【作者】 郑博仁；

【导师】 赵志钦；

【作者基本信息】 电子科技大学 ， 电磁场与微波技术， 2012， 博士

【摘要】 随着通信技术的发展，人们对高速无线移动通信的需求变得越来越强烈，使得频谱资源变得越来越紧张，同时用来实现频带划分、频带隔离的关键器件滤波器的参数要求也变得越来越严格，为了满足高传输速率，滤波器的工作频率也相应的变得越来越高，带宽也越来越宽。基片集成波导（SIW）滤波器因具有重量轻、体积小、成本低、可工作于高频率、便于与平面电路集成以及可方便的利用标准的PCB技术和LTCC技术加工等独特的优点，成为在无线高速移动通信中的首选。但是，基片集成波导也具有一些限制其应用的缺点：由于基片集成波导采用金属线阵来实现波导壁，存在一定的间隙，容易引起能量的泄漏，导致滤波器的带外抑制性能变差，在宽带情况下更为严重；基片集成波导多为矩形波导，其输入输出的位置相对固定，不能满足移动设备中复杂的安装环境；基片集成波导实质上是介质填充的波导，介质具有一定的损耗，导致谐振器Q值降低，频率越高滤波器带内衰减将越大；同时在基片上采用PCB和LTCC技术，公差的绝大部分都是在过孔的电镀过程产生的，而基片集成波导采用金属过孔来实现滤波器的波导壁和耦合结构，加工的精度对器件的性能将直接产生影响。这些缺点极大地限制了基片集成波导的应用与推广。为了推进基片集成波导滤波器在无线通信中的使用，弥补基片集成波导的缺点，论文就如何提高基片集成波导微波滤波器性能进行了研究。主要研究工作包括：1、对基片集成波导衰减特性、三种常用的输入输出馈电方式：微带、渐变线、开槽耦合以及其对应的尺寸敏感度进行了分析，得到了其相应的传输特性和尺寸容差特性。同时，对采用耦合谐振腔综合宽带滤波器理论进行研究，为设计宽带高性能滤波器打下基础。2、为了满足如卫星通信、移动设备等通信系统和设备对系统集成结构上的需求，论文对圆柱基片集成波导的特有电磁特性进行分析，利用圆柱基片集成波导中圆对称分布的TM01模，设计实现了高安装性能的宽带滤波器，具有非常灵活的输入输出设置性能；对基片集成圆柱波导中特有的双模工作模式进行了分析，就如何选用级间耦合结构来实现双模非对称响应滤波器进行了研究，得到了这类滤波器实现级间耦合的方法。3、论文对如何改善基片集成波导滤波器的带外抑制性能进行了研究，提出了采用旁路耦合圆柱谐振腔在滤波器带外产生传输零点的方式来提高滤波器带外抑制性能的方法：当基片集成旁路耦合圆柱谐振腔高和半径之比满足：h/R <2.04时，圆柱谐振腔内TM01成为唯一的工作模式，谐振腔谐振频率只与半径和高度相关，当高度固定则可以用半径来唯一控制谐振频率，引入该旁路耦合圆柱谐振腔进入滤波器的倒相器也具有频率独立特性，因此，利用旁路耦合圆柱谐振腔在基片集成波导滤波器中任意位置便可设置传输零点。另外，论文还对基片集成半模波导结构进行了分析，利用大尺寸半模基片集成波导中双模旁路交叉耦合来产生传输零点，设计了一种具有带外传输零点的双模大尺寸半模结构滤波器，改善了该滤波器的上边带性能。4、论文还对基片集成椭圆波导的电磁特性进行了分析，利用基片集成椭圆波导的独有特性：椭圆腔中不会因为横截面的轻微不连续和开口而产生模式分裂和极化旋转，提出了一种采用椭圆波导来设计实现低加工尺寸灵敏度的滤波器的方法，设计实现了一个具有高的加工工艺尺寸容差椭圆基片集成半模滤波器，结果验证了该方法的正确性。通过对上述内容的研究，得到了一些设计高性能的基片集成波导微波滤波器的有效方法。更多还原

【Abstract】 With the development of the communication technology, demand of the high speedwireless mobile communication becomes more and more intense, and the spectrumresource is shortage increasingly. The filter, as the key device of band allocation andchannel isolation, is supposed to with stringent selectivity, low insertion, and potentialintegration into the circuit for high frequency and wide band application. Substrateintegrated waveguide (SIW) filter provides a low-cost, low-weight, easy for highfrequency and wide band application, simple fabrication with the PCB<CC andpossible integration scheme while maintaining high performance, which is satisfied withthe needs perfectly. But the discontinuities in the post wall of the SIW lead to poorstopband attenuation of SIW filter; the filter’s I/O setting is limited by the rectangularwaveguide; substrate dissipation causes a loss in the SIW resonator Q value, higher thefrequency, lower the Q value, the Q descending make the filter selectivity to deteriorate;moreover, the position tolerance of plated via-holes is usually several times thetolerance of trace sizes in PCB or LTCC, the fabrication tolerance directly influencefilter designing, optimizing and final performance. These disadvantages limit theapplication of substrate integrated waveguide greatly.With the purpose of promoting SIW filters application in the wirelesscommunication, many improve SIW filter performance technology are studied in thisthesis. The main research works include as follows:1. Three popular I/O modes for SIW filter include microstrip, taper, slot couplingand their size sensitivity, and the dispersion characteristics of SIW are analyzed. Thetransmission characteristic of SIW and the size sensitivity features of the three I/Omodes are got. Furthermore, the broadband coupling resonant cavity filter synthesizetechnology is studied. The results can be used to facilitate the synthesizing of highperformance broadband coupling resonant cavity filter.2. The electromagnetic characteristics of substrate integrated circular waveguide(SICW) are presented in this thesis. In order to meet the needs of the system installationand integration, such as satellite communications and mobile equipment, based on the circular symmetry TM01mode in SICW, a high performance wideband filter the withflexibility I/O structure is designed. Additionally, the coupling structure of the dualmode in the SICW filter are researched also, and asymmetric responding filters withimprovement upper stopband performance are obtained.3. A method to improve filter upper stopband performance using bypass couplingsubstrate integrated circular cavity resonator (BC-SICCR) is presented. Using SICCR asthe bypass coupling resonator, its resonant frequency can be entirely controlled by theSICCR radius (when height is fixed) owing to theTM01mode is selected as only theoperating mode while the SICCR height h and the radius R meet with h/R <2.04. Dueto the operating mode is exclusivity in SICCR, this structure of the inverter with SICCRbrings the bypass coupling of the SICCR in the SIW is independent of frequency,transmission zeros can be set up at arbitrary place in filter stopband through theBC-SICCR. Besides, a technique of bypass cross coupling through higher/lower orderdual mode in one SIW to produce a transmission zero is presented, and it is verified bya oversized dual mode folded half mode SIW filter with bypass cross couplingtransmission zeros.4. The electromagnetic character of the elliptic substrate integrated waveguide isstudied. A novel half mode elliptic substrate integrated waveguide (HMESIW) filterwith a good performance in tolerance sensitivity is proposed and fabricated by usingstandard PCB technology. Due to the advantage of elliptical waveguide cavity, no modesplitting or rotation of the polarization plane at the condition of slight deformations incross section, the tolerance sensitivity of the filter sizes is reduced. The measured resultsdemonstrate the HMESIW filter has a superior performance in tolerance sensitivity.Through the above-mentioned researchs, the results can be boosted the design ofhigh performance SIW microwave filter.更多还原