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Jessie's Power in a Patriarchal Society in Night,Mother 被引量:1
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作者 薛冰 《海外英语》 2017年第15期175-176,共2页
Night,Mother is a famous play about female identification.It is about Jessie,a middle aged woman,who,through many years’struggle,decides to kill herself at nine o’clock in an ordinary night in her mother’s house.Je... Night,Mother is a famous play about female identification.It is about Jessie,a middle aged woman,who,through many years’struggle,decides to kill herself at nine o’clock in an ordinary night in her mother’s house.Jessie’s fighting for female identity and corresponding power would be analyzed.In the play,Jessie tries two ways to get her power,one by trying to imitating men to get accepted by patriarchal society,and the other by revolting outside resistance and insisting her pursuit of self rights and freedom. 展开更多
关键词 NIGHT MOTHER patriarchal Society power gaining IMITATION REVOLT
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Field plate structural optimization for enhancing the power gain of GaN-based HEMTs 被引量:1
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作者 张凯 曹梦逸 +5 位作者 雷晓艺 赵胜雷 杨丽媛 郑雪峰 马晓华 郝跃 《Chinese Physics B》 SCIE EI CAS CSCD 2013年第9期574-578,共5页
A novel source-connected field plate structure, featuring the same photolithography mask as the gate electrode, is proposed as an improvement over the conventional field plate (FP) techniques to enhance the frequenc... A novel source-connected field plate structure, featuring the same photolithography mask as the gate electrode, is proposed as an improvement over the conventional field plate (FP) techniques to enhance the frequency performance in GaN-based HEMTs. The influences of the field plate on frequency and breakdown performance are investigated simul- taneously by using a two-dimensional physics-based simulation. Compared with the conventional T-gate structures with a field plate length of 1.2 gm, this field plate structure can induce the small signal power gain at 10 GHz to increase by 5-9.5 dB, which depends on the distance between source FP and dramatically shortened gate FE This technique minimizes the parasitic capacitances, especially the gate-to-drain capacitance, showing a substantial potential for millimeter-wave, high power applications. 展开更多
关键词 GaN-based HEMTs breakdown characteristics field plates power gain
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CMOS Dual-Band Low Noise Amplifer
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作者 冯东 石秉学 《Journal of Semiconductors》 EI CAS CSCD 北大核心 2004年第9期1055-1060,共6页
A CMOS dual-band low noise amplifer (LNA) design is presented.The purpose of th is work is intended to substitute only one LNA for two individual LNA's in dual -band transceivers for applications such as wireless ... A CMOS dual-band low noise amplifer (LNA) design is presented.The purpose of th is work is intended to substitute only one LNA for two individual LNA's in dual -band transceivers for applications such as wireless local area network complying with both IEEE 802.11a and 802.11b/g.Dua l-band simultaneous input power and noise matching and load shaping are discuss ed.The chip is implemented in 0.25μm CMOS mixed and RF process.The measured pe rformance is summarized and discussed. 展开更多
关键词 low noise amplifier dual- band receiver power matching noise matching power gain voltage gain
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Simulation of x-ray transmission through an ellipsoidal capillary
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作者 林晓燕 李玉德 +1 位作者 孙天希 潘秋丽 《Chinese Physics B》 SCIE EI CAS CSCD 2010年第7期40-44,共5页
This paper develops a simulation program for x-ray transmission in an ellipsoidal capillary based on a ray-tracing method. The influence of the parameters of ellipsoidal capillary and x-ray energy on transmission effi... This paper develops a simulation program for x-ray transmission in an ellipsoidal capillary based on a ray-tracing method. The influence of the parameters of ellipsoidal capillary and x-ray energy on transmission efficiency, full width at half maximum and power density gain of x-ray beams through an ellipsoidal capillary was analysed by this program. It shows that the particular rules of the ellipsoidai capillary x-ray lens are different from the polycapillary lens. Furthermore, this analysis method can be applied to the optimized design of ellipsoidal capillary. 展开更多
关键词 ellipsoidal capillary transmission efficiency power density gain SIMULATION
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Pressure dependent modulation instability in photonic crystal fiber filled with argon gas
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作者 He-Lin Wang Ai-Jun Yang +2 位作者 XiaoLong Wang Bin Wu Yi Ruan 《Chinese Physics B》 SCIE EI CAS CSCD 2018年第9期338-341,共4页
By using the designed photonic crystal fiber filled with argon gas, the effect of gas pressure on modulation instability(MI) gain is analyzed in detail. The MI gain bandwidth increases gradually as the argon gas pre... By using the designed photonic crystal fiber filled with argon gas, the effect of gas pressure on modulation instability(MI) gain is analyzed in detail. The MI gain bandwidth increases gradually as the argon gas pressure rises from 1 P0 to 400 P0(P0 is one standard atmosphere), while its gain amplitude slightly decreases. Moreover, the increase of the incident light power also results in the increase of MI gain bandwidth in the Stokes or anti-Stokes region when the incident power increases from 1 W to 200 W. Making use of the optimal parameters including the higher argon gas pressure(400 P0) and the incident light power(200 W), we finally obtain a 100 nm broadband MI gain. These results indicate that controlling the MI gain characteristic by changing the argon gas pressure in PCF is an effective way when the incident light source is not easy to satisfy the requirement of practical application. This method of controlling MI gain can be used in optical communication and laser shaping. 展开更多
关键词 modulation instability gas pressure light power.broadband gain
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The Gain Dependence of the Power Transient in Raman Amplifier
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作者 Zheng Lei, Zhang Jiahong, Chen Zhangyuan, Wu Deming , Xu AnshiNational Laboratory on Local Fiber-Optic Networks and Advanced Optical Communication Systems, Electronics Department, Peking University, Beijing 100871, China, Tel: 86-010- 62763334, Email: zheng_lei@ele.pku.edu.cn Zhang Jiahong is with the 5th Institute of Telecommunications Technology of Ministry of Information Industry (MII, and Datang telecom technology Co., Ltd, Opitcal Communication Branch, Chengdu 610062, China 《光学学报》 EI CAS CSCD 北大核心 2003年第S1期409-410,共2页
It is observed that the amplitude of the power transient overshoot depends on the gain of the amplifier when the input signal powers are the same. The other system parameters, such as the input pump power and fiber le... It is observed that the amplitude of the power transient overshoot depends on the gain of the amplifier when the input signal powers are the same. The other system parameters, such as the input pump power and fiber length, have no effects on it. 展开更多
关键词 of LENGTH on BE it as The Gain Dependence of the power Transient in Raman Amplifier in
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A low power flexible PGA for software defined radio systems
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作者 李国锋 吴南健 《Journal of Semiconductors》 EI CAS CSCD 2012年第5期120-125,共6页
This paper proposes a new low power structure to improve the trade-off between the bandwidth and the power consumption of a programmable gain amplifier(PGA).The PGA consists of three-stage amplifiers, which includes... This paper proposes a new low power structure to improve the trade-off between the bandwidth and the power consumption of a programmable gain amplifier(PGA).The PGA consists of three-stage amplifiers, which includes a variable gain amplifier and DC offset cancellation circuits.The cutoff frequency of the DC offset cancellation circuits can be changed from 4 to 80 kHz.The chip was fabricated in 0.13μm CMOS technology. Measurement results showed that the gain of the PGA can be programmed from -5 to 60 dB.At the gain setting of 60 dB,the bandwidth can be tuned from 1 to 10 MHz,while the power consumption can be programmed from 850μA to 3.2 mA at a supply voltage of 1.2 V.Its in-band OIP3 result is at 14 dBm. 展开更多
关键词 low power DC offset programmable gain amplifier software defined radio
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A low power 2.4 GHz transceiver for ZigBee applications
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作者 刘威扬 陈晶晶 +1 位作者 王海永 吴南健 《Journal of Semiconductors》 EI CAS CSCD 2013年第8期110-119,共10页
This paper presents a low power 2.4 GHz transceiver for ZigBee applications.This transceiver adopts low power system architecture with a low-IF receiver and a direct-conversion transmitter.The receiver consists of a n... This paper presents a low power 2.4 GHz transceiver for ZigBee applications.This transceiver adopts low power system architecture with a low-IF receiver and a direct-conversion transmitter.The receiver consists of a new low noise amplifier(LNA) with a noise cancellation function,a new inverter-based variable gain complex filter (VGCF) for image rejection,a passive quadrature mixer,and a decibel linear programmable gain amplifier(PGA). The transmitter adopts a quadrature mixer and a class-B mode variable gain power amplifier(PA) to reduce power consumption.This transceiver is implemented in 0.18μm CMOS technology.The receiver achieves—95 dBm of sensitivity,28 dBc of image rejection,and -8 dBm of third-order input intercept point(IIP3).The transmitter can deliver a maximum of+3 dBm output power with PA efficiency of 30%.The whole chip area is less than 4.32 mm^2. It only consumes 12.63 mW in receiving mode and 14.22 mW in transmitting mode,respectively. 展开更多
关键词 low power noise cancellation quadrature mixer transceiver variable gain complex filter
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Theoretical design and analysis of high-gain over-moded microwave pulse compression system
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作者 Xiao-Yong Lei Zhi-Qiang Zhang +3 位作者 Dong-Ping Gao Wen-Xin Liu Ding Zhao Huai-Lin Gao 《Radiation Detection Technology and Methods》 CSCD 2024年第2期1208-1216,共9页
Purpose In the research of the microwave pulse compression,it was found that a new physical model has a high power gain for the rectangular TE_(1,0,20) resonant mode at 2.920 GHz in S-band than the traditional physica... Purpose In the research of the microwave pulse compression,it was found that a new physical model has a high power gain for the rectangular TE_(1,0,20) resonant mode at 2.920 GHz in S-band than the traditional physical model.In this report,the model structure,physical principle,simulation results,and theoretical analysis will be given in detail.Methods In the new physical model of microwave pulse compression system,(1)the technologies of the over-moded resonant cavity and over-sized output waveguide were used together first time for the rectangular TE_(1,0,20) resonant mode at 2.920 GHz in S-band,in order to improve the Q-value of the microwave resonant cavity and increase the power gain of the output pulse;(2)optimize the dimensions of the coupling window to get the maximum efficiency of the energy storage in the resonant cavity.Results From the latest research,it was shown that,in the optimal resonant state,(1)the power gain of the system can reach up to 276.97.Relative the traditional physical model,the power gain increased by 53.40%;(2)in the optimal resonant state,the energy storage efficiency of the over-moded system has also reached up to 88.91%.Relative to the traditional physical model,the efficiency increased by 23.33%;(3)another important result is that the power gain is very sensitive to the deviations of the resonant cavity length and output waveguide position from their optimal values.For example,the power gain will decrease by 61.45 or 67.17%,if the length deviation of the resonant cavity is−0.10 mm or+0.10 mm.It is very important to the theoretical and experimental studies.Conclusion It was shown that the new physical model of microwave pulse compression system has a higher power gain than the traditional physical model,by using the over-moded technology to the resonant cavity and output waveguide.Because of the universality of this high-gain over-moded physical model,the high-gain over-moded technology can be applied directly to X,Ku,and Ka bands. 展开更多
关键词 High power microwave Microwave pulse compression Over-moded cavity power gain
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Channel Capacity Estimation in TDMS-Based MIMO Measurements 被引量:2
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作者 姚元 郑剑锋 冯正和 《Tsinghua Science and Technology》 SCIE EI CAS 2011年第4期371-376,共6页
Time-division multiplexed switching (TDMS)-based multiple-input multiple-output (MIMO) channel sounders are widely used for wireless channel measurements due to their effective costs. However, meas- urement noise ... Time-division multiplexed switching (TDMS)-based multiple-input multiple-output (MIMO) channel sounders are widely used for wireless channel measurements due to their effective costs. However, meas- urement noise such as phase noise in the local oscillators as well as additive white Gaussian noise (AWGN) can result in significant errors in channel capacity estimates. This study analyzes the impact of phase noise and AWGN on channel capacity in TDMS-based MIMO measurements, with a channel capacity estimator presented that reduces the impact of noise on both the spatial multiplexing gain and on the power gain. Simulations demonstrate that the estimator consistently obtains the true capacity for various MIMO channel scenarios, even if only a limited number of observations are available. 展开更多
关键词 channel capacity multiple-input multiple-output (MIMO) systems phase noise spatial multiplex-ing gain power gain
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High performance 1 mm AlGaN/GaN HEMT based on SiC substrate 被引量:2
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作者 Weijun LUO Xiaojuan CHEN +5 位作者 Chengzhan LI Xinyu LIU Zhijing HE Ke WEI Xiaoxin LIANG Xiaoliang WANG 《Frontiers of Electrical and Electronic Engineering in China》 CSCD 2008年第1期120-122,共3页
This is our first report on the high performance 1 mm AlGaN/GaN high electron mobility transistor(HEMT)which was developed using home-made AlGaN/GaN epitaxy structures based on SiC substrate.Metal-organic chemical vap... This is our first report on the high performance 1 mm AlGaN/GaN high electron mobility transistor(HEMT)which was developed using home-made AlGaN/GaN epitaxy structures based on SiC substrate.Metal-organic chemical vapor deposition(MOCVD)was used to generate the epitaxy layers.Corresponding experiments show that the device has a gate length of 0.8 mm exhibiting drain current density of 1.16 A/mm,transconductance of 241 ms/mm,a gate-drain break-down voltage larger than 80 V,maximum current gain frequency of 20 GHz and maximum power gain frequency of 28 GHz.In addition,the power gain under the continues wave condition is 14.2 dB with a power density of 4.1 W/mm,while under the pulsed wave condition,power gain reaches 14.4 dB with power density at 5.2 W/mm.Furthermore,the two-port network impedance characteristics display great potential in microwave application. 展开更多
关键词 ALGAN/GAN high electron mobility transistor(HEMT) microwave power power gain
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RF study of a C-band barrel open cavity pulse compressor
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作者 束冠 赵风利 贺祥 《Chinese Physics C》 SCIE CAS CSCD 2015年第5期109-112,共4页
This paper focuses on the RF study of a C-band barrel open cavity (BOC) pulse compressor. The operating principle of BOC is presented and the technical specifications are determined. The main parts of BOC such as th... This paper focuses on the RF study of a C-band barrel open cavity (BOC) pulse compressor. The operating principle of BOC is presented and the technical specifications are determined. The main parts of BOC such as the cavity, the matching waveguide, the coupling slots and the tuning rings were numerically sinmlated by 3-D codes software HFSS and CST Microwave Studio (MWS). The "whispering gallery" mode TM6,1,1 with an unload Q of 100000 was chosen to oscillate in the cavity. An energy multiplication factor of 1.99 and a peak power gain of 6.34 was achieved theoretically. 展开更多
关键词 C-BAND BOC pulse compressor HFSS MWS energy multiplication factor peak power gain
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An extrinsic f_(max)>100 GHz InAlN/GaN HEMT with AlGaN back barrier
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作者 刘波 冯志红 +6 位作者 敦少博 张雄文 顾国栋 王元刚 徐鹏 何泽召 蔡树军 《Journal of Semiconductors》 EI CAS CSCD 2013年第4期46-49,共4页
We report the DC and RF performance of InAlN/GaN high-electron mobility transistors with AlGaN back barrier grown on SiC substrates. These presented results confirm the high performance that is reachable by InAlN-base... We report the DC and RF performance of InAlN/GaN high-electron mobility transistors with AlGaN back barrier grown on SiC substrates. These presented results confirm the high performance that is reachable by InAlN-based technology. The InAlN/GaN HEMT sample showed a high 2DEG mobility of 1550 cmE/(V-s) at a 2DEG density of 1.7 × 1013 cm-2. DC and RF measurements were performed on the unpassivated device with 0.2 μm "T" gate. The maximum drain current density at Vcs = 2 V is close to 1.05 A/mm in a reproducible way. The reduction in gate leakage current helps to increase the frequency performance of AlGaN back barrier devices. The power gain cut-off frequency of a transistor with an A1GaN back barrier is 105 GHz, which is much higher than that of the device without an A1GaN back barrier at the same gate length. These results indicate InAlN/GaN HEMT is a promising candidate for millimeter-wave application. 展开更多
关键词 AlGaN back barrier InA1N high-electron-mobility transistors power gain cutoff frequency
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Analysis and simulation of a coupled-cavity pulse compressor
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作者 肖欧正 赵风利 贺祥 《Chinese Physics C》 SCIE CAS CSCD 2012年第11期1132-1135,共4页
An equivalent circuit model is built for a coupled-resonator pulse compressor. Based on the circuit, the general second order differential equation is derived and converted into the first order equation to save comput... An equivalent circuit model is built for a coupled-resonator pulse compressor. Based on the circuit, the general second order differential equation is derived and converted into the first order equation to save computing time. In order to analyze the transient response and optimize parameters for the pulse compressor, we have developed a simulation code. In addition, we have also designed a three-cavity pulse compressor to get the maximum energy multiplication factor. The size of the cavities and coupling apertures is determined by HFSS. 展开更多
关键词 pulse compressor power gain energy multiplication factor
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Analog and radio-frequency performance analysis of silicon-nanotube MOSFETs
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作者 pramod kumar tiwari mukesh kumar +1 位作者 ramavathu sakru naik gopi krishna saramekala 《Journal of Semiconductors》 EI CAS CSCD 2016年第6期60-63,共4页
This work presents a comparative study of the influence of various parameters on the analog and RF properties of silicon-nanotube MOSFETs and nanowire-based gate-all-around(GAA) MOSFETs.The important analog and RF p... This work presents a comparative study of the influence of various parameters on the analog and RF properties of silicon-nanotube MOSFETs and nanowire-based gate-all-around(GAA) MOSFETs.The important analog and RF performance parameters of SiNT FETs and GAA MOSFETs,namely drain current(/d),transconductance to drain current ratio(g_m/I_d),I_(on)/I_(off),the cut-off frequency(f_T) and the maximum frequency of oscillation(/max) are evaluated with the help of Y- and H-parameters which are obtained from a 3-D device simulator,ATLAS^(TM).It is found that the silicon-nanotube MOSFETs have far more superior analog and RF characteristics(g_m/I_d,f_T and /max) compared to the nanowire-based gate-all-around GAA MOSFETs.The silicon-nanotube MOSFET shows an improvement of ~2.5 and 3 times in the case of f_T and /max values respectively compared with the nanowire-based gate-all-around(GAA) MOSFET. 展开更多
关键词 analog and RF SiNT MOSFETs GAA MOSFETs unity gain frequency unity power frequency
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