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2021 XXXIVth General Assembly and Scientific Symposium of the International Union of Radio Science (URSI GASS)最新文献

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Wideband Interference Mitigation for SAR Based on Intrinsic Chirp Component Decomposition 基于内禀啁啾分量分解的SAR宽带干扰抑制
2021 XXXIVth General Assembly and Scientific Symposium of the International Union of Radio Science (URSI GASS) Pub Date : 2021-08-28 DOI: 10.23919/URSIGASS51995.2021.9560369
Wenchang Han, Shiguo Mei, Weiwei Fan, Tian Tian, Feng Zhou
{"title":"Wideband Interference Mitigation for SAR Based on Intrinsic Chirp Component Decomposition","authors":"Wenchang Han, Shiguo Mei, Weiwei Fan, Tian Tian, Feng Zhou","doi":"10.23919/URSIGASS51995.2021.9560369","DOIUrl":"https://doi.org/10.23919/URSIGASS51995.2021.9560369","url":null,"abstract":"The wideband interferences (WBIs) seriously degrade the quality of the synthetic aperture radar (SAR) image. Since the WBI occupies a larger bandwidth, it is difficult to mitigate it. Some existing WBI mitigation methods based on transform-domain analysis or filter design suffer from model mismatch and signal loss. In order to solve this problem, a method based on instantaneous frequency (IF) estimation and intrinsic chirp component decomposition (ICCD) is proposed to suppress WBI in this paper. First, a WBI-contaminated SAR echo is represented in the time-frequency domain by using the short-time Fourier transform (STFT). Then, the IF estimation is carried out for the WBI components. Finally, the WBI is extracted by using the ICCD. The experimental results verify the effectiveness of the proposed method.","PeriodicalId":152047,"journal":{"name":"2021 XXXIVth General Assembly and Scientific Symposium of the International Union of Radio Science (URSI GASS)","volume":"47 4","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-08-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114020275","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
HF Pulsed Thundercloud Emission Observed in the Upper Volga Region of Russia 俄罗斯伏尔加河上游地区观测到的高频脉冲雷云发射
2021 XXXIVth General Assembly and Scientific Symposium of the International Union of Radio Science (URSI GASS) Pub Date : 2021-08-28 DOI: 10.23919/URSIGASS51995.2021.9560396
A. Karashtin, Yu. V. Shlyugaev, Olga S. Karashtina
{"title":"HF Pulsed Thundercloud Emission Observed in the Upper Volga Region of Russia","authors":"A. Karashtin, Yu. V. Shlyugaev, Olga S. Karashtina","doi":"10.23919/URSIGASS51995.2021.9560396","DOIUrl":"https://doi.org/10.23919/URSIGASS51995.2021.9560396","url":null,"abstract":"Radio frequency emission from thunderclouds is analysed on the base of measurements over a wide frequency range with a high temporal resolution. This emission mainly consists of short sub-microsecond bi-polar pulses. Characteristics of the pulses are studied at different stages of lightning discharge development as well as for events does not leading to lightning.","PeriodicalId":152047,"journal":{"name":"2021 XXXIVth General Assembly and Scientific Symposium of the International Union of Radio Science (URSI GASS)","volume":"7 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-08-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124347485","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
Initial investigation on different types of clouds observed by Mars Color Camera (MCC) from India's first Mars Orbiter Mission (MOM) 印度第一次火星轨道飞行器(MOM)火星彩色相机(MCC)观测到的不同类型云的初步研究
2021 XXXIVth General Assembly and Scientific Symposium of the International Union of Radio Science (URSI GASS) Pub Date : 2021-08-28 DOI: 10.23919/URSIGASS51995.2021.9560281
J. Kalita, A. Guha
{"title":"Initial investigation on different types of clouds observed by Mars Color Camera (MCC) from India's first Mars Orbiter Mission (MOM)","authors":"J. Kalita, A. Guha","doi":"10.23919/URSIGASS51995.2021.9560281","DOIUrl":"https://doi.org/10.23919/URSIGASS51995.2021.9560281","url":null,"abstract":"In the present work, we analyzed different types of clouds observed at the limb as well as over the surface of the red planet by MCC and estimated the atmospheric parameter associated with it. Our analysis based on the data collected by Mars Colour Camera (MCC) on board Indian Mars Orbiter Mission during orbit number 44,45,48,49, 50,51,179,187,190,191,466 and 474. Estimated height of the high altitude cloud varies from 40 to 76 km and horizontal spreading of 400 to 1100 km. We used ARC-GIS to detect the area over which the high altitude clouds are observed. These detached layers of clouds are found to be formed of Dust and water-ice particle. MRO-MCS and MARCI confirms few dust events during the appearance of the high altitude cloud. Lee-wave cloud images are captured during the MY33 and MY34. Estimated wavelength of the Lee wave cloud varies from 38 to 44 km while wind speed varies from 54 to 64 m/sec. Aerosol Optical Depth (AOD) as a function of altitude varies from 0.6 to 2.4 for red channel and 0.8 to 1.8 for blue channel for the captured events. We consulted Global Circulation Model (GCM) as well as MOLA-DEM to frame the AOD output. Estimated wind speed profile from MCC and MARCI-MGDM suggested the circulation of strong wind across the globe and delivered input to formation of clouds through different processes related to the atmosphere dynamics viz. Deep Convection, Orographic lift, Thermal updraft, etc. In our present study we tried to estimate the parameter related to these processes and tried to correlate them with the observed events.","PeriodicalId":152047,"journal":{"name":"2021 XXXIVth General Assembly and Scientific Symposium of the International Union of Radio Science (URSI GASS)","volume":"35 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-08-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127669786","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
Non-Uniform sampling in near field measurement: Experimental results 近场测量中的非均匀采样:实验结果
2021 XXXIVth General Assembly and Scientific Symposium of the International Union of Radio Science (URSI GASS) Pub Date : 2021-08-28 DOI: 10.23919/URSIGASS51995.2021.9560603
M. A. Maisto, R. Solimene, G. Leone, R. Pierri
{"title":"Non-Uniform sampling in near field measurement: Experimental results","authors":"M. A. Maisto, R. Solimene, G. Leone, R. Pierri","doi":"10.23919/URSIGASS51995.2021.9560603","DOIUrl":"https://doi.org/10.23919/URSIGASS51995.2021.9560603","url":null,"abstract":"In this paper, the problem of sampling the field radiated by a planar source observed over a finite planar aperture located in the near-field is addressed. In particular, the paper is devoted to assess the performance of the sampling strategy proposed in [9] in a real environment. Accordingly, such a strategy is compared to the classical half-wavelength sampling approach by processing some experimental data. It is shown that in spite of the resulting sampling points are much lower than the ones required by the half-wavelength sampling, the proposed strategy allows to obtain good results.","PeriodicalId":152047,"journal":{"name":"2021 XXXIVth General Assembly and Scientific Symposium of the International Union of Radio Science (URSI GASS)","volume":"17 16 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-08-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125615137","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
Ionosphere-thermosphere coupling during the 22–23 June 2015 geomagnetic storm: Swarm and FPI coordinated observations above the Oukaimeden observatory 2015年6月22-23日地磁风暴期间的电离层-热层耦合:Swarm和FPI在Oukaimeden天文台上方的协调观测
2021 XXXIVth General Assembly and Scientific Symposium of the International Union of Radio Science (URSI GASS) Pub Date : 2021-08-28 DOI: 10.23919/URSIGASS51995.2021.9560388
F. Pitout, A. Loutfi, A. Bounhir, S. Buchert, Z. Benkhaldoun, J. Makela
{"title":"Ionosphere-thermosphere coupling during the 22–23 June 2015 geomagnetic storm: Swarm and FPI coordinated observations above the Oukaimeden observatory","authors":"F. Pitout, A. Loutfi, A. Bounhir, S. Buchert, Z. Benkhaldoun, J. Makela","doi":"10.23919/URSIGASS51995.2021.9560388","DOIUrl":"https://doi.org/10.23919/URSIGASS51995.2021.9560388","url":null,"abstract":"We investigate the response of the ionosphere-thermosphere coupled system to the 22-23 June 2015 geomagnetic storm in the region above the Oukaimeden observatory in Morocco with a Fabry-Perot interferometer and the Swarm satellites. The measured thermospheric neutral winds are strong enough to have two direct consequences. First, they create a strong asymmetry in the equatorial ionisation crests on both sides of the magnetic equator (actually, they make the southern hemisphere crest disappear). This asymmetry is explained by the southerly thermospheric neutral wind that was blowing during the storm and is shown to be favoured by the season. Second, within the northern hemisphere ionisation crest, Swarm A and C detect km-size electron density structures. Those may be ascribed to gradient drift instability.","PeriodicalId":152047,"journal":{"name":"2021 XXXIVth General Assembly and Scientific Symposium of the International Union of Radio Science (URSI GASS)","volume":"3 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-08-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125724229","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
Age Dependence of Human Exposure in Emerging 5G Bands: Comparison between Plane-Wave Exposure and Multi-Beam Antennas 5G新兴频段人体暴露的年龄依赖性:平面波暴露与多波束天线的比较
2021 XXXIVth General Assembly and Scientific Symposium of the International Union of Radio Science (URSI GASS) Pub Date : 2021-08-28 DOI: 10.23919/URSIGASS51995.2021.9560230
G. Sacco, D. Nikolavev, R. Sauleau, M. Zhadobov
{"title":"Age Dependence of Human Exposure in Emerging 5G Bands: Comparison between Plane-Wave Exposure and Multi-Beam Antennas","authors":"G. Sacco, D. Nikolavev, R. Sauleau, M. Zhadobov","doi":"10.23919/URSIGASS51995.2021.9560230","DOIUrl":"https://doi.org/10.23919/URSIGASS51995.2021.9560230","url":null,"abstract":"The fast development of the 5th generation (5G) mobile networks and human-centered communications is leading to the increasing proliferation of wireless devices resulting in ubiquitous exposure of people of all ages. This study investigates the effect of ageing on the power deposition at 26 GHz and 60 GHz, frequencies upcoming for 5/6G. The exposure under near-field conditions induced by multibeam radiating structures is compared to the one induced by a plane wave. The highest variation of the averaged absorbed power density with respect to the typical value for adults is observed at 70 years and corresponds to 8.8% at 26 GHz and 6.9% at 60 GHz. The maximum decrease is obtained for children at 5 years and is of -4.5% at 26 GHz and -3.7% at 60 GHz. At 26 GHz, the plane-wave model results in an underestimation of the averaged power density variations obtained with a multi-beam antenna, while at 60 GHz the variations with the two sources of exposures are almost identical.","PeriodicalId":152047,"journal":{"name":"2021 XXXIVth General Assembly and Scientific Symposium of the International Union of Radio Science (URSI GASS)","volume":"68 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-08-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125752258","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
A Novel Detector for SETI on Radio Telescope Arrays 一种新型射电望远镜阵列SETI探测器
2021 XXXIVth General Assembly and Scientific Symposium of the International Union of Radio Science (URSI GASS) Pub Date : 2021-08-28 DOI: 10.23919/URSIGASS51995.2021.9560628
K. Houston
{"title":"A Novel Detector for SETI on Radio Telescope Arrays","authors":"K. Houston","doi":"10.23919/URSIGASS51995.2021.9560628","DOIUrl":"https://doi.org/10.23919/URSIGASS51995.2021.9560628","url":null,"abstract":"The advent of SETI detection processing on interferometric telescopes presents challenges for signal processing. Beamforming the outputs of many dishes or aperture arrays is particularly difficult, requiring a very large number of beams to fill the primary field of view (FOV). Meanwhile the array gain is limited because of array sparseness. Incoherent beamforming (IBF) is the conventional alternative. IBF covers the primary FOV at a relatively low computational cost but has limited sensitivity. In this paper, an alternative to beamforming based on the observed covariance matrix is proposed. A method called Covariance Off-Diagonal Sum (CODS) computes the root-mean-square of the covariance matrix elements above the main diagonal, and is found to offer 3 dB (2x) improved sensitivity over IBF while still covering the primary FOV. The computational cost is approximately $N_{AP}/2$ times that of IBF, where $N_{AP}$ is the number of apertures (dishes or aperture array stations), but could be orders of magnitude below beamforming over the full FOV. An Eigenvalue detector is also considered. We hypothesize that CODS will be less sensitive to RFI compared to IBF. The utility of CODS is not limited to narrowband signals in SETI, but could be useful for rapid detection of pulsars and fast radio bursts as well.","PeriodicalId":152047,"journal":{"name":"2021 XXXIVth General Assembly and Scientific Symposium of the International Union of Radio Science (URSI GASS)","volume":"13 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-08-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121722351","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: 2
The UAPO Solution for the Plane Wave Diffraction by a Resistive Half-Plane in the Case of Skew Incidence 斜入射情况下电阻半平面平面波衍射的UAPO解
2021 XXXIVth General Assembly and Scientific Symposium of the International Union of Radio Science (URSI GASS) Pub Date : 2021-08-28 DOI: 10.23919/URSIGASS51995.2021.9560431
G. Riccio, G. Gennarelli, F. Ferrara, C. Gennarelli, R. Guerriero
{"title":"The UAPO Solution for the Plane Wave Diffraction by a Resistive Half-Plane in the Case of Skew Incidence","authors":"G. Riccio, G. Gennarelli, F. Ferrara, C. Gennarelli, R. Guerriero","doi":"10.23919/URSIGASS51995.2021.9560431","DOIUrl":"https://doi.org/10.23919/URSIGASS51995.2021.9560431","url":null,"abstract":"The extension of the Uniform Asymptotic Physical Optics approach to the three-dimensional diffraction problem involving a resistive half-plane is presented in this work. The resistive boundary conditions in correspondence of the screen are used to determine the reflection and transmission coefficients for both the polarizations and then the Geometrical Optics field around the structure. This enables the formulation of the electric and magnetic equivalent surface currents to be considered as radiating sources in the approach for the evaluation of the diffracted field. The ability of this contribution to compensate the jumps of the Geometrical Optics field is proved by means of numerical tests.","PeriodicalId":152047,"journal":{"name":"2021 XXXIVth General Assembly and Scientific Symposium of the International Union of Radio Science (URSI GASS)","volume":"52 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-08-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121785487","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: 3
A Gain Enhanced Metasurface based Monopole Antenna for WLAN Application 一种用于WLAN的增益增强超表面单极天线
2021 XXXIVth General Assembly and Scientific Symposium of the International Union of Radio Science (URSI GASS) Pub Date : 2021-08-28 DOI: 10.23919/URSIGASS51995.2021.9560426
Diptiranjan Samantaray, Somak Bhattacharyya
{"title":"A Gain Enhanced Metasurface based Monopole Antenna for WLAN Application","authors":"Diptiranjan Samantaray, Somak Bhattacharyya","doi":"10.23919/URSIGASS51995.2021.9560426","DOIUrl":"https://doi.org/10.23919/URSIGASS51995.2021.9560426","url":null,"abstract":"The design and performance of a highly directive gain enhanced metasurface antenna (MSA) has been reported in this paper. The MSA is formed by incorporating the T-shaped patch with $3times 5$ order metasurface (MS) in which the MS is associated with annular hexagonal shaped patches arranging in periodic manner. This antenna operates at 4.99 GHz and the −10 dB impedance bandwidth has been achieved in the range 4.79 GHz-5.09 GHz. The antenna provides the maximum realized gain of 11.2 dBi at 4.99 GHz. The endfire radiation pattern has been observed along E-plane while nearly omnidirectional pattern has been realized along H-plane. The designed structure can be promoted for WLAN applications.","PeriodicalId":152047,"journal":{"name":"2021 XXXIVth General Assembly and Scientific Symposium of the International Union of Radio Science (URSI GASS)","volume":"219 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-08-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131930030","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
MISO Measurements in Indoor Environments at 25 GHz 25 GHz室内环境MISO测量
2021 XXXIVth General Assembly and Scientific Symposium of the International Union of Radio Science (URSI GASS) Pub Date : 2021-08-28 DOI: 10.23919/URSIGASS51995.2021.9560497
Mohamed Abdulali, Amar Al-jzari, S. Salous
{"title":"MISO Measurements in Indoor Environments at 25 GHz","authors":"Mohamed Abdulali, Amar Al-jzari, S. Salous","doi":"10.23919/URSIGASS51995.2021.9560497","DOIUrl":"https://doi.org/10.23919/URSIGASS51995.2021.9560497","url":null,"abstract":"This paper presents the results of parameter measurements in two indoor environments for both line of sight (LoS) and non-line of sight (NLoS) scenarios at 25 GHz using multiple directional antennae at the transmitter and a single omnidirectional antenna at the receiver (MISO) with the custom-designed channel sounder developed at Durham University. The data are analysed to estimate the K-factor, path loss parameters and root mean square (RMS) delay spread for each scenario. The 50% and 90% values of the RMS delay spread values for a 20 dB threshold are presented for both scenarios.","PeriodicalId":152047,"journal":{"name":"2021 XXXIVth General Assembly and Scientific Symposium of the International Union of Radio Science (URSI GASS)","volume":"26 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-08-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132053231","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
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