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2022 URSI Regional Conference on Radio Science (USRI-RCRS)最新文献

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A Low Cost Ground Station Setup for Introducing Undergraduate Students to Satellite Reception and Radio Astronomy 向大学生介绍卫星接收和射电天文学的低成本地面站装置
2022 URSI Regional Conference on Radio Science (USRI-RCRS) Pub Date : 2022-12-01 DOI: 10.23919/URSI-RCRS56822.2022.10118461
Amit Deokar, Rohan Sanghai, Abhijit Gadekar, Ankit Sharma
{"title":"A Low Cost Ground Station Setup for Introducing Undergraduate Students to Satellite Reception and Radio Astronomy","authors":"Amit Deokar, Rohan Sanghai, Abhijit Gadekar, Ankit Sharma","doi":"10.23919/URSI-RCRS56822.2022.10118461","DOIUrl":"https://doi.org/10.23919/URSI-RCRS56822.2022.10118461","url":null,"abstract":"A satellite ground station, being the only point of contact with satellites, needs to be receptive over a large frequency range. It also has to be efficient enough for clear and continuous data reception. Hence, antennas form an essential part of a ground station. Therefore, we have strategically chosen six specific antennas and analysed them to obtain seamless reception as well as scanning of signals over HF, VHF, UHF, L band, and S band, along with one horn antenna to detect the H I (1420.4 MHz) frequency. The antennas can also receive linear as well as circularly polarised signals. In this paper, we discuss the design of the ground station along with its results with an aim to serve as a succinct reference for beginners in the field.","PeriodicalId":229743,"journal":{"name":"2022 URSI Regional Conference on Radio Science (USRI-RCRS)","volume":"22 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128196030","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
GEO-GEO Radiance Inter-Calibration of INSAT-3D with MSG-SEVIRI and Total Ozone Retrieval using Machine Learning 基于MSG-SEVIRI的INSAT-3D GEO-GEO辐射间定标及基于机器学习的总臭氧检索
2022 URSI Regional Conference on Radio Science (USRI-RCRS) Pub Date : 2022-12-01 DOI: 10.23919/URSI-RCRS56822.2022.10118566
Prajjwal Rawat, M. Naja, P. Thapliyal
{"title":"GEO-GEO Radiance Inter-Calibration of INSAT-3D with MSG-SEVIRI and Total Ozone Retrieval using Machine Learning","authors":"Prajjwal Rawat, M. Naja, P. Thapliyal","doi":"10.23919/URSI-RCRS56822.2022.10118566","DOIUrl":"https://doi.org/10.23919/URSI-RCRS56822.2022.10118566","url":null,"abstract":"Atmospheric ozone has a unique vertical distribution among various trace gases and plays different roles at different altitudes. The useful stratosphere ozone absorbs harmful UV radiations, while tropospheric ozone, a powerful greenhouse gas, adversely affects living beings and vegetation. The continuous monitoring of the total ozone column (TOC) is necessary to understand the various large-scale dynamics, recovery of total ozone over different regions, and accurately estimate the incoming UV flux to the earth's surface. Nowadays, ozone monitoring via satellite-based remote sensing has gained wide importance. The Indian geostationary satellite INSAT-3D is accomplishing this need for India's tropical region. The poor understanding of dominant circulations and limited ground-based observations over tropical regions, like India, ozone recovery, and trend studies remain complex and uncertain, where INSAT-3D has enormous capabilities. However, INSAT-3D has underestimated the total ozone column by more than 22 DU, compared with ozonesonde and OMI. The large TOC bias could be attributed to lower reliability of retrieval and INSAT-3D radiance biases. To mitigate these differences, the radiance biases in INSAT-3D observations are calibrated using the GEO-GEO methodology with MSG-SEVIRI for collocated pixels. It shows biases in INSAT-3D by more than 5 K. These biases of INSAT-3D are corrected to better retrieve the total ozone over the Indian region from INSAT-3D. A well-trained machine learning (ML) model is then used for TOC retrieval, which retrieved TOC effectively and matches well with SEVIRI.","PeriodicalId":229743,"journal":{"name":"2022 URSI Regional Conference on Radio Science (USRI-RCRS)","volume":"13 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128891532","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
Additively Manufactured Metamaterial Luneburg Lens for X-band 用于x波段的增材制造超材料Luneburg透镜
2022 URSI Regional Conference on Radio Science (USRI-RCRS) Pub Date : 2022-12-01 DOI: 10.23919/URSI-RCRS56822.2022.10118562
Nisha Yadav, N. Gupta, S.A. Ramakrishana
{"title":"Additively Manufactured Metamaterial Luneburg Lens for X-band","authors":"Nisha Yadav, N. Gupta, S.A. Ramakrishana","doi":"10.23919/URSI-RCRS56822.2022.10118562","DOIUrl":"https://doi.org/10.23919/URSI-RCRS56822.2022.10118562","url":null,"abstract":"This paper presents the design, simulation and fabrication of metamaterial based Luneburg lens for X-band through additive manufacturing using stereolithography (SLA) technique. SLA offers a fast and cost effective solution for prototyping of dielectric metamaterial structures. It also has better resolution as compared to fused deposition modelling and digital light processing method. A comparison has been drawn between the metamaterial lens and ideal gradient refractive index (GRIN) design for better understanding of lens operation, where it has been found that the non-ideal GRIN profile leads to some performance gaps. The performance of the fabricated structure has been tested at 10 GHz.","PeriodicalId":229743,"journal":{"name":"2022 URSI Regional Conference on Radio Science (USRI-RCRS)","volume":"121 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133474806","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
Triple Band Polarization Independent Ultrathin Metamaterial Microwave Absorber for C and X Band Applications 用于C和X波段的三波段偏振无关超薄超材料微波吸收器
2022 URSI Regional Conference on Radio Science (USRI-RCRS) Pub Date : 2022-12-01 DOI: 10.23919/URSI-RCRS56822.2022.10118517
G. Chaitanya, P. Peshwe, A. Kothari
{"title":"Triple Band Polarization Independent Ultrathin Metamaterial Microwave Absorber for C and X Band Applications","authors":"G. Chaitanya, P. Peshwe, A. Kothari","doi":"10.23919/URSI-RCRS56822.2022.10118517","DOIUrl":"https://doi.org/10.23919/URSI-RCRS56822.2022.10118517","url":null,"abstract":"The proposed model in this paper introduces a triple band polarization independent microwave absorber for C and X band applications. The proposed unit cell design proffers a cyclo-square shaped resonator at the centre surrounded by quarter part of circular ring resonator with different thickness at each corner on metal ground platted dielectric substrate. The proposed design is polarization insensitive, conformal and stable under oblique incident angle for TE and TM polarized wave up to 45°. Ultrathin thickness of $0.0064lambda_{0}$ at the lowest frequency of absorption is reported. The absorption peaks of 95.0%, 96.25% and 95.53% are obtained at 6.01 GHz, 9.55 GHz and 11.65 GHz frequencies of resonance. It demonstrates FWHM bandwidths of 158.5 MHz (5.94 GHz -6.10 GHz) for first band, 261.6 MHz (9.42 GHz - 9.69 GHz) for second band and 296.1 MHz (11.51 GHz -11.81 GHz) for the third band. The surface current distributions for all the three absorption frequencies are analyzed to study the absorption mechanism.","PeriodicalId":229743,"journal":{"name":"2022 URSI Regional Conference on Radio Science (USRI-RCRS)","volume":"44 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131825380","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
Higher Order Mode Generation for Gyrotron Using Fundamental Mode 利用基模产生回旋管的高阶模
2022 URSI Regional Conference on Radio Science (USRI-RCRS) Pub Date : 2022-12-01 DOI: 10.23919/URSI-RCRS56822.2022.10118518
Maniul Haque, K. Parvez
{"title":"Higher Order Mode Generation for Gyrotron Using Fundamental Mode","authors":"Maniul Haque, K. Parvez","doi":"10.23919/URSI-RCRS56822.2022.10118518","DOIUrl":"https://doi.org/10.23919/URSI-RCRS56822.2022.10118518","url":null,"abstract":"The contribution of this paper is to propose a higher order mode generation for gyrotron using fundamental mode. The proposed structure aerates two higher order modes $- text{TE}_{6,2}$ and TE 10,1 because their first kind of Bessel function values is almost equal. The $text{TE}_{6,2}$ mode is very useful for gyrotron amplification, whereas $text{TE}_{10,1}$ is an undesired higher-order mode. We suppressed the TE10,1 mode by properly loading high conductive wire.","PeriodicalId":229743,"journal":{"name":"2022 URSI Regional Conference on Radio Science (USRI-RCRS)","volume":"10 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131462296","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
Remote Transfer of Ultra-Stable Optical Frequency Reference using Active Cancellation of Fiber Induced Phase Noise 利用有源对消光纤诱导相位噪声的超稳定光频参远程传输
2022 URSI Regional Conference on Radio Science (USRI-RCRS) Pub Date : 2022-12-01 DOI: 10.23919/URSI-RCRS56822.2022.10118547
M. Das
{"title":"Remote Transfer of Ultra-Stable Optical Frequency Reference using Active Cancellation of Fiber Induced Phase Noise","authors":"M. Das","doi":"10.23919/URSI-RCRS56822.2022.10118547","DOIUrl":"https://doi.org/10.23919/URSI-RCRS56822.2022.10118547","url":null,"abstract":"Comparison of ultra-stable frequency references located in geographically distributed areas require a transfer technique, which offers stability of 10−17 at 1 s over tens of kilometer. Such remote frequency transfer will allow comparing the optical frequency references of same or different atomic species (through a frequency comb bridge) for test of relativistic geodesy [1] or time variation of fundamental constants [2], and will contribute towards the database of frequency ratio measurements-an essential requirement for the re-definition of the SI second based on optical clocks [3]. It will also facilitate in creating an optical to microwave frequency link that can be used by various SI standards laboratory requiring stable microwave sources. In this paper, I discuss the modulated optical carrier wave based ultra-stable frequency reference transfer technique, and present a study of a laser interferometer based active fiber noise cancellation system and its applications.","PeriodicalId":229743,"journal":{"name":"2022 URSI Regional Conference on Radio Science (USRI-RCRS)","volume":"35 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132161215","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
Characteristics of Equatorial F-region Irregularities along the 90°E Meridian during High Solar Activity Phase 太阳活动高峰期沿90°E子午线赤道f区不规则特征
2022 URSI Regional Conference on Radio Science (USRI-RCRS) Pub Date : 2022-12-01 DOI: 10.23919/URSI-RCRS56822.2022.10118463
Siva Sai Kumar Rajana, S. Panda, S. Jade
{"title":"Characteristics of Equatorial F-region Irregularities along the 90°E Meridian during High Solar Activity Phase","authors":"Siva Sai Kumar Rajana, S. Panda, S. Jade","doi":"10.23919/URSI-RCRS56822.2022.10118463","DOIUrl":"https://doi.org/10.23919/URSI-RCRS56822.2022.10118463","url":null,"abstract":"This study investigated the characteristics of the Equatorial ionospheric F-region Irregularities (EFIs) along the 90°E meridian using the phase fluctuations of Global Navigational Satellite System (GNSS) signals during the maximum phase of solar activity in the solar cycle 24. Results indicate that the occurrence of EFIs is related to the local time, season and magnetic latitude. The EFIs are usually observed during the post-sunset hours and are more pronounced before midnight. In the equinox seasons, EFIs are more common and intense around the magnetic equator and low latitude regions. The disappearance time of EFIs is late during the spring equinox season than the autumn equinox. The occurrence probability of severe EFIs is high in the equinox seasons than in the solstice seasons, especially in spring equinox. Moderate EFIs are observed more in the spring equinox season over the pole-ward edge of the Equatorial Ionization Anomaly (EIA) region in both the hemispheres. This study helps in understanding the spatio-temporal characteristics of EFIs and thereby mitigating the scintillation effects in highly precise and dynamic applications of satellite-based navigation systems over the equatorial and low latitude Indian sector.","PeriodicalId":229743,"journal":{"name":"2022 URSI Regional Conference on Radio Science (USRI-RCRS)","volume":"57 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114064983","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
Ground and Volume Scattering Separation in Compact Polarimentric Interferometric SAR Data 紧凑偏振心干涉SAR数据的地面和体散射分离
2022 URSI Regional Conference on Radio Science (USRI-RCRS) Pub Date : 2022-12-01 DOI: 10.23919/URSI-RCRS56822.2022.10118450
S. Dey, Narayanarao Bhogapurapu, A. Bhattacharya
{"title":"Ground and Volume Scattering Separation in Compact Polarimentric Interferometric SAR Data","authors":"S. Dey, Narayanarao Bhogapurapu, A. Bhattacharya","doi":"10.23919/URSI-RCRS56822.2022.10118450","DOIUrl":"https://doi.org/10.23919/URSI-RCRS56822.2022.10118450","url":null,"abstract":"This work presents a methodology to separate the ground and volume contributions from compact polarimetric SAR interferometric (PolInSAR) data over forest areas. One can decompose the PolInSAR data into two covariance matrices from ground and volume in a particular resolution cell, relying on the assumptions of the two-layer model. We demonstrate this approach using simulated single baseline compact polarimetric SAR data of the BioSAR-2008 mission over boreal forests in Northern Sweden.","PeriodicalId":229743,"journal":{"name":"2022 URSI Regional Conference on Radio Science (USRI-RCRS)","volume":"15 6 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123667528","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
Real-world Shelf-Life Study of Tissue Equivalent Liquids for SAR evaluation 用于SAR评估的组织等效液体的实际保质期研究
2022 URSI Regional Conference on Radio Science (USRI-RCRS) Pub Date : 2022-12-01 DOI: 10.23919/URSI-RCRS56822.2022.10118551
A. Sharma, S. Dubey
{"title":"Real-world Shelf-Life Study of Tissue Equivalent Liquids for SAR evaluation","authors":"A. Sharma, S. Dubey","doi":"10.23919/URSI-RCRS56822.2022.10118551","DOIUrl":"https://doi.org/10.23919/URSI-RCRS56822.2022.10118551","url":null,"abstract":"SAR assessment, as defined by the IEEE-1528 standard, has been the standard for defining the safe exposure of the RF radiations and usage limits for wireless devices. The Tissue Equivalent Liquids (TELs) are essential parts of the SAR assessment system, as they mimic the human body's dielectric properties at their specific frequencies and allow for testing of the range of the wireless devices as per specified procedures. Since, the TELs are artificially synthesized compositions, they also need to meet the regulatory requirements of labelling the product and undergo shelf-life assessment for estimating the usable product life. In this paper, we present the real-world shelf-life study of few TEL compositions of different frequency range. The dielectric properties of these TELs at their respective frequency values/range are assessed and compared for over a period of 18 months, at different intervals, while keeping the TELs stored as per IEEE specified storage conditions i.e. temperature between 18°C and 25°C (within $pm 1 {{}^{circ}mathrm{C}}$) with RH between 40%-60%.","PeriodicalId":229743,"journal":{"name":"2022 URSI Regional Conference on Radio Science (USRI-RCRS)","volume":"14 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123716684","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
Evaluation of different Machine Learning Models for identifications of Flares with CMEs 不同机器学习模型对日冕物质抛射耀斑识别的评估
2022 URSI Regional Conference on Radio Science (USRI-RCRS) Pub Date : 2022-12-01 DOI: 10.23919/URSI-RCRS56822.2022.10118488
Hemapriya Raju, Saurabh Das
{"title":"Evaluation of different Machine Learning Models for identifications of Flares with CMEs","authors":"Hemapriya Raju, Saurabh Das","doi":"10.23919/URSI-RCRS56822.2022.10118488","DOIUrl":"https://doi.org/10.23919/URSI-RCRS56822.2022.10118488","url":null,"abstract":"Solar eruptions such as CMEs and flares causes geomagnetic and communication disturbances on Earth. CMEs can be found in conjunction with flares, filaments, or independent. Although both flares and CMEs are understood as triggered by a common physical process magnetic reconnection, yet, the degree of association among them is unknown. We attempted to model the association of CMEs with flares through extensive Machine Learning models to study the occurrence of CMEs. Further, to improve the class separability, we have utilized the parameter change information obtained from the respective subsequent time difference. Since there is significant imbalance between the classes, we had explored approaches such as under sampling majority class, oversampling minority class and synthetically generated minority samples through SMOTE Technique. We achieved TSS around 0.81 without adding change information, and TSS around 0.92 after adding change information as additional feature on prediction of CMEs associated with flares for LDA, after addressing the class imbalance issues.","PeriodicalId":229743,"journal":{"name":"2022 URSI Regional Conference on Radio Science (USRI-RCRS)","volume":"12 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127003029","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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