平坦通带高频纵向耦合谐振滤波器的研制

应用耦合膜理论,重点研究了纵向耦合谐振滤波器耦合换能器与输入/输出换能器间距对纵向耦合谐振滤波器通带波纹的影响,探讨了制作纵向耦合谐振滤波器中金属铝的干法刻蚀工艺。基于理论模拟得出的结论,文中给出了中心频率为900MHz纵向耦合谐振滤波器频率响应的计算模拟结果和实验测试数据。测得1dB带宽25.9MHz,3dB带宽28.7MHz,阻带抑制达到50dB,插入损耗3.85dB,通带波纹小于0.7dB。实验结果与理论分析相吻合。     

基于并联耦合线谐振节的窄带带通滤波器的研究

设计了一种基于并联耦合线谐振节的窄带带通滤波器。该滤波器由常见平行耦合线带通滤波器与并联耦合线谐振节构成。利用并联耦合线谐振节结构的特性,借助ADS软件设计了一个中心频率为4.9 GHz的窄带带通滤波器。仿真结果表明,其3 dB带宽为236 MHz,矩形系数为2.8。该滤波器具有良好的带外抑制能力和更加陡峭的通带到阻带过渡。     

微声薄膜耦合谐振滤波器的仿真与设计

基于Mason模型,建立了微声薄膜耦合谐振滤波器的等效电路,实现了滤波器的快速仿真设计。将耦合谐振滤波器与梯形结构微声薄膜滤波器级联,改善了滤波器的矩形度、带外抑制等特性,并通过优化设计,提高了级联滤波器的相位线性度。     

微声薄膜耦合谐振滤波器有限元建模与仿真

针对一维等效电路仿真模型不能对滤波器振动模式进行仿真的局限性,建立了微声薄膜耦合谐振滤波器二维和三维的有限元模型,仿真分析了滤波器在对称谐振频率和反对称谐振频率下的振动模式,并通过频率响应分析得到了滤波器的S参数.仿真结果表明,采用有限元分析法可实现微声薄膜耦合谐振滤波器几何参数以及电极结构的优化设计.     

平行信道串联多环谐振滤波器的箱形波谱响应

对平行信道串联多环谐振滤波器的传输特性进行了理论分析，给出了其光学传递函数公式。在谐振波长为1．55μm情况下，对其滤波特性进行了数值模拟。计算结果表明，选取串联微环数为4、信道与微环间的振幅耦合比率为0．25以及相邻微环间的振幅耦合比率为0．022时，箱形波谱响应即可形成，其3dB带宽约为0．2nm，谐振光的插入损耗约为1．5dB，非谐振光的最小值已接近-150dB。     

声表面波纵向耦合谐振滤波器通带特性研究

在理论方面,作者应用COM理论分析研究了纵向耦合谐振滤波器通带波纹大小和耦合换能器与输入/输出换能器间距离的关系。在工艺上,作者采用剥离工艺制作了相应的纵向耦合谐振滤波器,并给出了所设计的纵向耦合谐振滤波器频率响应的测试结果。实验测得样品滤波器中心频率为895 MHz,1 dB带宽40.5 MHz,阻带抑制达到47 dB,插入损耗3.8 dB,通带波纹小于0.9 dB。实验与理论分析比较一致。     

低插损极窄带声表面波滤波器设计

利用集总参数等效电路模型计算了声表面波双模耦合谐振滤波器的频响．通过改变谐振器各个参量使滤波器指标满足要求．在ＳＴ石英基片上成功研制出中心频率２２８ＭＨｚ，△ｆ－３ｄＢ＝１５０ｋＨｚ，插损为３ｄＢ，阻带抑制小于－５０ｄＢ的铁路专用寻呼机用滤波器。理论计算与实验结果一致。     

C波段LTCC宽边耦合叠层滤波器设计

C波段LTCC带通滤波器的设计,由于其谐振器采取集中LC元件,其Q值偏低,且LTCC厚膜集中元件大小在C波段相对偏大,为此在设计方面主要考虑利用传输线结构的分布参数谐振单元。分布参数宽边耦合谐振单元耦合系数大,特别适合中宽带滤波器设计。文章根据滤波器指标要求,通过电路综合出滤波器的耦合系数及外部Q值。然后利用LTCC多层优势,实现宽边叠层耦合谐振单元的C波段滤波器。     

一种基于正方环形谐振器的新型宽带带通滤波器

本文设计了一种紧凑型、宽通带、宽阻带的微带带通滤波器。该滤波器的设计是基于带有两个开路调节支节的正方谐振环。基于紧凑性的考虑,改变了传统方环谐振滤波器的馈电点和开路调节支节的位置,以便对谐振环进行折叠处理。这种改变并不影响谐振环的奇偶模特性。在输入和输出端口,通过两个叉指耦合结构对滤波器进行馈电,这种馈电方式增加了滤波器阻带的带宽和抑制度。滤波器的中心频率为4GHz,相对带宽为45％,通带内的回波损耗小于-12dB,群时延小于0．8ns,1-2．9GHz阻带抑制度大于12dB,5．3～7GHz阻带抑制度大于18dB。     

耦合谐振带通滤波器带外特征及应用

耦合谐振带通滤波器在通信系统的设计过程中起着至关重要的作用.通过分析带通滤波器的设计原理,给出具体耦合谐振带通滤波器的设计实例,比较了电感耦合与电容耦合带通滤波器带外特性的区别.通过利用电感耦合与电容耦合带通滤波器带外特性的这一区别,可以使双工器的设计结构更加简单,实现更加方便,性能更加优越,同时可以使利用更少阶数,更简单的结构设计出性能指标相同的带通滤波器.     

Compact ultra-wideband bandpass filter using harmonic-suppressed multiple-mode resonator

A compact ultra-wideband bandpass filter with good upper-stopband performance is presented. A wide stopband above the desired passband is realised relying on three transmission zeros of capacitive-ended parallel coupled lines. A modified multiple-mode resonator is formed with a self-contained stopband. By linking this resonator with two interdigital coupled lines, an ultra-wideband bandpass filter is constituted. Predicted results are verified by experiment in a frequency range of DC to 25 GHz.     

Compact Dual-Band Filter Using Defected Stepped Impedance Resonator

This letter presents a novel approach for designing a dual-band bandpass filter by using defected stepped impedance resonator (DSIR). The resonant frequency of the DSIR is found to be much lower than that of the conventional microstrip stepped impedance resonator (SIR), which reduces the circuit size effectively. Two types of second-order DSIR microstrip bandpass filter operating at 1.85 and 2.35 GHz, respectively, are well designed according to the classical theory of coupled resonator filter. Then they are combined to construct a compact dual-band filter with a common parallel microstrip feed line, the measurement results of the fabricated filter have a good agreement with the simulation.     

一种新型广义交叉耦合滤波器的设计

含广义交叉耦合的N个谐振器滤波器,即含源-负载交叉耦合的滤波器能产生N个传输零点,通过给出这种滤波器的等效网络模型和传输函数,设计了两种新颖六边形结构的含源-负载交叉耦合的微带滤波器,一种为对称结构,一种为非对称结构.对其进行了仿真分析,仿真结果与理论值吻合较好.与传统两腔发夹形滤波器相比,这种两腔六边形结构的滤波器尺寸要缩小27.5%,频率选择性更高.     

波导微环共振滤波器的滤波特性分析

根据波导耦合模理论详细研究了微环共振滤波器的滤波特性,分析了单环、串联双环、串联三环结构等波导微环共振滤波器的滤波特点。通过模拟计算发现,滤波带宽平坦化程度和信道串扰大小主要依赖于由波导构成的各方向耦合器之间的功率耦合比k,同时微环波导的损耗是器件滤波特性劣化的重要原因。在一定优化参数条件下,多环结构的滤波效果优于传统单环结构,并且各方向耦合器功率耦合比k值的优化取值范围扩大,降低了器件工艺实现难度。     

Temperature insensitive vertically coupled microring resonatoradd/drop filters by means of a polymer overlay

The temperature dependence of vertically coupled glass microring resonator add/drop filters is investigated. Measurements show that the passband of the air-clad microring resonator filter increases with temperature at a rate of 0.0137 mm/°C. Using a PMMA-TFMA polymer that has an opposite refractive index temperature gradient than glass as the overlay of the microring resonator, the temperature dependence of the filter is compensated to -0.0025 nm/°C in the operation range of 25°C to 55°C     

X波段SIW广义切比雪夫超结构滤波器设计

基于基片集成波导设计了一种正交分裂环谐振器,并证明了该谐振器具有双负特性。将该超结构放置于双层基片集成波导中,得到了具有频率选择特性的四端口耦合结构。将加载正交分裂环谐振器的耦合结构与广义切比雪夫滤波器相结合,设计了一种X波段SIW广义切比雪夫超结构滤波器。仿真结果表明,设计的滤波器满足了中心频率为10.519 GHz、相对带宽为0.25%、通带内的插入损耗小于-1 dB、回波损耗小于-20 dB的技术指标。     

A Novel Dual-Mode Dual-Band Bandpass Filter Based on a Single Ring Resonator

A dual-mode dual-band bandpass filter with two transmission poles in both passbands using a single ring resonator is proposed. Two excited ports are placed at the 135$^{circ}$ -separated positions along the ring resonator and coupled with the ring via parallel-coupled lines, leading to synchronous excitation of two transmission poles in dual passbands. After the principle of this initial filter is described, an improved ring resonator with periodic loading of open-circuited stubs is constructed and studied to achieve compact size and adjustable spacing between the two passbands. Finally, a dual-band ring resonator filter with center frequencies at 2.4 and 5.8 GHz is designed and fabricated. Measured results verify the design principle.      

Microstrip bandpass filters with reduced radiation effects

The realisation of a microstrip bandpass filter employing coupled hairpin-line resonators is discussed. The performance of an experimental filter at 11 GHz confirms that the low-radiation property of the hairpin resonator leads to improved behaviour compared with a coupled-resonator filter o conventional form.     

Microstrip Interdigital Hairpin Resonator With an Optimal Physical Length

In this letter, we report a novel microstrip interdigital hairpin resonator by having the parallel coupled lines in a conventional miniaturized hairpin resonator replaced by an interdigital capacitor. Equations are derived in order to design the resonator with an optimal physical length. It will be proved that the novel resonator can achieve even more size reduction than the conventional miniaturized hairpin resonator owing to the employment of the slow-wave structure. Finally, a four-pole cross-coupled bandpass filter using the optimal resonator is fabricated as verification