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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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Seasonal Variation of the D-Region Ionosphere Modelled using Machine Learning Based VLF Remote Sensing 基于机器学习的VLF遥感模拟d区电离层季节变化
2021 XXXIVth General Assembly and Scientific Symposium of the International Union of Radio Science (URSI GASS) Pub Date : 2021-08-28 DOI: 10.23919/URSIGASS51995.2021.9560272
D. Richardson, M. Cohen
{"title":"Seasonal Variation of the D-Region Ionosphere Modelled using Machine Learning Based VLF Remote Sensing","authors":"D. Richardson, M. Cohen","doi":"10.23919/URSIGASS51995.2021.9560272","DOIUrl":"https://doi.org/10.23919/URSIGASS51995.2021.9560272","url":null,"abstract":"This work improves upon a previously developed neural network modelling process that predicted waveguide parameters for the D-region ionosphere on two days [1]. The previous model was limited by manually determining the ideal set of transmitters (Tx) and receivers (Rx) and by computation time. An automatic quality assessment tool was developed to automatically evaluate the optimal network for each day [2]. We also obtained a 14x improvement in model training time by leveraging GPUs and improving the parallelization of the training process. These advancements allowed us to model 328 days across up to 21 paths. With this larger sample size, we show the model is capable of following expected seasonal trends. The model has also been adapted to be used with nighttime data, and is showing promising early results.","PeriodicalId":152047,"journal":{"name":"2021 XXXIVth General Assembly and Scientific Symposium of the International Union of Radio Science (URSI GASS)","volume":"53 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":"126082728","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
Ray-tube integration in shooting and bouncing ray method revisited 再谈射线管与弹跳射线法的整合
2021 XXXIVth General Assembly and Scientific Symposium of the International Union of Radio Science (URSI GASS) Pub Date : 2021-08-28 DOI: 10.23919/URSIGASS51995.2021.9560549
S. Poulsen
{"title":"Ray-tube integration in shooting and bouncing ray method revisited","authors":"S. Poulsen","doi":"10.23919/URSIGASS51995.2021.9560549","DOIUrl":"https://doi.org/10.23919/URSIGASS51995.2021.9560549","url":null,"abstract":"The method of shooting and bouncing rays (SBR) was originally developed for radar cross section (RCS) analysis of aircraft engines, but is today widely used in many applications requiring high-frequency approximations. A dense grid of ray-tubes are launched from the source and traced by the laws of geometrical optics (GO) until they reach a defined exit aperture, from which the far field contribution of the ray-tube is obtained by surface integration. Two alternatives have been suggested on where to perform the surface integration, namely (1) on the ray-tube cross-section or (2) on the exit aperture. The first option is convenient as the electrical field is assumed constant in the ray-tube surface and has been suggested for complex scattering problems. In this paper, it is demonstrated that the surface integration over the ray-tube area can cause a ripple anomaly. It is illustrated that the ripple is caused by omitting parts of the integration surface from which there are no power flow. It is concluded that exit aperture integration should be selected in SBR analysis.","PeriodicalId":152047,"journal":{"name":"2021 XXXIVth General Assembly and Scientific Symposium of the International Union of Radio Science (URSI GASS)","volume":"28 2","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-08-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114125581","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
Diurnal observation of the deep convective precipitation system and the associated gravity wave signatures using 206.5 MHz VHF radar over the central Himalayas 206.5 MHz VHF雷达对喜马拉雅中部地区深对流降水系统及其重力波特征的日观测
2021 XXXIVth General Assembly and Scientific Symposium of the International Union of Radio Science (URSI GASS) Pub Date : 2021-08-28 DOI: 10.23919/URSIGASS51995.2021.9560417
A. Jaiswal, M. Naja, S. Bhattacharjee
{"title":"Diurnal observation of the deep convective precipitation system and the associated gravity wave signatures using 206.5 MHz VHF radar over the central Himalayas","authors":"A. Jaiswal, M. Naja, S. Bhattacharjee","doi":"10.23919/URSIGASS51995.2021.9560417","DOIUrl":"https://doi.org/10.23919/URSIGASS51995.2021.9560417","url":null,"abstract":"With the aim to explore the dynamical behavior of the lower atmosphere during precipitation in monsoon season over Himalayan region, diurnal observation with ARIES Stratosphere Troposphere radar were conducted from September 23 to 24, 2020. Development and evolution of the precipitation system was studied through the derived high resolution wind profiles from radar as well as from radar backscattered power and spectral width. A burst of gravity wave of 8 −10 minutes in period was detected before the precipitation in the mid-troposphere. Similarly gravity waves signatures of 25 minute period were detected among the updraft and downdraft couplet in the upper troposphere and lower stratosphere region during convective precipitation. Overall depletion of turbulent echo power is detected and significant reduction of about 6 dB in radar SNR in noticed around tropopause height during convection. Significant enhancement of horizontal momentum flux noticed during convection period at all height levels.","PeriodicalId":152047,"journal":{"name":"2021 XXXIVth General Assembly and Scientific Symposium of the International Union of Radio Science (URSI GASS)","volume":"2 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":"121223518","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 Ka-band Compact Single-Layer Gap Waveguide Monopulse Slot Array Antenna 一种ka波段紧凑型单层缝隙波导单脉冲缝隙阵列天线
2021 XXXIVth General Assembly and Scientific Symposium of the International Union of Radio Science (URSI GASS) Pub Date : 2021-08-28 DOI: 10.23919/URSIGASS51995.2021.9560590
Miguel Ferrando-Rocher, Bryan Mayor, S. Marini, A. Valero-Nogueira, Jose I. Herranz-Herruzo
{"title":"A Ka-band Compact Single-Layer Gap Waveguide Monopulse Slot Array Antenna","authors":"Miguel Ferrando-Rocher, Bryan Mayor, S. Marini, A. Valero-Nogueira, Jose I. Herranz-Herruzo","doi":"10.23919/URSIGASS51995.2021.9560590","DOIUrl":"https://doi.org/10.23919/URSIGASS51995.2021.9560590","url":null,"abstract":"This paper presents a gap-waveguide-based compact monopulse array antenna for millimeter-wave tracking applications at Ka-band (27.5 to 30.5 GHz). A low-loss Magic-Tee is designed to be used in a monopulse comparator network. The gap waveguide planar monopulse comparator network is integrated in a single layer with a 2 × 2 corporate-fed network combining ridge gap and groove gap waveguides. Simulated results show bandwidths of 10% with input reflection coefficients better than −12 dB for the sum and difference ports over the frequency band of interest. Besides, the isolation between sum and difference ports is more than 50 dB. The simplicity of the design and the fact that it is housed in a single layer permit easy scaling to larger arrays.","PeriodicalId":152047,"journal":{"name":"2021 XXXIVth General Assembly and Scientific Symposium of the International Union of Radio Science (URSI GASS)","volume":"64 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":"125200134","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
Polynomial chaos within the frame of non-destructive testing 无损检测框架内的多项式混沌
2021 XXXIVth General Assembly and Scientific Symposium of the International Union of Radio Science (URSI GASS) Pub Date : 2021-08-28 DOI: 10.23919/URSIGASS51995.2021.9560651
Charles Boulitrop, M. Lambert, S. Bilicz
{"title":"Polynomial chaos within the frame of non-destructive testing","authors":"Charles Boulitrop, M. Lambert, S. Bilicz","doi":"10.23919/URSIGASS51995.2021.9560651","DOIUrl":"https://doi.org/10.23919/URSIGASS51995.2021.9560651","url":null,"abstract":"Inverse scattering problems can be seen as an optimization problem in which a cost function has to be minimized. The cost function measures the discrepancy between a physical model written as a function of the sought parameters and the measured data. Due to the high computational cost of physical models, metamodels (also known as surrogate models) have gradually appeared as alternatives. Polynomial chaos (PC) expansions are a type of metamodel based on an explicit spectral decomposition of the physical model, allowing for an exact computation of the gradient of the metamodel. The gradient of the metamodel is then used to improve the performance of the global algorithm Particle Swarm Optimization (PSO).","PeriodicalId":152047,"journal":{"name":"2021 XXXIVth General Assembly and Scientific Symposium of the International Union of Radio Science (URSI GASS)","volume":"12 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":"125305772","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
Strategies for Synergistic Use of Microwave and Ultrasound Data For Biomedical Imaging
2021 XXXIVth General Assembly and Scientific Symposium of the International Union of Radio Science (URSI GASS) Pub Date : 2021-08-28 DOI: 10.23919/URSIGASS51995.2021.9560554
P. Mojabi, Nozhan Bayat, P. Mojabi, J. Lovetri
{"title":"Strategies for Synergistic Use of Microwave and Ultrasound Data For Biomedical Imaging","authors":"P. Mojabi, Nozhan Bayat, P. Mojabi, J. Lovetri","doi":"10.23919/URSIGASS51995.2021.9560554","DOIUrl":"https://doi.org/10.23919/URSIGASS51995.2021.9560554","url":null,"abstract":"Different strategies are discussed to synergistically use ultrasound and microwave scattering data to improve image specificity and sensitivity. In particular, we consider methods based on machine learning, statistical measures, regularization, and inhomogeneous background approaches to yield a final image using multimodal ultrasound-microwave imaging.","PeriodicalId":152047,"journal":{"name":"2021 XXXIVth General Assembly and Scientific Symposium of the International Union of Radio Science (URSI GASS)","volume":"27 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":"125112683","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
Machine Learning for QoE Management in Future Wireless Networks 未来无线网络QoE管理的机器学习
2021 XXXIVth General Assembly and Scientific Symposium of the International Union of Radio Science (URSI GASS) Pub Date : 2021-08-28 DOI: 10.23919/URSIGASS51995.2021.9560226
Georgios Kougioumtzidis, V. Poulkov, Z. Zaharis, P. Lazaridis
{"title":"Machine Learning for QoE Management in Future Wireless Networks","authors":"Georgios Kougioumtzidis, V. Poulkov, Z. Zaharis, P. Lazaridis","doi":"10.23919/URSIGASS51995.2021.9560226","DOIUrl":"https://doi.org/10.23919/URSIGASS51995.2021.9560226","url":null,"abstract":"The growth in volume and heterogeneity of accessible services in future wireless networks (FWNs), imposes pressure to communication service providers (CSPs) to expand their capacity for network performance monitoring and evaluation, in particular in terms of the performance as it is perceived by end-users. The quality of experience (QoE)-aware design model allows to understand and analyze the operation of networks and services from the end-user's perspective. In addition, network measurements based on QoE constitute a key source of knowledge for the overall functionality and management of the network. In this respect, the implementation of artificial intelligence (AI) and machine learning (ML) in QoE management, increases the accuracy of modeling procedures, improves the monitoring process efficiency, and develops innovative optimization and control methodologies.","PeriodicalId":152047,"journal":{"name":"2021 XXXIVth General Assembly and Scientific Symposium of the International Union of Radio Science (URSI GASS)","volume":"32 18","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-08-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"113984264","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
Analysis of the Susceptibility of the LoRa Communication Protocol in the Railway Electromagnetic Environment 铁路电磁环境下LoRa通信协议的敏感性分析
2021 XXXIVth General Assembly and Scientific Symposium of the International Union of Radio Science (URSI GASS) Pub Date : 2021-08-28 DOI: 10.23919/URSIGASS51995.2021.9560220
V. Deniau, Thomas Vantrovs, Norbert Becuwe, C. Gransart, A. N. de São José, A. Boé, E. Simon, Olivier Vlamynck, Florent Valenti, Jonathan Villain, Quentin Rivette
{"title":"Analysis of the Susceptibility of the LoRa Communication Protocol in the Railway Electromagnetic Environment","authors":"V. Deniau, Thomas Vantrovs, Norbert Becuwe, C. Gransart, A. N. de São José, A. Boé, E. Simon, Olivier Vlamynck, Florent Valenti, Jonathan Villain, Quentin Rivette","doi":"10.23919/URSIGASS51995.2021.9560220","DOIUrl":"https://doi.org/10.23919/URSIGASS51995.2021.9560220","url":null,"abstract":"In the context of the digital transformation of railway transportation systems, railway operators investigate the potentialities of the IoT (Internet of Things) in order to optimize the maintenance operations on the vehicles and the infrastructures. One of the interest is to use IoT communication solutions in order to centralize the data measured by the different sensors distributed everywhere along the railway infrastructures and on board the trains. In this perspective, different communication protocols could be employed. This paper deals specifically with the LoRa communication protocol and analyses its susceptibility in the presence of railway electromagnetic interferences. This paper presents a susceptibility analysis of the LoRa communications in the presence of transient EM interferences representative of the electromagnetic interferences produced by the sliding catenary-pantograph contact.","PeriodicalId":152047,"journal":{"name":"2021 XXXIVth General Assembly and Scientific Symposium of the International Union of Radio Science (URSI GASS)","volume":"146 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":"122609162","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 Partial Computation Offloading Strategy for Microcell-femtolet based Future Generation Edge-Cloud Network 基于微蜂窝基站的下一代边缘云网络部分计算卸载策略
2021 XXXIVth General Assembly and Scientific Symposium of the International Union of Radio Science (URSI GASS) Pub Date : 2021-08-28 DOI: 10.23919/URSIGASS51995.2021.9560190
Anwesha Mukherjee
{"title":"A Partial Computation Offloading Strategy for Microcell-femtolet based Future Generation Edge-Cloud Network","authors":"Anwesha Mukherjee","doi":"10.23919/URSIGASS51995.2021.9560190","DOIUrl":"https://doi.org/10.23919/URSIGASS51995.2021.9560190","url":null,"abstract":"Fast and low power offloading is an emerging area of interest for future generation mobile network. This paper proposes a partial computation offloading strategy for microcell-femtolet based edge-cloud network. In the microcell-femtolet network microcells contain femtolets inside their coverage area to provide good communication and computation facilities to the user devices at indoor region. An indoor user is connected with the femtolet and an outdoor user is connected with the microcell base station in the microcell-femtolet network scenario. When a computation has to be partially offloaded, the task is partitioned into two segments, one is locally executed and the other one is offloaded to the femtolet or edge server according to the user's presence at indoor or outdoor region. The theoretical and experimental results illustrate that the proposed partial offloading scheme reduces the latency and power consumption of the mobile device than the cloud based approach.","PeriodicalId":152047,"journal":{"name":"2021 XXXIVth General Assembly and Scientific Symposium of the International Union of Radio Science (URSI GASS)","volume":"49 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":"131277222","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
ConvNet Fine-Tuning Investigation for GPR Images Classification GPR图像分类的ConvNet微调研究
2021 XXXIVth General Assembly and Scientific Symposium of the International Union of Radio Science (URSI GASS) Pub Date : 2021-08-28 DOI: 10.23919/URSIGASS51995.2021.9560298
Mostafa Elsaadouny, J. Barowski, I. Rolfes
{"title":"ConvNet Fine-Tuning Investigation for GPR Images Classification","authors":"Mostafa Elsaadouny, J. Barowski, I. Rolfes","doi":"10.23919/URSIGASS51995.2021.9560298","DOIUrl":"https://doi.org/10.23919/URSIGASS51995.2021.9560298","url":null,"abstract":"Deep learning has been widely implemented as a new classification platform during the past few years. One of the main problems facing deep learning is the problem of data dependency as it requires a very large amount of data for training. Therefore, transfer learning (TL) has been introduced as a solution to this problem. This study focuses on the fine-tuning strategy of the transfer learning and how it can be implemented to classify the ground-penetrating radar (GPR) images. The GPR data has been collected and processed using the matched filter algorithm and further clutter reduction techniques. The resultant GPR images compromises of a limited number of samples, therefore, the deployed convolutional neural network (ConvNet) has been trained first using another larger dataset, then fine-tuned using the GPR dataset. The obtained results are promising and show a high degree of precision and accuracy compared to previously conducted researches.","PeriodicalId":152047,"journal":{"name":"2021 XXXIVth General Assembly and Scientific Symposium of the International Union of Radio Science (URSI GASS)","volume":"39 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":"127310880","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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