最近幾年由於無線通訊市場的蓬勃發展即自動化應用的廣泛推廣，對於小型發射器、主動天線、空間功率結合器及雷達感測器的需求越來越大。洩漏波天線是最近研究的領域，因為它具有頻率掃瞄的特性，所以可以被用在掃瞄天線上，用來取代需要繁複驅動電路的相位掃瞄式天線。
在此，我們使用非對稱饋入洩漏波天線完成了兩種應用，第一種是回饋式主動洩漏波天線，另一種是可控式雙波束天線。前者完成了工作在8.23GHz的主動天線，成功的壓低了反射波束，使其與主波束差距達到15dBm，而最大有效輻射功率有19.5dBm，後者則使用單刀雙擲開關當作控制電路，使得天線的輻射場型可以在雙波束和單波束中切換，並且可將接收和發射天線結合在同一支天線上，此外，藉由頻率的調整，在雙波束模式時，波束可以從36度掃到64度，而單波束模式，則可掃動40度（一邊各掃20度）。

In recent years, due to the increasing of wireless communication markets and automatic applications, the needs of compact transmitters, active arrays, spatial power combiners and radar sensors will increase steadily. The leaky-wave antenna is an area of recent research. Because of its frequency scanning ability, it could be used to provide antenna beam steering instead of conventional phase scanning techniques, which require complex associated drivers.
In this report, we used the asymmetric leaky-wave antennas to produce two kinds of applications. The first one is Active Integrated Feedback-Amplifier Leaky-wave Antenna Design with Suppressed Back Lobe, and the other is Dual-Beam Leaky-wave Antenna with Control circuit. The first one successfully suppressed the back lobe to be lower than main beam about 15dB at 8.23GHz with EIRP 19.5 dBm and the leaky-wave antenna length is only 9cm. The second one using SPDT as control circuit can change the radiation pattern as one or dual beam receiving or transmitting antenna. Besides, by changing the frequency, dual beam mode can scan from 36°to 64°as the operating frequency from 10.6 GHz to 9.2 GHz ( total scanning angle about 64°) and one beam mode can scan about 40°as the operating frequency from 9.3GHz to 10.4GHz ( each left and right main beam covers 20°).

CHAPTER 1 INTRODUCTION
1.1 Motivation……………………………………………………………………1
1.2 Review………………………………………………………………………..2
1.3 Over view…………………………………………………………………….3
1.4 Reference……………………………………………………………………..3
CHAPTER 2 THEORY of ASYMMETRIC FEEDING LEAKY-WAVE ANTENNA
2.1 Introduction………………………………………………………………….5
2.2 Theory of Leaky-wave Antenna…………………………………………….5
2.3 Asymmetric Feeding Leaky-wave Antenna………………………………...7
2.4 Reference…………………………………………………………….…….11
CHAPTER 3 AN ACTIVE INTEGRATED FEEDBACK-AMPLIFIER LEAKY-WAVE ANTENNA DESIGN WITH SUPPRESSED BACK LOBE
3.1 Introduction…………………………………………………………………12
3.2 Amplifier and Bandpass Filter Subcircuit…….…………………………….14
3.2.1 Amplifier Basic Theory………………………………………………...14
3.2.2 Microwave Amplifier Device…...……………………………………...15
3.2.3 Design and Simulation of Microwave Amplifier………………………16
3.2.4 Bandpass Filter…………………………………………………………17
3.2.5 Amplifier and Bandpass Filter Subsystem……………………………..19
3.3 Active Integrated Antenna Design and Measurement………………………20
3.4 Conclusion and Future Study…………………………………………….…21
3.5 Reference……………………………………………………………………28
CHAPTER4 ASYMMETRICALLY FEEDIGN DUAL-BEAM LEAKY-WAVE ANTENNA WITH CONTROL CIRCUIT
4.1 Introduction……………………………………………….………………...30
4.2 P-i-n Diodes ControlCircuit………………………………………………...31
4.2.1 Comparison Device for Control Circuit………………..………………31
4.2.2 p-i-n Diodes………………………………………………………….…32
4.2.3 p-i-n Diodes Switches………………………………………………….33
4.2.4 SPST Design and Measurement………………………………………..37
4.2.5 SPDT Design and Measurement……………………………………….44
4.3 Dual-Beam Leaky-wave Antenna with Control Circuit…………………….47
4.4 Conclusion and Future Study……………………………………………….53
4.5 Reference……………………………………………………………………55

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[2] W. Menzel, "A new traveling wave antenna," in Proc. 8th European Microwave Conf., 1978, pp302-306
[3] A. A. Oliner and K. S. Lee, "The nature of the leakage from higher modes on microstrip line," 1986 IEEE Intl. Microwave Symp. Digest, pp. 57-60, Baltimore, MD, June 1986.
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[5] G. J. Jou and C.-K. Tzuang, "Oscillator-type active-integrated antenna: The leaky-mode approach," IEEE Trans. Microwave Theory Tech., vol. MTT-44, pp. 2265-2272, Dec. 1996
[6] Cheng Chi HU, Jin Jei Wu, and Christina F. Jou, " An Asymmetric Feeding X-Band Active Frequency-scanning Leaky-wave Antenna," IEEE Trans. Microwave Theory Tech., vol. MTT-44, pp. 2265-2272, Dec. 1996