共查询到20条相似文献,搜索用时 46 毫秒
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CDMA系统用高温超导滤波器的设计 总被引:1,自引:0,他引:1
本文根据CDMA(Code Division Multiple Access)移动通信系统的要求,采用Sapphire基片上的双面YBCO高温超导薄膜设计和制作了中心频率为830MHz,相对带宽为1.2%的16节高温超导滤波器,其谐振器采用了折叠型结构,能够显著地减小所用基片的尺寸.在68K的测试温度下实验结果与设计结果很好的吻合,带边陡峭度达到了50dB/MHz,带外抑制超过80dB,带内插损小于0.27dB,而尺寸限制在两英寸内. 相似文献
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研制了一种高选择性的24阶切比雪夫(Chebyshev)型高温超导带通滤波器,其中心频率为1748MHz、带宽为75MHz,适用于GSM移动通讯基站系统.此滤波器是在直径为3英寸、厚度为0.43毫米的铝酸镧双面超导薄膜上制作的.滤波器的计算机仿真是用Sonnet软件完成的.在滤波器设计中,提出了一种结构新颖的谐振器.在77K时,它具有很高的品质因子,约为30000.测试结果表明,该滤波器具有很好的选择性,带边陡度为17dB/MHz,带外抑制优于-90dB. 相似文献
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一种结构紧凑的高温超导窄带带通滤波器 总被引:1,自引:0,他引:1
研制了一种结构紧凑的高温超导窄带滤波器.该滤波器中心频率为,是在以0.5mm厚的LaAO3(εr≈24)为衬底的YBCO超导薄膜上制作的.测试结果显示该滤波器具有比较好的性能,其插入损耗<0.3dB,反射损耗<-16dB,相对带宽<9‰, 带边陡度>9dB/MHz, 中心频率误差<0.05%.滤波器设计中,利用特殊技术成功地改善了过渡带上的零点特性,为今后研制新型的结构紧凑的滤波器开拓了思路. 相似文献
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根据高温超导薄膜的特点,详细讨论了制备高温超导滤波器的光刻技术及在制备的各环节中需注意的问题,实验结果表明:此种方法提高了制备的成功率。 相似文献
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Sung Soo Choi Dong Chul Park 《International Journal of Infrared and Millimeter Waves》2007,28(11):961-967
A new compact millimeter-wave dual-mode ring resonator bandpass filter is proposed. This filter has a 15% bandwidth at 58 GHz
with 3.4 dB insertion loss. Input/output lines and ring resonator are directly connected to obtain tight coupling, and an
open-end stub is inserted for dual-mode operation. This filter is fabricated on a GaAs wafer by using MEMS technology and
can be applied for the millimeter- wave SoC. 相似文献
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波分复用薄膜带通滤光片的中心波长温度稳定性 总被引:8,自引:3,他引:5
讨论了影响波分复用薄膜滤光片中心波长漂移的因素 ,着重分析了滤光片的温度稳定性。根据实验结果 ,借助于高桥模型 ,分析计算了滤光片的折射率温度系数、线膨胀系数和泊松比以及它们对温度漂移的影响。得到了Ta2 O5/SiO2 滤光片薄膜的折射率温度系数、线膨胀系数、泊松比分别为 1× 10 -5℃-1,5× 10 -7℃-1和 0 12 ,指出了这三个参量是影响温度稳定性最重要的因素 ,特别是薄膜的折射率温度系数。对特定的基板热膨胀系数 ,通过调节滤光片的干涉级次和间隔层材料 ,可望得到零温度漂移的稳定滤光片。 相似文献
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Narendra Chauhan Ankush Mittal M. V. Kartikeyan 《International Journal of Infrared and Millimeter Waves》2008,29(6):558-569
In this paper, a hybrid soft computing method for designing specific microstrip antenna is presented. Evolutionary algorithm
such as genetic algorithm (GA) is one of the promising ways of finding global optimum solution from a multivariate nonlinear
feature space. Being a stochastic iterative algorithm, it requires much computation power when the function to be optimized
is complex and time consuming. Various meta-modelling techniques such as neural network, response surface methods, kriging,
etc. can be used to model the process under optimization in order to reduce the computational expenses. In this paper, we investigate
one such technique – support vector regression (SVR) – to model the complex analytical process. The model, thus obtained, is used for optimization using genetic algorithms. This
approach is demonstrated for the design of circular polarized microstrip antenna at 2.6 GHz band. The results of SVR model
are compared with other meta-models generated with neural network and response surface methodology. 相似文献
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高温超导电力电缆开发及应用近况 总被引:2,自引:0,他引:2
文中主要介绍了主要工业化国家中的美国、德国、日本和我国在高温超导电力电缆研制和应用计划的一些最新进展,表明HTS电缆商业应用技术已经接近成熟。最后对我国HTS电缆的研究发展提出了建议 相似文献
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Haiyan Chen 《International Journal of Infrared and Millimeter Waves》2005,26(8):1141-1150
This paper addresses in the design of thin film filter for IR broadband integrated photonic amplifiers. A cascaded multilayer medium thin film filter structure is presented. This proposed filter consists of some different filtering unit cells with different central wavelength and bandwidth, and each cell can suppress certain peak gain at a specific wavelength. The intrinsical gain spectrum of amplifier is obtained by solving a set of rate and power propagation equations with finite difference time-domain(FDTD)-based overlapping integral-Runge Kutter(RK) method. The effect of transmittance spectrum of the proposed cascaded multilayer medium thin film filter on flattening gain is discussed. The transmission function of the cascaded multilayer medium thin film filter is obtained. Finally, a real device is fabricated, it is shown that the design is valid. 相似文献
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Giovanni Angiulli Mario Versaci 《International Journal of Infrared and Millimeter Waves》2002,23(10):1513-1520
A fast method for the design of circular and equilateral triangular microstrip antennas, based on a Neuro-Fuzzy Network, is presented. Numerical results obtained by using this technique agree quite well with the Moment Method results. The proposed technique can be fruitfully used in microwave and millimeter wave CAD applications. 相似文献