本論文首先提出利用可變電容來調整螺旋天線的SWR值，如此可以節省許多在室外調整螺旋天線的時間。其次，本論文提出了能夠操作在7.8125 MHz頻段之頻率調變連續波雷達系統架構，並且利用實驗進行驗證，以確保與台灣海洋研究中心之高頻測流雷達系統都有著相同的功能。
實驗部分首先組建雷達系統之接收端，利用實驗及儀器來逐步確認雷達架構的各端點之參數是否與台灣海洋科技研究中心之高頻測流雷達系統之接收端相同。確認相同後便利用AD9854晶片作為IQ之發射端，以實現整個雷達系統架構，最後則是使用兩個方法來量測本論文提出的頻率調變連續波雷達系統。第一個方法為調整發射源之發射參數，利用頻寬80MHz和掃頻速度0.00005s的發射訊號並加上延遲22 ns的延遲線，以量測拍頻頻率是否有符合預期。第二個方法為利用RC delay的方法來作為該雷達架構的時間延遲，使用發射源發射參數為，中心頻率7.8125MHz、頻寬50KHz和掃頻速度0.455s，並確認該頻率調變連續波雷達系統所得到的拍頻頻率符合預期。此外，本論文也利用RC delay的方法驗證了台灣海洋科技研究中心之雷達系統。

This paper first came up with a method to adjust the SWR value of helical antennas using variable capacitors. This greatly reduced the time spent on manually adjusting outdoor helical antennas. Furthermore, this work presents a Frequency Modulated Continuous Waveform (FMCW) radar system framework that operates at the 7.8125MHz frequency range. Through experiments, we verified that our framework possesses the same functionality as the HF Radar Current Measurement System at Taiwan Ocean Research Institute. For the experiments, we first set up a receiver for the FMCW, where instrument readings are used to ensure that the parameters match with those on the HF Radar Current Measurement System at Taiwan Ocean Research Institute. AD9854 chips are used as the IQ transmitter to finalize the FMCW radar framework. We presented two methods to verify the functionality of the FMCW system: The first method adjusts the transmitter parameters. Using signals with a bandwidth of 80MHz and sweep rate of 0.00005s, we apply a 22ns delay line and measure the beat-frequency. The second method utilizes RC delays. The transmitters are set to emit a signal with center frequency of 7.8125MHz, bandwidth of 50KHz and sweep rate of 0.455s. The beat-frequency measured from both experiments confirms that FMCW’s functionality indeed matches that of the HF Radar Current Measurement System at Taiwan Ocean Research Institute.

目錄
論文審定書 i
誌謝 ii
摘要 iii
Abstract iv
目錄 v
圖次 vii
表次 xi
第一章 序論 1
1.1研究背景與動機 1
1.2頻率調變連續波雷達系統簡介 2
1.3海洋測流雷達系統介紹 4
1.4章節規劃 9
第二章 螺旋天線駐波比之簡易調整方法 10
2.1螺旋天線原理 10
2.2實驗儀器介紹 13
2.3簡易調整螺旋天線之設計 14
2.4簡易調整螺旋天線實驗過程模擬及驗證 16
2.4.1 實驗室內-27MHz螺旋天線螺距大小及FR4不同管長實驗 16
2.4.2實驗室內-27MHz螺旋天線增加可變電容實驗 24
2.4.3室外-27MHz、7.8125MHz螺旋天線螺距大小及增加可變電容實驗 28
2.4.4 2.4GHz螺旋天線場型實驗 33
第三章 連續調變連續波雷達子系統設計及驗證 36
3.1子系統元件介紹 37
3.2測量儀器介紹 39
3.3子系統實驗與驗證 41
第四章 連續調變連續波雷達系統設計及驗證 45
4.1頻率調變連續波雷達公式推導 45
4.2元件及儀器介紹 47
4.3完整系統架構設計 48
4.3頻率連續波雷達系統實驗與驗證 49
第五章 結論與未來展望 59
參考文獻 60

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