【作者】 李鹏；

【导师】 陈如山；

【作者基本信息】 南京理工大学 ， 电子科学与技术， 2017， 博士

【摘要】 随着现代通信技术的快速发展,平衡式滤波电路因其优异的抗干扰、抗噪声能力在通信系统中发挥着不可替代的作用,新型平衡式滤波电路的研究与应用在现代射频/微波电路系统集成化、小型化、模块化和高可靠性的迫切需求下越来越重要。本文研究了基于基片集成波导技术的平衡式滤波电路设计原理和方法,充分利用基片集成波导低损耗、低成本、高品质因数、易于集成等优点,构建高选择性、高共模抑制、低插入损耗、小型化、高集成度的新型平衡式微波滤波电路。归纳起来,本文的创新性工作包括以下几个方面:(1)提出新型高选择性高共模抑制基片集成波导平衡式带通滤波器。采用SIW谐振腔中的两个正交简并模实现新颖的平衡馈电结构和高共模抑制,构建了具有准椭圆滤波响应的耦合拓扑结构和耦合矩阵,构造了平衡滤波器外部品质因数和内部耦合系数提取的等效模型,设计了单层单缝耦合双模平衡滤波器和双层双缝耦合双模平衡滤波器,所设计两款滤波器呈现出高频率选择性的同时分别能达到37dB和48dB的共模抑制能力。(2)提出利用基片集成波导谐振腔中平衡谐振模式构建平衡式双通带滤波器。采用矩形谐振腔中TE102模和TE201模来构建平衡滤波器的双通带,设计新颖的内部耦合结构引入源和负载之间的耦合,产生两个额外传输零点,改善了带外抑制性能。提出基于正方形基片集成波导谐振腔中对角线TE102模和TE302模构建双通带的平衡滤波器,通过调整扰动过孔的位置来改变两个通带的频比,通过在两个腔体表面蚀刻槽线来改善共模抑制性能,两个通带内的共模抑制分别达到了 55dB和50dB。(3)提出基于八分之一模基片集成波导(EMSIW)谐振器的新型小型化滤波器设计方法。构建新型馈电和耦合结构引入源和负载之间的耦合,设计了具有四个传输零点的高选择性单通带和双通带小型化滤波器。在此基础上提出了基于EMSIW的平衡式馈电谐振器,设计了基于QMSIW和EMSIW谐振器的平衡式三阶切比雪夫带通滤波器和基于EMSIW谐振器的平衡式四阶准椭圆带通滤波器,展现出紧凑的结构以及高共模抑制和谐波抑制能力。(4)提出多款新型基片集成波导平衡式滤波多功能电路。首先设计了高频率选择性平衡式滤波功分器,构造了具有准椭圆滤波响应的耦合拓扑结构,给出了耦合矩阵综合的方法,该功分器具有差模高选择性滤波响应的同时还具有很强的共模抑制能力。然后设计了基于圆形基片集成波导谐振腔的滤波魔T,该结构利用两个正交模式来实现同相和反相的功分输出,以及端口之间的隔离。最后提出一种具有非平衡到平衡转换功能的双工器,工作于双谐振模式的SIW谐振腔作为发射和接收通道的公共连接部分,既实现了滤波功能又达到了隔离效果。更多还原

【Abstract】 With the rapid development of modern communication technology,the balanced filtering circuits play an irreplaceable role in communication systems because of their high immunity to environment noise and interference.The study and application on the balanced filtering circuits have been drawn much attention with the demand of integration,miniaturization,modularization and high reliability in radio frequency/microwave circuit systems.In this dissertation,the design principles and methods of the balanced filtering circuits based on the substrate integrated waveguide technology are studied,the advantages of low loss,low cost,high quality factor and easy integration of the substrate integrated waveguide are utilized to construct novel balanced microwave filtering circuits with high selectivity,high common-mode suppression,low insertion loss,small size and high integration.The innovative work of this dissertation includes the following aspects:(1)Novel substrate integrated waveguide balanced bandpass filters with high selectivity and high common-mode suppression are proposed.Two orthogonal degenerate modes in a SIW resonator are used to realize the novel balanced feeding structure and high common-mode suppression.The coupling topology and coupling matrix with quasi-elliptic filtering response are constructed.The equivalent models for extracting the external quality factor and internal coupling coefficients of the balanced filter are built.A single-layer dual-mode balanced filter with single coupling aperture and a double-layer dual-mode balanced filter with a pair of coupling apertures are designed.The two filters are designed to exhibit high-frequency selectivity while achieving common-mode suppression of 3 7dB and 48dB,respectively.(2)The method of utilizing balanced resonant modes of the substrate integrated waveguide resonator to design balanced dual-band bandpass filter is proposed.The TE102 TE201 modes in a rectangular resonator are used to construct the dual passbands of the balanced filter.The coupling between source and load is introduced by the novel internal coupling structure,resulting in two additional transmission zeros and improved out-of-band suppression performance.A balanced filter based on the diagonal TE102 and TE302 modes in the square waveguide integrated cavity is proposed.By adjusting the position of the perturbation vias,the frequency ratio of the two passbands can be changed.Surface-etched slots are adopted to improve common-mode suppression,high common-mode suppression of 55dB and 50dB in the two passbands are realized.(3)Methods for designing novel miniaturized filters based on eighth-mode substrate integrated waveguide(EMSIW)resonators are proposed.The coupling between source and load is introduced to construct a new type of feeding and coupling structure.A single passband and a dual passband miniaturization filters both with four transmission zeros are designed.On this basis,a balanced feed resonator based on EMSIW is proposed.A single-layer balanced third-order Chebyshev bandpass filter based on QMSIW and EMSIW resonators,and a double-layer balanced fourth-order quasi-elliptic bandpass filter based on EMSIW resonators are designed,respectively.Both exhibit compact structures,high common-mode suppression and harmonic suppression.(4)A series of novel substrate integrated waveguide balanced filtering multi-functional circuits are proposed.Firstly,a balanced filtering power divider with high selectively is designed,a coupling topology with quasi-elliptic filtering response is constructed,and coupling matrix synthesis method is presented.The power divider displays high selective filtering response under differential-mode operation and high suppression under common-mode operation.Then,a filtering magic-T based on a circular substrate integrated waveguide resonator is designed.Two orthogonal modes are used to realize in-phase and out-of-phase outputs and the isolations between sum and difference ports,and two power-dividing ports.Finally,a unbalanced-to-balanced diplexer is proposed.The SIW resonant cavity working in dual-resonant modes is utilized to construct the common connection part of the transmitting and receiving channels,filtering response and isolation are achieved.更多还原