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Federated Machine Learning Based Fetal Health Prediction Empowered with Bio-Signal Cardiotocography
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作者 Muhammad Umar Nasir Omar Kassem Khalil +4 位作者 Karamath Ateeq Bassam SaleemAllah Almogadwy Muhammad Adnan Khan Muhammad Hasnain Azam Khan Muhammad Adnan 《Computers, Materials & Continua》 SCIE EI 2024年第3期3303-3321,共19页
Cardiotocography measures the fetal heart rate in the fetus during pregnancy to ensure physical health because cardiotocography gives data about fetal heart rate and uterine shrinkages which is very beneficial to dete... Cardiotocography measures the fetal heart rate in the fetus during pregnancy to ensure physical health because cardiotocography gives data about fetal heart rate and uterine shrinkages which is very beneficial to detect whether the fetus is normal or suspect or pathologic.Various cardiotocography measures infer wrongly and give wrong predictions because of human error.The traditional way of reading the cardiotocography measures is the time taken and belongs to numerous human errors as well.Fetal condition is very important to measure at numerous stages and give proper medications to the fetus for its well-being.In the current period Machine learning(ML)is a well-known classification strategy used in the biomedical field on various issues because ML is very fast and gives appropriate results that are better than traditional results.ML techniques play a pivotal role in detecting fetal disease in its early stages.This research article uses Federated machine learning(FML)and ML techniques to classify the condition of the fetus.This study proposed a model for the detection of bio-signal cardiotocography that uses FML and ML techniques to train and test the data.So,the proposed model of FML used numerous data preprocessing techniques to overcome data deficiency and achieves 99.06%and 0.94%of prediction accuracy and misprediction rate,respectively,and parallel the proposed model applying K-nearest neighbor(KNN)and achieves 82.93%and 17.07%of prediction accuracy and misprediction accuracy,respectively.So,by comparing both models FML outperformed the KNN technique and achieved the best and most appropriate prediction results as compared with previous studies the proposed study achieves the best and most accurate results. 展开更多
关键词 CARDIOTOCOGRAPHY ML FML fetal disease bio-signal
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Wireless Preamplifier for the Specimen Current Mode Detector in a SEM
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作者 Valentin G. Dyukov 《Optics and Photonics Journal》 2024年第2期23-28,共6页
Using a scanning electron microscope (SEM) in the back-scattered electron (BSE) mode the composition of multi-element specimens may be determined based on the strong dependence of emission coefficient η on the averag... Using a scanning electron microscope (SEM) in the back-scattered electron (BSE) mode the composition of multi-element specimens may be determined based on the strong dependence of emission coefficient η on the average atomic number of elements Z. The output video signal of the usual BSE detectors is produced from their sensors, and the larger proportion of high-energy electrons with modified spectrum is added. Since η = is/ip (is and ip currents of specimen and probe), better accuracy must be achieved by direct measurements those currents on the specimen surface. Here, an experimental model of a current detector for a presented specimen is described. The cage is mounted on the carousel of the moving specimen stage. The input of the preamplifier is connected to the specimen holder in the form of a disk, the diameter of which is 12 mm. When the probe along its surface scanned, the input potential begins to pulsate with a negative polarity. The output of this preamplifier is connected to a small light-emitting diode, which creates intensity-modulated radiation in the chamber. Thus created the light video signal will be picked up by the photomultiplier of the E-T detector. The modes of true SE and BSE are set by applying tens bias volts of various polarities to the specimens or the cage itself. 展开更多
关键词 Scanning Electron Microscopy Backscattered Electron Imaging Wireless Specimen Current preamplifier Universal (SE/BSE) Dyukov Detector
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Simulation of a Monolithic Integrated CMOS Preamplifier for Neural Recordings 被引量:2
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作者 隋晓红 刘金彬 +2 位作者 顾明 裴为华 陈弘达 《Journal of Semiconductors》 EI CAS CSCD 北大核心 2005年第12期2275-2280,共6页
A monolithic integrated CMOS preamplifier is presented for neural recording applications. Two AC-coupied capacitors are used to eliminate the large and random DC offsets existing in the electrode-electrolyte interface... A monolithic integrated CMOS preamplifier is presented for neural recording applications. Two AC-coupied capacitors are used to eliminate the large and random DC offsets existing in the electrode-electrolyte interface. Diode-connected nMOS transistors with a negative voltage between the gate and source are candidates for the large resistors necessary for the preamplifier. A novel analysis is given to determine the noise power spectral density. Simulation results show that the two-stage CMOS preamplifier in a closed-loop capacitive feedback configuration provides an AC in-band gain of 38.8dB,a DC gain of 0,and an input-referred noise of 277nVmax, integrated from 0. 1Hz to 1kHz. The preamplifier can eliminate the DC offset voltage and has low input-referred noise by novel circuit configuration and theoretical analysis. 展开更多
关键词 preamplifier DC offset input-referred noise
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A 10Gb/s GaAs PHEMT High Gain Preamplifier for Optical Receivers
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作者 焦世龙 杨先明 +5 位作者 赵亮 李辉 陈镇龙 陈堂胜 邵凯 叶玉堂 《Journal of Semiconductors》 EI CAS CSCD 北大核心 2007年第12期1902-1911,共10页
A high gain cascade connected preamplifier for optical receivers is developed with 0.5μm GaAs PHEMT technology from the Nanjing Electronic Devices Institute. To begin with, the transimpedance amplifier has a -3dB ban... A high gain cascade connected preamplifier for optical receivers is developed with 0.5μm GaAs PHEMT technology from the Nanjing Electronic Devices Institute. To begin with, the transimpedance amplifier has a -3dB bandwidth of 10GHz, with a small signal gain of around 9dB. The post-stage distributed amplifier (DA) has a -3dB bandwidth of close to 20GHz,with a small signal gain of around 12dB. As a whole,the cascade preamplifier has a measured small signal gain of 21.3dB and a transimpedance of 55.3dBΩ in a 50Ω system. With a higher signal-to-noise ratio than that of the TIA and a markedly improved waveform distortion compared with that of the DA, the measured output eye diagram for 10Gb/s NRZ pseudorandom binary sequence is clear and symmetric. 展开更多
关键词 GaAs PHEMT optical receiver preamplifier eye diagram CASCADE
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10Gb/s GaAs PHEMT Current Mode Transimpedance Preamplifier for Optical Receiver
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作者 焦世龙 叶玉堂 +4 位作者 陈堂胜 冯欧 蒋幼泉 范超 李拂晓 《Journal of Semiconductors》 EI CAS CSCD 北大核心 2007年第1期24-30,共7页
A single power supply common-gate (CG) current mode transimpedance preamplifier (TIA) is developed with a 0.5μm GaAs PHEMT process. The amplifier has a measured - 3dB bandwidth of 7. 5GHz and a transimpedance gai... A single power supply common-gate (CG) current mode transimpedance preamplifier (TIA) is developed with a 0.5μm GaAs PHEMT process. The amplifier has a measured - 3dB bandwidth of 7. 5GHz and a transimpedance gain of 45dBΩ. Both the input and output voltage standing wave ratios (VSWR) are less than 2 within the bandwidth. The equivalent input noise current spectral density varies from 14.3 to 22pA/√Hz, with an average value of 17. 2pA/√Hz. Having a timing jitter of 14ps and eye amplitude of about 138mV,the measured output eye diagram for 10Gb/s NRZ pseudorandom binary sequence (PRBS) is clear and satisfactory. 展开更多
关键词 GaAs PHEMT current mode preamplifier noise figure eye diagram
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Design of 10 Gbit/s burst-mode transimpedance preamplifier for PON systems
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作者 顾皋蔚 朱恩 林叶 《Journal of Southeast University(English Edition)》 EI CAS 2012年第4期398-403,共6页
A 10 Gbit/s burst-mode preamplifier is designed for passive optical networks (PONs). To achieve a high dynamic range and fast response, the circuit is DC coupled, and a feed-back type peak detector is designed to pe... A 10 Gbit/s burst-mode preamplifier is designed for passive optical networks (PONs). To achieve a high dynamic range and fast response, the circuit is DC coupled, and a feed-back type peak detector is designed to perform auto-gaincontrol and threshold extraction. Regulated cascade (RGC) architecture is exploited as the input stage to reduce the input impedance of the circuit and isolate the large parasitic capacitance including the photodiode capacitance from the determination pole, thus increasing the bandwidth. This preamplifier is implemented using the low-cost 0. 13 ixm CMOS technology. The die area is 425 μm × 475 μm and the total power dissipation is 23.4 mW. The test results indicate that the preamplifier can work at a speed from 1.25 to 10.312 5 Gbit/s, providing a high transimpedance gain of 64.0 dBΩ and a low gain of 54. 6 dBl2 with a dynamic input range of over 22.9 dB. The equivalent input noise current is 23. 4 pA/ Hz1/2. The proposed burst amplifier satisfies related specifications defined in 10G-EPON and XG-PON standards. 展开更多
关键词 BURST-MODE passive optical network (PON) transimpedance preamplifier regulated cascade (RGC) peak detector auto-gain-control threshold extraction
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Compact 16-channel integrated charge-sensitive preamplifier module for silicon strip detectors 被引量:4
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作者 Dong-Xi Wang Cheng-Jian Lin +6 位作者 Lei Yang Nan-Ru Ma Li-Jie Sun Feng Yang Hui-Ming Jia Fu-Peng Zhong Pei-Wei Wen 《Nuclear Science and Techniques》 SCIE CAS CSCD 2020年第5期36-43,共8页
In this study,a compact 16-channel integrated charge-sensitive preamplifier named the smart preamplifier(SPA)was developed to support the large-scale detector array used in modern nuclear physics experiments.Two types... In this study,a compact 16-channel integrated charge-sensitive preamplifier named the smart preamplifier(SPA)was developed to support the large-scale detector array used in modern nuclear physics experiments.Two types of SPA,namely SPA02 and SPA03(with external field effect transistor),have been manufactured to match silicon detectors with small and large capacitances,respectively.The characteristics of the SPA include fast response of typically less than 6 ns for pulse rising time and low equivalent noise of 1.5 keV at zero input capacitance.The energy sensitivity and pulse decay time can be easily adjusted by changing the feedback capacitance Cfand resistance Rfin various applications.A good energy resolution of 24.4 keV for 5.803-MeV alpha particles from 244 Cm was achieved using a small-sized Si-PIN detector;for the silicon strip detectors in the test with the alpha source,a typical energy resolution of 0.6–0.8%was achieved.The integrated SPA has been employed in several experiments of silicon strip detectors with hundreds of channels,and a good performance has been realized. 展开更多
关键词 Silicon STRIP DETECTOR array 16-Channel INTEGRATED charge-sensitive preamplifier preamplifier circuit design preamplifier performance
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Design of a Preamplifier Card for the Photomultiplier Tubes of a Gamma Camera 被引量:2
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作者 Jorge Luis Domínguez Martínez 《Journal of Physical Science and Application》 2018年第1期46-54,共9页
The service provided by the GC(Gamma Cameras)in the Nuclear Medicine departments fails because of their breakdown,generally due to the associated electronics and not to the physical detection components.For this reaso... The service provided by the GC(Gamma Cameras)in the Nuclear Medicine departments fails because of their breakdown,generally due to the associated electronics and not to the physical detection components.For this reason,it was decided to develop an electronic system that allows the recovery and optimization of disused GC,starting with the design of the preamplifier for a PMT(photomultiplier tube).The circuit was designed and simulated and the list of components necessary for the construction of the preamplifier was generated,as well as the printed circuit board was designed for its assembly.By simulating the preamplifier this worked in linear mode.This determines that the amplitude of the output signal is proportional to the amount of charge delivered by the detector.This card allows an automatic adjustment of the signals of the PMT as do the modern GC. 展开更多
关键词 GAMMA camera nuclear MEDICINE PHOTOMULTIPLIER tube preamplifier CUBA
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Design and simulation of charge sensitive preamplifier with CMOS FET implemented as feedback capacitor C_(fp) 被引量:3
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作者 WEMBE TAFO Evariste SU Hong +1 位作者 GAO Yanni WU Ming 《Nuclear Science and Techniques》 SCIE CAS CSCD 2008年第4期241-245,共5页
In this paper,to design a new preamplifier for optimum performances with charged-particle or heavy-ion detectors,the CMOS FET is implemented as a feedback capacitor Cfp,so that the entire system should be built only w... In this paper,to design a new preamplifier for optimum performances with charged-particle or heavy-ion detectors,the CMOS FET is implemented as a feedback capacitor Cfp,so that the entire system should be built only with MOSFET. This work is a revolution design because to realize an ASIC for a preamplifier circuit,the capacitor will also be included. We succeed after a simulation to maintain a rise time less than 3 ns,the output resistance less than 94 ? and the linearity almost good. 展开更多
关键词 电流放大器 粒子探测技术 模拟实验 放射学
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A low noise charge sensitive preamplifier with switch control feedback resistance 被引量:3
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作者 WEMBE TAFO Evariste SU Hong +2 位作者 PENG Yu WU Ming QIAN Yi 《Nuclear Science and Techniques》 SCIE CAS CSCD 2008年第1期39-44,共6页
In this paper, the design and analysis of a new low noise charge sensitive preamplifier for silicon strip, Si(Li), CdZnTe and CsI detectors etc. with switch control feedback resistance were described, the entire syste... In this paper, the design and analysis of a new low noise charge sensitive preamplifier for silicon strip, Si(Li), CdZnTe and CsI detectors etc. with switch control feedback resistance were described, the entire system to be built using the CMOS transistors. The circuit configuration of the CSP proposed in this paper can be adopted to develop CMOS-based Application Specific Integrated Circuit further for Front End Electronics of read-out system of nuclear physics, particle physics and astrophysics research, etc. This work is an implemented design that we succeed after a simulation to obtain a rise time less than 3ns, the output resistance less than 94? and the linearity almost good. 展开更多
关键词 电流放大器 粒子探测技术 开关 反射电阻
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High-Stability High-Energy Picosecond Optical Parametric Chirped Pulse Amplifier as a Preamplifier in Nd:Glass Petawatt System for Contrast Enhancement 被引量:1
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作者 黄庭瑞 潘雪 +3 位作者 张鹏 王江峰 欧阳小平 李学春 《Chinese Physics Letters》 SCIE CAS CSCD 2017年第6期53-57,共5页
We demonstrate a novel picosecond optical parametric preamplification to generate high-stability, high-energy and high-contrast seed pulses. The 5ps seed pulse is amplified from 60pJ to 300μJ with an 8.6ps/ 3mJ pump ... We demonstrate a novel picosecond optical parametric preamplification to generate high-stability, high-energy and high-contrast seed pulses. The 5ps seed pulse is amplified from 60pJ to 300μJ with an 8.6ps/ 3mJ pump laser in a signal stage of short pulse non-collinear optical parametric chirped pulse amplification. The total gain is more than 106 and the rms energy stability is under 1.35%. The contrast ratio is higher than 10s within a scale of 20ps before the main pulse. Consequently, the improvement factor of the signal contrast is approximately equal to the gain 106 outside the pump window. 展开更多
关键词 High-Stability High-Energy Picosecond Optical Parametric Chirped Pulse Amplifier as a preamplifier in Nd:Glass Petawatt System for Contrast Enhancement length Nd
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High Performance Bilinear Differential Preamplifier for BESⅢ Time-of-Flight System
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作者 李玉生 冼泽 安琪 《Plasma Science and Technology》 SCIE EI CAS CSCD 2005年第3期2875-2878,共4页
A time-of-flight (TOF) detector has been used in the BESIII experiment to provide charged particle identification. In this paper, we present a novel high performance differential amplifier, which has been designed for... A time-of-flight (TOF) detector has been used in the BESIII experiment to provide charged particle identification. In this paper, we present a novel high performance differential amplifier, which has been designed for amplifying the signals from the detectors. The preamplifier can amplify differential signals, which can help to eliminate the common mode pickup, and increase the signal-to-noise ratio (SNR). Bilinear gain is one of the features of this preamplifier, which greatly increases the dynamic range and avoids the dead time of the preamplifier. In order to describe the bilinear gain, a 4-parameter function is developed. And this 4-parameter function can also be used in the calibration of the time walk caused by the amplitude due to the bilinear gain. The preamplifier has a gain about 10V/V with a small signal and about 1.0V/V with a large signal. The rise time of the preamp is less than 2 ns. 展开更多
关键词 bilinear gain high performance preamplifier differential signal
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Digital FIR filter design for bio-signal processing system
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作者 Woojin Nam Guang Yang Seongsoo Lee 《Journal of Measurement Science and Instrumentation》 CAS 2013年第1期94-96,共3页
Recently,real-time processing systems for bio-signal of the muscles generated by the movement of the user have been developed.Finite impulse response(FIR)filter for bio-signal processing in bio-signal process systems ... Recently,real-time processing systems for bio-signal of the muscles generated by the movement of the user have been developed.Finite impulse response(FIR)filter for bio-signal processing in bio-signal process systems is composed of multiple multiplier and adder of high-area.This makes the chip area increase significantly.To solve this problem,a low-area digital FIR filter is proposed in this paper,which can reduce the chip area. 展开更多
关键词 low area digital finite impulse response(FIR)filter bio-signal processing
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Application of CMOS charge-sensitive preamplifier in triple-GEM detector
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作者 LAI Yong-Fang DENG Zhi +3 位作者 LI Yu-Lan LIU Yi-Nong LI Yuan-Jing LI Jin 《Nuclear Science and Techniques》 SCIE CAS CSCD 2006年第5期289-292,共4页
Among the various micro-pattern gas detectors (MPGD) that are available, the gas electron multiplier (GEM) detector is an attractive gas detector that has been used in particle physics experiments. However, the GEM de... Among the various micro-pattern gas detectors (MPGD) that are available, the gas electron multiplier (GEM) detector is an attractive gas detector that has been used in particle physics experiments. However, the GEM detector usually needs thousands of preamplifier units for its large number of micro-pattern readout strips or pads, which leads to considerable difficulties and complexities for front end electronics (FEE). Nowadays, by making use of complementary metal-oxide semiconductor (CMOS)-based application specific integrated circuit (ASIC), it is fea- sible to integrate hundreds of preamplifier units and other signal process circuits in a small-sized chip, which can be bound to the readout strips or pads of a micro-pattern particle detector (MPPD). Therefore, CMOS ASIC may provide an ideal solution to the readout problem of MPPD. In this article, a triple GEM detector is constructed and one of its readout strips is connected to a CMOS charge-sensitive preamplifier chip. The chip was exposed to an 55Fe source of 5.9 keV X-ray, and the amplitude spectrum of the chip was tested, and it was found that the energy resolution was approximately 27%, which indicates that the chip can be used in triple GEM detectors. 展开更多
关键词 气体电子倍增管探测器 互补金属氧化物半导体 专用集成电路 CMOS电路 电荷灵敏前置放大器 能量分辨率
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无线激光传输系统收发电路的设计与实现 被引量:1
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作者 李谦 庞俊奇 +4 位作者 刘瑞康 赵中梁 马宏帅 张磊 谭秋林 《仪表技术与传感器》 CSCD 北大核心 2024年第4期95-99,共5页
针对航天发动机、涡轮机等旋转部件的温度测量系统中的信号传输问题,以850 nm波长的红外光为载体,设计了基于FPGA的无线激光通信的数据传输系统。该系统由转子端的光发射模块、定子端的光接收模块、地面可视化设备3部分组成。此外,在前... 针对航天发动机、涡轮机等旋转部件的温度测量系统中的信号传输问题,以850 nm波长的红外光为载体,设计了基于FPGA的无线激光通信的数据传输系统。该系统由转子端的光发射模块、定子端的光接收模块、地面可视化设备3部分组成。此外,在前置放大电路中引入一个反馈电容,系统的开环增益曲线会增加一个极点做补偿以提升系统的稳定,并进行了仿真验证。在此基础之上,搭建实验系统对电路性能进行测试。通过仿真及实验验证,结果表明:设计的方案可以实现传输速率为40 Mbit/s的稳定传输,为旋转环境的动态监测技术中的无线数据传输提供了一种可行性方案。 展开更多
关键词 数据传输 无线激光通信 PIN等效模型 光检测电路 前置放大电路 反馈电容
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粒子辐射探测器专用电荷灵敏前置放大器扩量程技术研究
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作者 王游龙 于向前 +7 位作者 王玲华 陈鸿飞 施伟红 陈傲 王永福 杨芯 宗秋刚 邹鸿 《北京大学学报(自然科学版)》 EI CAS CSCD 北大核心 2024年第6期973-978,共6页
专用集成前置放大器RENA3因噪声低而广泛用做粒子辐射探测器的前置放大器,但RENA3的最大输入电荷量限制了其量程。针对这一问题,提出一种通过在RENA3的输入端并联电容的方法来扩展量程,并对该扩量程技术方案进行理论分析、PSpice仿真分... 专用集成前置放大器RENA3因噪声低而广泛用做粒子辐射探测器的前置放大器,但RENA3的最大输入电荷量限制了其量程。针对这一问题,提出一种通过在RENA3的输入端并联电容的方法来扩展量程,并对该扩量程技术方案进行理论分析、PSpice仿真分析和实验验证。实验结果与理论分析和数值模拟结果相吻合,由此验证了所提出方法的可行性。该方法可适用于其他专用集成前置放大器的量程扩展。 展开更多
关键词 专用集成前置放大器 量程扩展 RENA3
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低噪声水声信号前置放大器设计 被引量:2
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作者 程华 陈科君 王旭光 《湖北大学学报(自然科学版)》 CAS 2024年第2期282-288,共7页
水下信息的发送与接收主要通过声信号的传播,水听器作为常用的水声信号接收装置,需要前置放大器来提高所获取信号的质量。文中选用AD8421仪表放大器芯片与OP2177精密运算放大器芯片设计了一种低噪声水声信号前置放大器,该电路增益为26 ... 水下信息的发送与接收主要通过声信号的传播,水听器作为常用的水声信号接收装置,需要前置放大器来提高所获取信号的质量。文中选用AD8421仪表放大器芯片与OP2177精密运算放大器芯片设计了一种低噪声水声信号前置放大器,该电路增益为26 dB,工作带宽为100 Hz~20 kHz,输出信号为差分形式,同时具有小体积、低功耗的特点。通过连接某型压电水听器,测试了电路工作性能以及对水听器信号的调理效果。实测结果表明,该前置放大器能满足设计技术指标要求,在实际工作中取得了良好的效果。 展开更多
关键词 水声信号调理 前置放大器 低噪声 有源滤波器 带通滤波器
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用于扫描隧道显微镜的低噪声前置电流放大器
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作者 唐海涛 米壮 +4 位作者 王文宇 唐向前 叶霞 单欣岩 陆兴华 《物理学报》 SCIE EI CAS CSCD 北大核心 2024年第13期20-27,共8页
前置电流放大器是扫描隧道显微镜的重要部件之一,其性能对于扫描隧道显微镜系统的基本操作及新功能开发至关重要.本文详细分析了影响前置电流放大器性能的因素,通过筛选噪声极低的运放芯片和电路结构优化,设计了一款针对扫描隧道显微镜... 前置电流放大器是扫描隧道显微镜的重要部件之一,其性能对于扫描隧道显微镜系统的基本操作及新功能开发至关重要.本文详细分析了影响前置电流放大器性能的因素,通过筛选噪声极低的运放芯片和电路结构优化,设计了一款针对扫描隧道显微镜系统的前置电流放大器.该放大器最灵敏档位(1 GΩ)的噪声低至4 fA/(Hz)1/2,带宽为2.3 kHz,具有10 MΩ,100 MΩ和1 GΩ三个测量量程并且可以通过控制信号实现自动切换,测量范围覆盖pA—μA量级的隧穿电流.利用该前置电流放大器展示了扫描隧道显微镜系统的主要功能,包括表面形貌表征、扫描隧道谱测量以及原子搬运,并探索了隧穿电流中散粒噪声的测量.通过散粒噪声随隧穿电流的变化关系,得到隧穿结中散粒噪声的法诺因子约等于1,验证了简单金属隧穿结中电子隧穿满足泊松过程,为表面电子关联体系的高精度表征提供了基础. 展开更多
关键词 扫描隧道显微镜 前置电流放大器 散粒噪声
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MEMS压电矢量水听器低噪声前置放大电路
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作者 邓威 樊青青 +2 位作者 李俊红 马军 孔超 《压电与声光》 CAS 北大核心 2024年第4期550-554,共5页
等效自噪声是微机电系统(MEMS)压电矢量水听器重要的性能指标,前置放大电路的噪声是其主要来源之一。为降低MEMS压电矢量水听器的自噪声,设计了一种低噪声前置放大电路。采用双JFET并联电路结构,辅以合适的偏置电路,对不同噪声源进行理... 等效自噪声是微机电系统(MEMS)压电矢量水听器重要的性能指标,前置放大电路的噪声是其主要来源之一。为降低MEMS压电矢量水听器的自噪声,设计了一种低噪声前置放大电路。采用双JFET并联电路结构,辅以合适的偏置电路,对不同噪声源进行理论分析,优化电路参数,最终实现了噪声性能较优的低噪声前置放大电路的设计与制备。测试结果表明,在MEMS压电矢量水听器的工作频带内,低噪声前置放大电路信号放大无失真,电压增益为43.8d B,等效输入噪声电压谱密度为0.7nV√Hz@1 kHz其噪声性能较国内外同类型的放大电路具有一定优势。 展开更多
关键词 等效自噪声 MEMS压电矢量水听器 前置放大电路 1/f噪声 噪声电压谱密度
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A low noise and wide dynamic range preamplifier for HPGe detectors
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作者 Jiajun Hao Zhengxi Cheng +2 位作者 Xiangke Ye Li He Zhi Deng 《Radiation Detection Technology and Methods》 CSCD 2024年第3期1413-1421,共9页
Purpose HPGe detectors can be used for both dark matter search and neutrinoless double beta decay experiments.However,signal amplitudes of these two experiments are quite different.This paper presents the development ... Purpose HPGe detectors can be used for both dark matter search and neutrinoless double beta decay experiments.However,signal amplitudes of these two experiments are quite different.This paper presents the development of a wide dynamic range CMOS preamplifier for HPGe detectors,which can also be used for low light level photon detection.Methods The structure of a dual-stage dual-gain amplifier was adopted to receive the signals with charges ranging from~0.01 fC to 500 fC.A novel“pre-reset”technique has been proposed to reduce the dead time ratio for large signals.A prototype chip was fabricated and tested.Results A minimum ENC of 43 electrons has been achieved for the high-gain channel at 77 K and the maximum charge of the input signal could be up to 500 fC for the low-gain channel,corresponding to a dynamic range above 90 dB.Conclusions The dual-gain structure of the preamplifier and the“pre-reset”method have been successfully verified,which can be used for HPGe detectors for dark matter and neutrino experiments in the future. 展开更多
关键词 Low noise Wide dynamic range Charge sensitive preamplifier CMOS ASIC.Cryogenic electronics HPGe detector
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