非對稱雙波束主動掃瞄式洩漏波天線在衛星通訊上之應用

Abstract

非對稱雙波束主動掃瞄式洩漏波天線在衛星通訊上之應用 學生: 許祐豪 指導教授: 周復芳博士 國立交通大學電信工程研究所 摘要 無線通訊在最近的幾年可以說是蓬勃發展。由於洩漏波天線的波束位置與激發的訊號頻率相對應，故在本論文我們針對洩漏波天線提出了一些研究成果。 首先我們提出非對稱雙波束主動掃瞄式洩漏波天線，在此應用中分別使用了兩種不同型式的昇頻器，一種為單端電阻性昇頻器，另一種為主動性昇頻器。 在非對稱雙波束主動掃瞄式洩漏波天線中，我們使用雙端饋入洩漏波天線，一個X-Band的訊號經由一功率分配器分成兩路輸入這個雙端天線的饋入端，並在其中的一個饋入端點前加上一昇頻器，故有加昇頻器的這端便形成了一可掃瞄式的波束，而無昇頻器的這端形成一定位式的波束。在使用電阻式昇頻器的非對稱雙波束天線中，我們得到了約20度的單波束掃瞄角度，而在使用主動式昇頻器的非對稱雙波束天線中，我們得到了約22度的單波束掃瞄角度。 最後針對之前所提出的發射器，我們由孔隙饋入式洩漏波天線，發展出一可以兼具發射和接收的天線。觀察其發射與接收的幅射場型，可得知掃描角度分別為22度和16到18度。此種多波束孔隙耦合式洩漏波天線在收發模組(如智慧型天線系統)中擁有很大的發展潛力，因為收發模組只需使用單一支天線。

The X-Band Active Asymmetrically Scanning Dual-Beam Leaky-wave Antenna for Satellite Communication Student: Yu-Hau Sheu Advisor: Dr. Christina F. Jou Institute of Communication National Chiao Tung University Abstract In this report, an active asymmetrically dual-beam scanning leaky-wave antenna integrating with an upconverter to control the scanning beam is presented. Two kinds of upconverters are studied, which are a resistive HEMT upconverter and an active HEMT upconverter. The resistive HEMT upconverter has conversion loss. The active HEMT upconverter has conversion gain. The resistive asymmetrically dual-beam scanning leaky-wave antenna can provide a fixed beam and a scanning beam. The measured scanning beam provides a 20°scanning angle in H-plane from 10.2GHz to 11GHz and its measured maximum EIRP is 17dBm. The fixed beam EIRP (Effective Isotropically Radiated Power) is 21dBm. The active asymmetrically dual-beam scanning leaky-wave antenna also has a fixed beam and a scanning beam. The measured scanning beam provides a 22°scanning angle in H-plane from 10.2GHz to 11.5GHz and its maximum EIRP is 21dBm. The measured fixed beam EIRP is 20dBm. Theses antenna are suitable for microwave transceiver system. At last, we developed a transceiver / receiver antenna. It utilized the aperture-fed leaky-wave antenna to develop a multi-beam antenna. The transmitting signal fed into center aperture, and the feeding signal coupled to the leaky-wave antenna, and scanning dual-beam pattern was obtained. The receiving signal obtained from the end-side of the aperture-coupled antenna. Its transmitting and receiving radiation patterns are observed, their scanning angles as 22°and 16°~18°, respectively. This antenna has the potential to be used in the transmit/receive modules such as smart antenna systems because both modules can use only one antenna.