一种新型结构的宽带宽磁调谐带通滤波器设计

本文主要介绍了一种工作于2～6GHz,3dB带宽大于200MHz的磁调谐带通滤波器的设计原理及方法,这种宽带宽的磁调谐带通滤波器利用多晶铁氧体材料制作,采用了新的耦合结构,为实现宽频带调谐,采用了与传统YIG滤波器磁路结构不同,具有不同磁场梯度的新型磁路结构设计.并通过实验验证了设计的正确性,实验结果表明该种结构设计的磁调谐带通滤波器,不仅工作频段宽,与一般的YIG带通滤波器相比具有3dB带宽,调谐方便的优点,拓展了磁调谐带通滤波器的应用.     

0.8～18GHz宽频YIG带通滤波器设计与仿真

针对现代电子系统对YIG带通滤波器超宽工作频段的要求,本文给出了一种0.8~18GHz宽频YIG带通滤波器的设计。通过磁路结构、谐振耦合结构的设计、仿真和优化,采用自屏蔽磁路、宽频谐振耦合技术,研制的宽频YIG带通滤波器主要技术指标为:工作频率范围0.8~18GHz;插入损耗≤11.5dB;-3dB带宽≥13MHz;线性:±12MHz;磁滞:≤15MHz;失谐隔离≥65dB;工作温度范围-40^+60℃;外形尺寸35.5mm×35.5mm×35.5mm。     

新型BST薄膜可调带阻滤波器

提出了一种基于共面传输线结构的新型带阻滤波器,利用该结构在沉积有钛酸锶钡(BST—0.5)薄膜的氧化镁基片上设计并制作了一个可调带阻滤波器。测试结果表明,在30V的外加偏压下,带阻滤波器的传输特性曲线向高频方向整体移动了190MHz,其形状基本保持不变。     

SIR带状线带阻滤波器的设计

将具有阻带特性的微带马刺线结构引入到带状线中,设计了一款中心频率为2.32 GHz,相对带宽为9.5%,阻带衰减为50 dB的三阶马刺线式带阻滤波器。相比于传统的并联开路短截线型带阻滤波器,马刺线式带阻滤波器的横向尺寸大为减小,结构更加紧凑。采用SIR(stepped-impedance resonator)结构,按相同指标设计了一款三阶SIR马刺线式带阻滤波器。与马刺线式带阻滤波器相比,SIR马刺线式带阻滤波器结构更为紧凑,纵向尺寸缩小约17%,并具有更好的谐波抑制特性。     

半圆形谐振器双频带带阻滤波器的研制

为了抑制干扰信号,基于半圆形谐振器设计了双频带带阻滤波器。该滤波器由两个半圆形谐振器和部分耦合微带线组成。基于HFSS对双频带带阻滤波器进行仿真,同时制作并且测试了双频带带阻滤波器。仿真结果和测试结果基本上一致。测试结果显示,该双频带带阻滤波器在阻带外存在三个反射零点,改进了滤波器的选择特性。滤波器具有体积小、选择性高、结构简单等优点。     

一种新型CPW滤波器的设计

设计了一种新型结构的CPWDGS单元,这种DGS结构在CPW两侧的接地面上对称刻蚀一定形状,形成带阻特性。通过对DGS结构单元的适当组合可以实现宽阻带的微波滤波器,仿真结果表明,该结构具有陡峭的阻带衰减特性,通过改变DGS单元的尺寸可以工作于不同的频段,增加单元数目可以改善带阻滤波器的性能。设计制作了一个五单元的CPW带阻滤波器,测试结果与仿真结果相吻合。这种结构的带阻滤波器设计灵活,结构简单、易于制作、便于安装,具有广泛的应用前景。     

新型缺陷地结构带阻滤波器

提出一种W型缺陷地结构(WDGS)单元,该WDGS单元性能优越,结构简单,便于加工。将该单元结构应用于带阻滤波器设计中,有效地提高了滤波器的阻带特性并减小了滤波器的尺寸。详细分析了WDGS单元几何参数对频率和带宽的影响。将三个相同WDGS级联,有效地增大了带阻滤波器的带宽并提高了其对信号的抑制效果。结果表明:该带阻滤波器在2.6~3.4 GHz,对信号的抑制从–25 dB到–37 dB。     

一种新型缺陷地结构带阻滤波器

提出了一种新型缺陷地结构的带阻滤波器.该单元在现有各种形状的基础上,采用新的缺陷地结构,实现了带阻特性.该单元结构简单,易于加工,性能优越,可进一步减小滤波器尺寸.文中对新型缺陷地结构单元的带阻特性进行了分析,并建立仿真模型,从理论和实验中得到最佳的性能.实现了有较宽阻带的周期性缺陷单元.能够有较宽的阻带.最终设计出实际带阻滤波器,并对产品进行了实际测量,得出与仿真相似的结果.     

高选择性吸收式可调带阻滤波器的研究

该研究利用耦合相消原理设计了一种吸收式可调带阻滤波器.在传统耦合相消结构的基础上,提出了一种新的结构,通过增加耦合结构的阶数以及增大耦合支路中谐振器的电长度,使得滤波器阻带特性的Q值增大,从而提高了滤波器的选择性.通过调节加载在谐振器上变容二极管的偏置电压,实现滤波器带阻中心频率可调.并对实测结果和仿真结果进行了探讨.     

一种窄带SIR带阻滤波器的设计

介绍了嵌入式并联λ8/4(λ8为波长)的开路支节的基本结构与特性.采用带状线,设计了一款中心频率为2.46 GHz、阻带宽度50 MHz、最大阻带衰减为60 dB的三阶嵌入式并联开路支节窄带带阻滤波器.与传统的并联开路支节带阻滤波器相比,嵌入式并联开路支节带阻滤波器的横向尺寸减小,结构紧凑.采用阶梯阻抗谐振器(SIR)结构,按相同指标设计了一款三阶嵌入式SIR窄带带阻滤波器.与嵌入式并联开路支节带阻滤波器相比,嵌入式SIR带阻滤波器结构更为紧凑,纵向尺寸缩小约17.5％,并具有更好的谐波抑制特性.     

新型高Q值U形缺陷地结构带阻滤波器

提出了一种新型的U形缺陷地结构(DGS)单元,该单元可以用来设计高Q值带阻滤波器。减小U形DGS结构两臂的槽宽及槽之间的距离,或在U形槽内加上贴片,可以增大Q值。最后用三个级联的U型DGS结构设计了一个高Q值的带阻滤波器,实验结果表明所设计的滤波器的Q值为35.3。     

窄带带阻滤波器的仿真设计

主要介绍了一种窄带带阻滤波器的设计方法及过程,用此方法设计了一个7GHz的带阻滤波器,并使用ADS软件对此滤波器进行仿真优化。     

Band-Stop Filters For High-Power Applications

There are several advantages to the use of band-stop filters, rather than band-pass filters, in many systems. This is shown to be particularly true when signals at high-power levels must be transmitted or rejected. A formula has been derived which expresses the external Q of each resonator in a band-stop filter in terms of the element values of the normalized low-pass prototype and the parameters of the frequency transformation. The peak power capacity of iris-coupled waveguide cavity filters and TEM filters using capacitively coupled inductive stubs is then determined in terms of the external Q of the first resonator and the dimensions of the resonator. Experimental results given for a waveguide band-stop filter show good agreement with theory.     

A Novel Low-Pass Filter With an Embedded Band-Stop Structure for Improved Stop-Band Characteristics

This letter presents a novel design of a microstrip low- pass filter (LPF) with an embedded band-stop structure, which is constructed from a simple two transmission line band-stop filter. The band-stop structure is ingeniously embedded into a classical step-impedance microstrip LPF. The stop-band of the proposed LPF is more than two times broader than the original design, while its cut-off frequency remains at 1.8 GHz. The embedded structure does not increase the physical dimension of the LPF, but improves the performance significantly. Measured results agree with simuAcircnot lation well, and validate the dual-frequency design method.     

一款大功率带阻滤波器的设计仿真与实现

为了准确测试杂散小信号,在射频输入信号进入频谱仪之前采用带阻滤波器滤除基波大信号,保证进入频谱仪混频器端口的功率电平符合要求。设计了一款可过大功率的短波带阻滤波器,该滤波器不但可有效滤除基波大信号,避免频谱仪的饱和非线性失真,且带外平坦,对需要测量的杂散信号几乎无损耗。仿真结果证明了该设计方案的可行性。     

Electromagnetic crystal (EMXT) waveguide band-stop filter

An electromagnetic crystal (EMXT) with a bandgap around 35 GHz is used as the top and/or bottom walls of a rectangular waveguide. Because of its bandgap, such an EMXT waveguide is a very effective band-stop filter with the rejection band centered at 35 GHz. More than 70 dB of isolation for the rejection band and less than 2 dB of insertion loss for the pass band are measured. Finite element simulation of the EMXT band-stop filter agrees very well with measurements. Using tunable EMXT walls, a band-stop filter with adjustable center frequency and bandwidth can also be realized.     

A Ferrimagnetically-Tuned Parametric Amplifier

A parametric amplifier can normally be tuned only over relatively restricted frequency ranges. One of the basic reasons for this tuning difficulty is that more than one frequency range is of importance for, in addition to the signal frequency, a pump frequency and one or more sum or difference frequencies must be considered. In this paper a tunable negative-resistance parametric amplifier is described which uses ferrimagnetically-tuned signal and idler circuits, together with a fixed-frequency pump source. This amplifier is unique in two respects. One is that the amplifier is electrically tuned through the use of yttrium iron garnet (YIG) resonators. Secondly, useful low-noise performance has been achieved over a tuning range of almost one octave, this amplifier thus successfully demonstrates that the technique of magnetic tuning with YIG resonators can be applied to a device as complex as a parametric amplifier in much the same manner as it has been applied in the past to microwave band-pass and band-stop filters.     

宽带压控带阻滤波器分析

在继电保护通讯中,通讯信号在传输过程中通常会受到外部某一宽频段信号的干扰。特别是在载波通讯方面,其严重影响了通讯质量以及继电保护装置动作。但传统的窄带阻滤波器的衰减范围过小,无法达到衰减此宽频段干扰信号的理想效果。而一种宽带压控型带阻滤波器能够满足这一要求,同时具有电路性能稳定、增益便于调节的优点。因此,分析这种压控型宽带阻滤波器,研究其输入与输出电压波形、幅频特性和相频特性,并扩展实例应用,证明其具有一定的现实意义。     

Design of Band-Stop Filters in the Presence of Dissipation

The insertion loss vs. frequency characteristic of equal-element band-stop filters is derived for large as well as small degrees of dissipation, and for any number of resonators. These results are presented as curves for one through eight resonator filters. The equal-element band-stop filter, for small dissipation, is shown to have the lowest pass-band loss for a specified stop-band characteristic of all possible filters that can be represented by a low-pass prototype. Design procedures and examples are explained for waveguide and TEM band-stop filters. This includes selecting the optimum number of resonators, the resonator lengths, and the coupling reactance. Experimental results on C-band waveguide and UHF coaxial filters are presented; the results are in good agreement with the theory. This approach makes possible complete prediction of the filter response and results in lower pass-band loss than could be obtained with previously used approaches.