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1.
倪国旗  韩非凡  张昱凯 《电讯技术》2016,56(12):1381-1386
采用了介质埋藏的形式将平面蝶形天线埋藏于介质中,并设计了渐变的平面微带巴伦给平面蝶形天线馈电,实现了不平衡到平衡的转换;还设计了三角形微带巴伦和微带传输线一起的结构形式,进行阻抗匹配。使用电磁仿真软件Ansoft HFSS对该天线进行了优化设计和仿真实验,与制作的实物天线性能进行对比。仿真和实测结果表明,该天线S11≤-10 dB仿真的相对带宽达到88.7%而实测的相对带宽为79.3%,具有超宽带特性;在工作频率处,仿真增益为6.9 dB,实测增益为5.8 dB。该天线满足某工程项目的需要,可作为探地雷达系统的收发天线。  相似文献   

2.
本文设计一种共面波导馈电的超宽带天线(UWB),其阻抗带宽达到341%。所设计的天线印刷在尺寸为28×21×1.6mm3,介电常数为2.65的聚四氟乙烯介质基板上。并利用电磁仿真软件HFSS对影响天线性能的主要物理参数进行仿真、分析和优化,得到天线的理想尺寸。最后,对优化的超宽带天线进行制作,测试。实验结果表明,该天线比传统微带贴 片天线性能有了较大的提高,从而证明利用共面波导馈电的超宽带天线设计方法,能够实现兼容多种通信系统的可行性和有效性。  相似文献   

3.
分析了平面螺旋天线的研究方法,并设计了工作于2~12 GHz 的新颖的超宽带平面等角螺旋天线,由天线的宽带特性指标和平衡结构特性,天线两臂的辐射部分设计了一种带环状贴片的天线辐射结构,使圆极化轴比带内小于3 dB,天线馈电部分设计了一种阻抗为指数渐变和梯形渐变相结合的双线形式微带线宽带巴伦,并可采用50 W 同轴探针馈电,使带内反射系数小于-10 dB。测试结果表明,馈电的微带巴伦和天线带环状的结构形式都表现出良好的宽频带和圆极化特性。  相似文献   

4.
提出了一种新颖的小型共面波导馈电超宽带(UWB)天线.该天线是基于开环谐振器(SRRs)的结构变形而来,设计时共采用了三对成等差数列的开环谐振结构作为天线的辐射面,同时为了获得较好的超宽带频率特性,馈电微带线采用了渐变微带线共面波导馈电结构.通过数值仿真计算获得了优化后的天线几何尺寸,并且加工制作了一副天线,对天线的回波损耗特性、方向图以及增益都进行了测试.测试结果显示该天线具有良好的超宽带特性和较高的增益.  相似文献   

5.
设计了一种新型的微带转共面带状线(coplanarStripLine以下简称CPS)的巴伦结构。它可以应用于多种常用的介质板上,具有结构紧凑、超宽带、低损耗的特点。制作了一个两端为500微带线的背靠背电路,测试得插入损耗(S21)〉-1dB、回波损耗(S11)〈-15dB的带宽为2.7GHz~7.3GHz,S21〉-4dB、S11〈-10dB的带宽为1.4GHz~15.6GHz。  相似文献   

6.
提出了一种工作频率为914MHz的印刷偶极子天线。为了使天线获得宽带特性和平衡馈电,采用了微带线到共面带状线的巴伦馈电。仿真表明天线在830MHz~1030MHz左右范围内,回波损耗低于-10dB,相对带宽可达22%。在中心工作频点上,该天线具有良好的回波损耗,可达-50dB。且结构简单,易于制作和集成,可用于相关的无线数据采集系统中。  相似文献   

7.
基于微带-共面波导过渡和“蝶形”缺陷地结构,研究微带传输线的带线与金属地之间的不平衡交叉过渡,将其应用于一种新型的超宽带1 bit移相器设计.在此基础上,设计一种超宽带同相/反相输出可切换射频网络,并进行实验验证.实验结果表明,在4.6~8.6 GHz频带内,该网络输出两端口的幅度差小于0.25 dB,插入损耗小于3 dB,相位差在-1°~8°(同相输出)和172°~182°(反相输出)以内,两端口隔离度优于22 dB,达到了良好效果.  相似文献   

8.
《电子元件与材料》2021,40(1):99-104
提出了一款共面波导馈电的超宽带双陷波天线。该天线主要由梯形共面地、微带馈线和圆形辐射体三部分构成。其中,梯形共面地使天线实现超宽带,圆形辐射贴片上的倒L形槽和弧形槽使天线实现陷波特性。使用Ansoft HFSS软件对所设计天线进行仿真实验,然后加工成实物天线并进行测试。结果表明:天线回波损耗及辐射方向图的实测结果与仿真结果基本吻合,在3.0~10.9 GHz频段内,除陷波频段3.3~3.6 GHz和5.15~5.825 GHz外,天线的回波损耗均在-10 dB以下,相应工作频段内有较好的辐射方向图。因此,所设计的天线性能满足超宽带通信系统应用要求。  相似文献   

9.
本文设计了微带馈电和共面波导馈电的平面宽槽超宽带天线。采用阶梯式过渡微带拓宽了天线的阻抗带宽,分析了开槽大小对天线驻波的影响。槽和馈电单元都采用了由椭圆和矩形构成的混合结构。这两种天线在实现小型化的同时,满足了FCC规定的超宽带标准。文章的最后部分采用寄生条带和贴片开槽的方法,实现了天线的双阻带特性。  相似文献   

10.
共面波导馈电超宽带天线研究   总被引:1,自引:1,他引:0  
设计了一种刻蚀在单层覆铜介质基板上的共面波导馈电超宽带天线。所用介质基板由相对介电常数为2.65的聚四氟乙烯制成,尺寸为35.0 mm×35.0 mm×1.6 mm。利用仿真软件HFSS对该天线的参数进行了仿真和优化,并根据优化参数进行了实物天线的制作和性能测试。结果表明,通过在共面波导地面上刻蚀非对称结构的多边形槽,可使天线的频带宽度达到2.2~8.0 GHz(S11<–10 dB),相对带宽达到114%。该天线具有良好的方向图和增益性能,满足超宽带天线的性能要求。  相似文献   

11.
This paper presents a brief overview of the Applied Centura(R)DPS(R)system,configured with silicon etch DPS Ⅱ chamber, with emphasis on discussing tuning capability for CD uniformity control. It also presents the studies of etch process chemistry and film integration impact for an overall successful gate patterning development. Discussions will focus on resolutions to key issues, such as CD uniformity, line-edge roughness, and multilayer film etching integration.  相似文献   

12.
We have fabricated the white organic light-emitting devices (WOLEDs) based on 4,4' -bis(2,2 -diphenyl vinyl)-1,1' - biphenyl (DPVBi) and phosphorescence sensitized 5,6,11,12,-tetraphenylnaphthacene (rubrene). The device structure is ITO/2T-NATA (20 nm)/NPBX (20 nm)/CBP: x%Ir(ppy)3:0.5% rubrene (8 nm)/NPBX (5 nm)/DPVBi (30 nm)/Alq(30 nm)/LiF(0.5 nm)/A1. In the devices, DPVBi acts as a blue light-emitting layer, the rubrene is sensitized by a phosphorescent material, fac tris (2-phenylpyridine) iridium [Ir(ppy)3], acts as a yellow light-emitting layer, and N,N' -bis- (1-naphthyl)- N,N' -diphenyl -1, 1' -biphenyl-4,4' -diamine (NPBX) acts as a hole transporting and exciton blocker layer, respectively. When the concentration of Ir (PPY)3 is 6wt%, the maximum luminance is 24960 cd/m^2 at an applied voltage of 15 V, and the maximum luminous efficiency is 5.17 cd/A at an applied voltage of 8 V.  相似文献   

13.
To meet the need of automatic image features extraction with high precision in visual inspection, a complete approach to automatic identification and sub-pixel center location for similar-ellipse feature is proposed. In the method, the feature area is identified automatically based on the edge attribute, and the sub-pixel center location is accomplished with the leastsquare algorithm. It shows that the method is valid, practical, and has high precision by experiment. Meanwhile this method can meet the need of instrumentation of visual inspection because of easy realization and without man-machine interaction.  相似文献   

14.
本论文提出一种在多天线MIMO信道相关性建模中小角度扩展近似理论算法,并应用于分析MIMO系统性能。分析中分别对三种不同角能量分布情况下的空间相关性研发快速近似计算法,并同时提出双模(Bi-Modal)角能量分布情况下的近似运算。通过分析这些新方法的近似效率,可以得到计算简单、复杂度低、而且符合实际的MIMO相关信道矩阵,对系统级的快速高效计算法的研究和系统级的评估以及误差分析具有重要的意义。  相似文献   

15.
In order to diagnose the laser-produced plasmas, a focusing curved crystal spectrometer has been developed for measuring the X-ray lines radiated from a laser-produced plasmas. The design is based on the fact that the ray emitted from a source located at one focus of an ellipse will converge on the other focus by the reflection of the elliptical surface. The focal length and the eccentricity of the ellipse are 1350 mm and 0.9586, respectively. The spectrometer can be used to measure the X- ray lines in the wavelength range of 0.2-0.37 nm, and a LiF crystal (200) (2d = 0.4027 nm) is used as dispersive element covering Bragg angle from 30° to 67.5°. The spectrometer was tested on Shengnang- Ⅱ which can deliver laser energy of 60-80 J/pulse and the laser wavelength is 0.35 μm. Photographs of spectra including the 1 s2p ^1P1-1s^2 ^1S0 resonance line(w), the 1s2p ^3P2-1s^2 1S0 magnetic quadrupole line(x), the 1s2p ^3P1-1 s^2 ^1S0 intercombination lines(y), the 1 s2p ^3S~1-1 s^2 ^1S0 forbidden line(z) in helium-like Ti Ⅹ Ⅺ and the 1 s2s2p ^2P3/2-1 s622s ^2S1/2 line(q) in lithium-like Ti Ⅹ Ⅹhave been recorded with a X-ray CCD camera. The experimental result shows that the wavelength resolution(λ/△ 2) is above 1000 and the elliptical crystal spectrometer is suitable for X-ray spectroscopy.  相似文献   

16.
High purity organic-tantalum precursors for thin film ALD TaN were synthesized and characterized.Vapor pressure and thermal stability of these precursors were studied.From the vapor pressure analysis,it was found that TBTEMT has a higher vapor pressure than any other published liquid TaN precursor,including TBTDET,TAITMATA,and IPTDET.Thermal stability of the alkyl groups on the precursors was investigated using a 1H NMR technique.The results indicated that the tertbutylimino group is the most stable group on TBTDET and TBTEMT as compared to the dialkylamido groups.Thermal stability of TaN precursors decreased in the following order:TBTDET > PDMAT > TBTEMT.In conclusion,precursor vapor pressure and thermal stability were tuned by making slight variations in the ligand sphere around the metal center.  相似文献   

17.
Integrated circuits (ICs) intended for increasingly sophisticated automotive applications bring unique test demands. Advanced ICs for applications such as highly integrated automatic braking system (ABS) and airbag controllers combine high voltage digital channels, significant VI demands and precise timing capability. Along with continued missioncritical reliability concerns, the trend toward higher voltage operation and increased device integration requires specialized test capabilities able to extend across the wide operating ranges found in automotive applications. Among these capabilities, automotive test requirements increasingly dictate a need for a cost-effective versatile mixed-signal pin electronics with very high data rates reaching up to 50MHz with a voltage swing of-2 V to +28 V.  相似文献   

18.
This paper reviews our recent development of the use of the large-scale pseudopotential method to calculate the electronic structure of semiconductor nanocrystals, such as quantum dots and wires, which often contain tens of thousands of atoms. The calculated size-dependent exciton energies and absorption spectra of quantum dots and wires are in good agreement with experiments. We show that the electronic structure of a nanocrystal can be tuned not only by its size,but also by its shape. Finally,we show that defect properties in quantum dots can be significantly different from those in bulk semiconductors.  相似文献   

19.
An improving utilization and efficiency of critical equipments in semiconductor wafer fabrication facilities are concerned. Semiconductor manufacturing FAB is one of the most complicated and cost sensitive environments. A good dispatching tool will make big difference in equipment utilization and FAB output as a whole. The equipment in this paper is In-Line DUV Scanner. There are many factors impacting utilization and output on this equipment group. In HMP environment one of the issues is changing of reticule in this area and idle counts due to load unbalance between equipments. Here we'll introduce a rule-based RTD system which aiming at decreasing the number of recipe change and idle counts among a group of scanner equipment in a high-mixed-products FAB.  相似文献   

20.
It is of interest to get appropriate information about the dynamic behaviour of rotating machinery parts in service. This paper presents an approach of optical vibration and deviation measurement of such parts. Essential of this method is an image derotator combined with a high speed camera or a laser doppler vibrometer (LDV).  相似文献   

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