共查询到19条相似文献,搜索用时 218 毫秒
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Ka波段五位分布式MEMS传输线移相器设计 总被引:1,自引:1,他引:0
通过在共面波导上周期性地加载分布电容,外加驱动电压改变电容值,实现分布式MEMS移相器。首先给出了5位分布式MEMS移相器的总体结构图,分析了理论参数的设计方法。再采用HFSS建立单个微桥的三维电磁仿真模型,利用仿真得到的S参数拟合微桥的up态和down态电容值并与理论设计电容值对比,确定MEMS桥精确的结构参数。最后采用ADS建立分布式MEMS移相器整体的微波等效电路,仿真得出移相器的性能指标参数。仿真结果表明移相器在35GHz时移相精度小于0.6°,移相器的插入损耗小于0.3dB,回波损耗大于25dB。 相似文献
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报道了一种Ka波段实时延MEMS移相器芯片。该移相器基于开关线式移相器设计原理,集成了4个MEMS三端口直接接触式毫米波开关单元,使用共面波导(CPW)传输线,利用阶梯阻抗的方式实现传输线拐角和CPW空气桥结构的传输线阻抗匹配。芯片采用RF MEMS表面牺牲层工艺制作在400μm厚的高阻硅衬底上,面积为1.4 mm×2.8 mm。测试显示,在34~36 GHz频率范围内,相移误差3.2°,插入损耗2 dB,反射损耗小于-15 dB。 相似文献
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在蓝宝石基片上使用Ba_xSr_(1-x)TiO_3(BST)铁电薄膜电容作为可调元件制作出一种五阶梳状线可调带通滤波器。通过对BST平行板电容的材料特性(介电常数、损耗和可调率)的提取,其中40 V偏压下的可调率为43.1%,将这些特性运用于可调滤波器的制作。初步的实验结果分析表明,在20V直流偏置电压作用下,滤波器的中心频率从1.19GHz变化到1.31GHz(可调率为10.1%),带内插入损耗为13.5~13.7dB,回波损耗低于12dB。 相似文献
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Qingduan Meng Xueqiang Zhang Fei Li Jiandong Huang Xiaohong Zhu Dongning Zheng Bolin Cheng Qiang Luo Changzhi Gu Yusheng He 《Microwave and Wireless Components Letters, IEEE》2006,16(6):345-347
We present a distributed phase shifter with an equal ripple return loss at its operation frequency range. The phase shifter is based on a periodic structure and consists of a coplanar waveguide (CPW) line periodically loaded with voltage-variable barium strontium titanate (BST) interdigitated capacitors. Measurements show that its return loss is better than -15dB at frequencies from direct current to 16GHz, and at 9.4GHz, its phase shift is 41/spl deg/ under 120-V applied bias voltage. 相似文献
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通过在共面波导传输线上周期性地加载分布电容,外加驱动电压改变电容值,实现分布式MEMS传输线移相器。从三个方面优化了五位分布式MEMS传输线移相器的设计:一是分别设计了11.25°和22.5°两种微桥,单元在Ka波段的插入损耗均大于-0.8 dB,回波损耗均小于-15 dB,相移精度小于0.4°,新的五位移相器以2种单元、19个微桥的结构替代了传统单一单元、31个微桥的结构,可减少微桥的总数;二是CPW传输线采用折叠布局,通过共用部分地线,移相器平面尺寸减小至1.81 mm×3.84 mm,相比传统五位分布式移相器,面积减小了56%,实现了器件的小型化;三是设计了一种新型的直流偏置结构,结构简单、工艺容易实现。 相似文献
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Seung Eon Moon Han Cheol Ryu Min Hwan Kwak Young Tae Kim Su‐Jae Lee Kwang‐Yong Kang 《ETRI Journal》2005,27(6):677-684
A phased array antenna was fabricated using four‐element ferroelectric phase shifters with a coplanar waveguide (CPW) transmission line structure based on a Ba0.6Sr0.4TiO3(BST)/MgO structure. Epitaxial BST films were deposited on MgO (001) substrates by pulsed laser deposition. To attain the large differential phase shift and small losses for a ferroelectric CPW phase shifter, an impedance‐matching‐part adding technique between the effective transmission line and connecting cable was used. The return loss and insertion loss for this technique‐adapted BST CPW device were improved with respect to those for a normal BST CPW device. For an X‐band phased array antenna system consisting of ferroelectric BST CPW phase shifters, power divider, dc block, patch antenna, and programmed dc power, the steering beam could be tilted by 15° in either direction. 相似文献
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Dongsu Kim Yoonsu Choi Ahn M. Allen M.G. Stevenson Kenney J. Marry P. 《Microwave and Wireless Components Letters, IEEE》2003,13(10):434-436
Continuously variable ferroelectric (BST on sapphire) phase shifters based on all-pass networks are presented. An all-pass network phase shifter consists of only lumped LC elements, and thus the total size of the phase shifter is kept to less than 2.2 mm /spl times/ 2.6 mm at 2.4 GHz. The tunability (C/sub max//C/sub min/) of a BST interdigital capacitor is over 2.9 with a bias voltage of 140 V. The phase shifter provides more than 121/spl deg/ phase shift with the maximum insertion loss of 1.8 dB and the worst case return loss of 12.5 dB from 2.4 GHz to 2.5 GHz. By cascading two identical phase shifters, more than 255/spl deg/ phase shift is obtained with the maximum insertion loss of 3.75 dB. The loss figure-of-merit of both the single- and double-section phase shifters is over 65/spl deg//dB from 2.4 GHz to 2.5 GHz. 相似文献
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Haijun Tang Chuanren Yang Jihua Zhang Hongwei Chen An Yu Wei He Yu Liao 《Journal of Infrared, Millimeter and Terahertz Waves》2010,31(7):852-857
A kind of distributed coplanar waveguide (CPW) phase shifter based on LaAlO3 substrates is designed and fabricated in this paper. The Ba0.4Sr0.6TiO3 (BST) thin films employed in the circuits are deposited by RF magnetron sputtering, and then annealed at 800°C for 30 min
in air. The dielectric tunability, loss tangent of the BST films are respectively 43.7% and 0.017 at 100 kHz and 30 V, the
leakage current is approximately 1 × 10−9A/cm2 at zero bias voltage. The CPW phase-shifter designed is subsequently fabricated in order to obtain a 360° phase shift at
30 GHz with a moderate bias voltage. The maximal phase shift is 372° at 22.5 GHz with a bias voltage of 40 V. 相似文献
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Hong-Teuk Kim Dae-Hyun Kim Youngwoo Kwon Kwang-Seok Seo 《Electronics letters》2002,38(8):374-376
A reflection-type coplanar waveguide (CPW) phase shifter fabricated using a standard monolithic microwave integrated circuit (MMIC) process is presented. Air-gap overlay CPW couplers were employed for wideband 3 dB coupling and low loss at millimetre wave. The two-stage cascaded analogue phase shifter showed insertion losses of 6.9 ± 1.6 dB, return losses > 10 dB, and maximum rms phase error of +5.5° for the relative phase shift from -20° to 135°, over a wideband 27 to 47 GHz 相似文献
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面向现代通信及相控阵雷达领域的需求,设计了一种移相间隔为22.5°的Ka波段4位开关线型射频MEMS移相器。主要对实现移相功能的四个移相单元进行了设计,采用台阶补偿技术优化移相单元上下通路分工选通,以提供最佳的阻抗匹配;采用直角转角结构,设计了可提高CPW直角性能的延迟线,并对应用该延迟线的4位开关线型移相器进行了总体设计。用HFSS进行建模仿真,结果表明,在0~40 GHz工作频段内,16个状态的插入损耗均小于2.15 dB,回波损耗均大于19.18 dB,驻波比均小于1.25,在40 GHz频点处的相移误差在1.57°以内,整体尺寸为10 mm2。 相似文献
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Guan-Leng Tan Mihailovich R.E. Hacker J.B. DeNatale J.F. Rebeiz G.M. 《Microwave and Wireless Components Letters, IEEE》2003,13(4):146-148
The design and performance of a compact low-loss X-band true-time-delay (TTD) MEMS phase shifter fabricated on 8-mil GaAs substrate is described. A semi-lumped approach using microstrip transmission lines and metal-insulator-metal (MIM) capacitors is employed for the delay lines in order to both reduce circuit size as well as avoid the high insertion loss found in typical miniaturized designs. The 2-bit phase shifter achieved an average insertion loss of -0.70 dB at 9.45 GHz, and an associated phase accuracy of /spl plusmn/1.3/spl deg/. It occupies an area of only 5 mm/sup 2/, which is 44% the area of the smallest known X-band MEMS phase shifter . The phase shifter operates over 6-14 GHz with a return loss of better than -14 dB. 相似文献