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Compatibility between EESS (passive) in band 23.6–24 GHz and 5G in band 24.25–27.5 GHz EESS(无源)23.6 GHz频段与5G 24.25-27.5 GHz频段的兼容性
IF 1.4 4区 物理与天体物理 Q3 ASTRONOMY & ASTROPHYSICS Pub Date : 2021-05-06 DOI: 10.5802/CRPHYS.67
T. Caillet
The 24.25–27.5 GHz band was allocated to IMT (International Mobile Telecommunication) during the World Radiocommunication Conference (WRC) after studies were elaborated between this potential allocation and the services in adjacent band and in particular with Earth Exploration by satellite in adjacent band. Several studies were evaluated during the WRC-19 cycle. This document describes only the studies undertaken by some European states for the protection of Earth exploration by satellite. The elements provided in this document are the basis of the European position for WRC-19 on the protection of passive EESS in 23.6–24 GHz.
24.25-27.5 GHz频段是在世界无线电通信大会(WRC)期间分配给IMT(国际移动电信)的,此前对这一潜在分配与相邻频段的业务,特别是与相邻频段的卫星地球探测业务进行了详细研究。在WRC-19周期期间评价了几项研究。本文件仅描述了一些欧洲国家为保护卫星对地探测所进行的研究。本文件中提供的要素是WRC-19关于23.6-24 GHz无源EESS保护的欧洲立场的基础。
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引用次数: 1
Multi-beam modulated metasurface antenna for 5G backhaul applications at K-band 用于K波段5G回程应用的多波束调制元表面天线
IF 1.4 4区 物理与天体物理 Q3 ASTRONOMY & ASTROPHYSICS Pub Date : 2021-05-06 DOI: 10.5802/CRPHYS.62
J. Ruiz-García, M. Faenzi, A. Mahmoud, M. Ettorre, P. Potier, P. Pouliguen, R. Sauleau, D. González-Ovejero
We explore the use of a new modulated metasurface (MTS) antenna topology as solution for wireless backhaul at K band. The proposed structure is composed of a quasi-optical beamformer, which feeds the modulated MTS radiating aperture. These two elements are vertically stacked in a two-layer pillbox architecture to produce a very compact antenna. Furthermore, our design is able to provide several beams at different pointing angles and, hence, it offers the possibility of discrete beam steering by beam switching. The employment of a modulated MTS and the compactness given by the pillbox approach lead to a high-gain and low-profile antenna that could be an appealing solution for mobile backhaul networks.
我们探索使用一种新的调制超表面(MTS)天线拓扑结构作为K波段无线回程的解决方案。所提出的结构由一个准光学波束形成器组成,该波束形成器向调制的MTS辐射孔径馈电。这两个元件垂直堆叠在两层碉堡结构中,以产生非常紧凑的天线。此外,我们的设计能够提供不同指向角度的多个波束,因此,它提供了通过波束切换进行离散波束控制的可能性。调制MTS的使用和碉堡方法提供的紧凑性导致了高增益和低轮廓天线,这可能是移动回程网络的一个有吸引力的解决方案。
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引用次数: 3
Bandpass NGD function design for 5G microwave signal delay synchronization application 5G微波信号延迟同步应用的带通NGD功能设计
IF 1.4 4区 物理与天体物理 Q3 ASTRONOMY & ASTROPHYSICS Pub Date : 2021-05-06 DOI: 10.5802/CRPHYS.68
S. Lalléchère, L. Rajaoarisoa, L. Clavier, Raul Sanchez Galan, B. Ravelo
. Thispaperintroducesadesignmethodofsimplebandpass(BP)negativegroupdelay(NGD)topology. The fundamental specifications of BP NGD function are defined. The NGD passive topology consists of parallel resistance associated with an open-ended microstrip stub. The NGD properties and characterization with respect to the constituting stub parameters are established. The validations are performed with theoretical calculated and simulated GD, transmission and reflection coe ffi cients. The BP NGD circuit can be useful for the improvement of phase linearity and GD equalization of future 5G microwave devices.
。Thispaperintroducesadesignmethodofsimplebandpass (BP) negativegroupdelay (NGD)拓扑。定义了BP NGD函数的基本规格。NGD无源拓扑结构由与开放式微带存根相关的并联电阻组成。建立了有关构成根参数的NGD性质和表征。用理论计算和模拟的GD、透射和反射系数进行了验证。BP NGD电路可用于改善未来5G微波器件的相位线性度和GD均衡。
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引用次数: 1
Numerical modeling of downlink electromagnetic wave exposure generated by 5G beamforming antennas 5G波束形成天线下行电磁波暴露的数值模拟
IF 1.4 4区 物理与天体物理 Q3 ASTRONOMY & ASTROPHYSICS Pub Date : 2021-05-06 DOI: 10.5802/CRPHYS.61
N. Noé, F. Gaudaire
Abstract: In this paper di erent scenarios were compared for the numerical modeling of electromagnetic wave exposure to beamforming antennas. These scenarios range from the simplest (using an averaged radiation pattern) to an almost realistic one (MU-MIMO beamforming taking into account users locations) with intermediate ones. The results underline the in uence of the environment around the antennas on the distribution of the electric eld.
摘要:本文对波束形成天线中电磁波暴露的不同情况进行了数值模拟比较。这些场景的范围从最简单的(使用平均辐射方向图)到几乎现实的(考虑到用户位置的MU-MIMO波束形成),以及中间的。结果强调了天线周围环境对电场分布的影响。
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引用次数: 2
Enhanced integrated multiband HPM radiator, combining a hyperband source with a high-Q frequency selective surface 增强型集成多波段HPM散热器,结合了超波段源和高q频率选择表面
IF 1.4 4区 物理与天体物理 Q3 ASTRONOMY & ASTROPHYSICS Pub Date : 2021-05-06 DOI: 10.5802/CRPHYS.63
F. Albarracin-Vargas, Felix Cabrera Vega, C. Kasmi, David Martinez, L. Fichte
This work presents advances on the development of a resonant radiator, obtained as the augmentation of a conventional Impulse Radiating Antenna (IRA) with a Frequency Selective Surface (FSS), in the L-band. An improved passband-type FSS is obtained by exploring the Multiple Split Ring Resonators (MCSRR) unit cells to obtain a higher Q-factor radiator. The effects of a multiband and of a tunable FSS’s are also studied and verified via simulations. A variety of applications are enabled by modifying the UWB waveform from the IRA into a damped sinusoidal from the combined radiator like IEMI testing, hardening of infrastructures, cloaking of wide aperture radiators, among other. The system analysis methodology can also be applied to other FSS geometries, or the combinations of various of them.
这项工作提出了一种谐振辐射器的发展进展,作为传统脉冲辐射天线(IRA)的增强,在l波段具有频率选择表面(FSS)。通过探索多分裂环谐振器(MCSRR)单元单元,获得了更高q因子的辐射体,从而获得了改进的通带型FSS。本文还研究了多频带和可调谐FSS的影响,并通过仿真进行了验证。通过将来自IRA的UWB波形修改为来自组合辐射器的阻尼正弦,可以实现各种应用,例如IEMI测试,基础设施硬化,大孔径辐射器的隐身等。系统分析方法也可以应用于其他FSS几何形状,或它们的各种组合。
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引用次数: 0
The search for manganese incorporation in MoSe 2 monolayer epitaxially grown on graphene 石墨烯外延生长的二氧化硅单层中锰掺杂的研究
IF 1.4 4区 物理与天体物理 Q3 ASTRONOMY & ASTROPHYSICS Pub Date : 2021-05-03 DOI: 10.5802/CRPHYS.69
M. Dau, C. Vergnaud, A. Marty, F. Bonell, H. Boukari, C. Paillet, B. Hyot, H. Okuno, P. Mallet, J. Veuillen, O. Renault, M. Jamet
The introduction of magnetism in two-dimensional (2D) materials represents an intense field of research nowadays and the quest to reach above-room-temperature ordering temperatures is still underway. Intrinsic ferromagnetism was discovered in 2017 in CrI3 and Cr2Ge2Te6 in the monolayer form with low Curie temperatures. An alternative method to introduce magnetism into conventional 2D materials is substitutional doping with magnetic impurities similarly to three-dimensional diluted magnetic semiconductors. The case of Mn-doped transition metal dichalcogenide (MoS2, MoSe2, WS2, WSe2) monolayers is very interesting because combining out-of-plane ferromagnetism and valley contrast leads to ferrovalley materials. In this work, we focus on the incorporation of Mn in MoSe2 by molecular beam epitaxy on graphene which has been rarely addressed up to now. By using a multiscale characterization approach, we demonstrate that Mn atoms are incorporated into the MoSe2 monolayer up to 5 atomic percent. However, when incorporated into the film, Mn atoms tend to diffuse to the grain edges forming undefined MoxMnySez phase at grain boundaries after completion of the MoSe2 monolayer. This segregation leaves the crystalline and electronic structure of MoSe2 unmodified. Above 5%, the saturation of Mn content in MoSe2 leads to the formation of epitaxial MnSe clusters.
在二维(2D)材料中引入磁性代表了当今研究的一个激烈领域,追求达到室温以上的有序温度仍在进行中。2017年,在低居里温度下,发现了CrI3和Cr2Ge2Te6的单层本征铁磁性。将磁性引入传统二维材料的另一种方法是类似于三维稀释磁性半导体的磁性杂质的替代掺杂。掺杂锰的过渡金属二硫化物(MoS2, MoSe2, WS2, WSe2)单层是非常有趣的,因为结合了面外铁磁性和谷对比导致了铁谷材料。在这项工作中,我们重点研究了在石墨烯上通过分子束外延将Mn掺入到MoSe2中,这一问题目前很少得到解决。通过使用多尺度表征方法,我们证明Mn原子被纳入MoSe2单层高达5个原子百分比。然而,当加入到薄膜中时,Mn原子倾向于扩散到晶粒边缘,在MoSe2单层完成后,在晶界处形成未定义的MoxMnySez相。这种分离使MoSe2的晶体和电子结构未被改变。在5%以上,MoSe2中Mn含量的饱和导致外延MnSe簇的形成。
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引用次数: 3
Analysing discrete dislocation data using alignment and curvature tensors 用对准和曲率张量分析离散位错数据
IF 1.4 4区 物理与天体物理 Q3 ASTRONOMY & ASTROPHYSICS Pub Date : 2021-05-03 DOI: 10.5802/CRPHYS.60
Benedikt Weger, Satyapriya Gupta, T. Hochrainer
Analysis of large scale discrete dislocation data requires the characterisation of complex dislocation networks by suitable average quantities. In the current work, we suggest dislocation alignment tensors and closely related curvature tensors as easily extractable and intelligible measures of geometrical and topological characteristics of dislocation distributions. We provide formulae for extracting these measures from discrete dislocation data based on straight segments. Examples for interpreting and visualising these measures are provided for a simple configuration and two more involved results from discrete dislocation simulations. We suggest the alignment and curvature tensors for wider use in plasticity research.
分析大规模离散位错数据需要用合适的平均量来表征复杂位错网络。在目前的工作中,我们提出了位错对准张量和密切相关的曲率张量作为位错分布的几何和拓扑特征的易于提取和可理解的度量。我们提供了从基于直线段的离散位错数据中提取这些度量的公式。给出了解释和可视化这些措施的例子,用于一个简单的配置和两个更复杂的离散位错模拟结果。我们建议在塑性研究中更广泛地使用取向张量和曲率张量。
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引用次数: 4
Ultrafast dynamics with time-resolved ARPES: photoexcited electrons in monochalcogenide semiconductors 时间分辨ARPES的超快动力学:单硫系半导体中的光激发电子
IF 1.4 4区 物理与天体物理 Q3 ASTRONOMY & ASTROPHYSICS Pub Date : 2021-05-03 DOI: 10.5802/CRPHYS.57
Zhesheng Chen, J. Caillaux, Jiuxiang Zhang, E. Papalazarou, Jingwei Dong, J. Rueff, A. Taleb-Ibrahimi, L. Perfetti, M. Marsi
Time-resolved ARPES makes it possible to directly visualize the band dispersion of photoexcited solids, as well as to study its time evolution on the femtosecond time scale. In this article, we show how this technique can be used to monitor the ultrafast hot carrier dynamics and the conduction band dispersion in two typical monochalcogenide semiconductors: direct band gap, n-type indium selenide and indirect band gap, p-type germanium selenide. With this approach, one can directly estimate the effective electron masses of these semiconductors. Moreover, the dynamics of hot electrons in the two semiconductors are analyzed and compared. Our findings provide valuable information for the use of monochalcogenide semiconductors in future optoelectronic devices.
时间分辨ARPES可以直接观察光激发固体的能带色散,并在飞秒时间尺度上研究其时间演变。在本文中,我们展示了如何使用该技术来监测两种典型的单硫系半导体:直接带隙n型硒化铟和间接带隙p型硒化锗的超快热载流子动力学和导带色散。利用这种方法,人们可以直接估计这些半导体的有效电子质量。此外,还对两种半导体中的热电子动力学进行了分析和比较。我们的发现为单硫系半导体在未来光电器件中的应用提供了有价值的信息。
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引用次数: 0
Étude théorique de la compression de spin nucléaire par mesure quantique non destructive en continu 连续非破坏性量子测量核自旋压缩的理论研究
IF 1.4 4区 物理与天体物理 Q3 ASTRONOMY & ASTROPHYSICS Pub Date : 2021-04-29 DOI: 10.5802/CRPHYS.71
Alan Serafin, Y. Castin, Matteo Fadel, Philipp Treutlein, A. Sinatra
Nous proposons de tirer parti du tres faible couplage du spin nucleaire de l'helium 3 fondamental a son environnement pour produire des etats quantiques macroscopiques a tres longue duree de vie, ici des etats comprimes du spin nucleaire, dans un gaz en cellule a temperature ordinaire. Pour effectuer une mesure quantique non destructive sur une composante transverse du spin nucleaire collectif prealablement polarise, on allume temporairement une decharge dans le gaz, ce qui peuple l'etat metastable de l'helium 3. Le spin collectif correspondant au niveau $F=1/2$ des metastables s'hybride alors legerement avec celui des fondamentaux par collision d'echange de metastabilite. Il reste a mesurer en continu le champ lumineux sortant d'une cavite optique, ou il a interagi de maniere dispersive avec le spin collectif du metastable, pour acceder aux fluctuations du spin nucleaire. Dans un modele de trois spins collectifs couples (nucleaire, du metastable et de Stokes de la lumiere) dans l'approximation de Primakoff, et pour deux schemas de mesure, nous calculons les moments de la composante comprimee $I_z$ du spin nucleaire collectif conditionnes au signal optique moyenne sur le temps d'observation $t$. Dans le schema de comptage de photons, nous retrouvons que l'observable comprimee est $I_z^2$ plutot que $I_z$. Dans le schema de detection homodyne, nous resolvons analytiquement l'equation stochastique sur l'etat du systeme conditionne a la mesure ; la moyenne conditionnelle de $I_z$ depend lineairement du signal et la variance conditionnelle de $I_z$ n'en depend pas. La variance conditionnelle decroit comme $(Gamma_{rm sq}t)^{-1}$, ou le taux de compression $Gamma_{rm sq}$, que nous calculons explicitement, est lineaire en l'intensite lumineuse dans la cavite a faible couplage atome-champ et sature a fort couplage au taux effectif d'echange de metastabilite dans l'etat fondamental, proportionnel a la densite d'atomes metastables. Enfin, nous tenons compte de la desexcitation des metastables sur les parois, qui induit une decoherence du spin nucleaire avec un taux ramene $gamma_alpha$. Elle impose une limite $propto (gamma_alpha/Gamma_{rm sq})^{1/2}$ sur la variance conditionnelle atteinte en un temps $propto (gamma_alphaGamma_{rm sq})^{-1/2}$.
我们建议利用基本氦- 3的核自旋与其环境的非常低的耦合来产生宏观的、寿命很长的量子态,在这种情况下,是常温电池气体中核自旋的压缩态。为了对预先极化的集体核自旋的横向分量进行非破坏性量子测量,我们暂时点燃气体中的放电,使氦3处于亚稳态。对应于元表$F=1/2$水平的集体自旋通过元表交换碰撞与基本面自旋轻微混合。为了获得核自旋的波动,必须连续测量光腔发出的光场,在光腔中,光场以色散的方式与亚稳态的集体自旋相互作用。模型中的一个公益三旋夫妇(metastable核,兼Stokes Primakoff lumiere)的近似,并为计量的布局,我们计算两个时刻建造部分集体核自旋的$ $ I_z纱的光学信号的观测时间平均的$ $ t。在光子计数模式中,我们发现压缩的可观测值是$I_z^2$而不是$I_z$。在homodyne检测模式中,我们解析求解了测量条件系统状态的随机方程;$I_z$的条件均值线性依赖于信号,$I_z$的条件方差不依赖于信号。等条件方差decroit元(sq Gamma_ { - rm) ^ {1}} t $ $,或者压缩率Gamma_ rm sq}{ $明确,我们计算了甲a中,光在极坐标线材是低耦合atome-champ和饱和强耦合了该州metastabilite交流实际税率基本已成,metastables原子的密度。最后,我们考虑了亚稳态在壁上的去激发,这导致了核自旋的去相干,速率为$gamma alpha$。它对条件方差施加$propto (gamma_alpha/ gamma_ {rm sq})^{1/2}$的限制。
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引用次数: 4
In-situ evaluation of exposure induced by 5G antennas in the 3.4–3.8 GHz band 3.4-3.8 GHz频段5G天线致暴露的现场评估
IF 1.4 4区 物理与天体物理 Q3 ASTRONOMY & ASTROPHYSICS Pub Date : 2021-03-31 DOI: 10.5802/CRPHYS.65
E. Conil, J.-B. Agnani
In this paper, exposure induced in the vicinity of four pilot sites with 5G NR antennas in the 3.4–3.8 GHz band is assessed in-situ. Different manufacturers of antennas and different types of antenna are considered. Measurements are performed without any traffic, with continuous traffic in one direction and with on demand download of files. These measurements highlighted the variation in the level of exposure depending on use and led to the proposal of a new indicator to calculate the actual exposure created by 5G networks with steerable beams. This indicator results in a reduction factor that is used to assess the exposure in live conditions based on the configured maximum antenna power.
本文对四个3.4-3.8 GHz频段5G NR天线试验点附近的暴露进行了现场评估。考虑了不同的天线制造商和不同类型的天线。测量是在没有任何流量的情况下进行的,在一个方向上有连续的流量,并按需下载文件。这些测量结果突出了不同使用情况下暴露水平的差异,并提出了一个新的指标来计算具有可操纵波束的5G网络产生的实际暴露。该指标产生一个减少因子,用于根据配置的最大天线功率评估在带电条件下的暴露。
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引用次数: 1
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Comptes Rendus Physique
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