2021 USNC-URSI Radio Science Meeting (USCN-URSI RSM)最新文献

On a modified form of Pocklington equation for thin, bent wires 用波克林顿方程的一种修正形式来描述细而弯曲的导线

2021 USNC-URSI Radio Science Meeting (USCN-URSI RSM) Pub Date : 2021-08-09 DOI: 10.23919/USNC-URSIRSM52661.2021.9552346

A. Voronovich, P. E. Johnston, R. Lataitis

{"title":"On a modified form of Pocklington equation for thin, bent wires","authors":"A. Voronovich, P. E. Johnston, R. Lataitis","doi":"10.23919/USNC-URSIRSM52661.2021.9552346","DOIUrl":"https://doi.org/10.23919/USNC-URSIRSM52661.2021.9552346","url":null,"abstract":"Classical integral or integro-differential equations of the Pocklington and Hallen type, describing radiation and scattering of electromagnetic fields by thin, ideally conducting wires, are of significant practical interest and have been extensively studied. These equations follow from the boundary condition that requires a vanishing of the tangential component of the total electric field at the wire surface. The total electric field consists of both a known incident field and a scattered field that is due to a generally unknown current induced in the wire. The scattered electric field for a given point on the wire surface consists both of a “far” field at distant points significantly exceeding the wire's radius $a$, and by a “near” field due to arbitrarily nearby points. Expressions for the “near” field include a logarithmic singularity in the kernel of the associated Pocklington equation. This singularity is an important feature that makes the Pocklington equation solvable and well-posed. Thus, the Pocklington equation in its standard form can be considered as a Fredholm integral equation of the first kind with a singular kernel.","PeriodicalId":365284,"journal":{"name":"2021 USNC-URSI Radio Science Meeting (USCN-URSI RSM)","volume":"48 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-08-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127835085","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Rain Attenuation at THz Frequencies from Historical Data Collected in Brasilia, Brazil 来自巴西巴西利亚历史数据的太赫兹频率的雨衰减

2021 USNC-URSI Radio Science Meeting (USCN-URSI RSM) Pub Date : 2021-08-09 DOI: 10.23919/USNC-URSIRSM52661.2021.9552345

L. Morais, L. Menezes, P. Moraes

引用次数: 2

Minima in phase space density and how they relate to the multi-MeV electron radiation belt depletions 相空间密度的最小值及其与多兆电子伏电子辐射带损耗的关系

2021 USNC-URSI Radio Science Meeting (USCN-URSI RSM) Pub Date : 2021-08-09 DOI: 10.23919/USNC-URSIRSM52661.2021.9552341

A. Drozdov, H. Allison, Y. Shprits, M. Usanova, A. Saikin

{"title":"Minima in phase space density and how they relate to the multi-MeV electron radiation belt depletions","authors":"A. Drozdov, H. Allison, Y. Shprits, M. Usanova, A. Saikin","doi":"10.23919/USNC-URSIRSM52661.2021.9552341","DOIUrl":"https://doi.org/10.23919/USNC-URSIRSM52661.2021.9552341","url":null,"abstract":"The Earth's radiation belts include electrons over a wide energy range. The dynamics of electrons can differ significantly, depending on the energy. In comparison to ~MeV energies, multi-MeV electrons are less predictable during geomagnetic storms [1], as their population can be depleted, enhanced, or remain unchanged, with nearly equal probability [2]. The depletion of electrons can be reversible (adiabatic) or irreversible, due to wave-particle interactions and loss at the outer boundary. Nonadiabatic changes can be identified by analyzing phase space density (PSD) as a function of the three adiabatic invariants. Fast-localized losses, such as interaction with electromagnetic ion cyclotron (EMIC) waves, can produce deepening PSD minima [3]. The EMIC waves are very effective in scattering multi-MeV electrons and can create sharp gradients in pitch angle distributions, although they do not resonate with nearly equatorial mirroring electrons. The depletion of electrons in a wide range of pitch angles occurs with assistance of the hiss and chorus waves [4]. However, the local minimum in PSD may be also observed due to outward radial diffusion with either subsequent refilling of the radiation belts or local acceleration. In this case, the formation of the minima will not result in continued deepening [5].","PeriodicalId":365284,"journal":{"name":"2021 USNC-URSI Radio Science Meeting (USCN-URSI RSM)","volume":"11 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-08-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132239886","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Wave Generation and Wave-Particle Interaction Using Space-Based, RF, Linear Electron Accelerators 利用天基射频线性电子加速器产生波和波粒相互作用

2021 USNC-URSI Radio Science Meeting (USCN-URSI RSM) Pub Date : 2021-08-09 DOI: 10.23919/USNC-URSIRSM52661.2021.9552348

G. Reeves

{"title":"Wave Generation and Wave-Particle Interaction Using Space-Based, RF, Linear Electron Accelerators","authors":"G. Reeves","doi":"10.23919/USNC-URSIRSM52661.2021.9552348","DOIUrl":"https://doi.org/10.23919/USNC-URSIRSM52661.2021.9552348","url":null,"abstract":"Active experiments in space provide the opportunity to perturb the natural environment with known and controllable conditions. As such, active experiments are well-suited to studying wave-particle and wave-wave interactions. Active experiments were much more common in the 1970's and 1980's than they are today. Results from rockets, the Space Shuttle, and satellites provided important contributions to our understanding of both linear and non-linear plasma physics. New technologies provide new opportunities for using electron beams to probe the physics of the magnetosphere and, in particular, the radiation belts. In particular, newly-developed RF linear accelerator (linac) technologies can finally be adapted for space enabling much more powerful and flexible options for electron beam wave generation. Similarly, wave receivers, particle detectors, digital electronics, and high telemetry rates now allow detailed measurements of the artificially-generated waves and their effects on the local plasma environment. Specifically, full waveform capture of the 3D electric and magnetic fields allow detailed understanding of the properties of the waves including spectra, wave normal distributions, polarization, etc.","PeriodicalId":365284,"journal":{"name":"2021 USNC-URSI Radio Science Meeting (USCN-URSI RSM)","volume":"221 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-08-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"134333474","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Using Ray Tracing to Model the Plasmaspheric Wave Field for Active Experiments in Space 利用射线追踪技术模拟空间主动实验等离子体波场

2021 USNC-URSI Radio Science Meeting (USCN-URSI RSM) Pub Date : 2021-08-09 DOI: 10.23919/USNC-URSIRSM52661.2021.9552372

J. Holmes, G. Delzanno, C. Jeffery, P. Colestock

引用次数: 0

First observations and results from the Very-Low-Frequency Propagation Mapper (VPM) CubeSat mission 极低频传播映射器(VPM)立方体卫星任务的首次观测和结果

2021 USNC-URSI Radio Science Meeting (USCN-URSI RSM) Pub Date : 2021-08-09 DOI: 10.23919/USNC-URSIRSM52661.2021.9552351

R. Marshall, R. Reid, M. Usanova, M. Starks, G. Wilson

引用次数: 0

Millimeter Wave Antenna Design for On-Chip Electro-Optical Sensing Devices Using Optical Up-Conversion 基于光上转换的片上光电传感器件毫米波天线设计

2021 USNC-URSI Radio Science Meeting (USCN-URSI RSM) Pub Date : 2021-08-09 DOI: 10.23919/USNC-URSIRSM52661.2021.9552338

A. Akhiyat, Pawan Gaire, J. Volakis

引用次数: 0

Analysis of a Sub-GHz-Band Diffraction Propagation Model for Maritime Application 海上应用的亚ghz波段衍射传播模型分析

2021 USNC-URSI Radio Science Meeting (USCN-URSI RSM) Pub Date : 2021-08-09 DOI: 10.23919/USNC-URSIRSM52661.2021.9552366

Hiroki Ichiba, Yuji Ito, Toshihiko Hamasaki

引用次数: 0

Progress and Error Dependencies of Matched Filter Maximum Cyclone Wind Retrievals Using CYGNSS CYGNSS匹配滤波器最大气旋风反演的进展与误差依赖关系

2021 USNC-URSI Radio Science Meeting (USCN-URSI RSM) Pub Date : 2021-08-09 DOI: 10.23919/USNC-URSIRSM52661.2021.9552358

Mohammad M. Al-Khaldi, J. Johnson, S. Katzberg, Young-Heac Kang, E. Kubatko, S. Gleason

{"title":"Progress and Error Dependencies of Matched Filter Maximum Cyclone Wind Retrievals Using CYGNSS","authors":"Mohammad M. Al-Khaldi, J. Johnson, S. Katzberg, Young-Heac Kang, E. Kubatko, S. Gleason","doi":"10.23919/USNC-URSIRSM52661.2021.9552358","DOIUrl":"https://doi.org/10.23919/USNC-URSIRSM52661.2021.9552358","url":null,"abstract":"This presentation reports on progress relating to a storm characterization approach using spaceborne Global Navigation Satellite System Reflectometry (GNSS-R) measurements from the Cyclone Global Navigation Satellite System (CYGNSS) mission. The retrieval concept is based on the use of a forward model for CYGNSS returns, which can produce predicted waveforms for parametric storm models having varying storm features, with particular emphasis placed on the storm maximum wind speed. A “matched filter” approach is then adopted by correlating predicted returns with those observed throughout an entire CYGNSS overpass of a storm; the correlation is performed between predicted and measured DDMs normalized by their root-mean-square (RMS) amplitudes. Storm parameters producing the maximum correlation and minimum RMS error (RMSE) values are then designated the retrieved value from which a complete parametric wind field for storm surge simulation can be generated. It is noted that the utility of this formulation is not limited to tracks passing through the storm eye, making “near-miss” tracks equally usable for attempting to retrieve storm information.","PeriodicalId":365284,"journal":{"name":"2021 USNC-URSI Radio Science Meeting (USCN-URSI RSM)","volume":"6 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-08-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128929879","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Invisibility of Triangular Anti-Isorefractive DNG Prisms Illuminated by Multiple Incident Plane Waves 多重入射平面波照射抗等折光DNG三角形棱镜的不可见性

2021 USNC-URSI Radio Science Meeting (USCN-URSI RSM) Pub Date : 2021-08-09 DOI: 10.23919/USNC-URSIRSM52661.2021.9552357

P. Uslenghi

引用次数: 3