- 學位論文
雙頻微帶天線的輻射場量測之探討
The Investigation of Radiation Measurement for Dual-Band Microstrip Antenna
摘要
對於一般通信天線的設計，首要目標為天線具單波束之輻射，而相關研究皆以此為目標。從結構的角度，對這些研究可區分為單層雙頻與雙層雙頻微帶天線，本文以實際量測的方法對此兩種不同結構所設計之天線輻射進行驗證與分析。 為驗證模擬與實際的共振頻率和輻射場型的一致性，本論文以實際測量的方式驗證雙頻微帶天線的輻射場與共振頻率數據。其中的作法是將兩種結構各式設計雙頻微帶天線實際製作出來，再利用天線量測系統進行量測。完成實際的輻射場量測後，再針對其實際數據與理論值或研究數據進行探討。 根據實際量測的結果，就單層結構的雙頻微帶天線的實際量測值而言，不論是共振頻率與輻射場的差異都非常小。相較之下，雙層結構的雙頻微帶天線的實際量測值差異性較大。其中之原因，可能是雙層雙頻微帶天線的製作困難度較高，而且這種人工所製作的結構在實驗過程中容易受到破壞。但就結果而言，實際量測所得到數據顯示，無論是單層或是雙層結構，本論文證實這些雙頻微帶天線皆具備單波束輻射場。 本論文實際量測之方式，適用於不同頻段與不同結構之天線，因而原有設計再多加一層驗證。除了原有的設計可更具有可靠度，微帶天線的實際輻射場與共振頻率的量測數據也可以在掌握中。這些數據可以提供原設計者修改或偵錯的基礎，因此本文驗證的結果具高度參考價值。
並列摘要
For the demands of antenna design in general communication systems, a major work is to make an antenna radiating with single-beam pattern, Recently, the goal to design dual-band microstrip antennas is achieved by several related researches, but the verification for radiation pattern is not finished. From the structure point of view, these antennas can be classified as antennas with single layer or double layer. This thesis uses practical technique of measurement to verify and investigate the radiation of these various antennas. In order to prove the consistency between simulation and experiment, this thesis uses measured data of resonant frequencies and radiation patterns. The procedure is to fabricate these two types of dual-band antennas, and use chamber equipment to measure. Later, the investigation on the measured and theoretical data is done after the radiation measurement. According to the measured results, the difference for resonant frequencies and patterns of the single-layer dual-band antenna are pretty little. In contrast, the difference is much larger for the double-layer ones. The reason could be due to the difficulty of fabrication for this type of antenna, or the man-made antenna samples are vulnerable during experiments. Fortunately, the measured results show that these dual-band microstrip antennas can radiate with single beam in an acceptable range, both for the single- and double- layer ones. The technique used for radiation measurement is practical, and the procedure is eligible for the microstrip antennas at various frequency bands or even for various structures of antenna. The work done in this thesis ensures alternative verification for these original antenna designs. In addition to the reliability of these designs, the data of resonant frequency and radiation of an antenna is also handled. The data also offers valuable information for the designer to finish a work if antenna modification or bug removal is required.