新型微扰结构双模贴片带通滤波器设计

针对微带滤波器高性能小型化的需求,提出了一种方环形微扰单元的双模贴片带通滤波器的设计.该滤波器由方形贴片作为谐振器,输入、输出端口采用直接馈电,具有对称结构.利用在方形贴片上蚀刻出方环形缺口的方式,对方形贴片谐振器进行微扰,实现双模滤波器.通过电磁仿真软件Ansoft HFSS分析了微扰单元的特性,对双模滤波器的性能进...     

新型紧凑型带通滤波器的设计

文章设计了两个通带位于超宽带低频范围的带通滤波器,用一种T型结构来代替传统带通滤波器中的四分之一波长传输线,这种替代减小了滤波器的尺寸.而且,可以很方便的控制位于滤波器通带两端的传输零点,即合理的调节开路支线的电长度,进而可以方便的控制滤波器的通带范围.为了证明以上新型滤波器的优点,设计了两个开路支线电长度不同的带通滤...     

基于HFSS的微调谐腔体带通滤波器设计

针对微调谐腔体带通滤波器设计制造中存在的问题,介绍了腔体带通滤波器的总体设计;论述了需要解决的问题,如优化计算、提高仿真精度和简化调谐结构,并对二端口网络等效替换、整体仿真和微调谐关键技术进行了分析;最后阐述了仿真与性能测试结果分析,测试结果分析说明微调谐腔体带通滤波器设计精确且拥有很好的应用前景。     

小型化微波悬置屏蔽微带线滤波器的设计

本文给出了悬置屏蔽微带线交指滤波器的设计公式，并成功的研制了Ｘ线段小型化悬置屏蔽微带线交指滤波器，实验结果和理论计算吻合得很好。     

MNG传输线带通滤波器设计

为了以更简单的结构、更少的电路元件实现更好的左手媒质特性,设计了一种新型磁负介质传输线（MNG）。该传输线具有负的磁导率和正的介电常数,是对传统混合左右手（CRLH）传输线理论上的扩展和设计上的改进。采用该MNG传输线设计了一个切比雪夫带通滤渡器,获得任意可调的双频带特性,其仿真和测量结果吻合很好,验证了MNG传输线的设计理论。该MNG传输线所具有的非线性相位响应特性,可以实现耦合器、滤波器、双模天线等多种新颖的可调双频带微波器件的设计。     

幅频算术对称无源带通滤波器的优化设计

为解决无源带通滤波器幅频算术对称问题,提出一种基于极点放置技术的优化设计方法,即在网络综合法设计的滤波器电路基础上,将并臂电感换成串臂电感,在此电感上并联电容增加衰减极点,并利用电路优化技术,使得幅频特性算术对称.实例结果表明,该方法能够使滤波器幅频特性算术对称,而且带内波动小,电路结构简单,阶数少,插入损耗低.     

非谐振型结构的复合左右手带通滤波器小型化设计

提出了一种非谐振型结构的复合左右手带通滤波器，可应用于WLAN频段，该结构只采用一个复合左右手传输线单元，单元内部的交指结构提供等效左手电容，过孔结构提供等效左手电感，单元内部存在交叉耦合，通过调整交叉耦合电容和左右手参数，可产生2个可控传输零点并缩减尺寸，通过添加DGS缺陷地结构，能进一步优化滤波器性能，经过仿真优化最终设计出一款具有较高选择性、较好带外抑制性能的带通滤波器。实测结果显示:滤波器工作频率为5.98ＧＨｚ，3ｄＢ带宽为940 ＭＨｚ，带内插损最大值为1.59ｄＢ，相比传统滤波器设计，该结构大幅度减小了器件体积。     

慢波结构SIR双频带通滤波器设计

本文通过分析阶梯阻抗谐振器（SIR）和慢波结构谐振器的特性,提出了利用SIR谐振器的寄生通带产生第二通带的双频带通滤波器设计方法,以达到滤波器小型化的目的;并基于0°馈电结构获取传输零点的原理对滤波器阻带性能进行优化。最后结合ADS仿真软件设计了一个中心频率在2.4GHz和5.2GHz的微带双频带通滤波器。仿真结果表明滤波器具有良好的带内带外特性。本文所设计的滤波器尺寸小,性能好,具有很好的实用价值。     

Continuous-time analog filter with passband constant IIP3 based on common-gate amplifier

This paper presents an analog filter based on Rauch biquadratic cell. The filter exploits an improved analog stage that makes linearity performance uniform over the entire pass-band frequency region. All feedback analog filters suffer from poor linearity when the input tones frequency is in close proximity to the closed-loop poles frequency, where loop-gain reduces. This often forces an overdesign with higher current (higher power consumption) and/or higher overdrive voltages (lower dynamic range) in order to meet the linearity specifications over the whole filter pass-band region. The hereby proposed Rauch scheme resolves such a binding issue without power increasing and having the same IIP3 at low and at high frequency (up to the filter closed-loop poles frequency). Hence the linearity performance is in first approximation independent on the input tones bandwidth. In order to validate the hereby proposed idea a 4th-order 25 MHz ?3 dB bandwidth pseudo-differential filter has been designed and simulated in CMOS 28 nm technology. The prototype consumes 820 µW from 1 V supply voltage and has 15  and 13 dBm IIP3 at 5 and 6 and 20 and 21 MHz input tones, respectively.     

On a development possibility of a tunable microwave passband filter based on dielectric resonator with high TC film

Measurements of temperature dependence of "YBa₂Cu₃O_7-x thin film on SrTiO₃ substrate" structure effective impedance have been performed in 8-mm wave band by means of quasioptical dielectric resonator with whyspering gallery modes. This dependence appeared to be a series of quasiperiodical oscillation peaks of high steepness. Experiments on investigation of external electric field impact on parameters of the resonator loaded by the structure were carried out. It was found that electric field up to 3 kV/cm leads to a shift of the effective impedance temperature dependence to lower temperature and doesn't impact on the form of the dependence. Herewith the field of 2.5 kV/cm causes a shift of the resonator frequency by 108 MHz with negligible reduction of the loaded quality factor Q_L (less than in 1.5 times). Operating frequency was 35 GHz and loaded quality was about 10³. A proposal about possibility of tunable passband filter design and ways of retuning bandwidth enhancment are discussed.     

Characteristic impedance of microshield lines with arbitrary shieldcross section

A generalized potential-matching method incorporating reflection matrices is developed to calculate the capacitance of microshield lines with trapezoidal, circular, and V-shaped shields. Both completely shielded and half-shielded lines are analyzed. The effects of membrane thickness, strip width, and gapwidth on the characteristic impedance are studied     

High-frequency-operated converters based on transmission lines

A new approach to converter realization is presented. The realization is based on a topology that incorporates transmission lines as its main component. The method may have applications in systems consisting of existing transmission lines, for high frequencies, high energy pulses, spikes, and transients. Important advantages of this realization are robust construction and constant conversion ratio, as well as characteristics of resistive load at the input, which enables operation at high frequency. Using this method, pulses of 100 V amplitude and 100 ns width were converted, which is similar to operating a converter at 10 MHz     

基于FPGA的程控滤波器的设计

以单片机和可编程逻辑器件(FPCA)为控制核心,设计了一个程控滤波器,实现了小信号程控放大、程控调整滤波器截止频率和幅频特性测试的功能.其中放大模块由可变增益放大器AD603实现,最大增益60dB,10 dB步进可调,增益误差小于1%.程控滤波模块由MAX297低通滤波、TLC1068高通滤波及椭圆低通滤波器构成,滤波模式用模拟开关选择.本系统程控调整有源滤波的-3 dB截止频率,使其在1～30 kHz范围内可调,误差小于1.5%.此外,采用有效值采样芯片AD637及12位并行A/D转换器MAX120实现了对扫频信号幅度的测量.     

Tunable bandpass filter based on capacitor-loaded metamaterial lines

A bandpass filter is constructed by loading a left-handed metamaterial transmission line with an additional shunt capacitor. The shunt capacitor provides more freedom to control the passband characteristics of the resulting metamaterial line. A bandpass filter is designed with a centre frequency that is tunable from 0.45 to 0.65 GHz.     

复合左右手传输线的小型超宽带滤波器设计

基于复合左右手传输线的原理,设计了一款新型超宽带滤波器,结构简单且尺寸只有0.5 cm×1.5 cm,左手电容是由微带线结构耦合形成,左手电感由接地短截线形成.通过仿真结果与实物测试可知超宽带滤波器的带宽为3.3～10.2 GHz,插入损耗小于1dB,回波损耗小于-12.5 dB.该滤波器可用于超宽带无线通信系统中.     

变形矩形和V形微屏蔽线传输特性的矢量有限元计算

微屏蔽线在使用过程中难免会产生变形。本文利用矢量有限元法讨论了矩形微屏蔽线和V形微屏蔽线的变形对其传输特性的影响,其中传输特性包括主模截止波长、单模带宽和主模电场结构。计算结果显示,两种微屏蔽线的变形对三种传输特性均有较大影响,这些数值计算结果对两种微屏蔽线在使用过程中出现变形时对整体器件的影响有较强的指导意义。     

基于多层左手传输线的小型滤波器仿真设计

基于Yasushi Horii等人提出的多层左右手复合传输线理论,对原有结构与特性做了进一步的研究和分析,提出了改进措施,大幅度提高了原有中心频率,消除了高频时前端谐振现象,显著改善了带内特性.通过数值仿真,总结出各结构参数变化对中心频率及带内特性的影响,并在此基础上设计出一X波段,平面尺寸为5.1 mm×3.8 mm的高性能带通滤波器,其中心频率为9.5G,1 G带宽,带内损耗小于0.7 dB,8 G时S21衰减至-30 dB.