X 波段微带交叉耦合带通滤波器的设计

耦合谐振电路在微波滤波器的设计,尤其是在窄带滤波器的过程中起着非常重要的作用。本文采用 基于耦合系数和外部品质因数的耦合谐振电路滤波器的方法设计了X 波段的开环交叉耦合微带带通滤波器。由于 引入非相邻谐振器之间的交叉耦合,在滤波器的输入端口和输出端口之间有多个通路,这种多径结构能在有限频率 处产生多个传输零点,而且通过调整传输零点的位置,可以调整滤波器选择性和带内群时延性能。设计的滤波器在 介电常数为2. 2、厚度为0. 254mm 的RO5880 介质板上加工,测试结果显示,该滤波器具有结构简单紧凑、损耗低、选 择性高、带外抑制极佳的特点,具有较好的工程应用价值。     

具有缺陷地结构的双频微带天线设计

采用哑铃型缺陷地结构(DGS)设计了一种新型的双频微带天线,天线的主要辐射单元为一对对称的L形贴片,L形贴片所包围的中间区域敷以圆弧形贴片和一个竖向的矩形连接带并将二者融合为一个整体,实现了天线的双频特性。引入哑铃型的DGS结构,并给出了DGS结构的等效电路图,通过改变DGS结构的尺寸改变了等效电路的电感和电容从而改变了天线的频率特性。测试结果表明:天线能够同时工作在低频4.37 GHz和高频6.08 GHz两个频段,满足微波C波段所要求的频率范围。低频和高频的S_(11)分别为-29.76 dB、-11.99 dB,天线实测S_(11)结果和仿真结果基本吻合。     

Planar Ultra-Wideband Bandpass Filter Using Edge Coupled Microstrip Lines and Stepped Impedance Open Stub

The design and implementation of a planar ultra-wideband (UWB) bandpass filter are presented. Three interdigital edge coupled microstrip lines are used for coupling enhancement. A stepped impedance open stub is used for realizing transmission zeros simultaneously in upper and lower stop bands as well as impedance matching in ultra-wide pass band. A pass band from 3.1-10.6 GHz is achieved with an insertion loss of 0.5 dB, a return loss of about 18 dB, a sharp out-of-band-rejection, and a low group delay of only 0.21ns. Single- and double-section filters are realized to meet the UWB mask requirement. The design of the filter is simple, and it shows good frequency response.     

一种平行耦合微带线带通滤波器的设计

运用以综合设计为基础的切比雪夫低通原型电路设计法设计了一种平行耦合微带线带通滤波器。为了验证设计的正确性，利用ADS软件对其原理图进行了仿真和优化，并对由原理图生成的印制板图进行了仿真和改进。     

Ku 波段微带交叉耦合带通滤波器的结构与设计

基于广义切比雪夫滤波器综合理论,本文设计了一个Ku 波段微带发夹谐振型交叉耦合滤波器。该滤波器的拓扑结构为CQ 型。由于引入非相邻谐振器之间的耦合,在有限频率点处产生传输零点,这样不仅使滤波器具有更好的选择性,而且其结构更加紧凑,尺寸也大大缩小。本文通过HFSS 电磁仿真软件对其进行了优化设计。其仿真结果很好地体现了该滤波器的特性。与同阶数的传统滤波器相比,交叉耦合型滤波器具有更好的带外抑制特性,有较好的工程应用意义。     

平行耦合带通滤波器的设计

以一相对带宽为20%的宽带滤波器(中心频率为29.8 GHz,带宽为1 GHz)为例,详细地阐述了设计平行耦合式微带线带通滤波器计算方法,并结合ADS与HFSS的优点,提高仿真的速度与精度.     

平行耦合微带线带通滤波器分析与设计

为了克服平行耦合微带线带通滤波器设计中存在的尺寸大、需要查表、优化困难等问题,提出了一种平行耦合微带线带通滤波器基于ADS软件的设计方法。经过深入的理论分析发现,平行耦合线带通滤波器系统阻抗微带线非谐振单元,长度可尽量取短以减小电路尺寸;利用ADS软件自带滤波器设计工具可得到低通滤波器原型,省去了查表的麻烦;在版图优化上采用调谐方法比优化方法更有效。仿真结果表明,所设计带通滤波器系统阻抗微带线为2.5 mm,中心频率5 GHz,相对带宽10%。该方法在减小滤波器尺寸的同时没有降低滤波器性能,设计实现快速高效。     

基于LTCC的双频段滤波器设计

为了实现高选择性的小型双频段滤波器,该文基于LC等效电路分析法和微波网络分析法,通过建立等效模型、进行等效电路分析及对传输模型的导纳矩阵分析,提出了一种工作在GSM/WLAN的新型低温共烧陶瓷(LTCC)双频滤波器结构。该结构采用介电常数5.9、层厚0.1 mm、型号为Ferro A6的LTCC介质基板加工,在7 mm × 7 mm × 0.5 mm的尺寸下实现了各通带两边都有传输零点的高选择性双频滤波特性。本研究丰富和发展了LTCC双频滤波器的设计方法。     

基于H型缺陷地结构的超宽带带通滤波器设计

微波频段的宽带滤波器一般具有通带插入损耗大,带外抑制性差等问题,为了解决这个问题,采用具有慢波效应的缺陷地结构(DGS)和缺陷微带结构(DMS),设计了一种新型微波频段的超宽带滤波器。分别利用电磁仿真软件HFSS和平面印制板技术对其进行建模仿真和实物加工。实测与仿真结果良好吻合,带内插入损耗优于1.64dB,回波损耗优于13.93dB,通带范围在2.75~8.3GHz,实现相对带宽100.45%,高低阻带均抑制在-10dB以下,且该滤波器结构紧凑,体积小。     

全等宽平行耦合微带线带通滤波器的设计

半波长平行耦合微带线带通滤波器由于其结构紧凑,第二通带的中心频率3倍于主通带中心频率,因而在微波集成电路中获得广泛应用。本文提出一种新的设计方法：耦合线节级联直接设计法。这一方法比传统设计方法简便,适用相对带宽范围较宽,为30～80%,而且可以采用全等宽耦合线,因而滤波器结构简洁。     

Design of Coupled Microstrip Lines (Letters)

An accurate and direct method for designing coupled microstrip lines for any substrate is given once the design curves for any other substrate are known.     

基于隐式空间映射法设计的双频带滤波器

参数提取是隐式空间映射算法(ISM)的关键,为改善参数提取过程中可能导致的算法不收敛性,通过对参数提取过程施加限制条件,对迭代进程加以约束,然后以一种改进的枝节加载双模方形谐振器为例,利用隐式空间映射算法设计了一个可工作在无线局域网(WLAN)频段的微带双频段带通滤波器,中心频率为2.45GHz和5.25GHz,经过3次仿真迭代获得一组合适的设计参量并微调后,得到更优的响应结果,由此验证了算法的可行性和准确性。     

Ultra-Wideband (UWB) Bandpass Filter With Embedded Band Notch Structures

A compact ultra-wideband (UWB) bandpass filter (BPF) with narrow notched (rejection) band in the UWB passband realized on a microstrip line is implemented and presented in this letter for use in wireless communication applications within the unlicensed UWB range set by the Federal Communications Commission (FCC). The filter consists of five short-circuited stubs separated by nonredundant connecting lines in order to exhibit a high selectivity filtering characteristic. The narrow notched (rejection) band was introduced by using a new technique which involves embedding open stubs in the first and last connecting lines in order to reject any undesired existing radio signal which may interfere with the determined UWB passband. The bandwidth of the notched filter can be controlled by adjusting the width of the stubs or the gaps or both. The length of the stubs can be tuned to select a specific frequency for the notched band. The embedded stubs can be used to excite single or double band-reject response. Two UWB BPFs with narrow notched band having a fractional bandwidth (FBW) of about 4.6% and 6.5% were realized theoretically and verified by full-wave EM simulation and the experiment. Excellent agreement between the predicted and measured results was obtained and is demonstrated     

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。     

Dimensions of Microstrip Coupled Lines and Interdigital Structures (Short Papers)

A method is presented for finding dimensions of coupled lines and interdigital structures on microstrip given the electrical properties. Both a graphical approach and computer approach using polynomial approximations are given. These results are within 1 percent of Bryant and Weiss' dimensions for coupled lines for most practical stripwidths and spacings. Experimental data for a 10-percent bandwidth microstrip interdigital filter are given.     

非等长微带SIR平行耦合带通滤波器的设计

本文提出应用非等长微带SIR（阶梯阻抗谐振器）构成平行耦合带通滤波电路的设计方法。它保持等长SIR滤波电路能够有效抑制高次谐波的特点，又增加了设计的灵活性。本文同时给出应用级联矩阵计算这种滤波电路工作衰减的公式．可以方便地分析宽范围的频率响应。     

A Compact Wideband Bandpass Filter Using Transversal Resonator and Asymmetrical Interdigital Coupled Lines

A compact wideband microstrip bandpass filter using transversal resonator and asymmetrical interdigital coupled lines is proposed in this letter. A wide passband is first constructed using transversal signal-interference technique, resulting a pair of transmission zeros at each side of the desired passband. By driving this transversal resonator with two asymmetrical interdigital coupled lines at two sides, five extra transmission zeros are generated in the lower/upper stopbands with excellent dc-choked property, thus making up a wide passband with improved out-of-band performance. This wideband microstrip filter is then designed, implemented and experimented. Good insertion/return losses, flat group delay and good out-of-band rejections are achieved as demonstrated in both simulation and experiment.     

微带抽头线发夹型带通滤波器的设计及优化

介绍一种用ADS( Advanced Design System)软件进行设计和优化微带抽头线发夹型带通滤波器.详细地给出了设计步骤及其各个参数的确定.以一个中心频率为4.8 GHz,带宽为200 MHz的微带带通滤波器的设计及优化为例,给出了仿真结果,并进一步给出了Momentum仿真结果.     

Design of Coupled Microstrip Lines by Optimization Methods (Short Paper)

The design of two coupled microstrip lines is converted into an optimization problem, which is then solved by two methods of nonlinear mathematical programming. New formulas for calculating the first approximation of the solution, i.e., the starting point of the optimization, are given.