Results 181 to 190 of about 489,746 (209)
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Polarimetric Calibration Using a Genetic Algorithm
IEEE Geoscience and Remote Sensing Letters, 2007This letter presents a novel calibration approach to polarimetric synthetic aperture radar using distributed targets with known scattering characteristics. A genetic algorithm with complex-valued encoding is proposed to solve the overdetermined system of nonlinear equations associated with the polarimetric calibration problem.
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The GREGOR polarimetric calibration unit
Astronomische Nachrichten, 2012AbstractThe new Solar telescope GREGOR is designed to observe small‐scale dynamic magnetic structures below a size of 70 km on the Sun with high spectral resolution and polarimetric accuracy. For this purpose, the polarimetric concept of GREGOR is based on a combination of post‐focus polarimeters with pre‐focus equipment for high precision calibration.
A. Hofmann +9 more
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Simulated Calibrators Based Polarimetric Weather Radar External Calibration
2020 13th International Congress on Image and Signal Processing, BioMedical Engineering and Informatics (CISP-BMEI), 2020As a potential tool for atmospheric observation, weather radar has shown good performance in providing abundant meteorological data during a short time. The key to use weather radar is that the collected data should have sufficient accuracy. To achieve this purpose, weather radar external calibration technique is proposed and applied for practical data
Jie Yin +5 more
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Calibration of HUT polarimetric radiometer
IGARSS '98. Sensing and Managing the Environment. 1998 IEEE International Geoscience and Remote Sensing. Symposium Proceedings. (Cat. No.98CH36174), 1998The Helsinki University of Technology polarimetric radiometer calibration system is described. Calibration is based on a metal wire grid polarizer and two absorption loads at different temperatures. The characteristics of the grid and the formulae for calibration are presented. The maximum error due calibration is calculated.
J. Lahtinen, M. Hallikainen
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Calibration of polarimetric radar systems
IEEE Antennas and Propagation Society International Symposium 1997. Digest, 2002The calibration of reciprocal radar systems has been studied previously, where it was shown: (1) that full polarimetric calibration of radar systems can remove cross-polarization errors from the measurements, and (2) that for reciprocal radars Fourier analysis of polarimetric data obtained using a rotating dihedral can reduce the noise and background ...
L.A. Muth, R.C. Wittmann
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Calibration Of Polarimetric Radar Systems
12th Canadian Symposium on Remote Sensing Geoscience and Remote Sensing Symposium,, 2005A practical technique is proposed for calibrating single-antenna polarimetric radar systems using a metal sphere plus any second target with a strong cross-polarized radar cross section. It is shown that all magnitudes and phases (relative to one of the like-polarized linear polarization configurations) of the radar transfer function can be calibrated ...
K. Sarabandi, F.T. Ulaby
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A New Approach for Polarimetric Calibration
2006 International Conference on Microwaves, Radar & Wireless Communications, 2006This paper presents a new calibration approach for polarimetric SAR using distributed targets with known scattering matrixes. A genetic algorithm based on complex-valued encoding is used to solve the polarimetric calibration problem, which has multiple variables and over-determined non-linear equations.
Weizu Xiong, Zhongfu Ye
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Transpolarizing surfaces for polarimetric SAR systems calibration
2007 IEEE International Geoscience and Remote Sensing Symposium, 2007A novel transpolarizing or crosspolarizing surface has been proposed to be applied in polarimetric SAR calibrating systems, like trihedrals, since they can not provide initially a crosspolar response. So the trans-surface has been designed and measured in an anechoic chamber, providing good results for normal incidence.
Pere J. Ferrer +6 more
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A new polarimetric active radar calibrator and calibration technique
SPIE Proceedings, 2015Polarimetric active radar calibrator (PARC) is one of the most important calibrators with high radar cross section (RCS) for polarimetry measurement. In this paper, a new double-antenna polarimetric active radar calibrator (DPARC) is proposed, which consists of two rotatable antennas with wideband electromagnetic polarization filters (EMPF) to achieve ...
Jianguo Tang, Xiaojian Xu
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Developing calibration technology for full-polarimetric GPR
2012 IEEE International Geoscience and Remote Sensing Symposium, 2012Polarimetric GPR requires accurate calibration of channel imbalance and crosstalk not only in the amplitude term but also in the phase term. Currently, there have some calibration techniques. Though these techniques are very easy to perform, they provide less accurate calibration results for the crosstalk.
Xuan Feng 0001 +8 more
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