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Ultra-Low Power Small Size 5.8 GHz RF Transceiver Design for WiMAX/4G Applications 预览
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作者 Muhammad Yasir Faheem Shun’an Zhong +1 位作者 Abid Ali Minhas Muhammad Basit Azeem 《北京理工大学学报:英文版》 EI CAS 2019年第1期103-108,共6页
A state of the art ultra-low power small sized transceiver design has been proposed.This device consists of four blocks,including a frequency synthesizer(FS),a crystal oscillator(XO),transmitter and receiver attached ... A state of the art ultra-low power small sized transceiver design has been proposed.This device consists of four blocks,including a frequency synthesizer(FS),a crystal oscillator(XO),transmitter and receiver attached with an antenna.It has been seen that wireless information technology and systems have played a vital role in the transformation of society in different aspects of life.Mobile wireless communications including WiMAX/4G have attracted researchers and developers.WiMAX/4G applications need a transceiver that can be used in the worst channel conditions,but with low power consumption and low input voltage at the 5.8 GHz frequency.The proposed transceiver operates on 1.2 V.The operating frequency,noise figure(NF)and receiver gain are 5.8 GHz,4.0 dB and 90 dB respectively.It is a highly compatible transceiver with all the 4G technologies.Implementation details and results have revealed that the proposed transceiver is much more efficient than the previously proposed transceivers in literature. 展开更多
关键词 WORLDWIDE INTEROPERABILITY for MICROWAVE access frequency synthesizer(FS) power AMPLIFIER low noise AMPLIFIER
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Thulium-Doped Fiber Amplifier for Blue Light Signal Amplification 预览
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作者 Muhammad Hanif Ahmed Khan Khushik Chun Jiang 《中国通信:英文版》 SCIE CSCD 2019年第5期181-188,共8页
Fluoride-based thulium-doped visible light fiber amplifier(TmVLFA), which can be used to amplify the blue light signal for a visible light communication(VLC) system,is theoretically demonstrated for the first time acc... Fluoride-based thulium-doped visible light fiber amplifier(TmVLFA), which can be used to amplify the blue light signal for a visible light communication(VLC) system,is theoretically demonstrated for the first time according to the best of our knowledge. The transition rate equations and power propagation equations are solved to predict the dependence of the gain and noise figure on fiber parameters. The numerical results show that with the pump wavelength 1150 nm and pump power 800 mW, 2.75 m long thulium-doped fiber can amplify blue light(480 nm) signal up to 33.3 dB, and the noise figure is in the range from 3.0 to 3.5 dB. The model and numerical results encourage the use of fiber amplifier in VLC system for blue light amplification to extend the range of VLC. 展开更多
关键词 Tm-doped VISIBLE LIGHT FIBER AMPLIFIER VISIBLE LIGHT communication FIBER AMPLIFIER GAIN noise FIGURE
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Design of Power Amplifier for mm Wave 5G and Beyond 预览
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作者 LI Lianming SI Jiachen CHEN Linhui 《南京航空航天大学学报:英文版》 EI CSCD 2019年第4期579-588,共10页
With targets of cost reduction per bit and high energy efficiency,5G and beyond call for innovation in the mmWave transmitter architecture and the power amplifier(PA)circuit.To illustrate these points,this paper first... With targets of cost reduction per bit and high energy efficiency,5G and beyond call for innovation in the mmWave transmitter architecture and the power amplifier(PA)circuit.To illustrate these points,this paper firstly explains the benefits and design implications of the hybrid beamforming structure in terms of the mmWave spectrum characteristics,energy efficiency,data rate,communication capacity,coverage and implementation technology choices.Then after reviewing the techniques to improve the power amplifier(PA)output power and efficiency,the design considerations and test results of 60 GHz and 90 GHz mmWave PAs in bulk complementary metal oxide semiconductor(CMOS)process are shown. 展开更多
关键词 5G and beyond 6G BEAMFORMING complementary metal oxide semiconductor(CMOS) mmWave multiple input multiple output(MIMO) power amplifier TRANSMITTER
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宽带大功率放大器设计 预览
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作者 陈小兵 《数字技术与应用》 2019年第1期199-199,201共2页
本文介绍了一款输出功率大于200W的宽带功率放大器。该放大器的带宽跨越了5个倍频程,放大器使用推挽式场效应晶体管,采用负反馈技术、集总元件、微带混合宽带匹配电路实现,并加入自动功率控制(ALC)技术。通过ADS软件的仿真和反复调试,... 本文介绍了一款输出功率大于200W的宽带功率放大器。该放大器的带宽跨越了5个倍频程,放大器使用推挽式场效应晶体管,采用负反馈技术、集总元件、微带混合宽带匹配电路实现,并加入自动功率控制(ALC)技术。通过ADS软件的仿真和反复调试,得到理想的结果。 展开更多
关键词 放大器 宽带 大功率 负反馈 推挽
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New thermal optimization scheme of power module in solid-state amplifier 预览
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作者 Lie-Peng Sun Zhen-Yu Yuan +5 位作者 Cheng Zhang Xian-Bo Xu Jun-Gang Miao Jian-Hua Zhang Long-Bo Shi Yuan He 《核技术:英文版》 SCIE CAS CSCD 2019年第4期143-149,共7页
The new 1 kW power module for ADS project needs the optimization of cooling design including water flow and tunnel layout, and the water flow of three tons per hour was chosen to be a goal for a 20 kW power source. Ac... The new 1 kW power module for ADS project needs the optimization of cooling design including water flow and tunnel layout, and the water flow of three tons per hour was chosen to be a goal for a 20 kW power source. According to analysis from the insertion and integrated loss, about 24 modules were integrated into the rated power. Thus, every module has a cooling flow of 2.1 L/min for RF heat load and power supply loss, which is very hard to achieve if no special consideration and techniques. A new thermal simulation method was introduced for thermal analysis of cooling plate through CST multi-physics suite, especially for temperature of power LDMOS transistor. Some specific measures carried out for the higher heat transfer were also presented in this paper. 展开更多
关键词 RF system SOLID-STATE AMPLIFIER Power MODULE Heat TRANSFER COEFFICIENT
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Polarization dependence of gain and amplified spontaneous Brillouin scattering noise analysis for fiber Brillouin amplifier
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作者 穆宽林 商建明 +3 位作者 唐丽华 王正康 喻松 乔耀军 《中国物理B:英文版》 SCIE EI CAS CSCD 2019年第9期253-257,共5页
The polarization dependences of gain and amplified spontaneous Brillouin scattering(ABS) noise for fiber Brillouin amplifier(FBA) are analyzed through theories, simulations, and experiments.Modified vector propagation... The polarization dependences of gain and amplified spontaneous Brillouin scattering(ABS) noise for fiber Brillouin amplifier(FBA) are analyzed through theories, simulations, and experiments.Modified vector propagation equations for calculating the gain of the probe signal and the ABS noise are derived and analyzed in the Stokes spaces.In simulations and experiments, we prove that the gain of the probe signal and the ABS noise are strongly dependent on the relative state of polarization(SOP) of the pump and probe signals.The closer the relative SOP of the pump and probe signals is, the more obvious ABS noise suppression effect will be brought by increasing the power of the input probe signal. 展开更多
关键词 FIBER BRILLOUIN AMPLIFIER state of polarization stimulated BRILLOUIN SCATTERING SPONTANEOUS BRILLOUIN SCATTERING
有线电视网络中线路放大器的维护与维修研究 预览
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作者 徐军 《无线互联科技》 2019年第16期15-16,共2页
近年来,随着科学技术水平的逐渐发展,电视逐渐成为生活中的必须品。在科技不断进步的过程中,电视技术的发展和进步逐渐成熟,发挥着越来越重要的作用,市场上对电视的需求也在逐渐提升。有线数字电视在人们的生活中满足了生活娱乐、信息... 近年来,随着科学技术水平的逐渐发展,电视逐渐成为生活中的必须品。在科技不断进步的过程中,电视技术的发展和进步逐渐成熟,发挥着越来越重要的作用,市场上对电视的需求也在逐渐提升。有线数字电视在人们的生活中满足了生活娱乐、信息传媒等功能的需求,提升了人们追求精神文化的层次和水平。在电视系统进行使用和作业的过程中,随着系统的老化和损耗,以及自身使用阶段的不断缩小,有线电视网络会出现相应的问题,影响群众的使用效果。其中,故障频发的关键点在于线路放大器中的问题,针对有线电视线路放大器中出现的故障以及问题应当进行详细的维修和整合,帮助有线电视在使用的过程中更好地为消费者服务。文章将对于有线电视放大器中存在的故障提出相应的解决方式,进而延长有线电视的使用寿命,提升消费者的消费满足感。 展开更多
关键词 有线电视 网络 线路 放大器
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高重频高峰值功率窄线宽激光放大器 预览
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作者 颜凡江 杨策 +3 位作者 陈檬 桑思晗 李梦龙 蒙裴贝 《红外与激光工程》 EI CSCD 北大核心 2019年第2期102-106,共5页
高重复频率、高峰值功率、窄线宽的激光在激光雷达领域具有重要的应用价值。在对高重频窄线宽激光进行放大时,为了同时实现高放大倍率与高光束质量激光输出,在高重频、窄线宽被动调Q激光器作为种子源的前提下,设计了利用888 nm半导体激... 高重复频率、高峰值功率、窄线宽的激光在激光雷达领域具有重要的应用价值。在对高重频窄线宽激光进行放大时,为了同时实现高放大倍率与高光束质量激光输出,在高重频、窄线宽被动调Q激光器作为种子源的前提下,设计了利用888 nm半导体激光端面泵浦Nd:YVO4块状晶体实现高增益的一级放大,808 nm半导体激光侧面泵浦Nd:YVO4板条晶体实现低热透镜效应的二级放大的方案。在重复频率10 kHz时,获得了峰值功率5 MW,线宽154 pm,脉冲宽度0.6 ns,平均功率31.5 W,光束质量M2为1.98的激光输出。从而验证了将高放大倍率与高光束质量分别控制的放大器设计思路。 展开更多
关键词 放大器 高重复频率 高峰值功率 窄线宽 端面泵浦
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Doping radius effects on an erbium-doped fiber amplifier
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作者 Md.Ziaul Amin Khurram Karim Qureshi Md.Mahbub Hossain 《中国光学快报:英文版》 SCIE EI CAS CSCD 2019年第1期14-19,共6页
In an erbium-doped fiber amplifier(EDFA), erbium ions act as a three-level system. Therefore, much higher pump energy is required to achieve the population inversion in an erbium-doped fiber(EDF). This higher pump ene... In an erbium-doped fiber amplifier(EDFA), erbium ions act as a three-level system. Therefore, much higher pump energy is required to achieve the population inversion in an erbium-doped fiber(EDF). This higher pump energy requirement complicates the efficient design of an EDFA. However, efficient use of the pump power can improve the EDFA performance. The improved performance of an EDFA can be obtained by reducing the doping radius of the EDF. A smaller doping radius increases pump–dopant interactions and subsequently increases the pump–photon conversion efficiency. Decreasing the doping radius allows a larger proportion of dopant ions,which are concentrated near the core, to interact with the highest pump intensity. However, decreasing the doping radius beyond a certain limit will bring the dopant ions much closer and introduce detrimental ion–ion interaction effects. In this Letter, we show that an optimal doping radius in an EDF can provide the best gain performance. Moreover, we have simulated the well-known numerical aperture effects on EDFA gain performance to support our claim. 展开更多
关键词 DOPING RADIUS EFFECTS ERBIUM-DOPED FIBER AMPLIFIER
“项目”为核心的大学专业课程设计探析 预览
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作者 高博 《实验科学与技术》 2019年第3期76-80,共5页
以加州大学圣巴巴拉分校开设的——射频和微波电路设计课程为例,探讨了课程整体设计在以“项目”为核心的教学实践过程中的重要性。通过对该课程各环节内容的深入分析,讨论了在理论教学、作业、实验等环节如何具体围绕"项目”为核... 以加州大学圣巴巴拉分校开设的——射频和微波电路设计课程为例,探讨了课程整体设计在以“项目”为核心的教学实践过程中的重要性。通过对该课程各环节内容的深入分析,讨论了在理论教学、作业、实验等环节如何具体围绕"项目”为核心进行展开。该课程把一个难度较大的设计项目所涉及的众多知识点,巧妙地分散到了课程的各个环节,使学生能够由浅入深,水到渠成地完成最终设计。作为一个典型的"项目”为核心的教学案例,该课程可以为国内相关大学专业课程的教学改革提供参考和思路。 展开更多
关键词 大学专业课程 微波 矢量网络分析仪 放大器
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Saturation in wavelength-division multiplexing free-space optical communication systems
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作者 Jeremiah O. BANDELE Malcolm WOOLFSON Andrew J. PHILLIPS 《中国光电子学前沿:英文版》 EI CSCD 2019年第2期197-207,共11页
The performance of a wavelength-division multiplexing (WDM) free-space optical (FSO) commu-nication system in a turbulent atmosphere employing optical amplifiers to improve capacity is investigated, in the presence of... The performance of a wavelength-division multiplexing (WDM) free-space optical (FSO) commu-nication system in a turbulent atmosphere employing optical amplifiers to improve capacity is investigated, in the presence of amplified spontaneous emission noise, scintillation, beam spreading, atmospheric attenuation and interchannel crosstalk. Using on-off keying modulation, Monte Carlo simulation techniques are used to obtain the average bit error rate and system capability due to scintillation and the effect of introducing a power control algorithm (PCA) to the system is investigated. The PCA ensures that at any receiving instant, the same turbulence- free powers are received by all the receiving lenses. The performance of various WDM FSO communication system configurations such as non-amplified systems with an adaptive decision threshold (NOAADT), non- amplified systems with a non-adaptive decision threshold, fixed gain amplified systems with an adaptive decision threshold, fixed gain amplified systems with a non- adaptive decision threshold and saturated gain amplified systems with a non-adaptive decision threshold (SOA- NADT) are investigated. Results obtained show that the SOANADT is superior to the NOAADT and the PCA is only beneficial in amplified systems. 展开更多
关键词 WAVELENGTH-DIVISION multiplexing (WDM) FREE-SPACE OPTICAL (FSO) communication CROSSTALK OPTICAL amplifier (OA) gain SATURATION decision threshold
放大器下裝光机模块安裝姿态调整机构误差分析与补偿
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作者 张军 刘小波 谢志江 《机械设计与研究》 CSCD 北大核心 2019年第2期45-49,共5页
为了实现激光装置对放大器光机模块精密安装,设计了一种辅助安装的姿态调整机构。运用几何矢量法对该调整机构的位置正解和逆解进行了分析。通过矩阵法建立了模块安装姿态调整机构的位姿误差正逆解模型,并且验证了模型的正确性。通过改... 为了实现激光装置对放大器光机模块精密安装,设计了一种辅助安装的姿态调整机构。运用几何矢量法对该调整机构的位置正解和逆解进行了分析。通过矩阵法建立了模块安装姿态调整机构的位姿误差正逆解模型,并且验证了模型的正确性。通过改变不同的误差源对调整平台进行误差仿真分析,确定的不同误差源对平台运动精度的影响。采用直接误差补偿方法对姿态调整机构的运动误差进行补偿,经过两次补偿后,机构位置误差明显下降,误差值接近零值。证明了该方法是有效的,并成功将该方法运用于模块安装实验。 展开更多
关键词 放大器 光学模块 位置分析 误差模型 误差补偿
A novel method of optimizing latch comparators 预览
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作者 郑浩 Fan Xiangning 《高技术通讯:英文版》 CAS 2019年第3期255-261,共7页
A new method of improving speed of latch-type comparators with preamplifier is presented. It investigates the relationship of current and transistor scales which affect delay time(tp) in latch. It applies a mathematic... A new method of improving speed of latch-type comparators with preamplifier is presented. It investigates the relationship of current and transistor scales which affect delay time(tp) in latch. It applies a mathematical model to optimize latch design. A figure of merit indicates that ratio Ipmos/Inmos is 0.25 in latch leading to optimal delay time. In order to suppress offset of latch, the cross-coupled loading, adopted in telescope preamplifier, which enhances the gain, is well analyzed and designed. The chip is fabricated in 0.18 μm CMOS technology. The delay time of latch comparator is less than 400 ps @500 MHz. The offset of comparator is estimated through Monte Carlo simulation. And power consumption is only 144 W under 1.8 V power supply. Results of on wafer testing are presented at the end of the paper. The chip occupies an area of 0.66×0.55 mm^2 and drains current of 80 μA. 展开更多
关键词 cross-couple LATCH OFFSET TELESCOPE AMPLIFIER with cross-couple loading delay time
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Constant envelope FrFT OFDM: spectral and energy efficiency analysis 预览
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作者 DIDA Mussa Ally HUAN Hao +2 位作者 TAO Ran WANG Teng URYNBASSAROVA Didar 《系统工程与电子技术:英文版》 SCIE EI CSCD 2019年第3期467-473,共7页
Constant envelope with a fractional Fourier transformorthogonal frequency division multiplexing(CE-FrFT-OFDM)is a special case of a constant envelope OFDM(CE-OFDM),both being energy efficient wireless communication te... Constant envelope with a fractional Fourier transformorthogonal frequency division multiplexing(CE-FrFT-OFDM)is a special case of a constant envelope OFDM(CE-OFDM),both being energy efficient wireless communication techniques with a 0 dB peak to average power ratio(PAPR).However,with the proper selection of fractional order,the first technique has a high bit error rate(BER)performance in the frequency-time selective channels.This paper performs further analysis of CE-FrFT-OFDM by examining its spectral efficiency(SE)and energy efficiency(EE)and compare to the famous OFDM and FrFT-OFDM techniques.Analytical and comprehensive simulations conducted show that,the CE-FrFT-OFDM has five times the EE of OFDM and FrFT-OFDM systems with a slightly less SE.Increasing CE-FrFT-OFDM’s transmission power by increasing its amplitude to 1.7 increases its SE to match that of the OFDM and FrFT-OFDM systems while slightly reducing its EE by 20%to be four times that of OFDM and FrFTOFDM systems.OFDM and FrFT-OFDM’s amplitude fluctuations cause rapid changing output back-off(OBO)power requirements and further reduce power amplifier(PA)efficiency while CE-FrFTOFDM stable operational linear range makes it a better candidate and outperforms the other techniques when their OBO exceeds 1.7.Higher EE and low BER in time-frequency selective channel are attracting features for CE-FrFT-OFDM deployment in mobile devices. 展开更多
关键词 FRACTIONAL Fourier transform (FrFT) constant ENVELOPE SPECTRAL EFFICIENCY (SE) energy EFFICIENCY (EE) high power AMPLIFIER
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X波段10W功率合成放大器的设计与实现 预览
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作者 薄淑华 刘瑜现 任程 《无线电工程》 2019年第2期174-178,共5页
单个功放芯片输出功率的能力非常有限,通过研究平面功率合成网络的基本原理和设计方法,提出了一种基于平面功率合成技术的4路功率合成网络。测试结果表明,输出端口幅度一致性较好,输出端口的相位差小于4°,驻波小于1.5,两端口隔离... 单个功放芯片输出功率的能力非常有限,通过研究平面功率合成网络的基本原理和设计方法,提出了一种基于平面功率合成技术的4路功率合成网络。测试结果表明,输出端口幅度一致性较好,输出端口的相位差小于4°,驻波小于1.5,两端口隔离度大于15dB。设计并实现了工作在X波段、输出功率为10W的功率合成放大器,并通过实际测试得到放大器的输出功率大于10W,合成效率大于82%,与设计预期相符。 展开更多
关键词 平面功率合成 放大器 X波段
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大信号无水冷LD侧泵Nd∶YAG激光放大器 预览
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作者 邹吉跃 刘学胜 +6 位作者 徐爱东 王聪聪 闫岸如 赵明 杨松 刘友强 王智勇 《发光学报》 EI CAS CSCD 北大核心 2019年第7期885-890,共6页
为了获得高激光脉冲能量,设计了高能脉冲激光放大系统。对该放大系统的输出能量、脉冲宽度、能量稳定度、输出脉冲宽度等进行了研究。首先,进行四能级激光速率方程的分析递推出泵浦能量和储存能量、增益系数等的关系。接着,进行了激光... 为了获得高激光脉冲能量,设计了高能脉冲激光放大系统。对该放大系统的输出能量、脉冲宽度、能量稳定度、输出脉冲宽度等进行了研究。首先,进行四能级激光速率方程的分析递推出泵浦能量和储存能量、增益系数等的关系。接着,进行了激光放大器的系统设计,然后进行实验验证,最后,实验还进行了输出激光的性能测试。实验结果表明:在Nd∶YAG晶体棒尺寸为Φ8mm×100mm、Nd^3+的掺杂浓度为1.1%、泵浦功率最大24kW、重复频率为10Hz、泵浦电流为80A、泵浦脉宽为200μs的条件下,得到脉冲宽度10ns、最大脉冲能量1050mJ的脉冲激光,输出能量不稳定度<3%,通过刀口法测得水平和垂直方向光束质量M^2分别是3.9和4.8。满足了高能量、无水冷、稳定可靠等要求。 展开更多
关键词 LD侧面泵浦 放大器 高能量 无水冷
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High-power,Joule-class,temporally shaped multi-pass ring laser amplifier with two Nd:glass laser heads
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作者 Jiangtao Guo Jiangfeng Wang +5 位作者 Hui Wei Wenfa Huang Tingrui Huang Gang Xia Wei Fan Zunqi Lin 《高功率激光科学与工程:英文版》 CAS CSCD 2019年第1期60-67,共8页
A high-power.Joule-class,nanosecond temporally shaped multi-pass ring laser amplifier system with two neodymiumdoped phosphate glass(Nd:glass)laser heads is demonstrated.The laser amplifier system consists of three pa... A high-power.Joule-class,nanosecond temporally shaped multi-pass ring laser amplifier system with two neodymiumdoped phosphate glass(Nd:glass)laser heads is demonstrated.The laser amplifier system consists of three parts:an all-fiber structure seeder,a diode-pumped Nd:glass regenerative amplifier and a multi-pass ring amplifier,where the thermally induced depolarization of two laser heads is studied experimentally and theoretically.Following the injection of a square pulse with the pulse energy of 0.9 mJ and pulse width of 6 ns,a 0.969-J high-energy laser pulse at 1 Hz was generated,which had the ability to change the waveform arbitrarily,based on the all-fiber structure front end.The experimental results show that the proposed laser system is promising to be adopted in the preamplifier of high-power laser facilities. 展开更多
关键词 DEPOLARIZATION compensation LASER AMPLIFIER NEODYMIUM LASER ring LASER
微波功率放大器AM-PM转移系数测试方法研究 预览
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作者 李新雷 张进仓 +3 位作者 秦臻 高妍 林卓 张琳 《空间电子技术》 2019年第2期1-4,共4页
针对星载微波功率放大器AM-PM转移系数指标缺乏考核方法的问题,文章根据多载波非线性工作原理,通过输入放大器双载波信号、调整输入信号幅度变化、分析输出信号相位变化情况的测试方法,设计了通过矢网进行测试的方案。根据方案所搭建的... 针对星载微波功率放大器AM-PM转移系数指标缺乏考核方法的问题,文章根据多载波非线性工作原理,通过输入放大器双载波信号、调整输入信号幅度变化、分析输出信号相位变化情况的测试方法,设计了通过矢网进行测试的方案。根据方案所搭建的测试系统,完成了放大器的测试验证,测试精度可达0.1(deg/dB)。研究结果表明,文章给出的这种AM-PM转移系数测试方法,是有效、可行、实用的,为全面评估国产化星载微波功率放大器提供了具体的测试方法。 展开更多
关键词 放大器 AM-PM 转移系数 测试
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An enhanced digital predistortion algorithm based on polynomial model identification
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作者 Wanzhi MA Xin QUAN +4 位作者 Bo ZHAO Ying LIU Wensheng PAN Shihai SHAO Youxi TANG 《中国科学:信息科学(英文版)》 SCIE EI CSCD 2019年第2期156-164,共9页
To improve the accuracy of the nonlinear distortion correction for the radio frequency(RF)power amplifier(PA),it is necessary to precisely obtain the reverse function of the PA nonlinear model.However,the direct inver... To improve the accuracy of the nonlinear distortion correction for the radio frequency(RF)power amplifier(PA),it is necessary to precisely obtain the reverse function of the PA nonlinear model.However,the direct inversion of the PA nonlinear model involves solving a high-order univariate polynomial,which is difficult to apply in engineering.In this study,based on the envelope memory polynomial(EMP)model,the high-order terms of the nonlinear model are approximated by their previously calculated values through iterations and considered as known constants in the polynomial solution finding process,thereby resulting in a significant reduction in computational complexity.Compared with the direct inversion method,model of a 9 th-order nonlinear,the proposed method reduces the calculation time in the coordinated rotation digital computer(CORDIC)algorithm by at least 80%.The simulation results show that for a long-term evolution(LTE)downlink signal,the results obtained by the proposed simplified method agree well with those obtained by direct inversion method. 展开更多
关键词 digital PREDISTORTION power AMPLIFIER nonlinear DISTORTION MEMORY effects RADIO FREQUENCY
Wideband CMOS variable gain amplifier with decibel-linear gain control characteristic
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作者 Dun Shubo Li Bin +1 位作者 Shi Guochao Yang Geliang 《中国邮电高校学报:英文版》 EI CSCD 2019年第1期59-64,共6页
This paper presents a wideband variable gain amplifier(VGA) featuring a decibel-linear gain control characteristic. The decibel-linear gain control function is realized using two VGA cells and a control signal convert... This paper presents a wideband variable gain amplifier(VGA) featuring a decibel-linear gain control characteristic. The decibel-linear gain control function is realized using two VGA cells and a control signal converter. The bandwidth is extended by using cascode architecture together with active inductive load. To achieve small parasitic and low area,direct current(DC) coupling is adopted in the circuit while a DC offset cancellation(DCOC) circuit is introduced to cancel the DC offset. Fabricated in a 0.18 μm complementary metal oxide semiconductor(CMOS) process, the chip occupies an area of 0.53 mm×0.48 mm(including pads) and draws a total current of 9 mA from a 1.8 V supply. The measurement results show that the gain of the VGA varies from-40 dB to 18 dB while the control voltage varies from 0 to 1.8 V, resulting in a total gain control range of 58 dB. The 3 dB bandwidth of the VGA is larger than 260 MHz at maximum gain. 展开更多
关键词 variable GAIN amplifier exponential GAIN control DC OFFSET CANCELLATION WIDEBAND
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