Pub Date : 2019-01-01DOI: 10.23919/USNC-URSI-NRSM.2019.8713048
P. Bernhardt, M. Griffin, William C. Bougas, A. Howarth, H. G. James
Data were collected with Canadian e-POP instruments to measure electric fields (10 Hz to 30 kHz) with the Radio Receiver Instrument (RRI) and the 3-axis magnetometer (MGF) in the 62.5 pt to 65.536 μt range. The electric field measurements showed waves ULF (210 Hz) and VLF (14 kHz) range that varied along the orbit and were disturbed by the firing of the Cygnus satellite rocket motor 50 km away. A number of questions are raised by the observations including: Are the observations attributable to Cygnus? Are the observed harmonics instrumental or physical? What are the plasma wave generation and propagation modes? The observations are used to infer natural and artificial changes in the ionosphere.
{"title":"Composition of the Topside Ionosphere Determined from Plasma Wave Measurements Using the Radio Receiver Instrument on e-POP","authors":"P. Bernhardt, M. Griffin, William C. Bougas, A. Howarth, H. G. James","doi":"10.23919/USNC-URSI-NRSM.2019.8713048","DOIUrl":"https://doi.org/10.23919/USNC-URSI-NRSM.2019.8713048","url":null,"abstract":"Data were collected with Canadian e-POP instruments to measure electric fields (10 Hz to 30 kHz) with the Radio Receiver Instrument (RRI) and the 3-axis magnetometer (MGF) in the 62.5 pt to 65.536 μt range. The electric field measurements showed waves ULF (210 Hz) and VLF (14 kHz) range that varied along the orbit and were disturbed by the firing of the Cygnus satellite rocket motor 50 km away. A number of questions are raised by the observations including: Are the observations attributable to Cygnus? Are the observed harmonics instrumental or physical? What are the plasma wave generation and propagation modes? The observations are used to infer natural and artificial changes in the ionosphere.","PeriodicalId":142320,"journal":{"name":"2019 United States National Committee of URSI National Radio Science Meeting (USNC-URSI NRSM)","volume":"65 5 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115653829","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}
Pub Date : 2019-01-01DOI: 10.23919/USNC-URSI-NRSM.2019.8712863
Vigyanshu Mishra, A. Kiourti
This work introduces a novel approach for monitoring joint flexion. Specifically, Radio-Frequency coils (in transmitting and receiving modes) placed symmetrically about the joint are proposed to monitor flexion by leveraging changes in the transmission coefficient as the limb flexes and extends. To demonstrate the idea, simulations in a cylindrical and homogeneous limb model are performed. Results clearly show the feasibility of monitoring joint flexion/extension using the proposed approach. This provides a new way of monitoring joint flexion while overcoming shortcomings in the state-of-the-art. Numerous medical and consumer applications may eventually benefit from the proposed approach.
{"title":"Breaking the Boundaries: Monitoring Joint Flexion Using Radio-Frequency Coils","authors":"Vigyanshu Mishra, A. Kiourti","doi":"10.23919/USNC-URSI-NRSM.2019.8712863","DOIUrl":"https://doi.org/10.23919/USNC-URSI-NRSM.2019.8712863","url":null,"abstract":"This work introduces a novel approach for monitoring joint flexion. Specifically, Radio-Frequency coils (in transmitting and receiving modes) placed symmetrically about the joint are proposed to monitor flexion by leveraging changes in the transmission coefficient as the limb flexes and extends. To demonstrate the idea, simulations in a cylindrical and homogeneous limb model are performed. Results clearly show the feasibility of monitoring joint flexion/extension using the proposed approach. This provides a new way of monitoring joint flexion while overcoming shortcomings in the state-of-the-art. Numerous medical and consumer applications may eventually benefit from the proposed approach.","PeriodicalId":142320,"journal":{"name":"2019 United States National Committee of URSI National Radio Science Meeting (USNC-URSI NRSM)","volume":"2 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"117221188","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}
Pub Date : 2019-01-01DOI: 10.23919/USNC-URSI-NRSM.2019.8713084
S. Chowdhury, R. Rasel, F. Teixeira, Q. Marashdeh
In this paper, a soft-field tomography-based velocity profile reconstruction is conducted for different two-phase flow models. The method is based on the use of the sensor sensitivity gradient in the region of interest based on a Laplacian interrogating field. The described method offers a robust and reliable velocity profile measurement over earlier cross-correlation-based methods.
{"title":"Velocity Profiling of Two-phase Flows Based on Soft-Field Volume Tomography","authors":"S. Chowdhury, R. Rasel, F. Teixeira, Q. Marashdeh","doi":"10.23919/USNC-URSI-NRSM.2019.8713084","DOIUrl":"https://doi.org/10.23919/USNC-URSI-NRSM.2019.8713084","url":null,"abstract":"In this paper, a soft-field tomography-based velocity profile reconstruction is conducted for different two-phase flow models. The method is based on the use of the sensor sensitivity gradient in the region of interest based on a Laplacian interrogating field. The described method offers a robust and reliable velocity profile measurement over earlier cross-correlation-based methods.","PeriodicalId":142320,"journal":{"name":"2019 United States National Committee of URSI National Radio Science Meeting (USNC-URSI NRSM)","volume":"112 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124029804","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}
Pub Date : 2019-01-01DOI: 10.23919/USNC-URSI-NRSM.2019.8713155
R. Rasel, Daniel Ospina Acero, F. Teixeira, Q. Marashdeh
Process tomography is a well established imaging modality to monitor a variety of flow processes in industrial applications. Traditionally, this has been done through imaging of a cross section of the domain. In recent years, much interest has been devoted to volume process tomography, where a three-dimensional reconstruction is directly obtained. However, depending on the sensor design, the number of independent measurements can be much higher in volume tomography compared to its two-dimensional counterpart. This makes the reconstruction problem more challenging and may prevent real-time monitoring in certain cases. In this work we investigate the optimal choice of cross-layer measurements to provide accurate volumetric tomography while minimizing image reconstruction costs using electrical capacitance volume tomography as example.
{"title":"Evaluating Cross-Plane Acquisitions for Volume Process Tomography in the Laplacian Regime","authors":"R. Rasel, Daniel Ospina Acero, F. Teixeira, Q. Marashdeh","doi":"10.23919/USNC-URSI-NRSM.2019.8713155","DOIUrl":"https://doi.org/10.23919/USNC-URSI-NRSM.2019.8713155","url":null,"abstract":"Process tomography is a well established imaging modality to monitor a variety of flow processes in industrial applications. Traditionally, this has been done through imaging of a cross section of the domain. In recent years, much interest has been devoted to volume process tomography, where a three-dimensional reconstruction is directly obtained. However, depending on the sensor design, the number of independent measurements can be much higher in volume tomography compared to its two-dimensional counterpart. This makes the reconstruction problem more challenging and may prevent real-time monitoring in certain cases. In this work we investigate the optimal choice of cross-layer measurements to provide accurate volumetric tomography while minimizing image reconstruction costs using electrical capacitance volume tomography as example.","PeriodicalId":142320,"journal":{"name":"2019 United States National Committee of URSI National Radio Science Meeting (USNC-URSI NRSM)","volume":"31 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124121839","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}
Pub Date : 2019-01-01DOI: 10.23919/USNC-URSI-NRSM.2019.8713045
Michael C. Brown, Changzhi Li
In this paper, a K-band monopulse comparator and dual six-port junctions are combined to create a portable planar monopulse receiver. The architecture utilizes the phase offset of the difference signals to reduce the number of necessary downconverters. The full design was implemented with passive microstrip structures, silicon Schottky diodes, and a medium power amplifier. The performance of the design was measured at 24 GHz using a three-element series fed antenna supplied by a voltage-controlled oscillator.
{"title":"A Single Layer Planar K-Band Monopulse Radar Receiver","authors":"Michael C. Brown, Changzhi Li","doi":"10.23919/USNC-URSI-NRSM.2019.8713045","DOIUrl":"https://doi.org/10.23919/USNC-URSI-NRSM.2019.8713045","url":null,"abstract":"In this paper, a K-band monopulse comparator and dual six-port junctions are combined to create a portable planar monopulse receiver. The architecture utilizes the phase offset of the difference signals to reduce the number of necessary downconverters. The full design was implemented with passive microstrip structures, silicon Schottky diodes, and a medium power amplifier. The performance of the design was measured at 24 GHz using a three-element series fed antenna supplied by a voltage-controlled oscillator.","PeriodicalId":142320,"journal":{"name":"2019 United States National Committee of URSI National Radio Science Meeting (USNC-URSI NRSM)","volume":"230 3","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114256473","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}
Pub Date : 2019-01-01DOI: 10.23919/USNC-URSI-NRSM.2019.8713056
O. Manoochehri, F. Farzami, D. Erricolo, Pai-Yen Chen, Amin Darvazehban, A. Shamim, H. Bağcı
An antipodal Vivaldi antenna (AVA) with tapered corrugated edge from 6 GHz to 18 GHz is designed and fabricated. This antenna can be used in ultra-wide band applications that need stable patterns such as in direction finding systems. The two tapered microstrip antennas are printed on the top and bottom sides of a substrate. The microstrip ground plane is eliminated since one of the tapered microstrip is used as a ground plane. In this technique, an unbalanced to balanced balun is not required. The measured antenna gain is 8 dBi while maintaining VSWR less than 2. There is a good agreement between the simulated and measured results.
{"title":"Design of a corrugated antipodal Vivaldi antenna with stable pattern","authors":"O. Manoochehri, F. Farzami, D. Erricolo, Pai-Yen Chen, Amin Darvazehban, A. Shamim, H. Bağcı","doi":"10.23919/USNC-URSI-NRSM.2019.8713056","DOIUrl":"https://doi.org/10.23919/USNC-URSI-NRSM.2019.8713056","url":null,"abstract":"An antipodal Vivaldi antenna (AVA) with tapered corrugated edge from 6 GHz to 18 GHz is designed and fabricated. This antenna can be used in ultra-wide band applications that need stable patterns such as in direction finding systems. The two tapered microstrip antennas are printed on the top and bottom sides of a substrate. The microstrip ground plane is eliminated since one of the tapered microstrip is used as a ground plane. In this technique, an unbalanced to balanced balun is not required. The measured antenna gain is 8 dBi while maintaining VSWR less than 2. There is a good agreement between the simulated and measured results.","PeriodicalId":142320,"journal":{"name":"2019 United States National Committee of URSI National Radio Science Meeting (USNC-URSI NRSM)","volume":"73 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115961049","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}
Pub Date : 2019-01-01DOI: 10.23919/USNC-URSI-NRSM.2019.8713017
Anastasios Papathanasopoulos, Y. Rahmat-Samii
A major disadvantage of natural dielectric lenses is the excessive physical weight of the dielectric material. Artificial dielectric lenses are proposed to replace the actual dielectric and overcome this disadvantage. In this paper, we introduce a systematic and comprehensive method for the design of metallic delay lenses. Previous approaches suggest analytical formulas based on effective medium theories for the evaluation of the effective electromagnetic properties of artificial dielectrics. The method presented in this paper goes beyond the applicability of the theoretical methods, since it is applicable for periodic structures with larger metallic elements that are desired in practice. To validate this method, a metallic delay lens comprising of copper spheres is used as a proof of concept demonstrator and favorably compared with the solid lenses.
{"title":"A Systematic Approach for the design of Metallic Delay Lenses","authors":"Anastasios Papathanasopoulos, Y. Rahmat-Samii","doi":"10.23919/USNC-URSI-NRSM.2019.8713017","DOIUrl":"https://doi.org/10.23919/USNC-URSI-NRSM.2019.8713017","url":null,"abstract":"A major disadvantage of natural dielectric lenses is the excessive physical weight of the dielectric material. Artificial dielectric lenses are proposed to replace the actual dielectric and overcome this disadvantage. In this paper, we introduce a systematic and comprehensive method for the design of metallic delay lenses. Previous approaches suggest analytical formulas based on effective medium theories for the evaluation of the effective electromagnetic properties of artificial dielectrics. The method presented in this paper goes beyond the applicability of the theoretical methods, since it is applicable for periodic structures with larger metallic elements that are desired in practice. To validate this method, a metallic delay lens comprising of copper spheres is used as a proof of concept demonstrator and favorably compared with the solid lenses.","PeriodicalId":142320,"journal":{"name":"2019 United States National Committee of URSI National Radio Science Meeting (USNC-URSI NRSM)","volume":"194 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116452274","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}
Pub Date : 2019-01-01DOI: 10.23919/USNC-URSI-NRSM.2019.8713131
A. Crews, K. Cahoy, W. Blackwell, R. Leslie, I. Osaretin, M. DiLiberto, A. Milstein, M. Grant
Constellations of nanosatellites allow increased observations, improved revisit time, and expanded spatial coverage. Miniaturized microwave radiometers are particularly well-suited to nanosatellite constellations given the relatively wide receive beamwidth and high impact of their contribution to weather forecasting [1]. The Micro-sized Microwave Atmospheric Satellite (MicroMAS)-2A is a 3U CubeSat that launched on January 11, 2018, and provided the first CubeSat microwave atmospheric sounder data from orbit. MicroMAS-2A has a 1U 10-channel passive microwave radiometer with channels near 90, 118, 183, and 206 GHz for moisture and temperature profiling and precipitation imaging [2]. MicroMAS-2A is a pathfinder for the future mission Time-Resolved Observations of Precipitation structure and storm Intensity with a Constellation of Smallsats (TROPICS), which is projected to launch in 2020. In this work, we provide an initial radiance validation assessment of MicroMAS-2A data.
{"title":"Initial Radiance Validation of On-orbit MicroMAS-2A Data","authors":"A. Crews, K. Cahoy, W. Blackwell, R. Leslie, I. Osaretin, M. DiLiberto, A. Milstein, M. Grant","doi":"10.23919/USNC-URSI-NRSM.2019.8713131","DOIUrl":"https://doi.org/10.23919/USNC-URSI-NRSM.2019.8713131","url":null,"abstract":"Constellations of nanosatellites allow increased observations, improved revisit time, and expanded spatial coverage. Miniaturized microwave radiometers are particularly well-suited to nanosatellite constellations given the relatively wide receive beamwidth and high impact of their contribution to weather forecasting [1]. The Micro-sized Microwave Atmospheric Satellite (MicroMAS)-2A is a 3U CubeSat that launched on January 11, 2018, and provided the first CubeSat microwave atmospheric sounder data from orbit. MicroMAS-2A has a 1U 10-channel passive microwave radiometer with channels near 90, 118, 183, and 206 GHz for moisture and temperature profiling and precipitation imaging [2]. MicroMAS-2A is a pathfinder for the future mission Time-Resolved Observations of Precipitation structure and storm Intensity with a Constellation of Smallsats (TROPICS), which is projected to launch in 2020. In this work, we provide an initial radiance validation assessment of MicroMAS-2A data.","PeriodicalId":142320,"journal":{"name":"2019 United States National Committee of URSI National Radio Science Meeting (USNC-URSI NRSM)","volume":"28 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130618005","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}
Pub Date : 2019-01-01DOI: 10.23919/USNC-URSI-NRSM.2019.8712938
M. Hadi, A. Elsherbeni
The main objective of this presentation is to apply discrete FDTD theory to the stretched-coordinates PML for cylindrical FDTD and derive the overall numerical reflection coefficient off the PML region as a function of all algorithmic parameters and harmonic solutions. For brevity, analysis are limited to normal incidence on the radially arrayed PML region. Obtained predictive equations are used to investigate PML absorption as a function of cylindrical harmonics and proximity to the axis of rotation.
{"title":"Predicting PML Performance at Normal Incidence in Cylindrical FDTD","authors":"M. Hadi, A. Elsherbeni","doi":"10.23919/USNC-URSI-NRSM.2019.8712938","DOIUrl":"https://doi.org/10.23919/USNC-URSI-NRSM.2019.8712938","url":null,"abstract":"The main objective of this presentation is to apply discrete FDTD theory to the stretched-coordinates PML for cylindrical FDTD and derive the overall numerical reflection coefficient off the PML region as a function of all algorithmic parameters and harmonic solutions. For brevity, analysis are limited to normal incidence on the radially arrayed PML region. Obtained predictive equations are used to investigate PML absorption as a function of cylindrical harmonics and proximity to the axis of rotation.","PeriodicalId":142320,"journal":{"name":"2019 United States National Committee of URSI National Radio Science Meeting (USNC-URSI NRSM)","volume":"18 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128546862","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}
Pub Date : 2019-01-01DOI: 10.23919/USNC-URSI-NRSM.2019.8713025
J. L. Nicolini, D. Na, F. Teixeira
The Proper Orthogonal Decomposition technique for model order reduction is applied to electromagnetic particle-in-cell algorithms. The resulting low-dimensional model can be used to achieve solutions with acceptable accuracy and reduced computational costs in problems with charged particle beams.
{"title":"Proper Orthogonal Decomposition for Particle-in-Cell Simulations","authors":"J. L. Nicolini, D. Na, F. Teixeira","doi":"10.23919/USNC-URSI-NRSM.2019.8713025","DOIUrl":"https://doi.org/10.23919/USNC-URSI-NRSM.2019.8713025","url":null,"abstract":"The Proper Orthogonal Decomposition technique for model order reduction is applied to electromagnetic particle-in-cell algorithms. The resulting low-dimensional model can be used to achieve solutions with acceptable accuracy and reduced computational costs in problems with charged particle beams.","PeriodicalId":142320,"journal":{"name":"2019 United States National Committee of URSI National Radio Science Meeting (USNC-URSI NRSM)","volume":"21 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114463987","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}
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