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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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Waveform-Selective Devices for Antenna Applications 天线应用的波形选择器件
2020 XXXIIIrd General Assembly and Scientific Symposium of the International Union of Radio Science Pub Date : 2020-08-01 DOI: 10.23919/URSIGASS49373.2020.9232253
S. Vellucci, M. Barbuto, A. Monti, A. Toscano, F. Bilotti
{"title":"Waveform-Selective Devices for Antenna Applications","authors":"S. Vellucci, M. Barbuto, A. Monti, A. Toscano, F. Bilotti","doi":"10.23919/URSIGASS49373.2020.9232253","DOIUrl":"https://doi.org/10.23919/URSIGASS49373.2020.9232253","url":null,"abstract":"In this contribution, we investigate several examples of antenna applications of waveform-selective devices, i.e., structures exhibiting different responses depending on the waveform of the incoming waves. In particular, as a first example, we describe an open-ended waveguide capped with an iris band-pass filter loaded with a lumped-element circuit. Thanks to the frequency- and time-domain selectivity properties of the loaded iris, the aperture antenna exhibits different radiating patterns depending on the waveform of the transmitted/received signal. Then, the same lumped-element circuit is used to design an antenna that is made invisible/visible to either a short pulse or a continuous signal. Exploiting a peculiar meandered cloaking metasurface loaded by the lumped-element circuit, the cloaking effects is automatically turned on/off depending on the time-domain characteristics of the incoming signal. This study aims paving the way for the design of antenna systems equipped with both frequency- and time-domain selectivity properties.","PeriodicalId":438881,"journal":{"name":"2020 XXXIIIrd General Assembly and Scientific Symposium of the International Union of Radio Science","volume":"15 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":"134090320","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
Real-Time Tropospheric Delay Estimation Using GPS/Galileo Observations and NAVCAST Products 基于GPS/Galileo观测和NAVCAST产品的对流层实时延迟估计
2020 XXXIIIrd General Assembly and Scientific Symposium of the International Union of Radio Science Pub Date : 2020-08-01 DOI: 10.23919/URSIGASS49373.2020.9232439
M. Abdelazeem, A. El-Rabbany
{"title":"Real-Time Tropospheric Delay Estimation Using GPS/Galileo Observations and NAVCAST Products","authors":"M. Abdelazeem, A. El-Rabbany","doi":"10.23919/URSIGASS49373.2020.9232439","DOIUrl":"https://doi.org/10.23919/URSIGASS49373.2020.9232439","url":null,"abstract":"Precise estimation of real-time zenith tropospheric delay (RT-ZTD) is critical for real-time atmospheric sounding applications. Recently, the NAVCAST real-time service has been launched, which provides GPS/Galileo precise satellite orbit and clock corrections. This study aims to assess the precision of real-time zenith tropospheric delay obtained through the real-time GPS/Galileo precise point positioning (RT-PPP) solution. GPS/Galileo observations, spanning three successive days, from a number of globally distributed reference stations are first acquired and processed in the real-time mode using the NAVCAST real-time products. The RT-ZTD is then estimated and compared with the center for orbit determination in Europe (CODE) rapid tropospheric product counterpart. It is shown that the RT-ZTD estimates are in good agreement with the CODE counterparts with a maximum standard deviation (STD) of 22.2 mm. The addition of Galileo observations improves the precision of the RT-ZTD estimates by about 25% in comparison with the GPS-only solution.","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":"114227760","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
Numerical Investigation of a self-detuning Signal Enhancement Metasurface for 3T MRI 3T MRI自失谐信号增强超表面的数值研究
2020 XXXIIIrd General Assembly and Scientific Symposium of the International Union of Radio Science Pub Date : 2020-08-01 DOI: 10.23919/URSIGASS49373.2020.9232401
Endri Stoja, Dennis Philipp, Diego Betancourt, S. Konstandin, R. Wilke, Reinhold Umathum, J. Jenne, T. Bertuch, M. Günther
{"title":"Numerical Investigation of a self-detuning Signal Enhancement Metasurface for 3T MRI","authors":"Endri Stoja, Dennis Philipp, Diego Betancourt, S. Konstandin, R. Wilke, Reinhold Umathum, J. Jenne, T. Bertuch, M. Günther","doi":"10.23919/URSIGASS49373.2020.9232401","DOIUrl":"https://doi.org/10.23919/URSIGASS49373.2020.9232401","url":null,"abstract":"In this work, numerical simulation results regarding an automatically self-detuning signal enhancement plate (DSEP) for use in magnetic resonance imaging at 3T field are presented. The DSEP is composed of a linear alignment of wire resonators milled on a suitable PCB and inductively coupled to a varactor-loaded detuning loop. Eigenmode simulations allow to design the coupled system, whereas full-wave simulations of the device, excited by a circularly-polarized plane wave in the pres-ence of a phantom, show the detuning efficiency. In terms of H-field magnitude, a maximal enhancement factor of about four is observed at the target frequency of 123.5 MHz.","PeriodicalId":438881,"journal":{"name":"2020 XXXIIIrd General Assembly and Scientific Symposium of the International Union of Radio Science","volume":"201 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":"114230325","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
Rotational Artefact Removal for Radar-based Breast Imaging: Effects on Image Quality 基于雷达的乳房成像旋转伪影去除:对图像质量的影响
2020 XXXIIIrd General Assembly and Scientific Symposium of the International Union of Radio Science Pub Date : 2020-08-01 DOI: 10.23919/URSIGASS49373.2020.9232244
Declan O’Loughlin, H. Benchakroun, A. Lowery
{"title":"Rotational Artefact Removal for Radar-based Breast Imaging: Effects on Image Quality","authors":"Declan O’Loughlin, H. Benchakroun, A. Lowery","doi":"10.23919/URSIGASS49373.2020.9232244","DOIUrl":"https://doi.org/10.23919/URSIGASS49373.2020.9232244","url":null,"abstract":"Radar-based breast imaging has shown promise as an imaging modality for early-stage cancer detection, and clinical investigations of two commercial imaging systems are on-going. Many imaging algorithms have been proposed, which seek to improve the quality of the reconstructed microwave image to enhance the potential clinical decision. However, a large artefact caused by the interface between the skin and breast interior can obscure reflections from the breast interior and, hence, tumour detection. Rotational subtraction is commonly employed to remove this artefact, however, limited work has examined the optimal parameters for rotational subtraction. In this work, the theoretical basis for rotational subtraction is examined, and the potential negative effects on image quality identified. Overall, this work suggests that it is important that the parameters of rotational artefact removal be optimised to improve radar-based breast image quality.","PeriodicalId":438881,"journal":{"name":"2020 XXXIIIrd General Assembly and Scientific Symposium of the International Union of Radio Science","volume":"137 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":"116725069","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
Digital Images Preprocessing for Optical Character Recognition in Video Frames Reconstructed from Compromising Electromagnetic Emanations from Video Cables 视频电缆电磁辐射重构视频帧中光学字符识别的数字图像预处理
2020 XXXIIIrd General Assembly and Scientific Symposium of the International Union of Radio Science Pub Date : 2020-08-01 DOI: 10.23919/URSIGASS49373.2020.9232388
Santiago Morales-Aguilar, C. Kasmi, M. Meriac, F. Vega, Fahad Alyafei
{"title":"Digital Images Preprocessing for Optical Character Recognition in Video Frames Reconstructed from Compromising Electromagnetic Emanations from Video Cables","authors":"Santiago Morales-Aguilar, C. Kasmi, M. Meriac, F. Vega, Fahad Alyafei","doi":"10.23919/URSIGASS49373.2020.9232388","DOIUrl":"https://doi.org/10.23919/URSIGASS49373.2020.9232388","url":null,"abstract":"This work presents an analysis of the performance of two different preprocessing techniques for improving the quality of video frames previously reconstructed from compromising electromagnetic emanations produced by video interfaces connecting external monitors. Each technique depends on parameters such as white and black thresholds, kernel size of blur filter, contrast gain, brightness level, among others, and for this reason, an optimization process is applied by implementing an evolution $strategy$.","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":"117162265","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
Investigation of Accelerated Monostatic Radar Cross Section Computations by Using Block and Projection Iterative Methods 基于块迭代法和投影迭代法的单基地雷达截面加速计算研究
2020 XXXIIIrd General Assembly and Scientific Symposium of the International Union of Radio Science Pub Date : 2020-08-01 DOI: 10.23919/URSIGASS49373.2020.9232429
D. Ostrzyharczik, T. Eibert
{"title":"Investigation of Accelerated Monostatic Radar Cross Section Computations by Using Block and Projection Iterative Methods","authors":"D. Ostrzyharczik, T. Eibert","doi":"10.23919/URSIGASS49373.2020.9232429","DOIUrl":"https://doi.org/10.23919/URSIGASS49373.2020.9232429","url":null,"abstract":"Accurate numerical solutions of scattering phenomena can be achieved by method of moments (MoM) solutions of integral equations. For the evaluation of the monostatic radar cross section (RCS) of an object, the same system of equations has to be solved many times for different excitation fields incident from many directions. Especially for electrically large bodies involving many millions of unknowns, this becomes computationally demanding. In this work, we study and compare the performance of block and projection iterative methods for MoM solutions of surface integral equations related to perfect electrically conducting objects. Both methods are capable of reducing the overall number of matrix-vector products in the considered iterative solution process.","PeriodicalId":438881,"journal":{"name":"2020 XXXIIIrd General Assembly and Scientific Symposium of the International Union of Radio Science","volume":"106 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":"116233517","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
Multi-Frequency Inversion of Scattered-Field Data in Lebesgue Spaces with Nonconstant Exponents 非常指数Lebesgue空间中散射场数据的多频反演
2020 XXXIIIrd General Assembly and Scientific Symposium of the International Union of Radio Science Pub Date : 2020-08-01 DOI: 10.23919/URSIGASS49373.2020.9232449
A. Fedeli, C. Estatico, A. Randazzo, M. Pastorino
{"title":"Multi-Frequency Inversion of Scattered-Field Data in Lebesgue Spaces with Nonconstant Exponents","authors":"A. Fedeli, C. Estatico, A. Randazzo, M. Pastorino","doi":"10.23919/URSIGASS49373.2020.9232449","DOIUrl":"https://doi.org/10.23919/URSIGASS49373.2020.9232449","url":null,"abstract":"The quantitative retrieval of the dielectric properties of structures from scattered-field measurements at microwave frequencies is relevant for a wide range of applications. To accomplish this task, a key point is represented by the effective exploitation of the available information, including frequency diversity. In this contribution, a quantitative imaging method that works in Lebesgue spaces with nonconstant exponents is extended in order to perform a multi-frequency inversion. The proposed technique is validated against experimental data.","PeriodicalId":438881,"journal":{"name":"2020 XXXIIIrd General Assembly and Scientific Symposium of the International Union of Radio Science","volume":"33 5 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":"115013644","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 Wideband Low-Profile Antenna for LTE/5G LTE/5G宽带低轮廓天线
2020 XXXIIIrd General Assembly and Scientific Symposium of the International Union of Radio Science Pub Date : 2020-08-01 DOI: 10.23919/URSIGASS49373.2020.9232183
R. Singh, A. Michel, P. Nepa, G. Manara
{"title":"A Wideband Low-Profile Antenna for LTE/5G","authors":"R. Singh, A. Michel, P. Nepa, G. Manara","doi":"10.23919/URSIGASS49373.2020.9232183","DOIUrl":"https://doi.org/10.23919/URSIGASS49373.2020.9232183","url":null,"abstract":"A wideband low-profile antenna for Long Term Evolution (LTE) and 5G technology is presented in this paper. It is designed to be mounted on a car roof underneath the shark-fin cover. Proposed antenna operates at a wide frequency range from 617 MHz to 5.5 GHz. Wide frequency band is obtained without using any matching network in the design. Antenna has an omnidirectional radiation pattern throughout the band. Antenna prototype is fabricated and preliminary measured results in terms of input impedance matching are shown.","PeriodicalId":438881,"journal":{"name":"2020 XXXIIIrd General Assembly and Scientific Symposium of the International Union of Radio Science","volume":"76 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":"115459044","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
Air-filled Substrate-Integrated Waveguide Technology for Broadband and Highly-Efficient Photonic-Enabled Antenna Systems 用于宽带和高效光子天线系统的充气基板集成波导技术
2020 XXXIIIrd General Assembly and Scientific Symposium of the International Union of Radio Science Pub Date : 2020-08-01 DOI: 10.23919/URSIGASS49373.2020.9232291
S. Lemey, O. Caytan, Quinten Van den Brande, Igor Lima de Paula, L. Bogaert, Haolin Li, J. V. Kerrebrouck, A. Reniers, B. Smolders, J. Bauwelinck, P. Demeester, G. Torfs, D. Ginste, S. Verstuyft, B. Kuyken, H. Rogier
{"title":"Air-filled Substrate-Integrated Waveguide Technology for Broadband and Highly-Efficient Photonic-Enabled Antenna Systems","authors":"S. Lemey, O. Caytan, Quinten Van den Brande, Igor Lima de Paula, L. Bogaert, Haolin Li, J. V. Kerrebrouck, A. Reniers, B. Smolders, J. Bauwelinck, P. Demeester, G. Torfs, D. Ginste, S. Verstuyft, B. Kuyken, H. Rogier","doi":"10.23919/URSIGASS49373.2020.9232291","DOIUrl":"https://doi.org/10.23919/URSIGASS49373.2020.9232291","url":null,"abstract":"The combination of microwave photonics, radio-over-fiber (RoF) and air-filled substrate-integrated-waveguide (AFSIW) technology opens many promising pathways to realize robust, broadband, and highly-integrated multi-antenna systems that address the stringent demands of (beyond-)5G wireless applications. In this paper, we demonstrate the potential of such a multi-disciplinary approach by discussing three designs. First, two AFSIW-based photonic-enabled remote antenna units (RAUs) are presented for downlink sub-6GHz RoF. By adopting an extensive full-wave/circuit co-simulation model, the power transfer between the optical and electrical domain is maximized. In the first design, this is done by using a Chebyshev impedance matching network, while the second design exploits conjugate matching. Second, a hybrid integration strategy for compact, broadband and highly efficient mmWave antennas is introduced. Its excellent performance is proven by realizing an on-chip AFSIW stacked patch antenna. In addition, the design facilitates compact integration of the opto-electronic front-end, making it attractive for the realization of next-generation photonic-enabled mmWave planar multi-antenna systems.","PeriodicalId":438881,"journal":{"name":"2020 XXXIIIrd General Assembly and Scientific Symposium of the International Union of Radio Science","volume":"44 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":"124874291","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 Implementation of Neural Networks for Phaseless Parametric Inversion 无相参数反演的神经网络实现
2020 XXXIIIrd General Assembly and Scientific Symposium of the International Union of Radio Science Pub Date : 2020-08-01 DOI: 10.23919/URSIGASS49373.2020.9232216
Keeley Edwards, Kennedy Krakalovich, R. Kruk, Vahab Khoshdel, J. Lovetri, C. Gilmore, I. Jeffrey
{"title":"The Implementation of Neural Networks for Phaseless Parametric Inversion","authors":"Keeley Edwards, Kennedy Krakalovich, R. Kruk, Vahab Khoshdel, J. Lovetri, C. Gilmore, I. Jeffrey","doi":"10.23919/URSIGASS49373.2020.9232216","DOIUrl":"https://doi.org/10.23919/URSIGASS49373.2020.9232216","url":null,"abstract":"We present a machine learning work flow for the parametric inversion of grain bin measurements in which a neural network is trained solely on synthetic data for a unique bin geometry. This neural network can subsequently be used to rapidly obtain 4 inversion parameters (grain height, cone angle, and bulk real and imaginary permittivity of the grain) from uncalibrated, experimental data. We have previously shown that these 4 parameters can be used to calibrate experimental data and serve as prior information for full-data inversion. Our results show that a densely connected neural network that supports multifrequency data can better predict the cone angle of grain, and perform almost as well on grain height predictions, as the single-frequency simplex inversion method previously described. These findings suggest that neural networks trained on synthetic data may be a useful tool in the inversion of experimental data, providing prior information and a method for calibration.","PeriodicalId":438881,"journal":{"name":"2020 XXXIIIrd General Assembly and Scientific Symposium of the International Union of Radio Science","volume":"40 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":"124933957","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
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