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2020 XXXIIIrd General Assembly and Scientific Symposium of the International Union of Radio Science最新文献

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Wave-Optics Analysis of HF Propagation through Traveling Ionospheric Disturbances and Developing Plasma Bubbles 高频通过电离层扰动和等离子体气泡传播的波光学分析
2020 XXXIIIrd General Assembly and Scientific Symposium of the International Union of Radio Science Pub Date : 2020-08-01 DOI: 10.23919/URSIGASS49373.2020.9232348
C. Carrano, J. Retterer, K. Groves, G. Crowley, T. Duly, D. Hunton
{"title":"Wave-Optics Analysis of HF Propagation through Traveling Ionospheric Disturbances and Developing Plasma Bubbles","authors":"C. Carrano, J. Retterer, K. Groves, G. Crowley, T. Duly, D. Hunton","doi":"10.23919/URSIGASS49373.2020.9232348","DOIUrl":"https://doi.org/10.23919/URSIGASS49373.2020.9232348","url":null,"abstract":"We apply a wave-optics technique to model the propagation of high-frequency (HF) waves through simulated traveling ionospheric disturbances (TIDs) and developing plasma bubbles at low latitudes. Wave-optics is derived from a forward-propagation approximation of the Helmholtz equation governing the electric field in the frequency domain. The technique is implemented using the split-step Fourier approach commonly referred to as the multiple phase screen method (MPS). At an intermediate step in the computation, the electric field along each phase screen is expressed explicitly in terms of the angular spectrum of plane waves intersecting the screen.We use this approach to produce angle-of-arrival “maps,” which depict the spectrum of angle-of-arrival (AOA) at all locations on the ground. These AOA maps identify all radio propagation modes reaching the receiver along with their individual amplitudes. With the wave-optics approach there is no need to ‘home’ rays to identify the propagation modes that are present. A full-wave technique, wave-optics accurately represents the interaction (via diffraction) between the different propagation modes, which can result in fading of the received HF signal. Ray-tracing techniques neglect diffraction and therefore cannot represent these interactions nor the signal fading they produce.","PeriodicalId":438881,"journal":{"name":"2020 XXXIIIrd General Assembly and Scientific Symposium of the International Union of Radio Science","volume":"34 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2020-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126072141","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: 6
Nonlinear phenomena in the high latitude ionosphere F region induced by O-and X-mode HF pumping at EISCAT 高纬电离层F区的非线性现象由EISCAT的o和x模HF抽运引起
2020 XXXIIIrd General Assembly and Scientific Symposium of the International Union of Radio Science Pub Date : 2020-08-01 DOI: 10.23919/URSIGASS49373.2020.9231980
N. Blagoveshchenskaya, T. Borisova, A. Kalishin, I. Häggström
{"title":"Nonlinear phenomena in the high latitude ionosphere F region induced by O-and X-mode HF pumping at EISCAT","authors":"N. Blagoveshchenskaya, T. Borisova, A. Kalishin, I. Häggström","doi":"10.23919/URSIGASS49373.2020.9231980","DOIUrl":"https://doi.org/10.23919/URSIGASS49373.2020.9231980","url":null,"abstract":"Experimental results from multi-instrument observations at the EISCAT HF heating facility at Tromsø, Norway, are presented. We compare distinctive features of artificial plasma turbulences in the high latitude ionosphere F-region induced by powerful HF electromagnetic waves with the ordinary (O-mode) and extraordinary (X-mode) polarization.","PeriodicalId":438881,"journal":{"name":"2020 XXXIIIrd General Assembly and Scientific Symposium of the International Union of Radio Science","volume":"14 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2020-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114174486","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
Study of the Crowd Behavior in Campus Based on WIFI Probe and Time Series Analysis 基于WIFI探测和时间序列分析的校园人群行为研究
2020 XXXIIIrd General Assembly and Scientific Symposium of the International Union of Radio Science Pub Date : 2020-08-01 DOI: 10.23919/URSIGASS49373.2020.9232029
Liang Chen, Zhi Gang Chen, C. Huang, Yong Qiu Lu, J. Yang, Ming Huang
{"title":"Study of the Crowd Behavior in Campus Based on WIFI Probe and Time Series Analysis","authors":"Liang Chen, Zhi Gang Chen, C. Huang, Yong Qiu Lu, J. Yang, Ming Huang","doi":"10.23919/URSIGASS49373.2020.9232029","DOIUrl":"https://doi.org/10.23919/URSIGASS49373.2020.9232029","url":null,"abstract":"Recognizing and understanding the behavior of the campus crowd is of great significance for improving the management capabilities of the campus. The increasingly abundant of mobile terminal WiFi signals provide a unique data source for studying the crowd behavior. A WiFi-based personnel activity monitoring system is developed in this paper. Through monitoring and analyzing the MAC address (Media Access Control Address), RSSI(Received Signal Strength Indication) and Wireless AP (Access Point) in and around the Science Museum, Huaizhou building of Yunnan University, the association between WIFI signal and the crowd behavior is studied. Time series analysis is used to make predictions, and some valuable information about the gathering and activity status of crowd in campus is obtained. It provides an experimental platform for studying the dynamic behavior of people in campus and other crowd areas.","PeriodicalId":438881,"journal":{"name":"2020 XXXIIIrd General Assembly and Scientific Symposium of the International Union of Radio Science","volume":"28 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2020-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114204998","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
Design and Development of a Wide-Field Fully Cryogenic Phased Array Feed for Arecibo 阿雷西博广域全低温相控阵馈源的设计与研制
2020 XXXIIIrd General Assembly and Scientific Symposium of the International Union of Radio Science Pub Date : 2020-08-01 DOI: 10.23919/URSIGASS49373.2020.9232378
M. Burnett, Jakob W. Kunzler, E. Nygaard, B. Jeffs, K. Warnick, D. Campbell, G. Cortés-Medellín, S. Parshley, A. Vishwas, P. Perillat, D. Roshi
{"title":"Design and Development of a Wide-Field Fully Cryogenic Phased Array Feed for Arecibo","authors":"M. Burnett, Jakob W. Kunzler, E. Nygaard, B. Jeffs, K. Warnick, D. Campbell, G. Cortés-Medellín, S. Parshley, A. Vishwas, P. Perillat, D. Roshi","doi":"10.23919/URSIGASS49373.2020.9232378","DOIUrl":"https://doi.org/10.23919/URSIGASS49373.2020.9232378","url":null,"abstract":"Brigham Young University (BYU), in collaboration with Cornell University, is developing the Advanced Cryogenic L-band Phased Array Camera for Arecibo (ALPACA) as a user provided facility instrument on the Arecibo 305 m radio telescope. This instrument will consist of a fully cryogenic 69-element phased array feed (PAF) and real-time digital beamformer back end capable of producing 40 simultaneous dual polarized beams with approximately 305 MHz of instantaneous bandwidth at 1.4 GHz. The target design goal is to operate with a system noise temperature of 25 K. We report on simulation results and a preliminary overview of the design and progress of the instrument’s development.","PeriodicalId":438881,"journal":{"name":"2020 XXXIIIrd General Assembly and Scientific Symposium of the International Union of Radio Science","volume":"62 9","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2020-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121012307","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: 4
A Microwave Diagnostic Technique for Early-Stage Brain Stroke Characterization 早期脑卒中特征的微波诊断技术
2020 XXXIIIrd General Assembly and Scientific Symposium of the International Union of Radio Science Pub Date : 2020-08-01 DOI: 10.23919/URSIGASS49373.2020.9232318
A. Fedeli, A. Randazzo, A. Sciarrone, I. Bisio, F. Lavagetto, M. Pastorino
{"title":"A Microwave Diagnostic Technique for Early-Stage Brain Stroke Characterization","authors":"A. Fedeli, A. Randazzo, A. Sciarrone, I. Bisio, F. Lavagetto, M. Pastorino","doi":"10.23919/URSIGASS49373.2020.9232318","DOIUrl":"https://doi.org/10.23919/URSIGASS49373.2020.9232318","url":null,"abstract":"An early diagnosis of brain stroke diseases is crucial to identify the recommended medical treatment in the first hours after the accident. In this contribution, the earlystage characterization of brain strokes is tackled by a microwave imaging technique which exploits the benefits of a combined qualitative/quantitative data inversion. A first qualitative image of the stroke is exploited to build the map of the Lebesgue-space exponent function adopted by the inner solving step of a Newton-type reconstruction approach. Numerical results are presented as an initial assessment of the proposed strategy.","PeriodicalId":438881,"journal":{"name":"2020 XXXIIIrd General Assembly and Scientific Symposium of the International Union of Radio Science","volume":"27 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2020-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121665493","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: 1
On the relationship between C-band interferometric coherence and crop phenology: case study of Metaponto plain (Basilicata, Italy) c波段干涉相干性与作物物候的关系——以意大利巴西利卡塔省Metaponto平原为例
2020 XXXIIIrd General Assembly and Scientific Symposium of the International Union of Radio Science Pub Date : 2020-08-01 DOI: 10.23919/URSIGASS49373.2020.9231984
O. Masci, F. Montesano, G. Nico, V. Cantore
{"title":"On the relationship between C-band interferometric coherence and crop phenology: case study of Metaponto plain (Basilicata, Italy)","authors":"O. Masci, F. Montesano, G. Nico, V. Cantore","doi":"10.23919/URSIGASS49373.2020.9231984","DOIUrl":"https://doi.org/10.23919/URSIGASS49373.2020.9231984","url":null,"abstract":"In this paper we discuss the use of Sentinel-1 interferometric Synthetic Aperture Radar (SAR) coherence to study the crop phenology. This research activity has been proposed within the project “On Demand Services for Smart Agriculture” (ODESSA)”, funded by the European Regional Development Fund (ERDF), Axis I Research and Innovation, Action 1B.1.2.1.","PeriodicalId":438881,"journal":{"name":"2020 XXXIIIrd General Assembly and Scientific Symposium of the International Union of Radio Science","volume":"23 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2020-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121789775","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
High ozone episodes and their association to stratospheric intrusion over Northeast India 高臭氧事件及其与印度东北部平流层入侵的关系
2020 XXXIIIrd General Assembly and Scientific Symposium of the International Union of Radio Science Pub Date : 2020-08-01 DOI: 10.23919/URSIGASS49373.2020.9232180
Chandrakala Bharali, Arshini Saikia, Binita Pathak, P. Bhuyan
{"title":"High ozone episodes and their association to stratospheric intrusion over Northeast India","authors":"Chandrakala Bharali, Arshini Saikia, Binita Pathak, P. Bhuyan","doi":"10.23919/URSIGASS49373.2020.9232180","DOIUrl":"https://doi.org/10.23919/URSIGASS49373.2020.9232180","url":null,"abstract":"Surface ozone measurements in the northern hemisphere till date have found spring maximum. This spring maximum is a combined effect of photochemical production from anthropogenic emissions of precursors and intrusion of stratospheric air with high concentrations of ozone but quantification of contribution from each of these processes is still uncertain. Strong stratospheric intrusion have been observed in the month of April over 25-30 N latitude accompanied by intrusion of ozone rich air into the troposphere. Ground measurements also show higher ozone concentration (> 40 ppb) near the surface. Observation of CO (carbon monoxide) is used to delineate the convective outflow of ozone and its precursors or contribution from biomass burning.","PeriodicalId":438881,"journal":{"name":"2020 XXXIIIrd General Assembly and Scientific Symposium of the International Union of Radio Science","volume":"39 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2020-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124965469","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
Dyadic Green’s Function Studies for the Three-shell Head Model 三壳头模型的并矢格林函数研究
2020 XXXIIIrd General Assembly and Scientific Symposium of the International Union of Radio Science Pub Date : 2020-08-01 DOI: 10.23919/URSIGASS49373.2020.9232296
G. P. Zouros, G. Kolezas, G. Fikioris, N. Tsitsas
{"title":"Dyadic Green’s Function Studies for the Three-shell Head Model","authors":"G. P. Zouros, G. Kolezas, G. Fikioris, N. Tsitsas","doi":"10.23919/URSIGASS49373.2020.9232296","DOIUrl":"https://doi.org/10.23919/URSIGASS49373.2020.9232296","url":null,"abstract":"In this work, we employ analytical expressions for the calculation of the dyadic Green’s function (DGF) of the isotropic three-shell head model, due to an infinitesimal electric dipole located in the internal core that corresponds to the brain. We compute the electric field obtained from this DGF and compare and validate our analytical results with HFSS commercial software when the dipole is inside a single sphere. Then, we numerically examine the behavior of the electric field due to the placement of the dipole inside a three-shell spherical head model. Finally, we discuss how the isotropic model can be extended to the more complicated anisotropic one by considering a volume integral equation approach.","PeriodicalId":438881,"journal":{"name":"2020 XXXIIIrd General Assembly and Scientific Symposium of the International Union of Radio Science","volume":"50 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2020-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116761556","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
Electrode-based implanted HBC channel characterization and SAR analysis 基于电极的植入HBC通道表征和SAR分析
2020 XXXIIIrd General Assembly and Scientific Symposium of the International Union of Radio Science Pub Date : 2020-08-01 DOI: 10.23919/URSIGASS49373.2020.9232390
Q. Wang, X. Du, T. Bauer, M. Bärhold, D. Plettemeier
{"title":"Electrode-based implanted HBC channel characterization and SAR analysis","authors":"Q. Wang, X. Du, T. Bauer, M. Bärhold, D. Plettemeier","doi":"10.23919/URSIGASS49373.2020.9232390","DOIUrl":"https://doi.org/10.23919/URSIGASS49373.2020.9232390","url":null,"abstract":"This summary paper investigates the transmission channel gain and the specific absorption rate (SAR) for implanted HBC based on the galvanic-coupled implantable electrodes, to explore the suitability of human body tissue for a galvanic implanted HBC wireless communication. Based on numerical simulation and phantom measurement, the influence of the electrode length and inter-electrode distance on the channel gain and SAR has been studied. In the HBC frequency range of interest of 5MHz-50MHz, the frequency doesn’t have a noticeable effect on the channel gain. Channel transmission characteristics for different distance have been shown to be similar for different electrode dimensions. With larger transmission distance, the channel gain is decreasing. Larger implanted electrode demonstrates the relative better channel gain as well as lower localized SAR peak.","PeriodicalId":438881,"journal":{"name":"2020 XXXIIIrd General Assembly and Scientific Symposium of the International Union of Radio Science","volume":"11 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2020-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125084682","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
Substrate-Integrated Coaxial Bandpass Filters With Symmetrical Quasi-Absorptive Response 具有对称准吸收响应的基片集成同轴带通滤波器
2020 XXXIIIrd General Assembly and Scientific Symposium of the International Union of Radio Science Pub Date : 2020-08-01 DOI: 10.23919/URSIGASS49373.2020.9232162
D. Psychogiou, R. Gómez‐García
{"title":"Substrate-Integrated Coaxial Bandpass Filters With Symmetrical Quasi-Absorptive Response","authors":"D. Psychogiou, R. Gómez‐García","doi":"10.23919/URSIGASS49373.2020.9232162","DOIUrl":"https://doi.org/10.23919/URSIGASS49373.2020.9232162","url":null,"abstract":"This paper discusses a new class of substrate-integrated coaxial (SIC) resonator-based bandpass filters (BPFs) with symmetrical/two-port quasi-reflectionless behavior and quasi-elliptic-type power transmission response. The proposed quasi-absorptive SIC BPF concept is based on in-series-cascaded two-pole/one-transmission-zero (TZ) BPF modules that are resistively terminated with first-order bandstop filtering sections. High levels of filtering selectivity and low in-band insertion loss are obtained by using high-quality-factor coaxial-cavity resonators and a mixed electromagnetic (EM) inter-resonator coupling. The enabling capabilities of the engineered quasi-absorptive SIC-based BPF concept are discussed through various theoretical examples and the manufacturing and testing of an S-band prototype with the following performance metrics: center frequency of 3.75 GHz, minimum in-band insertion loss equal to 0.75 dB, 3-dB passband bandwidth (BW) of 540 MHz, and 10-dB-referred quasi-reflectionless BW equal to 1.93 GHz.","PeriodicalId":438881,"journal":{"name":"2020 XXXIIIrd General Assembly and Scientific Symposium of the International Union of Radio Science","volume":"9 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2020-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122731257","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: 1
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