标题: | 新型被动与主动式整合型天线之设计与应用 Novel Passive and Active Integrated Antennas:Designs and Applications |
作者: | 周咏晃 Young-Huang Chou 钟世忠 Shyh-Jong Chung 电信工程研究所 |
关键字: | 主动整合天线;被动整合天线;三埠180度天线混合器;波束可切换式主动天线阵列;偶合震荡器;注入锁频;无相移器扫描式主动天线阵列;Active Integrated Antenna;Passive Integrated Antenna;Three-Port 180 degree Antenna Hybrid;Beam-Switching Active Antenna Array;Coupled Oscillator;Injection Locking;Phase Shifterless Beam Scanning Active Antenna Array |
公开日期: | 2000 |
摘要: | 本论文旨在研究与设计新型被动式与主动式整合型天线。首先将提出的是新设计的整合天线单元,称为180度天线混合器∶此架构是以平衡式功率分配器为基础,利用双埠孔隙偶合微带天线所具备之辐射电阻,来取代其中所需的平衡电阻。此电阻值可在不影响天线中心频率的情况下,适当调整天线本身以及耦合孔隙的大小而达成所需大小。然后利用此设计制作出的整合型天线单元,我们将提出其实际上的应用,包括单平衡式混频器、主动天线及双辐射模天线阵列将被提出并制作量测其特性。其中单平衡式混频器是利用混频二极体直接接于天线混合器之平衡埠,射频讯号由天线接收进来,而本地振荡讯号则从非平衡埠馈入。主动天线是运用回授的形式,回授路径由非平衡埠与平衡埠的其中之一所形成,锁频讯号则可由另一平衡埠馈入。双辐射模天线阵列是把180度混合器利用四分之三波长的传输线与另一孔隙偶合微带天线以形成两个单元的阵列,在如此架构下将分别于非平衡端的两个埠得到同相及反相的辐射场型。 接着在论文中将介绍振荡器同步原理及耦合振荡器的基本原理。在此原理下,对于单一振荡器注入锁频的原理及各个振荡器间之耦合量对讯号相位所造成的影响将有详细的描述与讨论。根据这项基础,我们将于论文中提出一个新的耦合振荡器理论,在此引进了另外不同机制的注入讯号,文中将探讨在这两个注入讯号同时影响下,偶合震荡器的特性及其对各单元间讯号相位的影响。 最后我们将提出回授式主动天线的设计与应用,这是利用双槽耦合微带天线之结构于回授振荡器设计时之回授路径上,并配合其中放大器及相位调整之传输线,就可满足振荡所需之增益及相位条件,以完成主动天线之设计。在本文中我们将使用两种不同的传输线,一是微带线,另一是共面波导,来完成设计,并将讨论其特性的差异及制作时所需的考量。在应用上,两组具有不同功能之主动天线阵列将于本论文中提出,一是切换式主动天线阵列,另一是两个单元无相移器扫描式主动天线阵列。根据上述所提出之新的耦合振荡器理论,我们在这两个应用的线路中,加入了内部耦合线路,此线路从第一个振荡器取出讯号经由放大器放大后再利用耦合器注入其他的振荡器中。经由切换放大器的状态,天线阵列在此两个不同注入讯号的影响下将分别产生同相的辐射场形及反相的辐射场形。此外,当方大器的偏压是由关闭逐渐调整至全开时,在两个单元的天线阵列中,其彼此间的馈入讯号相位将逐渐的由同相变成反相或逐渐由反相变成同相,而产生扫描的结果。 In this thesis, the new passive and active integrated antennas were proposed and implemented. First, a novel three-port passive antenna, named antenna hybrid, is designed and demonstrated. This structure is composed of a Wilkinson power divider with the isolation resistor replaced by an aperture-coupled patch antenna. The equivalent series impedance of the antenna can be adjusted to the required one by properly choosing the dimensions of the patch and the coupling aperture. The measurement results showed good agreement with the characteristics to be designed. Next, three applications for this integrated antenna have been proposed and demonstrated, that is, a balanced mixer, an active transmitting antenna, and a dual-radiation-mode antenna array. Secondly, several brand new active antennas and arrays are proposed and investigated. To explain the experimental results, the theory for the synchronization mechanism of oscillators is first studied. The behavior of an oscillator with an injection signal is investigated and the coupled oscillator theory is reviewed for understanding the phase variations between adjacent antennas. With the base of this fundamental theory, a new modified coupled oscillator theory for two-element active array, which discusses the effects when the two injection signals applied in the system simultaneously, will be proposed in this thesis. Next, the active microstrip antennas with feedback configuration were designed and measured. The feedback network was implemented using a two-port microstrip antenna fed and drawn by two capacitive loaded CPW’s or by aperture coupled microstrip lines. Finally, by using the results of the proposed modified coupled oscillator theory, an active microstrip antenna array with dual switching beams and a new phase shifterless beam-scanning technique were developed and demonstrated. The array contained several active antennas and an extra amplifier-embedded coupling (microstrip) line. Two injection-locking signals were used in the design, that is, the free-space mutual coupling between antennas and the injection signal on the coupling line tapped from the first oscillator in the array. By turning on and off the amplifier on the line, these two signals dominated in turn, producing two radiation modes with different main beams. A three-element H-plane array and a two-element E-plane array were designed and measured. As for the demonstration of the new phase shifterless technique, two-element active antenna array was used as an example. By mixing the effects of the signals from the control line and the mutual coupling, the phase difference between antennas is adjusted by gradually changing the amplifier bias on the control line. The measured results show that, when the control-line amplifier is biased from the off state to the fully on state, the radiation patterns for both arrays are varied smoothly from the difference pattern (with radiation phase difference) to the sum pattern (with phase difference). During the scanning process, the oscillators for each array are locked stably, with deviations of the oscillating frequencies lower than 0.35% |
URI: | http://140.113.39.130/cdrfb3/record/nctu/#NT890435099 http://hdl.handle.net/11536/67378 |
显示于类别: | Thesis |