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北极航道短波组网通信效应及极区粒子沉降对其影响的研究

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极地研究 2024年第1期36卷 12-25页

作者：葛淑灿徐彬李海龙徐彤朱梦言蒙林吴健中国电波传播研究所山东青岛266107 电子科技大学电子科学与工程学院四川成都610000

北极航道是指穿过北冰洋,连接大西洋和太平洋的海上航道,北极航道的快速发展对世界政治经济格局将产生深远影响。现有极区单台站短波通信易受极区恶劣空间环境因素的影响,可通率不高,无法对北极航道船舶的安全航行提供可靠保障。本文针... 详细信息

北极航道是指穿过北冰洋,连接大西洋和太平洋的海上航道,北极航道的快速发展对世界政治经济格局将产生深远影响。现有极区单台站短波通信易受极区恶劣空间环境因素的影响,可通率不高,无法对北极航道船舶的安全航行提供可靠保障。本文针对北极航道短波通信保障需求,搭建基于确定性模型的短波通信覆盖区评估理论框架,探究复折射指数射线追踪功率计算方法,进而评估北极航道短波组网通信效应,同时开展了高能粒子沉降等极区电离层扰动对北极航道短波传播效应影响的研究,旨在为短波组网北极航道通信效能评估与站网规划设计提供理论基础。

关键词：短波组网通信极区粒子沉降射线追踪北极航道东北航道

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空间等离子体云精细化仿真及传播特性研究

电波科学学报 2024年第1期39卷 56-64页

作者：谢守志赵海生许正文任光亮王成葛淑灿西安电子科技大学综合业务网理论及关键技术国家重点实验室西安710071 中国电波传播研究所电波环境特性及模化技术重点实验室青岛266107 中国空间技术研究院钱学森实验室北京100094

在电离层中释放钐(Sm)等活泼金属气体,通过光致电离或化学电离,能够人工生成空间等离子体云,以其作为散射体,可开展超短波超视距通信和探测研究。本文开展了电离层Sm释放的精细化效应仿真研究,考虑了热层风场、地磁场、Sm释放速度和流... 详细信息

在电离层中释放钐(Sm)等活泼金属气体,通过光致电离或化学电离,能够人工生成空间等离子体云,以其作为散射体,可开展超短波超视距通信和探测研究。本文开展了电离层Sm释放的精细化效应仿真研究,考虑了热层风场、地磁场、Sm释放速度和流量、运载器飞行速度等参量对Sm在电离层中扩散过程的影响。同时,采用射线追踪方法,研究了空间等离子体云的电波传播特性。结果表明释放参数和环境参数对等离子体云的形态和演化过程具有重要影响,等离子云在不同剖面形态各异,沿地磁场方向及风场方向出现明显拉伸,进一步对等离子体云的传播效应产生影响,导致电波在等离子体云不同剖面传播特性出现差异。

关键词：电离层化学物质释放钐空间等离子体云电波传播

Comparison of the reaction of polar mesosphere winter echoes and polar mesosphere summer echoes to high-frequency heating in terms of modulated characteristics

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Earth and Planetary Physics 2023年第2期7卷 247-256页

作者： Safi Ullah HaiLong Li Abdur Rauf Shahid Ullah Khan Sufyan Ullah Khan shucan ge Bin Wang MaoYan Wang Lin Meng School of Electronic Science and Engineering University of Electronic Science and Technology of ChinaChengdu 610054China Department of Physics Riphah International University Islamabad CampusIslamabad 45210Pakistan Department of Physics University of Science and Technology BannuBannu 28101Pakistan National Key Laboratory of Electromagnetic Environment China Research Institute of Radiowave PropagationQingdao 266107China School of Physics University of Electronic Science and Technology of ChinaChengdu 610054China

In this work,for the first time,we have analyzed and compared the responses of polar mesosphere winter echoes(PMWE)and their summer counterpart,polar mesosphere summer echoes(PMSE),to high-frequency(HF)heating in terms of modulated characteristics(i.e.,backscatter intensity reduction,recovery,and overshoot).Both PMWE and PMSE observations were from the same site(Tromsφ,Norway;69.6°N,19.2°E)and radar(EISCAT[European Incoherent Scatter Scientific Association]very high frequency,224 MHz).The heating patterns of both PMWE and PMSE were found to be similar;however,PMSE was more greatly affected by HF *** mesosphere summer echoes showed recovery and overshoot more frequently than did *** addition,the mean recovery and overshoot of PMSE were greater than those of *** associated electron temperature enhancement was estimated for both PMWE and PMSE and showed that,compared with PMWE,the electron temperature enhancement was more significant in *** strong heating effects on PMSE may be due to the considerable increase in electron temperature.

关键词： polar mesosphere winter echo polar mesosphere summer echo electromagnetic wave heating experiment dusty plasma ionosphere

Exploring the occurrence rate of PMSE-Es by Digisonde at Tromsø

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Earth and Planetary Physics 2021年第2期5卷 187-195页

作者： HaiLong Li shucan ge Lin Meng MaoYan Wang Abdur Rauf Safi Ullah School of Electronic Science and Engineering University of Electronic Science and Technology of ChinaChengdu 610054China National Key Laboratory of Electromagnetic Environment China Research Institute of Radiowave PropagationQingdao 266107China School of Physics University of Electronic Science and Technology of ChinaChengdu 610054China

Polar mesosphere summer echoes(PMSE)are observed simultaneously with Digisonde and EISCAT VHF *** phenomenon of irregular Es layers is called PMSE-like or PMSE-Es(Polar Mesosphere Summer Echoes-Es)and has some relationship with real *** this paper,the characteristics of irregular Es layers at 80–100 km were observed by Digisonde at Tromsøduring 2003–2014 are statistically analyzed with *** diurnal,day-to-day and year-to-year variations and discrepancies of occurrence rate between PMSE and PMSE-Es are compared with the statistical results observed by Esrange MST radar(ESRAD),and the reasons are *** results show that the trends in the occurrence rate of PMSE-Es are similar to the trends in the occurrence rate of PMSE,but there are some notable *** occurrence rate of PMSE-Es is much lower than the occurrence rate of *** minimum value of PMSE-Es appears 1–2 hours earlier than the minimum value of the PMSE occurrence rate,while PMSE-Es appear earlier than PMSE in the *** addition,there is a significant positive correlation between the annual average occurrence rates of PMSE and *** is a relatively important occurrence in the polar *** of its characteristics can provide new ideas and methods for studying the formation mechanism of PMSE.

关键词： Polar mesosphere summer echoes Digisonde EISCAT VHF radar PMSE-Es Esrange MST radar

Effect of ions on conductivity and permittivity in the Polar Mesosphere Summer Echoes region

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Earth and Planetary Physics 2021年第2期5卷 196-204页

作者： Safi Ullah HaiLong Li Abdur Rauf Lin Meng Bin Wang shucan ge MaoYan Wang School of Electronic Science and Engineering University of Electronic Science and Technology of ChinaChengdu 610054China Terahertz Science and Technology Key Laboratory of Sichuan Province Chengdu 610054China National Key Laboratory of Electromagnetic Environment China Research Institute of Radiowave PropagationQingdao 266107China School of Physics University of Electronic Science and Technology of ChinaChengdu 610054China

For the first time,the effect of ions on complex conductivity and permittivity of dusty plasma at Polar Mesosphere Summer Echoes(PMSE)altitude is *** of ions higher mass and smaller thermal velocity,generally,their effects are not considered in the study of electromagnetic properties of dusty *** this study,we modified the equations of conductivity and permittivity by adding the effect of *** the PMSE altitude region between 80 and 90 km,a local reduction in electron density(i.e.,an electron biteout),is produced by electron absorption onto dust *** bite-out condition contains high dust density and smaller electron *** simulation results in comparatively strong bite-out conditions,we found that the ion effects on conductivity become significant with smaller dust size,lower electron temperature,and lower neutral *** comparatively weak bite-out conditions,the ion effects on conductivity become significant with larger dust size,higher electron temperature,and higher neutral *** the other hand,for different dust sizes,electron temperatures and neutral density,the ion effects on complex permittivity become significant only in very strong bite-out *** on these simulation results,we conclude that,in the absence of electron bite-out conditions,the effect of ions on complex conductivity and permittivity is not significant and can be ***,during bite-out conditions,the effect of ions becomes significant and cannot be ignored because it significantly changes the conductivity and permittivity of dusty plasmas.

关键词： PMSE electromagnetic waves collision and charging effect conductivity and permittivity

On the radar frequency dependence of polar mesosphere summer echoes

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Earth and Planetary Physics 2020年第6期4卷 571-578页

作者： shucan ge HaiLong Li Lin Meng MaoYan Wang Tong Xu Safi Ullah Abdur Rauf Abdel Hannachid School of Electronic Science and Engineering University of Electronic Science and Technology of ChinaChengdu 610054China School of Physics University of Electronic Science and Technology of ChinaChengdu 610054China National Key Laboratory of Electromagnetic Environment China Research Institute of Radio Wave PropagationQingdao 266107China Department of Meteorology Stockholm UniversitySE-106-91StockholmSweden

Polar mesosphere summer echoes(PMSEs)are very strong radar echoes in the polar mesopause in local *** we present the frequency dependence of the volume reflectivity and the effect of energetic particle precipitation on modulated PMSEs by using PMSEs observations carried out by European Incoherent SCATter(EISCAT)heating equipment simultaneously with very high frequency(VHF)radar and ultra high frequency(UHF)radar on 12 July *** to the experimental observations,the PMSEs occurrence rate at VHF was much higher than that at UHF,and the altitude of the PMSEs maximum observed at VHF was higher than that at *** regions were observed by VHF radar between high energetic particle precipitation and the *** addition,highfrequency heating had a very limited impact on PMSEs when the UHF electron density was enhanced because of energetic particle *** addition,an updated qualitative method was used to study the relationship between volume reflectivity and *** volume reflectivity was found to be inversely proportional to the fourth power of radar *** theoretical and experimental results provide a definitive data foundation for further analysis and investigation of the physical mechanism of PMSEs.

关键词： Polar mesosphere summer echoes artificial electron heating volume reflectivity energetic particle precipitation

Characteristic analysis of layered PMSEs measured with different elevation angles at VHF based on an experimental case

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地球与行星物理：英文版 2021年第1期5卷 42-51页

作者： shucan ge HaiLong Li Bin Xu Tong Xu Lin Meng MaoYan Wang Abdel Hannachi MengYan Zhu Lina Broman Safi Ullah Abdur Rauf School of Electronic Science and Engineering University of Electronic Science and Technology of ChinaChengdu 610054China National Key Laboratory of Electromagnetic Environment China Research Institute of Radiowave PropagationQingdao 266107China School of Physics University of Electronic Science and Technology of ChinaChengdu 610054China Department of Meteorology Stockholm UniversityStockholm SE-106-91Sweden

Polar Mesosphere Summer Echoes(PMSEs)are very strong radar echoes observed at altitudes near the polar summer *** of the essential properties of these radar echoes is that they can give useful diagnostic information about the physics of the scattering *** this paper,the related characteristics of PMSEs measured with the European Incoherent SCATter Very High Frequency(EISCAT VHF)224 MHz radar on 13–15 July 2010 are studied at different elevation angles from 78°to 90°.It is found that the PMSEs peak power and strongest PMSEs average power occur at the same elevation *** interesting is that the strongest PMSEs occur at off-vertical angles when a PMSEs has a layered(multilayer)*** reflection may have more significant effects on PMSEs when there are double or multilayer *** explanations regarding these observations are discussed.

关键词： Polar Mesosphere Summer Echoes off-vertical angles layered structure

基于新型数据分析软件的极区中层强雷达回波研究

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电子科技大学学报 2021年第6期50卷 868-876页

作者：葛淑灿李海龙蒙林 RAUF Abdur ULLAH Safi 电子科技大学电子科学与工程学院成都611731

该文利用极区中层异常回波及云粒子数据提取分析软件(PMEC_DEAS)处理雷达回波及云粒子数据集,并进行回波特性研究。以通过PMEC_DEAS分析的短期和长期极地中层夏季回波(polar mesosphere summer echoes,PMSE)和极地中层云(polar mesosphe... 详细信息

该文利用极区中层异常回波及云粒子数据提取分析软件(PMEC_DEAS)处理雷达回波及云粒子数据集,并进行回波特性研究。以通过PMEC_DEAS分析的短期和长期极地中层夏季回波(polar mesosphere summer echoes,PMSE)和极地中层云(polar mesospheric clouds,PMC)数据为例,研究了PMSE出现率与PMC之间的相关性。研究发现短期的PMSE出现率和PMC之间的相关性不显著,长期的双层PMSE出现率与PMC之间呈正相关关系。这表明双层PMSE与PMC密切相关,这与现有的结论一致。以此可以看出,PMEC_DEAS可以有效地适应所研究事件的复杂特征变化,并具有良好的鲁棒性。此外,利用PMEC_DEAS软件分析所得的数据具有更好的稳定性和兼容性,与目前的主流数据分析软件相比更具便捷性和实用性。

关键词：极区中层异常回波及云粒子数据提取分析软件极区中层云极区中层夏季回波鲁棒性

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中低纬度低电离层物理模型构建研究

电波科学学报 2019年第2期34卷 196-202页

作者：朱梦言徐彤胡艳莉吴健葛淑灿中国电波传播研究所电波环境特性及模化技术重点实验室青岛266107 电子科技大学电子科学与工程学院成都610054

从粒子连续性方程出发,考虑电离、复合、附着等物理过程,初步建立了一个中低纬度地区低电离层(60～120 km)稳态物理模型.该模型涉及145个离子化学反应,能够给出23个正离子、11个负离子、12种中性粒子及电子密度分布.模拟结果表明:NO^+... 详细信息

从粒子连续性方程出发,考虑电离、复合、附着等物理过程,初步建立了一个中低纬度地区低电离层(60～120 km)稳态物理模型.该模型涉及145个离子化学反应,能够给出23个正离子、11个负离子、12种中性粒子及电子密度分布.模拟结果表明:NO^+及水化聚合离子NO^+(H_2O)_n、H^+(H_2O)_n等是低电离层正离子的主要成分;以CO^-_3及O^-_3为主的负离子成分仅在80 km以下高度占优,导致在较低高度电子密度远小于离子密度.以100°E不同纬度(5°N、25°N、45°N)为例,与国际参考电离层(international ionosphere reference 2016,IRI-2016)模型进行比较,结果表明该物理模型能够较好地描述中低纬度低电离层电子密度随高度变化、周日变化等形态学特征.

关键词：低电离层电子密度离子密度物理模型光电离离子化学