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1.
设计了一种相位控制和馈电一体化的8×8相控阵天线。将多路微带线功分器和移相器芯片集成于同一片电路板作为馈电网络并压合于阵列天线背面,形成了单端口馈电的64单元集成相控阵天线。该相控阵天线整体厚度仅2.25 mm,馈电端口至天线单元之间没有任何连接电缆,具有低剖面小型化和一体化的显著优点。电磁仿真结果显示,4.9 GHz的回波损耗小于-25 dB,最大增益为22.5 dB。此外,主极化和交叉极化隔离度为30 dB,主波束可实现-58°~62°平面扫描,具有较好的交叉极化和波束宽角域连续扫描特性,可应用于5G移动通信小型基站。  相似文献   

2.
介绍了一种小型宽带宽波束圆极化微带天线设计。该天线采用双层短路贴片,通过旋转结构设计结合多点馈电技术,实现了微带天线的宽带宽波束圆极化辐射。仿真与测试结果表明:VSWR〈2的阻抗带宽为15.9%(1.45~1.7 GHz),半功率波束宽度和3 dB轴比波束宽度在8.6%(1.45~1.58 GHz)的频带内均大于100°,天线尺寸仅为0.43λ×0.43λ×0.035λ。  相似文献   

3.
基于新馈电结构,设计了一款覆盖全球四大卫星导航系统的双频宽带贴片天线。采用了一种四分八馈电线路,以8个同轴馈电探针两两相连的方式将两路天线馈电信号合为一路,有效简化了馈电网络的复杂性,同时保证了天线辐射的增益、带宽和轴比性能。该双频辐射贴片单元采用正八边形层叠式结构设计,并在每个天线单元边缘对称添加两组矩形调谐单元,有效增加了天线辐射的波束带宽。该双频天线单元在高频1.482~1.617 GHz(波束带宽155 MHz)和低频1.191~1.252 GHz(波束带宽61 MHz)频段范围内,都能保证良好的辐射增益;高低频的3 dB轴比带宽为-130°~130°,具备良好的圆极化性能。经实物样机对比测试分析,实测结果与仿真结果基本吻合。  相似文献   

4.
新型Ka频段宽角扫描圆极化相控阵天线   总被引:1,自引:0,他引:1  
提出了一种新型的Ka频段圆极化相控阵天线。天线单元以单馈电开槽贴片天线为基础实现圆极化,通过微带贴片表面加载介质和辅助辐射器,展宽了天线波束宽度并优化了单元轴比。以该天线为阵列单元,采用顺序旋转布阵技术优化得到的2×2子阵,其辐射方向图具有良好的旋转对称性,由该子阵扩展形成的相控阵天线,有效地实现了圆极化宽角扫描特性。以8×8矩形阵列为例,仿真分析了此类二维相控阵天线波束扫描过程中的方向图和极化特性。研究结果表明,天线在工作频段内可实现方位360°、俯仰±60°扫描,扫描范围内天线增益波动和轴比均小于3 dB,同时该天线具有低剖面(高度尺寸为0.08λ0,λ0为空气介质波长)、结构简单、易于加工和集成等特点,非常适合小型化或一体化相控阵天线系统应用。  相似文献   

5.
针对现有圆极化平面阵列的扫描角受限和三维宽角扫描阵列体积大的问题,设计了一种基于阵因子方向图和单元因子方向图互补的低剖面宽角扫描圆极化阵列天线.该阵列单元采用新型圆极化正交偶极子天线,并由其组成多个圆环子阵,每一子阵内单元的法向均偏离阵列法向一个固定倾角并等间距排布在"涟漪"状金属地板上.这种阵列排布方式使得在主波束扫描至大角度时天线单元因子增益可以补偿阵因子的增益下降.设计的一个64元阵列天线的实测结果表明:在8~9 GHz工作带宽内,且波束扫描覆盖0°~±62°,各阵元的有源驻波比均小于2.1,中心频点扫描增益起伏小于1.71 dB,扫描波束的圆极化轴比小于2 dB.  相似文献   

6.
设计了一副改进的非对称平衡对拓Vivaldi天线。辐射贴片外边缘用3阶多项式曲线修正,以实现很宽的阻抗带宽。在天线口径处嵌入一个金属贴片作引向器以改善天线的辐射特性。对辐射贴片引入非对称性,使得E面波束偏离得到进一步补偿。实测结果表明,该天线具有极宽的工作带宽,在2~40 GHz内的增益大于0 dBi,且在15~30 GHz内的增益大于14 dBi;E面的波束偏离在6~40 GHz频率范围内小于3°。该天线具有结构简单、尺寸紧凑(44 mm×98 mm)以及方向图稳定等优点。该天线能够较好地应用于相控阵、超宽带系统等。  相似文献   

7.
姜兴  程林  李晓峰  彭麟  廖欣 《电讯技术》2023,(1):131-136
针对宽波束天线在移动通信中的应用,实现偶极子阵列天线的宽角域扫描覆盖,设计了一款宽波束天线单元以及1×16相控线阵。采用正交对称振子结构实现±45°方向辐射,振子采用椭圆环结构实现了宽阻抗带宽和宽波束,通过加载梯形结构降低了频段和实现小型化。实测结果表明,天线单元在6.425~7.125 GHz的频带内电压驻波比小于1.3,具有38.8%的相对阻抗带宽,在工作频带内其端口隔离度优于28 dB,3 dB波束宽度在频带内均大于126°,能够很好满足现阶段对阵列天线小型化、宽频带以及宽角域扫描的要求,在移动基站等领域有广阔的应用前景。  相似文献   

8.
姜兴  王开发  廖欣  孙靖虎  王继恒  杨明 《电讯技术》2021,61(12):1592-1598
针对宽波束天线在车载雷达中的应用,突破角雷达方位面3 dB波束宽度的限制,实现微带阵列天线在水平面的宽波束覆盖,设计了一款1×10串馈微带双层结构天线。线阵单元采用道尔夫-切比雪夫(Dolf-Chebyshev)综合法电流分布来达到降低天线俯仰面副瓣的效果,在串馈阵列上方加载寄生贴片和介质基板拓展天线方位面的3 dB波束宽度。分析了双层天线展宽波束的原理,加工并实测了双层宽波束天线,其方位面的3 dB波束宽度为134.6°,增益达到10.6 dB,副瓣电平为-19.8 dB,可以满足车载角雷达天线需求。  相似文献   

9.
一种45°极化的毫米波二维宽带宽角扫描相控阵   总被引:1,自引:0,他引:1       下载免费PDF全文
曾羽  丁霄 《微波学报》2021,37(3):52-55
设计了一款工作于Ka波段的+45°极化宽带宽角扫描相控阵。基于电磁镜像原理,通过嵌入人工磁导体,提出了一款具备宽波束辐射能力的+45°极化天线单元,其相对带宽达18.2%,水平方位面的3 dB 波束宽度达114°,展示出宽角扫描潜能。将上述单元组成4×16 均匀面阵并研究相控阵宽角扫描特性。计算结果表明,该面阵能在水平方位面实现±80°宽角扫描,在垂直方位面实现-20°~+30°扫描。  相似文献   

10.
设计了一款宽波束的圆极化天线单元以及1×4的天线阵列,实现了一维的宽角圆极化扫描.天线单元由单层的辐射贴片和介质基片集成波导(substrate integrated waveguide,SIW)背腔构成,通过在辐射贴片上切角微扰和开U型槽实现右旋圆极化,并利用SIW背腔缝隙展宽波束.同时利用SIW背腔减小阵列单元间的互耦,实现宽角圆极化扫描.仿真与测试结果表明,天线阵列实现了扫描角为-53°~57°,3 dB波束宽度覆盖范围为-76°~79°,在主波束扫描覆盖范围内轴比(axial ratio,AR)均小于3 dB,且在扫描范围内增益变化平稳,可实现良好的宽角范围的圆极化扫描特性.  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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