基于QMSIW小型化带通滤波器设计

为有效减小X波段基片集成波导(SIW)滤波器的尺寸和插入损耗,提出了基于四分之一模基片集成波导(QMSIW)和共面波导(CPW)混合结构的小型化带通滤波器。为了提高滤波器的选择性和带外抑制,将两个CPW合并到两个级联的QMSIW谐振器中,由于两个CPW谐振器之间的耦合是电耦合,有助于产生两个传输零点,因而具有较高的选择性。该小型化滤波器尺寸仅为8.1 mm×15.4 mm,中心频率为8.7 GHz,相对带宽是16.1%,仿真测得插入损耗为0.83 dB,带外抑制大于40 dB。     

基于DGS 结构的微带岔线型带通滤波器设计

本文介绍了一种基于缺陷地结构(DGS)的微带岔线型宽带带通滤波器的设计过程。此滤波器以四分之一波长的开路枝节型带通滤波器为原型进行设计和改进,引入了微带岔线和DGS 结构,在增加通带带宽和阻带带宽的同时,使滤波器的带外谐波抑制和带内回波损耗得到了很大的改善。采用HFSS 三维场仿真软件进行S 参数的仿真,从仿真结果可 以看出,所设计的带通滤波器中心频率为11.5GHz,其3dB 相对带宽大于50%,带内插损小于0.3dB。此外,在1-6GHz的第一阻带内,滤波器的带外抑制大于20dB,最大抑制度为52dB;在15-24GHz 的第二阻带内滤波器的带外抑制大于20dB,最大抑制度为46dB。整个滤波器尺寸仅为12mm × 16mm。     

一种共面波导结构双模方形贴片带通滤波器

提出一种新型共面波导(CPW)结构双模方形贴片带通滤波器。该滤波器采用方形贴片作为谐振器,在方形贴片的两个对称的角上开两个相同的方形切角作为微扰使其简并模式分离并产生耦合,贴片与输入/输出CPW分别设计在介质基板的两个不同的面上。文中给出了该滤波器的结构以及通过仿真和实验获得的性能参数,结果表明该滤波器的通带带宽可在4.9%到7.4%的范围内调节,通带内的最小插入损耗为1.85dB。     

基于LCP基板的超宽带滤波器的设计与实现

高分子液晶聚合物(LCP)以其优异的高频特性,被认为是继低温共烧陶瓷(LTCC)后的下一代微波毫米波的基板和微组装材料。本文基于五层LCP基板设计了一款超宽带(UWB)带通滤波器(BPF),采用四分之一波长线来替换半波长的MMR结构,并且通过折叠传输线的方法进一步缩小BPF滤波器的体积。利用HFSS仿真软件对滤波器进行了建模仿真。通过标准的LCP多层工艺,制备了超宽带滤波器。测试结果表明,在2.5 GHz到10.4 GHz的频带范围内,插入损耗优于-5 dB,回波损耗小于-15 dB,带外抑制高于-30 dB。其测试结果和仿真结果能够较好地吻合。该滤波器的成功设计为超宽带通信系统的小型化提供了一个重要的参考。     

一种0.18μm CMOS毫米波带通滤波器的设计

基于SMIC 0.18μm RF-CMOS工艺,设计了一种采用垂直地平面共面波导(VGPCPW)传输线的片上30 GHz带通滤波器。通过对传统CPW和VGP CPW两种不同结构传输线的理论研究,对比分析了两者的损耗、特征阻抗及隔离特性,建立了VGP CPW长度可扩展的传输线模型。使用特征阻抗为50Ω的低损耗VGP CPW传输线结构,结合VGP CPW长度可扩展模型与EM分析方法,设计了30 GHz带通滤波器。在片测试结果表明,该毫米波VGP CPW传输线滤波器模型仿真和电磁场仿真S参数曲线与测试结果比较吻合,可为毫米波集成电路滤波器设计提供借鉴。     

基于EMSIW-QMSIW小型化带通滤波器设计

为有效减小S波段基片集成波导(Substrate Integrated Waveguide,SIW)滤波器的尺寸和插入损耗,提出了一种基于四分之一模基片集成波导(Quarter-Mode Substrate Integrated Waveguide,QMSIW)和八分之一模基片集成波导(Eighth-Mode Substrate Integrated Waveguide,EMSIW)交叉排列耦合的小型化带通滤波器;并针对提高滤波器选择性和带外抑制水平,通过设计源与负载耦合,实现传输零点的引入。设计了一款小型化带通滤波器,中心频率为3.7 GHz,相对带宽为18.9%,仿真测得最小插入损耗为0.55 dB,带外抑制大于40 dB,且标准化尺寸仅为0.24λ_0×0.11λ_0。通过制作实物验证,测试与仿真相吻合。     

CMOS低中频有源复数带通滤波器设计

设计并实现了基于0.18 μm CMOS工艺的2.4 GHz无线传感网(Wireless Sensor Network)射频接收机低中频有源复数带通滤波器.该滤波器采用基于积分器单元的复数带通滤波器结构,同时实现镜像抑制和信号滤波的功能.仿真结果表明,复数带通滤波器的中心频率为2 MHz,通带带宽为2.4 MHz,通带电压增益约为12.5 dB,镜像抑制大于30 dB,相邻信道阻带衰减大于40 dB,噪声系数小于15 dB,消耗电流为5 mA.通过系统验证,本设计各项性能均满足无线传感网射频接收机的设计要求.     

一种缺地陷结构超宽带滤波器

提出一种应用缺地陷结构的小型微波超宽带滤波器。该滤波器由四分之一波长短路支节线和哑铃形缺地陷结构构成。结构正面的四分之一波长短路支节线实现该滤波器的高通特性,结构反面的哑铃形缺地陷结构构成高端阻带。文中给出了该滤波器的结构以及通过仿真和实验获得的性能参数,结果表明该滤波器的带宽为2.2~10GHz,在2.8～9.5GHz的通带内的插入损耗小于1.8dB,在4.5~9.5GHz的通带内的回波损耗大于15dB,中心频率的群时延为0.45ns,整个通带内群时延小于0.65ns。     

114.3~123 GHz六阶带通滤波器设计

基于经典的半波长滤波器理论,设计了一种用于太赫兹通信系统的半波长磁耦合矩形波导带通滤波器。仿真结果表明,该滤波器中心频率为118 GHz,通带为114.3~123 GHz,相对带宽为7.4%;在131.8 GHz处的抑制度大于30 dB,通带插入损耗小于0.8 dB,通带回波损耗大于20 dB。经过实物测试,测试结果与仿真结果基本一致。这种滤波器的结构简单,制作难度低。     

高选择性发夹型带通滤波器的设计

微带发夹型带通滤波器具有尺寸小、结构简单、性能稳定等优点,在射频微波领域有着广泛的应用。 本文使用ADS 软件设计仿真了一种高选择性抽头式发夹型带通滤波器。与一般发夹型滤波器相比,该滤波器在输 入输出端并联四分之一波长开路微带线,通过在寄生通带增加传输零点的方法提高滤波器的带外抑制性能。另外, 在该滤波器的谐振单元上增加并联阶跃阻抗枝节,在通带两侧产生一对传输零点,来提高该发夹型带通滤波器的选 择性。最后对这种高选择性发夹型带通滤波器进行实物加工,测试结果证实了该带通滤波器的良好选择性能。     

一种S波段小型宽带微带带通滤波器优化设计

基于并联短截线谐振器与联接线变换器构成的传统微带带通滤波结构,提出了一种工作在S波段的改进型宽带带通滤波器。以三阶结构为例,通过将两侧并联短截线进行弯折,形成耦合线结构;将中间并联短截线进行拆分,变为并联的短路线和开路线,实现了在通带性能基本不变的前提下,获得阻带可调控的传输零点,进而提高过渡带陡峭度。为了进一步抑制阻带,在滤波器两侧级联扇形微带低通滤波结构,改善阻带性能。利用ADS和HFSS仿真软件对滤波器结构进行仿真优化设计,并最终进行了实物加工和测试。实测结果表明,通带内2~4 GHz插入损耗小于0.7 dB,回波损耗大于17 dB,通带外4.6~6.5 GHz 阻带抑制达到20 dB 以上。     

宽阻带小型化双频带通滤波器

文中提出了一种具有宽阻带的紧凑型双频带通滤波器,它采用了折叠短路枝节负载谐振器、紧凑型微 带单元谐振器(CMRC)和阶跃阻抗谐振器结构。由于多个谐振器产生了五个可控传输零点(TZ),该滤波器实现了两个 通带之间的良好隔离度以及宽阻带特性。制作并测试了尺寸紧凑的双频带通滤波器实验样品,测试结果显示,第一通 带和第二通带的中心频率/ 插入损耗分别为0. 66 GHz/0. 8 dB 和1. 73 GHz/0. 7 dB,阻带频率高达10. 5 GHz,抑制水平 超过15 dB。     

A silicon micromachined four-pole linear phase filter

A 27-GHz four-pole linear phase filter constructed of micromachined cavities in silicon is presented. The structure of the filter consists of four side-by-side horizontally oriented cavities, which are coupled in turn by evanescent waveguide sections with three direct-couplings and one cross-coupling between the first and fourth cavity resonators. The cavities are reduced-height waveguide resonators and are fed by microstrip lines through slot apertures. A time-domain tuning technique is employed to improve the efficiency of the design synthesis. The measured results are presented and compared to those predicted by a finite-element-method model. The simulated filter response has a bandwidth of 2.2% centered at 27.480 GHz with an insertion loss of 1.4 dB at that frequency. The measured performance indicates a 1.9% bandwidth centered at 27.604 GHz with a deembedded insertion loss of 1.6 dB at that frequency and a measured unloaded Q of 1465.     

Performance improvement and size reduction of microstrip dual-mode bandpass filter

A novel miniaturised dual-mode bandpass filter with multi-arc resonators is proposed. The size of the dual-mode filter can be reduced significantly by using the microstrip dual-mode resonator consisting of multi-arcs; meanwhile insertion loss and spurious response suppression are improved A prototype filter is designed and implemented at 3.6 GHz with 2.8% fractional bandwidth, which shows a low passband insertion loss of 1.02 dB and a wide stopband with rejection better than 20 dB up to about 8.5 GHz.     

Design of low-pass filter with 3-interations Koch fractal Pi-shaped DGS

A novel asymmetrical Pi-shaped defected ground structure (DGS) with 3-interations Koch fractal curves is proposed to design a microstrip low-pass filter (LPF) with ultra-wide stop-band (SB). The proposed LPFs with a single resonator and two cascaded resonators are both designed, simulated, manufactured and measured. Simulation and experiment results demonstrate that the designed LPF has a very sharp transition band (TB) and an ultra-wide SB performance compared with the existed similar symmetrical and asymmetrical DGS. The proposed LPF with two cascaded resonators is with a compact size of 36.8 mm×24.0 mm, a very low insertion loss of less than 0.7 dB under 1.9 GHz, and a wide SB from 2.2 GHz to 8 GHz with rejection of larger than 30 dB.     

基于枝节加载谐振器的新型三频带通滤波器设计

提出了一种新型平面三频带通滤波器,该滤波器由一个加载短路枝节的阶梯阻抗谐振器,一对加载开路枝节的背靠背E型谐振器,以及包含源负载直接耦合的馈电结构组成.所采用的枝节加载谐振器的多模工作特性使滤波器的体积大大减小,同时每个通带的位置及其耦合特性都能够独立调谐.另外,通过源负载直接耦合引入通带两侧的传输零点,实现了滤波器良好的频率选择性.最后设计并加工了一款高选择性小型化三频带通滤波器,其三个通带的中心频率分别为2.0GHz,3.95GHz和6.35GHz,插入损耗均小于2.5dB,带内回波损耗均优于14dB,实验结果与仿真结果吻合良好.     

Development of new miniaturised bandpass filter having ultrawidebandwidth

A new, compact, very-broadband bandpass filter, consisting of two-parallel-conductor short-circuited spurline resonators, quarter-wavelength long, is described. Approximate design formulas for the filter are derived. The chain matrix of the resonators is also obtained and used in predicting the filter response. It is found that this filter possesses a very wide bandwidth, more than 5:1. A microstrip filter having a passband from 1.8 to 9.2 GHz has been designed and tested with less than 1 dB insertion loss. There is also a reasonably good agreement between the experimental and theoretical performances. The developed filter is very attractive for wideband microwave integrated circuits due to its compactness and very wide bandwidth     

小型化宽频带宽阻带微带滤波器的设计

目前研究宽频带微带滤波器的文献很多,但普遍不能同时具有宽频带和宽阻带的性能,且带内回波损耗大,带外抑制差。为此,提出了一种新型的宽频带微带滤波器。该滤波器采用在E型阶跃阻抗谐振器( SIR)中引入U型结构的方法,实现其宽频带宽阻带的性能。对滤波器进行仿真、加工与实测,仿真结果与实测结果吻合良好。加工得到的滤波器3 dB带宽为7.1 GHz,低于-20 dB的高频阻带为9.3 GHz,带内回波损耗低于-23.2 dB,实物尺寸为15 mm伊8.5 mm,具有小型化的特点。实测数据表明,提出的滤波器具有良好的性能,在工程领域具有实际的应用价值。     

A vertically integrated micromachined filter

A 10-GHz filter constructed of slot-coupled micromachined cavities in silicon is presented. The novel character of the filter lies in its structure, which consists of a microstrip feed to cavities via slot apertures and three vertically stacked slot-coupled cavities. The cavities are essentially reduced-height waveguide resonators. The measured results are presented and compared to a finite-element-method model. The simulated model has a bandwidth of 4% with an insertion loss of 0.9 dB at 10.02 GHz. The measured filter yields a 3.7% bandwidth with a deembedded insertion loss of 2.0 dB at 10.01 GHz. Various loss mechanisms are examined to explain the difference between simulated and measured insertion loss     

基于波纹耦合微带线的可调谐带通滤波器

设计了一种紧凑5阶双零点可调谐带通滤波器。通过在传统梳状线滤波器中引入波纹耦合微带线结构,该滤波器可以在中心频率调谐过程中保持绝对带宽恒定,同时尺寸相较于传统方法可减小50%。谐振器中引入分布式补偿电容利于滤波器应用于高介电常数衬底的微带线结构。基于源与负载间的耦合,引入两个传输零点来提高滤波器的衰减特性。HFSS仿真结果显示,当加载的电容值为2.43 pF时,滤波器的中心频率为1.48 GHz,带宽为194 MHz,插入损耗为1.36 dB。随着加载电容值从2.15 pF增加到2.93 pF,滤波器的中心频率从1.55 GHz减小至1.37 GHz。保持绝对带宽恒定的情况下,通带内的插入损耗小于1.5 dB。