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Design of a High Power Directional Coupler with High Directivity Used in the LHCD Launcher for EAST 被引量:1
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作者 张长虹 刘甫坤 +1 位作者 杨津甫 赵洪亮 《Plasma Science and Technology》 SCIE EI CAS CSCD 2009年第6期739-743,共5页
A high power waveguide directional coupler was designed to measure the transmitted power and reflected power in the 4.6 GHz LHCD (lower hybrid current drive) launcher for the EAST tokamak. The design principle of th... A high power waveguide directional coupler was designed to measure the transmitted power and reflected power in the 4.6 GHz LHCD (lower hybrid current drive) launcher for the EAST tokamak. The design principle of the coupler is assessed. Further analysis is performed by CST (computer simulating test) and Ansoft HFSS (high frequency structure simulator) software and the optimal structural parameter is obtained. In addition, finite element code ANSYS is used to determine the temperature distribution in the coupler conductively cooled by forced water. The test results of a directional coupler manufactured according to the design are close to what is expected. 展开更多
关键词 directional coupler directIVITY thermal analysis test
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Fabrication of Polymer Nonlinear Directional Coupler by Photo-bleaching 被引量:1
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作者 JIA Zhen hong (College of Information Science & Engineering, Xinjiang Univ., Urumqi 830046, CHN) 《Semiconductor Photonics and Technology》 CAS 2001年第4期217-220,246,共5页
The preparation of a nonlinear directional coupler in polymer PMMA/DR1 film by photobleaching is studied. We find it easier to obtain a required coupling length by controlling photo bleaching time than by controlling ... The preparation of a nonlinear directional coupler in polymer PMMA/DR1 film by photobleaching is studied. We find it easier to obtain a required coupling length by controlling photo bleaching time than by controlling the dimension of the coupler. The transmittance of each arm is measured when the pulse input light energy changes in our experiment. The experimental results show that the coupling length will change with the intensity of input light due to optical nonlinearities of the polymer PMMA/DR1 at 1 064 nm. 展开更多
关键词 Photo bleaching PMMA/DR1 polymer films Nonlinear directional coupler
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Nonideal effects in quantum field-effect directional coupler
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作者 谢月娥 颜晓红 陈元平 《Chinese Physics B》 SCIE EI CAS CSCD 2006年第10期2415-2421,共7页
The nonideal effects in a quantum field-effect directional coupler where two quantum wires are coupled through a finite potential barrier are studied by adopting the lattice Green function method. The results show tha... The nonideal effects in a quantum field-effect directional coupler where two quantum wires are coupled through a finite potential barrier are studied by adopting the lattice Green function method. The results show that the electron energy distribution, asymmetric geometry and finite temperature all have obvious influence on the electron transfer of the coupler. Only for the electrons with energies in a certain region, can the complete periodic transfer between two quantum wires take place. The conductance of these electrons as a function of the barrier length and potential height exhibits a fine periodic or quasi-periodic pattern. For the electrons with energies beyond the region, however, the complete periodic transfer does not hold any more since many irregular oscillations are superimposed on the conductance profile. In addition, the finite temperature and asymmetric geometry both can reduce the electron transfer efficiency. 展开更多
关键词 nonideal effects directional coupler Green function
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The Zero-gap Directional Coupler Integrated on SOI for 1.3μm Operation
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作者 赵策洲 《High Technology Letters》 EI CAS 1995年第2期51-52,共2页
SOI zero-gap directional couplers are studied by using large cross-section single-mode rib waveguide theory and dual-mode interference principle in silicon direct bonding SOI by back-polishing. And they are fabricated... SOI zero-gap directional couplers are studied by using large cross-section single-mode rib waveguide theory and dual-mode interference principle in silicon direct bonding SOI by back-polishing. And they are fabricated by using KOH anistropic etching. The insertion loss is measured to 4.81 dB, and the crosstalk is below —18.6 dB at a wavelength of 1.3μm. 展开更多
关键词 SOI INTEGRATED optics directional couplerS ANISOTROPIC ETCHING
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Design of a compact polarization beam splitter based on a deformed photonic crystal directional coupler
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作者 任刚 郑婉华 +3 位作者 王科 杜晓宇 邢名欣 陈良惠 《Chinese Physics B》 SCIE EI CAS CSCD 2008年第7期2553-2556,共4页
In this paper a compact polarization beam splitter based on a deformed photonic crystal directional coupler is designed and simulated. The transverse-electric (TE) guided mode and transverse-magnetic (TM) guided m... In this paper a compact polarization beam splitter based on a deformed photonic crystal directional coupler is designed and simulated. The transverse-electric (TE) guided mode and transverse-magnetic (TM) guided mode are split due to different guiding mechanisms. The effect of the shape deformation of the air holes on the coupler is studied. It discovered that the coupling strength of the coupled waveguldes is strongly enhanced by introducing elliptical airholes, which reduce the device length to less than 18.Sttm. A finite-difference tlme-domain simulation is performed to evaluate the performance of the device, and the extinction ratios for both TE and TM polarized light are higher than 20 dB. 展开更多
关键词 photonic crystal polarization beam splitter directional coupler
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IMPROVED MODE-MATCHING AND NETWORK ANALYSIS OF E-PLANE WAVEGUIDE BRANCH DIRECTIONAL COUPLERS
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作者 徐善驾 王峰 《Journal of Electronics(China)》 1995年第4期378-383,共6页
The E-plane waveguide branch directional couplers are analyzed by a method which combines the multimode network theory with rigorous mode-matching approach. The electromagnetic field components are expanded by the sup... The E-plane waveguide branch directional couplers are analyzed by a method which combines the multimode network theory with rigorous mode-matching approach. The electromagnetic field components are expanded by the superposition of LSEx modes rather than TE and TM modes in the mode-matching procedure. Meanwhile, the electromagnetic problem is transferred into the network problem through the mode-matching treatment. It is shown that the present method has the advantages of simplicity and less computation without affecting the accuracy of the calculation. 展开更多
关键词 E-PLANE WAVEGUIDE branch directional coupler MODE-MATCHING MULTIMODE network THEORY
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Analysis and Design of a 3 dB Tunable Lumped-Element Directional Coupler
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作者 Jun Wu Lu-Yu Wang 《Journal of Electronic Science and Technology》 CAS 2010年第2期160-163,共4页
An analysis of a 3 dB lumped-element directional coupler (LEDC) based on arbitrary terminal impedance is described numerically. To solve the conflicted requirement for broad bandwidth and small size in LEDC, a new s... An analysis of a 3 dB lumped-element directional coupler (LEDC) based on arbitrary terminal impedance is described numerically. To solve the conflicted requirement for broad bandwidth and small size in LEDC, a new structure of coupler is introduced, which can significantly improve bandwidth and whose size is only 3 cm×4 cm on the conditions of the frequency domain of 410 MHz to 490 MHz. The measure results are in good agreement with simulations despite the unexpected resistor loss. 展开更多
关键词 Index Terms--Terminal impedance BANDWIDTH lumped-element directional coupler (LEDC) varactor.
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Investigation on the multi-hole directional coupler for power measurement of the J-TEXT ECRH system
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作者 Wenting WENG Donghui XIA +3 位作者 Yizhe TIAN Xixuan CHEN Zhijiang WANG Yuan PAN 《Plasma Science and Technology》 SCIE EI CAS CSCD 2022年第6期196-205,共10页
Power measurement is necessary for an electron cyclotron resonance heating(ECRH)system.The directional coupler method has been put forward to monitor high-power microwave from gyrotrons in real time.A multi-hole direc... Power measurement is necessary for an electron cyclotron resonance heating(ECRH)system.The directional coupler method has been put forward to monitor high-power microwave from gyrotrons in real time.A multi-hole directional coupler has been designed and manufactured for the 105 GHz/500 kW ECRH system on the J-TEXT tokamak.During the design process,we established the relationships between hole parameters and coupling characteristics based on the multi-hole coupling method and small-hole coupling theory.High-power tests have been carried out.The results indicated the reasonability of the theoretical design and practicality of the fabricated directional coupler.Sources of test errors have been discussed in detail,and the influences of spurious modes on the directional couplers have been emphatically analyzed. 展开更多
关键词 directional couplers power measurement ECRH system
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MoM Analysis and Design of a Compact Coaxial-to-Microstrip Directional Coupler
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作者 Nadia Benabdallah Nasreddine Benahmed +1 位作者 Fethi Tarik Bendimerad Boumedienne Benyoucef 《Wireless Engineering and Technology》 2011年第2期45-52,共8页
In order to overcome the main drawbacks of coaxial, waveguide, and stripline couplers, the analysis and the design of a compact coaxial-to-microstrip directional coupler convenient for power and antenna control applic... In order to overcome the main drawbacks of coaxial, waveguide, and stripline couplers, the analysis and the design of a compact coaxial-to-microstrip directional coupler convenient for power and antenna control application, are presented using the method of moments (MoM) in two dimensions. This technique is adapted to study the complex configuration of the line’s system, which does not have a simple analytical solution. The modeling of this structure consists in analyzing the primary inductive and capacitive matrices ([L] and [C]). When these matrices are determined, it is possible to calculate the inductive and capacitive coupling coefficients (kL and kC) and estimate the resulting scattering parameters of the coupler using an adapted numerical model. The coupler can be integrated into a printed circuit board (PCB) and operates over 17 to 35 dB coupling coefficients and is always compensated. The compensation is achieved by the proper displacement of a tuning ground plane with respect to the edge of the PCB from 0.1 to 3.3 mm. As an application, we present the design of a compact coupler with 7.5 × 4.8 × 25.8 mm of size and having approximately 20 dB of coupling coefficient at 2 GHz and a minimum directivity of 23.3 dB in the frequency range [0.1 - 4] GHz. In order to check our numerical calculations by the MoM we made simulations in 3D by using CST MICROWAVE STUDIO software for the same geometrical and physical parameters of our designed coupler. The results obtained by the two numerical models (MoM and CST) show a good agreement of the frequency responses of the coaxial-to-microstrip directional coupler. The studied structure represents a great improvement for high power measurement systems, since it has broad-band, good directivity, and can be easily designed and fabricated. 展开更多
关键词 Coaxial-to-Microstrip coupler INHOMOGENEOUS Asymmetrical coupler A 20 dB COMPACT directional coupler Analysis and Design MOM Method CST MICROWAVE STUDIO Software
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一种宽频带复合天线设计
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作者 王亮 赵东贺 韩国栋 《计算机测量与控制》 2024年第3期273-279,共7页
针对多系统载体天线数量多的问题,提出了一种基于印刷振子结构的宽频带共口径复合天线设计方法;通过两种不同形式的印刷偶极子进行共口径设计:采用平面印刷偶极子结构完成宽带高增益线极化天线,通过宽带定向耦合器实现了天线和差方向图... 针对多系统载体天线数量多的问题,提出了一种基于印刷振子结构的宽频带共口径复合天线设计方法;通过两种不同形式的印刷偶极子进行共口径设计:采用平面印刷偶极子结构完成宽带高增益线极化天线,通过宽带定向耦合器实现了天线和差方向图辐射;采用十字印刷偶极子实现低增益天线的圆极化辐射;两种天线单元印刷在同一微波介质上,通过优化天线单元布局,相对位置关系和增加金属隔离环等措施,降低天线之间的相互影响,实现共口径复合天线性能满足工程应用要求;加工了天线样机,测试结果表明线极化天线在工作频带1.2~1.8 GHz范围内和差通道电压驻波比小于1.8,和通道增益大于13.5 dBi,方位差波束零值深度小于-25 dB,圆极化天线在工作频带1.2~1.8 GHz范围内电压驻波比小于1.6,增益大于6.5 dBi,轴比小于2.5 dB,与计算结果基本一致;复合天线可以满足多种无线通信系统的需求,减少了天线数量,有效节省载体平台空间,同时具有结构简单紧凑、剖面低、易于工程实现等特点,具有广阔的应用前景。 展开更多
关键词 复合天线 共口径 印刷偶极子 定向耦合器
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大功率超宽带高平坦度定向耦合器设计
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作者 张大伟 昌建军 +1 位作者 王慧丽 张峰平 《舰船电子对抗》 2024年第3期103-108,共6页
宽带大功率射频发射系统中的保护电路需要实时采集准确的射频信号。宽带大功率耦合器作为保护电路的关键器件,其耦合度的平坦度、方向度指标对保护电路采集射频信号的准确性起到关键影响。采用同轴结构的定向耦合器具备极小的插入损耗,... 宽带大功率射频发射系统中的保护电路需要实时采集准确的射频信号。宽带大功率耦合器作为保护电路的关键器件,其耦合度的平坦度、方向度指标对保护电路采集射频信号的准确性起到关键影响。采用同轴结构的定向耦合器具备极小的插入损耗,在接入射频通路后对通过功率影响极小。通过在拟合网络中采用传输线变压器谐振回路实现宽带高平坦度定向耦合。实测结果表明在80 MHz~1000 MHz频段的5000 W以上量级的大功率定向耦合器中,其耦合度为50 dB时,平坦度≤±0.3 dB,方向度>20 dB,耦合端口电压驻波比(VSWR)≤1.25,主通路插入损耗≤0.1 dB,主通路VSWR≤1.10。 展开更多
关键词 定向耦合器 耦合度 平坦度 保护电路 方向度 传输线变压器
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一种宽频带双圆极化微带天线阵列设计
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作者 王新 杨凯 +3 位作者 王飞 顾保国 李佳津 赵义 《计算机测量与控制》 2024年第7期308-314,共7页
为了支撑低轨卫星宽带数据下传需求,提出了一款宽频带双圆极化微带天线;采用微带天线作为基本辐射单元,基于层叠寄生贴片方式与加载空气腔方法展宽天线工作带宽并提高增益值,利用电容加载的三分支线定向耦合器对天线单元进行馈电进一步... 为了支撑低轨卫星宽带数据下传需求,提出了一款宽频带双圆极化微带天线;采用微带天线作为基本辐射单元,基于层叠寄生贴片方式与加载空气腔方法展宽天线工作带宽并提高增益值,利用电容加载的三分支线定向耦合器对天线单元进行馈电进一步展宽天线带宽,并实现双圆极化辐射特性;单元电性能仿真结果良好,阻抗相对带宽为28.2%,轴比相对带宽达14.5%,峰值增益达到5.6 dBi;基于辐射单元进行4×4阵列组合,所设计阵列天线阻抗带宽覆盖7.7~8.9 GHz,同一单元不同极化与不同单元间端口间隔离度均≥15 dB,轴比在通带内均≤3 dB,方向图仿真与测试结果吻合良好,验证了设计方案的正确性。 展开更多
关键词 宽频带 双圆极化 微带天线 电容加载 定向耦合器
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MPM功率监测方案研究及应用
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作者 张志伟 干媛 +1 位作者 蔡鹏锋 任卫宏 《真空电子技术》 2024年第5期97-100,共4页
微波功率模块(Microwave Power Module,MPM)是电真空发射机的发展方向之一,目前MPM饱和功率量级在百瓦量级。为保障系统工作稳定性和判断MPM的输出能效,需要MPM具有实时监测输出功率的能力。文章提出了一种在行波管输出端增加耦合口的... 微波功率模块(Microwave Power Module,MPM)是电真空发射机的发展方向之一,目前MPM饱和功率量级在百瓦量级。为保障系统工作稳定性和判断MPM的输出能效,需要MPM具有实时监测输出功率的能力。文章提出了一种在行波管输出端增加耦合口的方案来监测输出功率。相比传统通过定向耦合器测试功率的方案,该方案具有高效率、小型化、低成本、高可靠性等特点。 展开更多
关键词 MPM 定向耦合器 行波管 耦合检测
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VHF频段大功率定向功率合成器设计
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作者 张大伟 闫磊 《磁性材料及器件》 CAS 2024年第5期78-82,共5页
在100~350 MHz频段的1200 W以上量级的大功率功放模块,需要使用包括四路功率合成器和定向耦合器在内的多个器件。为实现大功率容量、小体积、宽频带和易于模块联调的设计目标,设计了VHF频段大功率定向功率合成器。通过采用反向平衡磁路... 在100~350 MHz频段的1200 W以上量级的大功率功放模块,需要使用包括四路功率合成器和定向耦合器在内的多个器件。为实现大功率容量、小体积、宽频带和易于模块联调的设计目标,设计了VHF频段大功率定向功率合成器。通过采用反向平衡磁路设计有效降低了磁心损耗,实现了大功率条件下的宽带小体积传输线变压器设计;通过采用带状线结构电路与传输线变压器合成电路一体集成的方式,实现了同时具备四路功率合成和正、反向定向耦合功能的宽带大功率定向功率合成器。功放模块联试显示,在100~350 MHz全频段可实现1200 W长时间稳定工作,占用体积比传统多个组合器件减小了60%以上。 展开更多
关键词 功率合成器 定向耦合器 传输线变压器 带状线
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基于亚波长光栅辅助定向耦合器的集成铌酸锂偏振分束器
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作者 陈力 周旭东 +2 位作者 袁明瑞 肖恢芙 田永辉 《人工晶体学报》 CAS 北大核心 2024年第3期465-471,共7页
绝缘体上铌酸锂(LNOI)是实现高速光子集成回路(PICs)的理想平台。通过充分利用铌酸锂(LN)的优势,LNOI平台能够实现高速电光和高效非线性光学集成器件。偏振分束器(PBS)作为分离和组合两种正交偏振光模式的关键无源器件之一,在实现片上... 绝缘体上铌酸锂(LNOI)是实现高速光子集成回路(PICs)的理想平台。通过充分利用铌酸锂(LN)的优势,LNOI平台能够实现高速电光和高效非线性光学集成器件。偏振分束器(PBS)作为分离和组合两种正交偏振光模式的关键无源器件之一,在实现片上偏振复用系统并提升光通信系统数据传输容量方面发挥着至关重要的作用。近年来,基于不同结构的PBS已经被成功实现,其中,基于亚波长光栅辅助定向耦合结构的PBS表现出优异的器件性能和紧凑的器件尺寸。本文基于氮化硅-铌酸锂异质集成的间接刻蚀方案,实现了一种亚波长光栅辅助定向耦合结构的高性能PBS。仿真结果表明,当波长在1500~1600 nm时,器件的偏振消光比均大于24.49 dB。实验数据进一步证实,当波长在1500~1580 nm时,器件偏振消光比均大于18.06 dB。 展开更多
关键词 薄膜铌酸锂集成光子学 氮化硅-铌酸锂 偏振调控器件 偏振分束器 亚波长光栅 定向耦合器
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BTM功放输出实时检测模块的设计与实现
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作者 周永健 吴庆鹏 +3 位作者 王东 王瑞 刘佳 梁迪 《铁道通信信号》 2024年第3期19-25,共7页
基于现场应答器传输单元故障检测需求,为实现对功放输出异常、电缆短路、电缆断路、运行正常4种不同状态的检测,在现有BTM功放单元上研发检测模块。根据传输线理论和矢量网络法,采用定向耦合器提取功放输出信号耦合电压和反射电压,经计... 基于现场应答器传输单元故障检测需求,为实现对功放输出异常、电缆短路、电缆断路、运行正常4种不同状态的检测,在现有BTM功放单元上研发检测模块。根据传输线理论和矢量网络法,采用定向耦合器提取功放输出信号耦合电压和反射电压,经计算获得不同特征状态判定参数;获取实验室和现场不同测量条件下不同特征状态的参数分布范围,采用阻抗作为判定参数时,因特征状态参数区间存在部分重叠,以不误报、不漏报为原则,最终选取耦合电压和反射电压作为判定参数。经过多次动态测试验证,该模块可为现场BTM设备功放输出状态的实时检测提供可靠依据,提高BTM设备故障排查自动化水平和效率。 展开更多
关键词 应答器传输单元 功放 检测模块 定向耦合器 矢量网络法 阻抗
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Switching Dynamic Analysis for Twin-Core Fibre Coupler Using Supermode Theory
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作者 罗爱平 徐文成 +1 位作者 陈伟成 崔虎 《Chinese Physics Letters》 SCIE CAS CSCD 2006年第2期381-384,共4页
Characteristics of optical switching in a twin-core fibre coupler are numerically analysed under short pulse input by using supermode theory. The dynamic nonlinear coupled superlnode equations are derived, The numeric... Characteristics of optical switching in a twin-core fibre coupler are numerically analysed under short pulse input by using supermode theory. The dynamic nonlinear coupled superlnode equations are derived, The numerical results show that the input pulse width determines the power transfer and the pulse temporal profile in the output ports. The optimal switching characteristics can be obtained by selecting an appropriate initial pulse width. In addition, the switching characteristic curves are insensitive to the input pulse shape for either fundamental soliton pulse or Gaussian pulse input, but sensitive to pulse sharpness. A reduced switching power and a sharper switching transition can be obtained by using the sharp super-Gaussian pulse. 展开更多
关键词 NONLINEAR directional coupler INTERMODAL DISPERSION PROPAGATION
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一种S频段反射型可调模拟移相器的设计
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作者 赵来定 万梦军 +2 位作者 张更新 田旺 廉佳鹏 《微电子学》 CAS 北大核心 2023年第2期241-246,共6页
设计了一种应用于S频段卫星通信相控阵系统的反射型可调模拟移相器。该移相器利用三分支线定向耦合器扩展了带宽,改善了工作频段内驻波;采用传输线和变容二极管构成的L型反射负载扩大了相移量。测试结果表明,在上行频段1.98~2.01 GHz内... 设计了一种应用于S频段卫星通信相控阵系统的反射型可调模拟移相器。该移相器利用三分支线定向耦合器扩展了带宽,改善了工作频段内驻波;采用传输线和变容二极管构成的L型反射负载扩大了相移量。测试结果表明,在上行频段1.98~2.01 GHz内,相移量达到191°±1°,在下行频段2.17~2.2 GHz内,相移量达到186°±0.1°;插入损耗优于3.3 dB且插入损耗波动小于1 dB,回波损耗在整个电压调谐范围内均大于20 dB。该移相器结构简单、便于调节且价格低廉,在卫星通信领域有一定的应用价值。 展开更多
关键词 S频段 反射型移相器 三分支线定向耦合器 变容二极管
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基于多物理场仿真的超宽带大功率电桥设计
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作者 陈晓青 朱建彬 +1 位作者 成爱强 顾黎明 《固体电子学研究与进展》 CAS 北大核心 2023年第2期175-180,共6页
为满足大功率组件中功率合成的需求,设计加工了一款表贴式超宽带大功率电桥。该电桥采用蛇形带状线,优选低损耗、高热导率的介质板(SJ9350H),降低介质厚度等方法,极大地减小了器件尺寸。同时采用多节定向耦合器结构,利用各节耦合器反射... 为满足大功率组件中功率合成的需求,设计加工了一款表贴式超宽带大功率电桥。该电桥采用蛇形带状线,优选低损耗、高热导率的介质板(SJ9350H),降低介质厚度等方法,极大地减小了器件尺寸。同时采用多节定向耦合器结构,利用各节耦合器反射波彼此抵消原理,实现了超宽带特性。在电桥端口处进行半开帽处理,可将内部热量通过介质传导和空气对流方式散发出去,提升了电桥的耐功率能力。文中还采用COMSOL多物理场软件对大功率工作状态下电桥的电场与温度进行了电热联合仿真。测试结果表明,该表贴式超宽带大功率电桥的工作频带为0.2~1.0 GHz,电压驻波比小于1.3,插损小于0.6 dB,平均抗烧毁功率大于350 W。 展开更多
关键词 大功率 超宽带 多节定向耦合器 电热联合仿真
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Optimization Design and Application of S-Band 3dB Directional Coupler
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作者 张敬如 赵风利 裴士伦 《Chinese Physics C》 SCIE CAS CSCD 北大核心 2008年第z1期172-174,共3页
The application of the 3dB directional coupler is very extensive,such as the phase shifter,the attenuator and the RF pulse compressor etc.The performance of the 3dB directional coupler is very important for these comp... The application of the 3dB directional coupler is very extensive,such as the phase shifter,the attenuator and the RF pulse compressor etc.The performance of the 3dB directional coupler is very important for these components. Optimization design has been done using the HFSS code.The new phase shifter prototype using the new optimization results has been tested.The tested results are in agreement with the measured ones. 展开更多
关键词 3dB directional coupler phase shifter VSWR BALANCE ISOLATOR
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