世代有三大主要特性:「高速度」、「低延遲」、「多連結」，而對於無線電傳輸的特性而言，頻段愈寬、頻率愈高，通訊速度就愈快，而讓同軸連接器在頻段內可以讓訊號的傳遞速度越快，進而符合5G特性高速度的需求，本研究希望以2.92mm同軸連接器為例，在40GHz的頻率範圍內，進行優化同軸連接器進而符合5G高速度的電氣特性要求，並且發展同軸連接器運用電磁模擬分析以及實際測量的技術方法，以作為同軸連接器設計之依據。
理論分析部分主要是運用CST STUDIO SUITE進行電氣特性模擬分析，說明如何建模、設定以及運用各種電氣參數進行產品設計及調整，進而產出電壓駐波比(VSWR)、特性阻抗、插入損耗的各式電氣特性結果，實際量測的部分是優化後結果進行生產組裝，進行實際的電氣測試，測試產品的電壓駐波比(VSWR)、特性阻抗、插入損耗，產出產品的電氣分析，使用的量測儀器主要為網路分析儀(VNA)。
本研究分別從模擬各項電氣特性參數以及實際量測產品電氣特性，發現具有相當程度的吻合，但還是會經由生產及組裝中所產生的公差，得出模擬與實際生產的結果還是有些許誤差，若將改善前與改善後的2.92mm同軸連接器進行實測比對，則在電氣特性各方面都有明顯的優化及將原本不良的地方給改善，因此本文可以應用於同軸連接器模擬設計及優化，提供給設計者及應用本研究做為參考數據。

This paper studied the 2.92mm coaxial connector and discussed its characteristic impedance, dielectric coefficient, structural design, etc., to optimize the structural design for better electrical properties. The research methods involved simulation of electrical characteristics and measurement of the finished product, from which the results of the two would be compared and analyzed.
The 5G technology has three main characteristics: "high speed", "low delay", and "simultaneous connections". In terms of radio transmission, the wider the range of bandwidth, the higher the frequency is and the faster the communication speed will be. The coaxial connector allows faster signal transmission speed within the specified frequency bandwidth, which satisfies the requirement of 5G high-speed transmission. This research would take the 2.92mm coaxial connector as an example and optimize its characteristic design to meet the electrical requirement of 5G high-speed transmission in the range of 40Ghz. Such development of the coaxial connector would be simulated for electromagnetic analysis and measured, in which the data would serve as the basis for coaxial connector’s design.
The theoretical analysis primarily relied on CST STUDIO SUITE software for simulation, by building the model, setting and applying various electrical parameters to better design and adjust various electrical characteristics of the product, such as voltage standing wave ratio (VSWR), characteristic impedance and insertion loss. The actual measurement involved conducting electrical testing of the assembled and optimized connector, which again included voltage standing wave ratio (VSWR), characteristic impedance and insertion loss, to produce an electrical analysis report of the test product. The main measurement instrument used was a vector network analyzer (VNA).
In this study, the electrical characteristics of the coaxial connector were simulated and measured, which were found to have considerable degree of match, even though there was variation tolerance between the simulation and the actual measurement as a result of production and assembly. When comparing the 2.92mm coaxial connector before and after the optimization, it showed significant improvement in all aspects of electrical characteristics, as the original defects were corrected. Therefore, this paper could be provided to designers as a reference of application for simulation design and optimization of coaxial connector.

摘要 i
ABSTRACT iii
誌謝 v
目錄 vi
表目錄 ix
圖目錄 x
第1章 緒論 1
1-1 前言 1
1-2 文獻回顧 2
1-2-1 國際標準規範 2
1-2-2 模擬分析 4
1-2-3 結構設計 9
1-2-4 介電係數 10
1-3 研究動機 12
第2章 基礎理論 13
2-1 傳輸線基礎特性理論 13
2-2 特性阻抗 14
2-2-1 阻抗匹配與阻抗不匹配[20][22] 14
2-2-2 衰減 15
2-3 電氣分析基本理論 15
2-3-1 訊號傳輸方式[19~20] 15
2-3-2 差動傳輸線的特性阻抗 15
2-3-3 眼圖 16
2-3-4 史密斯圖[5][19] 17
2-3-5 S參數[5][19] 18
第3章 實驗內容 20
3-1 本研究所使用軟硬體介紹 20
3-1-1 CST高頻分析軟體 30
3-1-2 CST數值計算[24] 31
3-1-3 網路分析儀(VNA) 35
3-2 計畫流程圖 20
3-3 實驗步驟 21
3-3-1 原始設計建模 21
3-3-2 TDR交叉探測 (Cross Probing) 25
3-3-3 外部導體模擬 26
3-3-4 絕緣體模擬 26
3-3-5 中心針模擬 28
3-3-6 模擬最佳化 29
3-3-7 網路分析儀實測 29
第4章 結果與討論 36
4-1 改善前模擬結果與實測 36
4-2 外部導體材質變更 39
4-2-1 金屬材料 39
4-2-2 非金屬材料 40
4-3 絕緣體改善 41
4-3-1 改變介電係數 41
4-3-2 結構變更 42
4-3-3 絕緣體外徑對於截止頻率之影響 44
4-3-4 絕緣體改善前與改善後之比對 45
4-4 中心針改善 50
4-5 最佳化模擬 53
4-6 模擬結果 61
4-7 網路分析儀實測 64
4-8 模擬與實測之結果比較 66
4-9 討論 69
第5章 結論 70
參考文獻 72

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