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Amplifier & attenuator Effect of GSS: An Enhanced General Decision Making Model

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Systems Science and Systems Engineering 1997年第4期7卷 13-23页

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Ａｍｐｌｉｆｉｅｒ＆ＡｔｅｎｕａｔｏｒＥｆｅｃｔｏｆＧＳＳ：ＡｎＥｎｈａｎｃｅｄＧｅｎｅｒａｌＤｅｃｉｓｉｏｎＭａｋｉｎｇＭｏｄｅｌＲｅｃｅｉｖｅｄＭａｒｃｈ２８，１９９６ＨＵＡＮＧＷｅｉ１，ＸＩＹ．Ｍ．２，ＷＥＩＫ．Ｋ．１，３ａｎｄＴＡＮＢｅｒｎａ...

关键词： GSS Effect attenuator Amplifier An

A modulator using RF CMOS T-type attenuator for TH-UWB communications

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Journal of Southeast University(English Edition) 2009年第4期25卷 435-438页

作者：段吉海王志功李智群东南大学集成电路学院南京210096 桂林电子科技大学信息与通信学院桂林541004 东南大学射频与光电集成电路研究所南京210096

The insertion loss （IL） of a T-type attenuator is theoretically analyzed. A T-type RF （ radio frequency） CMOS （ complementary metal-oxide-semiconductor ） attenuator is designed as an on-off keying（OOK） modulator in a time-hopping ultra wide-band （TH-UWB）communication with a carrier frequency of 4 GHz. In the topology of the OOK modulator circuit, there are three parts, an oscillator with an oscillating frequency of 4 GHz, a T-type attenuator constructed by RF CMOS transistors, and an output impedance matching network with a L-type LC structure. The modulator is controlled by a time-hopping pulse position modulation（TH-PPM） signal. The envelope of the modulated signal varies with the amplitude of the controlling signal. Meanwhile, an output matching network is also designed to match a 50 Ω load. In 0. 18 μm RF CMOS technology, a modulator is designed and simulated. The implemented modulator chip has 65 mV of the output amplitude at a 50 fl load from a 1.8 V supply, and the return loss （ S11 ） at the output port is less than - 10 dB. The chip size is 0. 7 mm × 0. 8 mm, and the power consumption is 12. 3 mW.

关键词： attenuator insertion loss ( IL ) on-off keying (OOK) RF CMOS

Optimal Design of a Multibody Self-Referencing attenuator

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Journal of Power and Energy Engineering 2015年第9期3卷 59-69页

作者： Dongmei Zhou Jennifer A. Eden Department of Mechanical Engineering California State University Sacramento CA USA

The purpose of this paper is to determine the optimal size and number of tubes for a generic attenuator that is similar to Pelamis P2, the wave energy converter. Simulations using ANSYS Workbench, Design Modeler, and AQWA are performed to study the energy absorption at the nodes between the tubes. The analysis is limited to linearized hydrodynamic fluid waves loading on floating bodies by employing three-dimensional radiation/diffraction theory in regular waves in the frequency domain. Three sets of tests are conducted by varying total tube number, each tube length and the order of tubes with different lengths. After a systematic study in the frequency domain, the optimal size and number of the genetic attenuator is recommended.

关键词： attenuator Pelamis Extraction Efficiency & Power Numerical Simulation Parametric Study

Offset-free DC-coupled analog frontend circuit for high-dynamicrange signals

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Nuclear Science and Techniques 2020年第4期31卷 29-36页

作者： Ya-Fei Du Jun Wu Chen Yuan Chuan-Fei Zhang Yi-Nong Liu Department of Engineering Physics Tsinghua UniversityBeijing 100084China Institute of Nuclear Physics and Chemistry China Academy of Engineering PhysicsMianyang 621900China

The analog frontend(AFE)coupling circuit is a crucial processing element for data acquisition systems based on analog-to-digital converters(ADCs).Currently,high-speed and high-resolution ADCs are predominantly designed with differential input *** highspeed ADC drivers are mainly AC-coupled by employing transformers(Baluns)or fully differential amplifiers(FDAs)with blocking ***,the results of this study indicate that a certain degree of DC offset error exists and manifests itself as the baseline error in the presence of power dividers connecting several DC-coupled channels that implement high-dynamic-range(HDR)signal *** study involves a theoretical analysis and explanation of the baseline offset *** offset error can potentially lead to unexpected out-of-range issues for sampling devices,including high-speed ADCs and switched capacitor array ***-performance FDAs are adopted,and an offset-free DC-coupled AFE circuit is proposed to address the aforementioned issue using twostage amplification and a resistive *** proposed methodology is verified via circuit simulations and hardware ***,the baseline offset problem can be accurately solved using the proposed circuit by minimizing the neglectable *** proposed circuit facilitates improvements in the high-precision measurement of HDR signals in many nuclear physics experiments and some applications in the DC-coupling scheme with FDAs involving resistive power dividers.

关键词： Offset-free DC-coupled Two-stage amplification Resistive attenuator High-dynamic-range

A CMOS 4-Element Ku-Band Phased-Array Transceiver

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Chinese Journal of Electronics 2022年第6期31卷 1092-1105页

作者： ZHANG Xiaoning YU Yiming ZHAO Chenxi LIU Huihua WU Yunqiu KANG Kai School of Electronic Science and Engineering University of Electronic Science and Technology of China

This paper presents a Ku-Band fully differential 4-element phased-array transceiver using a standard 180-nm CMOS process. Each transceiver is integrated with a 5-bit phase shifter and 4-bit attenuator for high-resolution radiation manipulation. The front-end system adopts time-division mode, and hence two low-loss T/R switches are included in each channel. At room temperature, the measured root-mean-square（RMS） phase error is less than 5.5°. Furthermore, the temperature influence on passive switched phase shifters is ***, an extra phase-shifting cell is developed to calibrate phase error varying with the operating temperatures. With the calibration, the RMS phase error is reduced by 7° at-45 ℃, and 5.4° at 85 ℃. The RMS amplitude error is less than 0.92 dB at 15-18 GHz. In the RX mode, the tested gain is 9.6±1.1 dB at 16.5 GHz with a noise figure of 10.9 dB, and the input P1dB is-15 dBm,while the single-channel's gain and output P1dB in the TX mode are 11.3±0.4 dB and 9.4 dBm at 16.1 GHz, respectively. The whole chip occupies an area of 5×4.2 mm2and the measured isolation between each two adjacent channels is lower than-23.1 dB.

关键词： microwave switches passive networks time-division mode CMOS fully differential 4-element ku-band phased-array transceiver attenuator attenuators RMS amplitude error passive switched phase shifters high-resolution radiation manipulation calibration MMIC phase shifters front-end system TX mode field effect MMIC extra phase-shifting cell RMS phase error CMOS integrated circuits measured root-mean-square phase error RX mode low-loss T/R switches radio transceivers room temperature standard CMOS process

Measurement of the half-life of ^(79)Se with accelerator mass spectrometry

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Chinese Physics C 2014年第10期38卷 65-68页

作者：窦亮姜山王晓波董克君武绍勇杨旭冉王小明蓝小淅夏清良何明 Department of Nuclear Physics China Institute of Atomic Energy College of Physics Science and Technology Guangxi University

The accelerator mass spectrometry（AMS） is an effective method for the determination of the half-life of long-lived radionuclides. In this paper, we report a method for measurement of the half-life of ^79Se. The number of ^79Se atoms was determined from measured ^79Se/Se absolute ratios with the AMS system at the China Institute of Atomic Energy and the decay rate of ^79Se was determined by counting the emitted β-rays with a liquid scintillation spectrometer. The major improvements of our measurements include using the high abundance of an ^79Se sample which was cooled for many years to exclude the interference of short-lived nuclides, the extraction of SeO-2molecular ions, that results in a suppression of the ^79Br background by as much as about five orders of magnitude. Also, an AMS measurement of the absolute ratio of ^79Se/Se was developed to avoid systematic errors. The results show that ^79Se/Se is（2.35±0.12）×10^-7in the reference sample and the radioactivity of ^79Se is（1.24±0.05） Bq/g, so the half-life of ^79Se is（2.78±0.18）×10^5a.

关键词： ^79Se half-life AMS attenuator

A cancer cell turn-on protein-CuSMn nanoparticle as the sensor of breast cancer cell and CH_3O-PEG-phosphatide

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Chinese Chemical Letters 2018年第10期29卷 1528-1532页

作者： Huan Yang Hongjuan Liang Yuwen Xie Qiuyun Chen School of Chemistry and Chemical Engineering Jiangsu University

Cancer activated protein-inorganic nanoparticles can be cancer targeting turn-on imaging and therapy agents. Although various techniques were successfully employed for development of hybrid proteininorganic nanoparticles, cancer cell activated protein-inorganic nanoparticles have been ***, a cancer cell responsive nanoparticle（PDAMn-CuS@BSA-FA, NPs） was constructed and characterized. It is found that the quenching interaction of dyes（PDA） and central metal in NPs can be adjusted by CH_3O-PEG-phosphatide or the cancer cells, hence, NPs showed turn-on fluorescence emission with the titration of CH_3O-PEG-phosphatide. In particular, breast cancer cells lysis can switch on the green emission greatly, while normal cells show less effect. Breast cancer cells turn-on fluorescence imaging and mitochondria targeting imaging demonstrate that the NPs can sense breast cancer cells and enter mitochondria. Therefore, NPs can be both breast cancer targeting nanosensor.

关键词： Activable sensor Protein-inorganic nanoparticle Cancer CH3O-PEG-phosphatide attenuator

Attenuation characteristics of monolayer graphene by Pi-and T-networks modeling of multilayer microstrip line

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Journal of Semiconductors 2017年第9期38卷 25-30页

作者： Pulkit Sharma Sumit Pratap Singh Kamlesh Patel Department of Electronic Science University of Delhi South CampusBenito Juarez RoadNew Delhi-110021India

The impedances of Pi- and T- networks are obtained from the measured S-parameters of the multilayer microstrip line by modeling as an attenuator. The changes in impedances have been analyzed for the properties of various superstrates at the microwave ranges. With graphene on glass and graphene on quartz loadings, the impedances have increased and shifted towards lower frequency more in Pi-network than T-network modeling. This shift has become more prominent at higher frequency for the graphene on glass than graphene on quartz. A little increase in attenuation is found for graphene on glass or quartz than bare glass and quartz. The present study can be extended to obtain attenuation characteristic of any thin film by simple experimental method in the microwave frequencies.

关键词： microstrip line attenuator graphene S-parameters impedance

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一种宽带电调衰减器的设计

一种宽带电调衰减器的设计