【作者】 周良；

【导师】 刘少斌；

【作者基本信息】 南京航空航天大学 ， 通信与信息系统， 2011， 博士

【摘要】 伴随着人们对无线通信设备的要求越来越高，微波通信得以迅猛发展。便携式、小型化、抗干扰能力强等功能逐渐成为无线通信设备和终端的发展要求。作为射频前端不可或缺的一部分，滤波器和天线性能具有至关重要的作用。如何更好地缩减器件整体尺寸，控制通带带宽，调节高次谐波，抑制阻带，提高选频特性等各项指标始终是微波工作者所不断追求的目标。开环谐振器(SRR)因实现了左手材料特性而逐渐引起微波界的关注，并因其具有亚波长谐振和高品质因数的特性而成为研究热点。本文主要对开环谐振器进行了深入和广泛地应用研究。利用开环谐振器及其创新结构，结合阶跃阻抗变换、源与负载耦合、交叉耦合、零度角馈电，凋落波放大等技术，提出了多种具有新颖特性的谐振器和耦合结构，并应用在多种高性能滤波器和天线的设计中。本论文的创新性工作及成果主要包括以下几个方面：1、提出了一种新颖的阶跃阻抗开环谐振器(SIR-SRR)结构，这种结构是将开环谐振器与阶跃阻抗谐振器相互结合而构成，从而使得这种组合谐振器结构既继承了SIR的谐波可调谐优势，又具备SRR亚波长谐振的小型化特点。本文将该结构应用于交叉耦合滤波器的设计，采用这种复合结构设计的带通滤器具有小型化的特点，并表现出谐振波可抑制的特性；在此类滤波器结构基础上，通过内环谐振器上加载金属过孔，进一步设计出了具备小型化与高选择性的双频带通滤波器。2、提出了一类新型多模带通滤波器。这类滤波器采用短路分支线加载SIR结构，并结合了源与负载耦合技术，从而克服开路分支线加载SIR相对面积较大的缺点。此外，通带内被激励的多个模式表现出可以独立调谐的优越特性；采用由SIR直接折叠成的开环谐振器结构，设计出了一种仍具有高选择性的双模双频带通滤波器。3、提出一类交指电容加载的开环谐振器(CLSRR)结构，该类结构能显著地缩减滤波器整体尺寸、增大带宽，并极大地增加设计自由度。本文利用该类结构设计多款多通带带通滤波器，它们具有尺寸小、结构紧凑、低损耗，同时每个通带两侧都有一对紧靠的传输零点，具有高择性。此外，由于CLSRR结构与SRR结构组合可以构成不同的耦合方式，多个单元的这种组合结构能够实现多路通带特性。本文基于这种复合结构设计了一种结构紧凑的微带双工器，它可以在两条不同路径上分别产生不同的通带，且具有非常小的尺寸。4、将二阶互补开环谐振器(CSRR的高阶形式)作为陷波结构应用于超宽带系统，研制了几类陷波超宽带器件(天线和滤波器)。与传统的陷波超宽带器件相比，这类器件的陷波区域具有陡峭过渡带，从而提高了超宽带系统的抗干扰能力。5、将所提出的高阶互补开环器结构(CSR)与基片集成波导(SIW)相结合，设计几款小型化带通滤波器并对其进行分析。与普通CSRR和SIW组合的滤波器相比，高阶结构和SIW组合所构成的滤波器在SIW截止区域内产生了更低频率的通带，极大拓展了互补开环谐振器这类结构在SIW上设计双频多频窄带滤波器的自由度。6、采用二阶互补开环谐振器（CSR2）结构，通过同轴单点馈电，在普通微带贴片上，实现了一款极化方向不同的双频双圆极化天线。更多还原

【Abstract】 With ever-increasing demands for microwave communication systems, the wireless communicationdevices and ends with low loss, sharp transition, strong anti-interference capabilities and compact sizeare highly desired. The components including filter and antenna plays an important role in the part ofRF front end. It’s a always goal for researchers to improve these functions of microwave apparatus.The split-ring resonator (SRR) has attracted extensive attention of researchers for its novel properties.Utilizing these properties, various exotic circuits have been presented and improved. In thisdissertation, the SRR provides a particular interest, specifically for its resonant behaviors. Since theSRR can be considered as an electronically small resonator with very high Q-value, it is a very usefulstructure in constructing microwave apparatus with compact size. In this work, several kinds of theresonators based on SRR and coupling structure are presented, and different apparatus with improvedproperties are designed from the application of these resonators.The main innovations of this dissertation are as follows:1. A high selectivity quadruple-mode broadband bandpass filter (BPF) with source-load coupling isproposed using two different sizes short stub loaded stepped-impedance resonators (SIR). Two SIRscan generate four operating modes, which can be approximately adjusted individually. Owing to thespecial designs of the filter, the coupling of two resonators is weak. In each resonator, the even-modefrequency can be flexibly controlled by changing the length of the short stub in central plane, whereasthe odd-mode one remains stationary. Due to the source-load coupling, two transmission zeros areclose to the cut-off frequencies of the passband, which leads to high selectivity.2. A novel miniaturized split ring resonator (SRR) structure is introduced in designing highfrequency selectivity and stopband expanded BPF with four transmission zeros. Such fundamentalresonators consist of a pair of half-wavelength hairpin-shaped ring resonators nested in each other,which improved SRR structure. Compared with conventional SRR, this stepped impedance split ringresonator (SISRR) has better performance on miniaturization. To verify good characteristics of thenovel structure, a new resonator-embedded cross-coupled filter which is constructed by a pair of newresonators, is proposed.This novel filter is very compact and has high frequency selectivity.3. In order to provide sufficient degrees of freedom for achieving wideband of the couping filter, anovel SRR loaded interdigitail capacitor is proposed. Some coupling filters with good characteristics are designed using these resonators. Furthermore，a novel planar diplexer is developed based onsplit-ring resonators (SRRs). The proposed diplexer is comprised of three SRR, which have differentcouping style. This diplexer shows advantages in terms of the compact size, low loss, easy fabricationand integration with other circuits.4. A miniaturized CSR2is presented to improve the effect of the notch frequency for the proposedantenna and filter. Compared with CSRR, the CSR2can excite a lower central frequency resonance,when they have the same dimensions. Due to this miniaturized characteristic, the antenna can loadmultiple CSR2unit cells which generate multiple corresponding resonant modes to control the notchbandwidth and improve high frequency selectivity at the rejection frequency. Moreover, it is veryconvenient to etch SR2s slot in UWB device for band-notched. What’more, a miniaturized substrateintegrated waveguide (SIW) filter is proposed using a complementary spiral resonator (CSR). CSRtechnique can be applied to the design of miniaturized filter by increasing electrical length. Todemonstrate the idea, the miniaturized SIW filter is designed with CSR2and CSR3, respectively. Themeasured central resonant frequencies are3.25GHz and2.23GHz, which are lower than the SIW filterwith CSRR occurs at5.17GHz.5. A novel dual-band circularly-polarized microstrip antenna is proposed. The designs are based onthe complementary two turns spiral resonator (CSR2). They are the counterparts of two turns spiralresonators (SR2s), which were introduced in2004by some of the authors. CSR2s technique can beapplied to the design of miniaturized antenna by increasing electrical length. To demonstrate the idea,the proposed circularly-polarized antenna is designed to work at658MHz and2.74GHz. The gaporientation asymmetric or symmetric to the current propagating direction will render the antenna toradiate circular polarization (CP) waves with the CSR2etched on the antenna. Details of theexperimental results compared with the simulated results are presented and discussed.更多还原