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Electrically triggered dual-band tunable terahertz metamaterial band-pass filter based on Si_3N_4–VO_2–Si_3N_4 sandwich 被引量:3
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作者 Shuai Zhao Fangrong Hu +4 位作者 Xinlong Xu Mingzhu Jiang Wentao Zhang Shan Yin Wenying Jiang 《Chinese Physics B》 SCIE EI CAS CSCD 2019年第5期111-116,共6页
We experimentally demonstrate an electrically triggered terahertz(THz) dual-band tunable band-pass filter based on Si_3 N_4–VO_2–Si_3 N_4 sandwich-structured hybrid metamaterials. The insulator–metal phase transiti... We experimentally demonstrate an electrically triggered terahertz(THz) dual-band tunable band-pass filter based on Si_3 N_4–VO_2–Si_3 N_4 sandwich-structured hybrid metamaterials. The insulator–metal phase transition of VO_2 film is induced by the Joule thermal effect of the top metal layer. The finite-integration-time-domain(FITD) method and finite element method(FEM) are used for numerical simulations. The sample is fabricated using a surface micromachining process,and characterized by a THz time-domain-spectrometer(TDS). When the bias current is 0.225 A, the intensity modulation depths at two central frequencies of 0.56 THz and 0.91 THz are about 81.7% and 81.3%, respectively. This novel design can achieve dynamically electric–thermo–optic modulation in the THz region, and has potential applications in the fields of THz communications, imaging, sensing, and astronomy exploration. 展开更多
关键词 tunable band-pass filter hybrid metamaterials TERAHERTZ VANADIUM dioxide (VO2)
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Solar-blind ultraviolet band-pass filter based on metal–dielectric multilayer structures 被引量:1
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作者 王天娇 徐尉宗 +4 位作者 陆海 任芳芳 陈敦军 张荣 郑有炓 《Chinese Physics B》 SCIE EI CAS CSCD 2014年第7期404-408,共5页
Solar-blind ultraviolet (UV) band-pass filter has significant value in many scientific, commercial, and military appli- cations, in which the detection of weak UV signal against a strong background of solar radiatio... Solar-blind ultraviolet (UV) band-pass filter has significant value in many scientific, commercial, and military appli- cations, in which the detection of weak UV signal against a strong background of solar radiation is required. In this work, a solar-blind filter is designed based on the concept of "transparent metal". The filter consisting of Al/SiO2 multilayers could exhibit a high transmission in the solar-blind wavelength region and a wide stopband extending from near-ultraviolet to infrared wavelength range. The central wavelength, bandwidth, Q factor, and rejection ratio of the passband are numerically studied as a function of individual layer thickness and multilayer period. 展开更多
关键词 solar-blind band-pass filter metal-dielectric multilayer
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0.22 THz Waveguide Bandpass Filter with High Stop-Band Suppression 被引量:1
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作者 Meng-Juan Zhao Yong Zhang Shuang Liu 《Journal of Electronic Science and Technology》 CAS CSCD 2017年第3期263-266,共4页
A terahertz(THz) waveguide band-pass filter using an iris inductive window coupled structure was designed and fabricated.The filter was designed at0.22 THz with a pass band of 20 GHz.The measured results show that t... A terahertz(THz) waveguide band-pass filter using an iris inductive window coupled structure was designed and fabricated.The filter was designed at0.22 THz with a pass band of 20 GHz.The measured results show that the center frequency is 0.218 THz with a pass band of 0.205 THz to 0.231 THz,the minimum insertion loss is 1.26 d B at 0.224 THz,and the return loss is less than 13.1 d B.The stop-band suppression is65.6 d B at 0.193 THz and 51.8 d B at 0.243 THz,respectively,which means a good performance of high stop-band suppression.A good agreement exists between the measured S-parameters and the simulated ones,especially in the upper band.The proposed THz waveguide filter has potential applications in THz communications. 展开更多
关键词 Index Terms--High stop-band suppression terahertz waveguide band-pass filter
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A tunable passive mixer for SAW-less front-end with reconfigurable voltage conversion gain and intermediate frequency bandwidth 被引量:1
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作者 陶健 fan xiangning zhao yuan 《High Technology Letters》 EI CAS 2018年第1期10-18,共9页
An adjustable mixer for surface acoustic wave( SAW)-less radio frequency( RF) front-end is presented in this paper. Through changing the bias voltage,the presented mixer with reconfigurable voltage conversion gain( VC... An adjustable mixer for surface acoustic wave( SAW)-less radio frequency( RF) front-end is presented in this paper. Through changing the bias voltage,the presented mixer with reconfigurable voltage conversion gain( VCG) is suitable for multi-mode multi-standard( MMMS) applications. An equivalent local oscillator( LO) frequency-tunable high-Q band-pass filter( BPF) at low noise amplifier( LNA) output is used to reject the out-of-band interference signals. Base-band( BB) capacitor of the mixer is variable to obtain 15 kinds of intermediate frequency( IF) bandwidth( BW). The proposed passive mixer with LNA is implemented in TSMC 0. 18μm RF CMOS process and operates from 0. 5 to 2. 5 GHz with measured maximum out-of-band rejection larger than 40 d B. The measured VCG of the front-end can be changed from 5 to 17 d B; the maximum input intercept point( IIP3) is0 d Bm and the minimum noise figure( NF) is 3. 7 d B. The chip occupies an area of 0. 44 mm^2 including pads. 展开更多
关键词 RECONFIGURABLE radio frequency (RF) FRONT-END multi-mode multi-standard( MMMS) high-Q band-pass filter ( BPF) cross-coupled common gate low noise amplifier ( CC-CGLNA) CMOS
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PHASE CORRECTION AND BAND-PASS FILTERS IN CT IMAGING
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作者 赵生妹 蒋大真 《Nuclear Science and Techniques》 SCIE CAS CSCD 1993年第2期101-107,共7页
This paper reports the use of the fast Fourier transform (FFT) in the direct Fourier transform method (DFM) in Computerized Tomography (CT) reconstruction. Phase corrections are needed in the CT reconstruction. In ord... This paper reports the use of the fast Fourier transform (FFT) in the direct Fourier transform method (DFM) in Computerized Tomography (CT) reconstruction. Phase corrections are needed in the CT reconstruction. In order to eliminate the image distortion from the basic DFM, Padding and band-pass filters are used in the improved DFM. Finally, some reconstructions from simulated projections and several experimental results are given. 展开更多
关键词 CT imaging Phase CORRECTION band-pass FILTERS FOURIER TRANSFORMATION PADDING
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Tunable graphene-based mid-infrared band-pass planar filter and its application
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作者 Somayyeh Asgari Hossein Rajabloo +1 位作者 Nosrat Granpayeh Homayoon Oraizi 《Chinese Physics B》 SCIE EI CAS CSCD 2018年第8期290-296,共7页
We have designed and proposed the edge modes supported by graphene ribbons and the planar band-pass filter consist- ing of graphene ribbons coupled to a graphene ring resonator by using the finite-difference time-doma... We have designed and proposed the edge modes supported by graphene ribbons and the planar band-pass filter consist- ing of graphene ribbons coupled to a graphene ring resonator by using the finite-difference time-domain numerical method. Simulation results show that the edge modes improve the electromagnetic coupling between devices. This structure works as a novel, tunable mid-infrared band-pass filter. Our studies will benefit the fabrication of planar, ultra-compact nano-scale devices in the mid-infrared region. A power splitter consisting of two output ribbons that is useful in photonic integrated devices and circuits is also designed and simulated. These devices are useful for designing ultra-compact planar devices in photonic integrated circuits. 展开更多
关键词 band-pass filter GRAPHENE surface plasmons power splitter
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DUAL MODE WIDEBAND BAND-PASS FILTER WITH NOTCHED BAND FOR COMMUNICATION SYSTEM
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作者 Wang Hui Yang Guo Wu Wen Ge Sheng 《Journal of Electronics(China)》 2011年第4期444-449,共6页
This paper presents a planar microstrip wideband dual mode Band-Pass Filter(BPF) from 2 GHz to 3.4 GHz with a notched band at 2.62 GHz.The dual mode band-pass filter consists of a ring resonator with two quarter-wavel... This paper presents a planar microstrip wideband dual mode Band-Pass Filter(BPF) from 2 GHz to 3.4 GHz with a notched band at 2.62 GHz.The dual mode band-pass filter consists of a ring resonator with two quarter-wavelength open-circuited stubs at =90o and =0o,respectively.A square perturbation stub has been put at the corner of the ring resonator to increase the narrow stopbands and improve the performance of selectivity.By using a parallel-coupled feed line,a narrow notched band is introduced at the required frequency and its Fractional BandWidth(FBW) is about 5%.The proposed filter has a narrow notched band and a wide pass-band with a sharp cutoff frequency characteristic,the attenuation rate for the sharp cutoff frequency responses is 297.17 dB/GHz(cal-culated from 1.959 GHz with-34.43 dB to 2.065 GHz with-2.93 dB) and 228.10 dB/GHz(calculated from 3.395 GHz with-2.873 dB to 3.507 GHz with-28.42 dB).This filter has the advantages of good insertion loss in both operating bands and two rejections of greater than 16 dB in the range of 1.59 GHz to 1.99 GHz and 3.49 GHz to 3.98 GHz.Having been presented in this article,the measurement results agree well with the simulation results,which validates our idea. 展开更多
关键词 Communication system band-pass Filter(BPF) Dual mode Notched band
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A tunable dual-narrowband band-pass filter using plasma quantum well structure
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作者 戴燚 刘少斌 +2 位作者 王身云 孔祥鲲 陈忱 《Chinese Physics B》 SCIE EI CAS CSCD 2014年第6期370-374,共5页
A tunable dual-narrowband pass-band filter is designed. A one-dimensional photonic crystal (1D PC) is comprised of alternate dielectric layer and vacuum layer. Two quantum wells (QWs) as defects can be constructed... A tunable dual-narrowband pass-band filter is designed. A one-dimensional photonic crystal (1D PC) is comprised of alternate dielectric layer and vacuum layer. Two quantum wells (QWs) as defects can be constructed by sandwiching two plasma slabs symmetrically in the 1D PC, and a dual-narrowband pass-band filter is formed. The conventional finite- difference time-domain (FDTD) method and piecewise linear current density recursive convolution (PLCDRC)-FDTD method are applied to the dielectric and plasma, respectively. The simulation results illustrate that the dual-narrowband frequencies can be tuned by changing the plasma frequency. The pass band interval and the half-power bandwidths (-3-dB band widths) are related to the space interval between two QWs. 展开更多
关键词 quantum well dual-narrowband pass-band filter PLASMA
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Controls of pass-bands in asymmetric acoustic transmission
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作者 孙宏祥 张淑仪 袁寿其 《Chinese Physics B》 SCIE EI CAS CSCD 2016年第12期92-97,共6页
The controls of the pass-bands in an asymmetric acoustic transmission system are investigated numerically and ex- perimentally, and the system consists of a periodical rectangular grating and two uniform brass plates ... The controls of the pass-bands in an asymmetric acoustic transmission system are investigated numerically and ex- perimentally, and the system consists of a periodical rectangular grating and two uniform brass plates in water. We reveal that the pass-band of the asymmetric acoustic transmission is closely related to the grating period, but is affected slightly by the brass plate thickness. Moreover, the transmittance can be improved by adjusting the grating period and other structural parameters simultaneously. The control method of the system has the advantages of wider frequency range and simple operation, which has great potential applications in ultrasonic devices. 展开更多
关键词 asymmetric acoustic transmission pass-band control grating diffraction Lamb mode
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Electromagnetic Band Gap Loaded Square Waveguide Band-Pass Filter for Dual-Polarized Application
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作者 Yi-Ming Tang 《Wireless Engineering and Technology》 2012年第4期210-213,共4页
An Electromagnetic Band Gap (EBG) loaded square waveguide Band-Pass Filter (BPF) is proposed in this paper. It’s simply composed by symmetrically loading periodical metal diaphragms on each wall of a square waveguide... An Electromagnetic Band Gap (EBG) loaded square waveguide Band-Pass Filter (BPF) is proposed in this paper. It’s simply composed by symmetrically loading periodical metal diaphragms on each wall of a square waveguide. The influences of insert sizes and loading periods on the overall BPF performances are analyzed. Experimental results agree well with those predicted. 6 GHz pass-band with insert loss less than 1 dB, 2.5 GHz stop-band and larger than 25 dB polarization isolation can be obtained. The BPF can be applied in dual-polarized waveguide-based antenna-feed systems. 展开更多
关键词 Electromagnetic band Gap (EBG) band-pass Filter (BPF) Dual-Polarized SQUARE Waveguide
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Universal Band Pass Sampling Algorithm for Integration of Multiple Wireless Technologies Using Software Defined Radio Platform
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作者 Sriramachandra Murthy Budaraju Bhagyaveni Marcharla Anjaneyulu 《Circuits and Systems》 2016年第4期497-505,共9页
Software Defined Radio (SDR) architecture allows us to integrate different mobile technologies using common hardware but with different software modules. To achieve this, we need to keep the signal in digital form for... Software Defined Radio (SDR) architecture allows us to integrate different mobile technologies using common hardware but with different software modules. To achieve this, we need to keep the signal in digital form for as much portion of the circuitry as possible, so that the implementation could be carried out by programmable digital processors. For this purpose, the incoming radio frequency (RF) signal is down converted to baseband spectrum using band pass sampling method. Research works carried out so far in this field have developed a few algorithms for band pass sampling. But, these algorithms are not much useful for most of the mobile communication systems and they use complex methodology for computing the sampling frequency values. In order to use the SDR platform to integrate all current wireless technologies, an efficient, cost effective and less complex algorithm that can be labelled as universal band pass sampling algorithm is developed in this paper for multiple mobile systems. This algorithm is based on a novel idea of inserting guard bands between the signals which reduces the design complexities of perfect ADC and sharp cut off filters. Using this algorithm, valid sampling frequency ranges and corresponding IF values are calculated for down converting RF signals. The algorithm is tested for six RF signals of different wireless technologies which are integrated and simultaneously down converted using SDR based front end receiver and thus the system multiplies the base station capacity by a factor of six. The simulation results are obtained and shown in this paper which proves that the algorithm developed works well for most of the wireless technologies. 展开更多
关键词 band pass Filter Radio Frequency Reconfigurable Architecture Sampling Software Defined Radio Wireless Communication
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CFOA Based Band Pass and Band Stop Ladder Filter—A New Configuration
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作者 Praween K. Sinha Neelam Sharma +1 位作者 Simran Agarwal Sudipto Saha 《Circuits and Systems》 2016年第1期29-42,共14页
A new technique for the conversion of ladder based filter into CFOA based filter has been proposed. The technique uses signal flow graph and converts the existing LC ladder based filter into band pass & band stop ... A new technique for the conversion of ladder based filter into CFOA based filter has been proposed. The technique uses signal flow graph and converts the existing LC ladder based filter into band pass & band stop configurations. The design of band pass and band stop filter has been realized using the proposed technique. The proposed configuration is implemented using CFOA as an active device and all the capacitors are grounded. CFOA based circuits have greater linearity, high dynamic rate, high slew rate and high signal bandwidth. Simulation has been carried out using simulation software P Spice (v10.1). The simulation results have been demonstrated and discussed. 展开更多
关键词 CFOA-Current Feedback Operational Amplifier Ladder Filter Signal Flow Graph Current Mode Voltage Mode band pass Filter band Stop Filter
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Characterization of Simulator and Relative Spectral Responsivity Measurements of Photovoltaic Modules with Band Pass Filter Technique
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作者 Meric Seval Bazkir Ozcan 《Open Journal of Energy Efficiency》 2022年第3期71-87,共17页
One of the most important parameter used for the evaluation of the energy rating of PV modules is, their spectral responsivities which are the measure of electrical performance parameters per incident solar radiation.... One of the most important parameter used for the evaluation of the energy rating of PV modules is, their spectral responsivities which are the measure of electrical performance parameters per incident solar radiation. In this work, spectral responsivity measurements of a mono-crystalline, a poly-crystalline, a CIGS thin film and a bifacial module were measured using xenon-based flash type solar simulator system and a set of band pass filters. For the comprehensive characterization of parameters that may influence the spectral responsivity measurements, initially the simulator system was characterized both optically and thermally according to the IEC60904-9 and IEC60891 standard requirements. The optical characterizations in terms of spectral match, spatial non-uniformity and temporal instability indicate that the measured results (~3.0%, ~0.30% and ~0.20%) according to the IEC 60904-9 standard’s classification requirements correspond to A+A+A+ classes. Moreover, thermal characterizations in terms of the temperature uniformity show that over the 2 × 2 m area temperature uniformity of simulator system’s light distribution (1&ordm;C) is almost two times better than the IEC 60891 standard requirements (±2&ordm;C). Next, PV modules were electrically stabilized according to the IEC 61215-2 standard requirement’s (stability test) to reduce the fluctuations in their electrical performance parameters. Then, using the band pass filters, temperature controlled xenon-based solar simulator system and a reference PV module of the spectral responsivity of PV modules were measured from 400 nm to 1100 nm with 50 nm steps with relative uncertainty of 10<sup>-3</sup> level. 展开更多
关键词 Photovoltaic Modules RESPONSIVITY Solar Simulator band pass Filters
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无线传感节点中频域传输信号解调与控制方法
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作者 李国金 张映 南敬昌 《传感技术学报》 CAS CSCD 北大核心 2024年第8期1404-1410,共7页
为提高无线传感网络节点中的频域传输信号抗噪能力,优化前端镜像与噪声信号处理能力,以无线传感节点中的频域传输信号为研究对象,提出一种新的信号控制与解调方法。将无线传感信号输入设计的滤波器中,通过电容器、电阻、运算放大器相互... 为提高无线传感网络节点中的频域传输信号抗噪能力,优化前端镜像与噪声信号处理能力,以无线传感节点中的频域传输信号为研究对象,提出一种新的信号控制与解调方法。将无线传感信号输入设计的滤波器中,通过电容器、电阻、运算放大器相互协作完成信号滤波。引入前馈补偿通路组建两级节点信号解调线路,当输出传感信号功率超过标准,便可根据超出值,以前馈补偿的方式调节增益带宽积实现解调。在传感节点中外接一个校正电路,以校正电容调节码的方式,控制传感信号频域传输特性满足正常运行标准。仿真结果表明:在1 V的电源电压下,此滤波器中心频率为2 MHz,邻近信号抑制为55 dB,镜像信号抑制为33 dB,带内纹波为0.1 dB,通带电压增益为18 dB,工作电流为382μA。验证了所提方法具有较高的频域传输信号深度处理能力,且有助于实现无线传感网络高质量通信。 展开更多
关键词 无线传感网络 前馈补偿 信号解调 射频信号 带通滤波器 运算放大器
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一种提高变流器弱电网适应能力的虚拟阻抗控制策略 被引量:1
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作者 杨树德 李旺 +3 位作者 张新闻 蔡长虹 高雄鹰 周鑫 《电源学报》 CSCD 北大核心 2024年第2期158-166,共9页
弱电网下较大的电网等值电感可能引起并网变流器失稳,为此,首先,建立了并网变流器的阻抗模型,根据阻抗比判据分析了电网等值电感对并网变流器稳定性的影响;其次,针对并网变流器对感性电网阻抗适应能力较低的问题,提出了一种基于带通滤... 弱电网下较大的电网等值电感可能引起并网变流器失稳,为此,首先,建立了并网变流器的阻抗模型,根据阻抗比判据分析了电网等值电感对并网变流器稳定性的影响;其次,针对并网变流器对感性电网阻抗适应能力较低的问题,提出了一种基于带通滤波的虚拟阻抗控制策略,并研究了虚拟电阻值对变流器弱电网适应能力的影响,给出了虚拟电阻的选取原则;最后,搭建了系统仿真模型,仿真结果验证了文中理论分析的正确性和控制策略的有效性。 展开更多
关键词 弱电网 并网变流器 虚拟阻抗 带通滤波 稳定性
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小型化宽阻带5G半集总混合滤波器设计
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作者 王荔田 王之 +7 位作者 钱莉荣 李翠平 熊阳 李丹 何明 余保华 田亚会 李红浪 《电波科学学报》 CSCD 北大核心 2024年第4期769-776,共8页
面向5G无线通信应用设计了一款微带半集总混合宽阻带带通滤波器。该滤波器阻带可扩展至5G毫米波频段,具有优良的带外抑制、结构紧凑及尺寸小巧的特点。搭建了集总元件的高频电路模型并完成了集总元件的路-场联合仿真,最终实现了由十字... 面向5G无线通信应用设计了一款微带半集总混合宽阻带带通滤波器。该滤波器阻带可扩展至5G毫米波频段,具有优良的带外抑制、结构紧凑及尺寸小巧的特点。搭建了集总元件的高频电路模型并完成了集总元件的路-场联合仿真,最终实现了由十字加载谐振器混合集总LC并联谐振电路而成的宽阻带滤波器。滤波器的中心频率位于4.08 GHz,通频带覆盖3.96~4.2 GHz,位于目前用于5G室内覆盖的N77频段。滤波器具有极广的阻带抑制特性,且优于20 dB抑制水平的上阻带范围可达22 GHz。滤波器有效电路尺寸仅为5.125mm×7.625 mm,插入损耗水平较低(0.54 dB),具有良好的选择性,适用于高性能5G通信系统应用。 展开更多
关键词 集总混合微带 带通滤波器 带外抑制 小型化 5G
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全国产化微弱信号调理电路
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作者 赵星灵 张丹 +1 位作者 汪桂 刘海龙 《现代电子技术》 北大核心 2024年第20期27-32,共6页
为更好地处理微弱信号,提出一种新型的多通道信号前端调理模块。该模块不仅具有可编程增益功能,而且还整合了带通滤波器。在保证高输入阻抗和低噪声等关键性能的同时,提出一种全面而创新的调理模块设计方案。该方案的核心是采用可编程... 为更好地处理微弱信号,提出一种新型的多通道信号前端调理模块。该模块不仅具有可编程增益功能,而且还整合了带通滤波器。在保证高输入阻抗和低噪声等关键性能的同时,提出一种全面而创新的调理模块设计方案。该方案的核心是采用可编程增益放大电路,显著提高了模块在放大各类微弱信号时的适应性。此外,利用HC595系列芯片,实现了对增益的精确调控。该放大电路具备26 dB的固定增益和0~84 dB的可调增益范围,工作带宽设定在380~420 kHz。经过系统性能测试,结果表明该调理电路成功满足了设计目标的各项要求。 展开更多
关键词 微弱信号处理 调理电路 程控增益 带通滤波器 放大电路 运算放大器
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一种用于射频前端的谐波整形低功耗N通道滤波器
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作者 宋堃阳 蒋品群 +2 位作者 宋树祥 蔡超波 岑明灿 《无线电工程》 2024年第7期1795-1802,共8页
针对传统射频前端N通道滤波器功耗高,不能根据应用要求选择通过或抑制信号的高次谐波等问题,设计了一款谐波整形低功耗N通道滤波器。该滤波器通过添加具有适当权重的额外路径,可实现谐波抑制和整形的功能。同时,将本振Local Oscillator(... 针对传统射频前端N通道滤波器功耗高,不能根据应用要求选择通过或抑制信号的高次谐波等问题,设计了一款谐波整形低功耗N通道滤波器。该滤波器通过添加具有适当权重的额外路径,可实现谐波抑制和整形的功能。同时,将本振Local Oscillator(LO)信号的n次谐波信号作为时钟信号,降低LO信号频率,时钟信号发生器的动态功耗降低到原来的1/n。SMIC 180 nm CMOS工艺的后仿真结果表明,10通道带通滤波器的中心频率在0.1~6.0 GHz可调,增益为0~5 dB,噪声系数小于4.6 dB,功耗为3.5~6.0 mW,输入三阶交调点(Input 3rd-order Intermodulation Point,IIP3)大于10 dBm,3次和5次谐波抑制分别大于65、90 dB,表明该滤波器具有谐波抑制和谐波整形的功能,且具有较低的功耗。 展开更多
关键词 N通道滤波器 带通滤波器 谐波整形 谐波抑制 低功耗
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三种典型水声信号类型检测特性对比分析
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作者 许佳丽 高飞 +2 位作者 范龙 李国富 甘忠良 《海洋测绘》 CSCD 北大核心 2024年第4期58-63,共6页
水声信号的选择是传播损失调查工作中的重要环节,为进一步研究不同信号类型的检测性能,通过仿真研究与试验数据分析,对CW、扫频、伪随机编码这3种典型的水声信号类型检测性能进行了对比研究。其中,仿真研究使用射线理论模型中Bellhop程... 水声信号的选择是传播损失调查工作中的重要环节,为进一步研究不同信号类型的检测性能,通过仿真研究与试验数据分析,对CW、扫频、伪随机编码这3种典型的水声信号类型检测性能进行了对比研究。其中,仿真研究使用射线理论模型中Bellhop程序计算宽带频域声信号,经傅里叶合成技术转化为时频声信号;信号检测性能分析采用带通滤波、匹配滤波和短时傅里叶变换方法开展。经对比后发现扫频信号和伪随机编码信号经匹配滤波后的信号主峰时频宽度小、幅度大,旁瓣小,易于区分,可获取信号多途到达结构,这对后续分析工作中反推反射系数有一定的优势。 展开更多
关键词 水声信号检测 水声信号类型 匹配滤波 带通滤波 短时傅立叶变换
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基于改进EMD-Kurtogram法的滚动轴承早期故障诊断研究 被引量:1
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作者 赵超阳 陈亮 +2 位作者 韦隆 韩思源 李培军 《现代电子技术》 北大核心 2024年第4期159-163,共5页
实现滚动轴承早期故障准确诊断的关键是得到故障部位有效振动信息,但实际工程中所采集到的轴承振动信号常含有噪声、干扰成分,给有效信息的选择带来了困难。带通滤波是解决该问题的有效方法之一,但不合理的滤波器参数会降低诊断结果的... 实现滚动轴承早期故障准确诊断的关键是得到故障部位有效振动信息,但实际工程中所采集到的轴承振动信号常含有噪声、干扰成分,给有效信息的选择带来了困难。带通滤波是解决该问题的有效方法之一,但不合理的滤波器参数会降低诊断结果的准确性。为此,提出一种基于改进EMD-Kurtogram法的滚动轴承早期故障诊断方法。该方法首先对EMD方法处理后的采样信号进行重构,再根据快速谱峭度图得到带通滤波器所需要的最优参数,最后经过带通滤波及时频域分析得到故障频率。通过实验平台验证及相关算法的对比得出,所提方法得到的故障倍频信息更加充分、清晰,所含噪声干扰更少,证明了该方法的有效性和先进性。 展开更多
关键词 滚动轴承 故障诊断 改进EMD-Kurtogram法 带通滤波 EMD信号处理 信号重构 谱峭度
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