带DGS的互补型传导传输线双模滤波器

介绍了一种带有缺陷地结构的互补型传导传输线带通滤波器结构,并对其进行了电磁仿真,得到比较好的结果.该结构在使用环形谐振器缩小器件尺寸的基础上,引入互补型传导传输线,使得滤波器保持性能良好的基础上进一步缩小尺寸."螺旋"形DGS结构用来抑制谐波效应,使得带通滤波器的整体性能得到显著优化.该滤波器在中心频率915 MHz处回波损耗达到20.5 dB,通带内最小插入损耗为1.9 dB,3 dB带宽为52 MHz.该带通滤波器便于在微波集成电路中使用,有利于实现设备的小型化.     

一种新型L波段带通滤波器的设计

本文给出了一种具有平行耦合线分裂环谐振器式Ｌ波段带通滤波器的近似设计方法及实验结果。这种滤波器结构简单，宜用于微波单片集成电路。     

基于双同轴阶梯阻抗谐振单元的平衡带通滤波器北大核心CSCD

本文介绍了一种基于阶梯阻抗谐振器(SIR)的双同轴谐振单元(TCR),并基于此构建了一个具有宽阻带和高共模抑制能力的二阶平衡带通滤波器。双同轴谐振器的单腔由两个阶梯阻抗谐振器构成。在这种情况下,基模用于构建差分通带,而第二个模式则用作共模抑制。本文主要提出了一个二阶带通平衡滤波器,该滤波器中心频率为1.17GHz,插入损耗为0.18 dB,3-dB相对带宽为6.3%,共模抑制超过65 dB。此外,谐波出现的位置约为基模频率的3.7倍,优于普通同轴谐振器的谐波水平。     

一种具有陡峭边带的宽带带通滤波器设计

基于一种新型的多模谐振器设计了一款宽带带通滤波器,该多模谐振器由鱼骨形谐振器及中心加载倒T形谐振器构成。滤波器的中心频率位于2.47 GHz,相对带宽为100%。滤波器具有极高的频率选择性,其边带滚降速度分别为232 dB/GHz和168 dB/GHz。此外,滤波器还具有较低插入损耗0.4 dB,紧凑的电路尺寸以及宽阻带抑制能力。     

基于新型互补开环谐振器的带通滤波器

展示了一种新型互补开环谐振器(Complementary Split Ring Resonators,CSRR).文章分析了CSRR的运行机理,研究了环缝的半径、径向间距对带通滤波器性能的影响,将该结构用于一个三阶波导带通滤波器的设计.并采用有限元法对这种结构的传输特性进行了仿真.仿真结果表明,所设计的波导带通滤波器带宽满足指标700 MHz,中心频率10 GHz,插损0.5 dB,具有体积小、性能高的特点.     

基于圆头谐振器的低插损带通滤波器设计

针对插入损耗高和选择性低等问题,提出了一种具有圆形开路终端的新型谐振器拓扑结构。该结构将传统的U型发夹滤波器改成V型,在V型结构的终端引入圆形开路谐振器,并在开路枝节短截线上过孔。基于新型谐振器结构设计了一款尺寸为42.9 mm×36.54 mm (0.35λ_g×0.3λ_g)的带通滤波器。该滤波器具有插入损耗低、通带可控和远端优良等优点,并且采用新型谐振器之间的交叉耦合,在近端1 GHz附近产生一个传输零点,有效优化了阻带抑制和带通滤波器的选择性。仿真结果表明,带通滤波器的中心频率为1.7 GHz, 3 dB的相对带宽为20%,最大回波损耗优于30 dB,最小插入损耗为0.20 dB,左边的带外抑制在50 dB以下,右边的带外抑制优于20 dB。实物测试结果与仿真结果基本一致,整体性能偏好,证明了该结构的可行性。     

基于圆端ASIR的紧凑型带通滤波器设计

为满足现代通信系统对滤波器电路尺寸和滤波性能的需求,提出了一种基于微带传输线的紧凑型带通滤波器。该滤波器采用折叠开环的圆端非对称阶梯阻抗谐振器(Asymmetric Stepped-Impedance Resonator, ASIR),实现了紧凑的电路结构;利用谐振器与馈电结构间的交叉耦合引入两个传输零点,提高了滤波器的通带选择性和阻带抑制性能。基于以上思路,设计了一款尺寸为22.7 mm×12.4 mm的带通滤波器。该滤波器中心频率为2.51 GHz,相对带宽为13.5%,回波损耗S₁₁优于25 dB,带内插入损耗S₂₁低于0.44 dB,阻带抑制优于30 dB。对滤波器进行加工测试,实测结果与仿真结果基本一致,验证了该方案的有效性。此外,该滤波器还具备结构简单、易于集成等优点,有利于通信系统的频率选择和集成化使用。     

360MHz声表面波带通滤波器的研制

本文简要介绍了360MHz声表面波带通滤波器的研制,设计原理、思路和实验结果。已研制出的这种带通滤波器的主要性能是0.5dB带宽⊿f0.5dB 40MHz±8％,带内波动⊿R≤0.5dB,阻带抑制SS≥40dB。     

交叉耦合盒式结构微带带通滤波器设计

设计了一种交叉耦合盒式结构微带带通滤波器。采用耦合矩阵方法对交叉耦合盒式结构带通滤波器频率响应特性进行了分析,并且在此基础上研制了一种基于E型双模谐振器的非对称响应带通滤波器。滤波器中心频率为6.4 GHz,带宽为0.8 GHz,最小带内插损为1.9 dB,两个传输零点分别位于4.5 GHz 和7.6 GHz,上下阻带抑制度分别大于35dB、47dB。滤波器有效尺寸约为0.34λg *0.43λg。该滤波器具有结构紧凑、带外抑制度高、选择性高的优点。     

一种新型复合结构的四分之一波长带通滤波器

提出了一种基于共面波导(Coplanar Waveguide,CPW)和微带线复合结构的四分之一波长带通滤波器(Bandpass Filter,BPF)。该带通滤波器由两个终端开路的T形微带馈线结构和四个交叉耦合的四分之一波长CPW谐振器组成。通过仿真优化得到其特性曲线图,并分析比较了不同参数对其滤波性能的影响。仿真结果表明,该带通滤波器在其2.97～3.03 GHz的通带内的最小插损低于0.4dB,回波损耗大于30dB,同时其带外衰减都大于25dB。这种滤波器结构紧凑,尺寸小,性能好,可应用于很多微波系统中。     

Integral method of nondestructive testing of optically transparent dielectric elements of band-pass filters

The narrow and wide band-pass filters with high electrical parameters both in the centimeter and millimeter wave band developed in the Microwave laboratory are built on the basis of H- and E-plane inserts made of a high Q dielectric monocrystal leukosapphire (tg δ ? 6*10^?6 in centimeter wave band). The filters based on the E-plane inserts have a rare spectrum of parasitic modes (up to doubled working frequency and higher) and those based on the H-plane inserts have lower insertion loss in the bandwidth. Fig.1 shows the design of a band-pass filter in which the resonators of both the first and second types are used to improve stability of amplitude-frequency characteristic in response to influence of production process and climatic factors. The electrodynamic calculation of such a filter electrical parameters is carried out according to the technique analogous to the one described in [1]. The prooedure of the band-pass filter manufacture envisages the operation of determining whether a specific dielectric element fits for pasting into the filter body. The most expedient testing method for filter elements is the electromagnetic resonance method. However, since the monocrystal leukosapphire is an anisotropic, opticallytransparent material [2], there exists a possibility of using not only the traditional SHF (Super High Frequency) method but also the method of optical testing of the quality of the dielectric element by the shape of conoscopic figures that enables to increase the output of suitable products with reduction of expenditure. A new approach to the nondestructive testing of optically-transparent filter elements using both methods and their mutual dependence in technological process, has been suggested.     

L,S波段高性能窄带有源滤波器的研制

本文研究了一种直接利用晶体管或场效应管来模拟高Ｑ值电感，并利用此电感来制作Ｌ波段和Ｓ波段窄带有源滤波器的方法。利用此方法制作了两个高性能的窄带有源带通滤波器：一个中心频率为２．３ＧＨｚ，其带宽为９０ＭＨｚ左右，带内插入损耗为０ｄＢ；一个中心频率在１．５ＧＨｚ左右，并且中心频率可调，其带宽为８０ＭＨｚ左右，带内有１０ｄＢ的增益     

Side-Wall-Coupled, Strip-Transmission-Line Magnetically Tunable Filters Employing Ferrimagnetic YIG Resonators

This paper describes a new type of band-pass filter configuration for multiple-coupled-resonator magnetically tunable microwave filters. For two or more resonators, this configuration, which employs a coupling slot in the common side wall between two strip-transmission lines, results in the smallest possible air gap and, therefore, the least amount of leakage or fringing flux, and the smallest ampere-turns requirement on the bias magnet. Response curves including pass band insertion-loss, bandwidth, stop-band rejection, spurious response levels and bandwidths, VSWR, and the effect of temperature on these characteristics are presented for a two-resonator band-pass filter of the type employing YIG resonators and making use of a ferrite core electromagnet to obtain the bias field. Performance data are also given for an experimental side-wall-coupled three-resonator filter.     

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。     

C/S波段低损耗LTCC双工器小型化设计

设计了一种基于低温共烧陶瓷(LTCC)工艺的小型化低损耗双工器。该双工器采用经典的LC结构,由S波段低通滤波器(LPF)和C波段带通滤波器(BPF)组成。在两路滤波器分支中加入串联及并联谐振形成传输零点来增加两个通带的抑制。经过电磁仿真优化,实际加工双工器的测试结果与软件仿真结果吻合。其中低通端插损小于0.35 dB,高通端插损小于0.6 dB,且在要求的频段内有着较好的抑制。该小型化双工器已在一些WLAN模块中得到应用。     

一种通带可控的双频SIW滤波器设计

提出了一种通过加载T形槽实现双频可控的基片集成波导带通滤波器。滤波器的双频特性由SIW腔内对称的T形槽线谐振器微扰TE101和TE102模得到。通过改变槽线谐振器的物理尺寸可以实现对滤波器两个通带中心频率的灵活控制。为了验证上述方法的可行性,设计了一个中心频率为3.77 GHz和9.27 GHz的双频滤波器。实测得该双频滤波器两个通带的回波损耗优于11 dB,在3.77 GHz时插入损耗为0.8 dB,第一通带的相对带宽可达13%。仿真和测试结果吻合较好,证实了设计方法的有效性。     

压电换能器电调介质滤波器的设计与实现

为了解决变容管电调窄带滤波器的插入损耗大和承受功率小的问题,研究了用压电换能器作电调元件的电调介质滤波器.分析了压电换能器调谐介质谐振器的机理,讨论了耦合系数和外部Q值的控制方法,仿真结果表明耦合系数和外部Q值随调谐频率的变化较小.采用HFSS软件设计和优化了两级电调介质滤波器的结构,并用高Q值的介质谐振器制作了两级电调介质滤波器.根据ANSYS软件的分析结果,提出了提高电调率的有效措施.当控制电压为0~50V时,滤波器的中心频率调谐范围为4.155~4.205GHz,3dB带宽为37~40MHz.     

Varicap-tuned narrowband filters with extended rejection band based on U-shaped microstrip Resonators

A resonance equation for the first unwanted resonant frequency of tunable microwave U-shaped loop-type resonator with variable capacitance has been derived. This frequency does not depend on the variable capacitance value; it is invariable and proportional to λ-type oscillations. The ascertained feature makes it possible to determine the ratio of the first unwanted resonant frequency to the frequency of the main resonance and control the rejection bandwidth of tunable filters with U-shaped resonators. A narrowband (2%) varicap-tuned filter with extended rejection band has been built and its experimental data are presented. The experimental four-resonator filter could be tuned in the frequency range 225–400 MHz. The filter rejection band in terms of the attenuation level of –40 dB was located in the frequency range 420–1290 MHz, i.e., f _max /f _min = 3.07. Varicap-tuned filters with microstrip U-shaped resonators are shown to have a good potential for their practical use.     

Synthesis of Filter-Limiters Using Ferrimagnetic Resonators

A synthesis procedure is developed for microwave band-pass filters with the Chebyshev response using orthogonal circuit resonators coupled by a ferrimagnetic resonator. A stripline ferrimagnetic resonator filter is analyzed in detail. Equations and graphs are given which allow the selection of ferrimagnetic material and size of the ferrimagnetic sample necessary to achieve a desired bandwidth and insertion loss for a given pass-band response. The theoretical behavior of these circuits as microwave power limiters is discussed and it is shown that the ratio of the limiting threshold to the filter bandwidth is a constant depending only on the pass band response shape. Experimental confirmation of the design information discussed as well as some practical methods of varying the limiting threshold.     

Multiplexer Channel-Separating Units Using Interdigital and Parallel-Coupled Filters

Design theory is presented for strip-line multiplexer channel-separating units which have constant-resistance input impedances so that many units can be cascaded without reflection effects. Each channel unit consists of an interdigital band-pass filter and a band-stop filter which uses parallel-coupled resonators. In order to obtain the desired constant-resistance input impedance, both filters are designed from singly loaded, maximally flat, low-pass prototype filters. A trial design was worked out and constructed so as to have five per cent bandwidth for the separated channel. Excellent agreement between theory and experiment was obtained.