- 标题
- 摘要
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- 实验方案
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[IEEE 2019 International Topical Meeting on Microwave Photonics (MWP) - Ottawa, ON, Canada (2019.10.7-2019.10.10)] 2019 International Topical Meeting on Microwave Photonics (MWP) - Brillouin-Based Signal Processing in Silicon Photonics : (Invited paper)
摘要： We present in this work a first performance assessment of the Parallel Small BAseline Subset (P-SBAS) algorithm, for the generation of Differential Synthetic Aperture Radar (SAR) Interferometry (DInSAR) deformation maps and time series, which has been migrated to a Cloud Computing (CC) environment. In particular, we investigate the scalable performances of the P-SBAS algorithm by processing a selected ENVISAT ASAR image time series, which we use as a benchmark, and by exploiting the Amazon Web Services (AWS) CC platform. The presented analysis shows a very good match between the theoretical and experimental P-SBAS performances achieved within the CC environment. Moreover, the obtained results demonstrate that the implemented P-SBAS Cloud migration is able to process ENVISAT SAR image time series in short times (less than 7 h) and at low costs (about USD 200). The P-SBAS Cloud scalable performances are also compared to those achieved by exploiting an in-house High Performance Computing (HPC) cluster, showing that nearly no overhead is introduced by the presented Cloud solution. As a further outcome, the performed analysis allows us to identify the major bottlenecks that can hamper the P-SBAS performances within a CC environment, in the perspective of processing very huge SAR data flows such as those coming from the existing COSMO-SkyMed or the upcoming SENTINEL-1 constellation. This work represents a relevant step toward the challenging Earth Observation scenario focused on the joint exploitation of advanced DInSAR techniques and CC environments for the massive processing of Big SAR Data.
关键词： Big data,Differential Synthetic Aperture Radar (SAR) Interferometry (DInSAR),Cloud Computing (CC),Parallel Small BAseline Subset (P-SBAS),Earth surface deformation
更新于2025-09-19 17:13:59
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[IEEE 2019 PhotonIcs & Electromagnetics Research Symposium - Spring (PIERS-Spring) - Rome, Italy (2019.6.17-2019.6.20)] 2019 PhotonIcs & Electromagnetics Research Symposium - Spring (PIERS-Spring) - A Singular Value Decomposition Based Approach for Classifying Concealed Objects in Short Range Polarimetric Radar Imaging
摘要： In current research one of the main challenges in short range synthetic aperture radar (SAR) is electrically small structures and objects, which tend to unclear reinforced or through the wall objects, object orientation angle, and obscure contribution to extract the position of concealed multiple small objects. In this paper, ultra-wide-band (UWB) polarimetric radar was used to study reinforced objects and for estimation of object angle at short range. Electrically small 1D periodic mesh, 2D periodic meshes and di?erently oriented small objects or meshes could not be distinguished in conventional SAR images. A radar system with transmit and receive antennae mounted on a two dimensional scanning grid was used. The aim is non-destructive testing of built structures, in concrete slab manufacturing and for use in the renovation process. UWB short range radar data and images corresponding to di?erent polarization states were analysed by using singular value decomposition (SVD). To perform decomposition, the proposed approach applies SVD to image data matrices produced from the back projection algorithm (BPA) to classify the di?erent objects and identify the object angle. Then, sets of singular-components of di?erent polarization states are analysed to classify objects. Also, the BPA algorithm is performed to construct the object images from the polarimetric radar signals. The object re?ection varied with the polarimetric state of the UWB radar, which contributes to di?erent object signatures (i.e., object intensity) since the object signature depends on the orientation, the size, and the number of objects. Object orientation with respect to the radar system and object anisotropy could be determined from the ratio of the di?erent polarimetric singular-components. This proposed complex data analysis method demonstrates the usefulness of the SVD using BPA in extracting more information about and for classifying an object.
关键词： back projection algorithm (BPA),object classification,ultra-wide-band (UWB) polarimetric radar,Synthetic aperture radar (SAR),singular value decomposition (SVD)
更新于2025-09-19 17:13:59
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[IEEE 2019 IEEE 46th Photovoltaic Specialists Conference (PVSC) - Chicago, IL, USA (2019.6.16-2019.6.21)] 2019 IEEE 46th Photovoltaic Specialists Conference (PVSC) - Enabling Behind-the-Meter Distributed Energy Resources to Provide Grid Services
摘要： We discuss the effects of the clutter on geosynchronous SAR systems exploiting long integration times (from minutes to hours) to counteract for two-way propagation losses and increase azimuth resolution. Only stable targets will be correctly focused whereas unstable targets will spread their energy along azimuth direction. We derive here a generic model for the spreading of the clutter energy based on the power spectral density of the clutter itself. We then assume the Billingsley Intrinsic Clutter Motion model, representing the clutter power spectrum as an exponential decay, and derive the expected GEOSAR signal-to-clutter ratio. We also provide some results from a Ground Based RADAR experiment aimed at assessing the long-term clutter statistics for different scenarios to complement the Internal Clutter Motion model, mainly derived for windblown trees. Finally, we discuss the expected performances of two GEOSAR systems with different acquisition geometries.
关键词： scene decorrelation,Focusing,wind-blown clutter,Geosynchronous Synthetic Aperture Radar (GEOSAR)
更新于2025-09-19 17:13:59
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[IEEE 2019 International Conference on Electromechanical and Energy Systems (SIELMEN) - Craiova, Romania (2019.10.9-2019.10.11)] 2019 International Conference on Electromechanical and Energy Systems (SIELMEN) - Photovoltaic Technical Potential in Republic of Moldova
摘要： This paper introduces a framework for robust parameter estimation in multipass interferometric synthetic aperture radar (InSAR), such as persistent scatterer interferometry, SAR tomography, small baseline subset, and SqueeSAR. These techniques involve estimation of phase history parameters with or without covariance matrix estimation. Typically, their optimal estimators are derived on the assumption of stationary complex Gaussian-distributed observations. However, their statistical robustness has not been addressed with respect to observations with nonergodic and non-Gaussian multivariate distributions. The proposed robust InSAR optimization (RIO) framework answers two fundamental questions in multipass InSAR: 1) how to optimally treat images with a large phase error, e.g., due to unmolded motion phase, uncompensated atmospheric phase, etc.; and 2) how to estimate the covariance matrix of a non-Gaussian complex InSAR multivariate, particularly those with nonstationary phase signals. For the former question, RIO employs a robust M-estimator to effectively downweight these images; and for the latter, we propose a new method, i.e., the rank M -estimator, which is robust against non-Gaussian distribution. Furthermore, it can work without the assumption of sample stationarity, which is a topic that has not previously been addressed. We demonstrate the advantages of the proposed framework for data with large phase error and heavily tailed distribution, by comparing it with state-of-the-art estimators for persistent and distributed scatterers. Substantial improvement can be achieved in terms of the variance of estimates. The proposed framework can be easily extended to other multipass InSAR techniques, particularly to those where covariance matrix estimation is vital.
关键词： robust estimation,M -estimator,SAR interferometry (InSAR),robust InSAR optimization (RIO),rank covariance matrix,Differential interferometric synthetic aperture radar (D-InSAR)
更新于2025-09-19 17:13:59
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[IEEE 2019 IEEE 8th International Conference on Advanced Optoelectronics and Lasers (CAOL) - Sozopol, Bulgaria (2019.9.6-2019.9.8)] 2019 IEEE 8th International Conference on Advanced Optoelectronics and Lasers (CAOL) - Model of wide-aperture laser with intracavity diffractive element
摘要： We propose new simulation model of wide-aperture laser with diffractive elements. This model based on edge dislocation wave that derived from rigorous Sommerfeld solution of plane wave diffraction on half-plane. The model is of non-paraxial nature that allows to simulate the transversal laser mode evolution with intracavity diffractive elements. We discuss the limitations of proposed model. The comparison with well-known methods of wave propagation based on Fourier transform and Kirchhoff integral is also given. The computational complexity is estimated. The possible applications are given.
关键词： intracavity diffractive elements,laser beam propagations,wide-aperture laser
更新于2025-09-19 17:13:59
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[IEEE 2019 IEEE 8th Global Conference on Consumer Electronics (GCCE) - Osaka, Japan (2019.10.15-2019.10.18)] 2019 IEEE 8th Global Conference on Consumer Electronics (GCCE) - A Universal VLC Modulator for Retrofitting LED Lighting and Signage
摘要： The Advanced Radar Geosynchronous Observation System is proposed to be a multiple-input–multiple-output synthetic aperture radar (SAR) system hosted on a swarm of minisatellites in quasi-geostationary orbits. The system is made of N iso-frequency sensors, each of them transmitting and receiving the signals. The system would combine the continuous imaging capabilities of a geostationary SAR, gaining a factor N 2 in signal-to-noise ratio (SNR). The real aperture would be achievable in ～40 min, enabling applications so far unseen, such as monitoring fast deformations, landslides, and other applications for emergency and security. Still, the SNR of the long acquisition time would be conserved. The optimal design of the swarm is addressed, in order to trade resolution, coverage, and revisit time.
关键词： synthetic aperture radar (SAR),spaceborne radar,Earth Observing System,radar interferometry,multiple-input–multiple-output (MIMO) radar
更新于2025-09-19 17:13:59
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[IEEE GLOBECOM 2019 - 2019 IEEE Global Communications Conference - Waikoloa, HI, USA (2019.12.9-2019.12.13)] 2019 IEEE Global Communications Conference (GLOBECOM) - Mutual Information and Noise Distributions of Molecular Signals Using Laser Induced Fluorescence
摘要： In this communication, a recon?gurable feeding network is proposed for the design of a quad-polarization-agile antenna. By switching the PIN diodes, the four transmission modes with selected phase differences can be electrically tuned at two output ports. For each mode, the measured insertion loss of the feeding network is less than 0.8 dB at the operating frequency. Because of its compact size, the proposed feeding network can be further integrated with a dual-polarized aperture-coupled antenna, which can exhibit two orthogonal linear polarizations and two orthogonal circular polarizations. Measured results of the polarization-agile antenna are shown in detail, which verify its performance.
关键词： recon?gurable antenna,circular and linear polarization,recon?gurable feeding network,Aperture-coupled patch antenna,polarization-agile
更新于2025-09-19 17:13:59
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Analysis of Seasonal Aspects of Nebulosity on the Project of Fixed Photovoltaic Installations at the City of Bel??m, Brazil
摘要： In this paper, we adopt the coded aperture technique to the alignment process for industrial machinery. As a special setting for assembly and inspection, such machinery uses an illumination of narrow wavelength range for imaging with less aberration. This leads to significant influence of light diffraction on the image restoration. Although the diffraction was treated as negligible in most previous studies of coded aperture since they were carried out for natural images, the aperture patterns of them do not achieve enough accuracy for the alignment. We optimize the aperture pattern by performing a simulation of light diffraction, and we experimentally show that it achieves better performance in the alignment.
关键词： Alignment,industrial machinery,template matching,light diffraction,coded aperture,inspection,image restoration,factory automation
更新于2025-09-19 17:13:59
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Tunable and Switchable Multi-wavelength Erbium-Brillouin Random Fiber Laser Incorporating a Highly Nonlinear Fiber
摘要： In this communication, a recon?gurable feeding network is proposed for the design of a quad-polarization-agile antenna. By switching the PIN diodes, the four transmission modes with selected phase differences can be electrically tuned at two output ports. For each mode, the measured insertion loss of the feeding network is less than 0.8 dB at the operating frequency. Because of its compact size, the proposed feeding network can be further integrated with a dual-polarized aperture-coupled antenna, which can exhibit two orthogonal linear polarizations and two orthogonal circular polarizations. Measured results of the polarization-agile antenna are shown in detail, which verify its performance.
关键词： recon?gurable antenna,circular and linear polarization,recon?gurable feeding network,Aperture-coupled patch antenna,polarization-agile
更新于2025-09-19 17:13:59
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[IEEE 2019 Workshop on Recent Advances in Photonics (WRAP) - Guwahati, India (2019.12.13-2019.12.14)] 2019 Workshop on Recent Advances in Photonics (WRAP) - High-Speed Cavity Enhanced Silicon Photodetector on SiN-SOI Platform for Short Reach Optical Datacom
摘要： In this communication, a recon?gurable feeding network is proposed for the design of a quad-polarization-agile antenna. By switching the PIN diodes, the four transmission modes with selected phase differences can be electrically tuned at two output ports. For each mode, the measured insertion loss of the feeding network is less than 0.8 dB at the operating frequency. Because of its compact size, the proposed feeding network can be further integrated with a dual-polarized aperture-coupled antenna, which can exhibit two orthogonal linear polarizations and two orthogonal circular polarizations. Measured results of the polarization-agile antenna are shown in detail, which verify its performance.
关键词： recon?gurable antenna,circular and linear polarization,recon?gurable feeding network,Aperture-coupled patch antenna,polarization-agile
更新于2025-09-19 17:13:59