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In-orbit Calibration and Validation of HY-2B Altimeter Using an Improved Transponder

Caiyun Wang, Mingsen Lin, Chaofei Ma, Ke Xu, Peng Liu, Te Wang, Bo Mu, Jinbiao Zhu, Wei Guo
2021 IEEE Journal of Selected Topics in Applied Earth Observations and Remote Sensing  
The purpose of the paper is to describe the in-orbit calibration and validation of HY-2B altimeter based on an improved transponder.  ...  For the altimeter, an in-orbit calibration mode was designed to achieve higher calibration precision. An improved transponder was built and deployed for the calibration campaign.  ...  bias. range d is the measured range to the transponder, including ionosphere delay, atmosphere delay, etc. orbit d is the geometric distance from the satellite gravity center to the transponder  ... 
doi:10.1109/jstars.2021.3111922 fatcat:oy2sku6qijdfxl35gtyx76gcmu

The ESA Permanent Facility for Altimetry Calibration: Monitoring Performance of Radar Altimeters for Sentinel-3A, Sentinel-3B and Jason-3 Using Transponder and Sea-Surface Calibrations with FRM Standards

Stelios Mertikas, Achilleas Tripolitsiotis, Craig Donlon, Constantin Mavrocordatos, Pierre Féménias, Franck Borde, Xenophon Frantzis, Costas Kokolakis, Thierry Guinle, George Vergos, Ilias N. Tziavos, Robert Cullen
2020 Remote Sensing  
External and independent calibration and validation facilities provide an objective assessment of the altimeter's performance by comparing satellite observations with ground-truth and in-situ measurements  ...  Three independent methods are employed in the PFAC: Range calibration using a transponder, sea-surface calibration relying upon sea-surface Cal/Val sites, and crossover analysis.  ...  Acknowledgments: We thank very much the three reviewers and the editor for their excellent and meticulous comments and observations made on this manuscript.  ... 
doi:10.3390/rs12162642 fatcat:sv5uytkopvfmzh6fvtonjcrgzu

Improvement of orbit determination for geostationary satellites with VLBI tracking

Yong Huang, XiaoGong Hu, XiuZhong Zhang, DongRong Jiang, Rui Guo, Hong Wang, ShanBin Shi
2011 Chinese Science Bulletin  
In contrast to ranging, which measures distances between a GEO satellite and an observer, VLBI is an angular measurement technique that constrains the satellite's position errors perpendicular to the satellite-to-observer  ...  As a demonstration, the Chinese VLBI Network organized a tracking and orbit-determination experiment for a GEO navigation satellite lasting 24 h.  ...  The authors would like to thank the CVN  ... 
doi:10.1007/s11434-011-4647-0 fatcat:4ihomgstuvfyjkbpz7apfgjzza

Fifteen Years of Cal/Val Service to Reference Altimetry Missions: Calibration of Satellite Altimetry at the Permanent Facilities in Gavdos and Crete, Greece

Stelios Mertikas, Craig Donlon, Pierre Féménias, Constantin Mavrocordatos, Demitris Galanakis, Achilles Tripolitsiotis, Xenophon Frantzis, Ilias Tziavos, George Vergos, Thierry Guinle
2018 Remote Sensing  
Absolute calibration of altimeters is achieved by external and independent to satellite facilities on the ground.  ...  This is the mainstay for a continuous, homogenous, and reliable monitoring of the earth and its oceans.  ...  We greatly thank Joana Fernandes and Telmo Vieira, University of Porto, Portugal, for helping us better understand the wet troposphere delays and for verifying the produced results.  ... 
doi:10.3390/rs10101557 fatcat:mqamyypi2jb37jvlmk6ptuzmru

One-Way Time Synchronization via Geostationary Satellites at UHF

D. Wayne Hanson, Wallace F. Hamilton
1971 IEEE Transactions on Instrumentation and Measurement  
Orbital elements dedescriptions of the equipment, timing signal format, and methods scribe the satellite's orbit and position in that orbit at a for delay calculation and time recovery. given instant of  ...  measurement could improve the results for TACSAT to earth synchronous satellites and path delays derived 75 Ms.  ...  The authors are with the Frequency-Time. .Dissemin.ation most readily appjarent, the observing sites were dispersed Research Section, Time and Frequency Division, National Bureau of Standards, Boulder,  ... 
doi:10.1109/tim.1971.5570716 fatcat:w3wkkijv7rdqzcwou35yc5i2nq

Spaceborne SAR product geolocation accuracy: A Sentinel-1 update

Adrian Schubert, David Small, Erich Meier, Nuno Miranda, Dirk Geudtner
2014 2014 IEEE Geoscience and Remote Sensing Symposium  
As of the end of May, 2014, the satellite has not yet reached its reference orbit. However, estimation of product geolocation accuracy is ongoing, and improvements are continually being made.  ...  Sentinel-1A (S1A), launched by the European Space Agency (ESA) on April 3, 2014, is a state-of-the-art spaceborne Synthetic Aperture Radar (SAR) Earth observation platform.  ...  An overview of the methods used to mitigate these influences is given in [6] .  ... 
doi:10.1109/igarss.2014.6947025 dblp:conf/igarss/SchubertSMMG14 fatcat:hdawmhpts5hhtmztxm5krvrode

Design of Wideband Output Filter Based on Requirements for 21-GHz Band Satellite Broadcasting

Yoshifumi MATSUSAKI, Akinori HASHIMOTO, Masafumi NAGASAKA, Yoichi SUZUKI, Susumu NAKAZAWA, Masashi KAMEI, Shoji TANAKA, Takeshi KIMURA, Yasuhiro ITO
This paper presents the requirement specifications for an output filter for a 21-GHz band broadcasting satellite system and shows simulation results of the characteristics of the filter.  ...  Considering this system, the output filter was designed for a linear frequency response and low in-band group delay, and sufficient suppression of interference from adjacent bands such as the radio astronomy  ...  Acknowledgments This research and development is being performed under the auspices of "Research and Development of Technology Encouraging Effective Utilization of Frequency for the Next Generation Satellite  ... 
doi:10.2322/tastj.12.tj_1 fatcat:orih4mmpgjempejrp2txxehv34

Absolute Calibration of the European Sentinel-3A Surface Topography Mission over the Permanent Facility for Altimetry Calibration in west Crete, Greece

Stelios Mertikas, Craig Donlon, Pierre Féménias, Constantin Mavrocordatos, Demitris Galanakis, Achilles Tripolitsiotis, Xenophon Frantzis, Costas Kokolakis, Ilias Tziavos, George Vergos, Thierry Guinle
2018 Remote Sensing  
An uncertainty analysis for the altimeter biases derived by the transponder and by sea-surface calibrations is also introduced following the new standard of Fiducial Reference Measurements.  ...  The groundtrack of the Pass No.14 of Sentinel-3A ascends west of the Gavdos island and continues north to the transponder site on the mountains of west Crete.  ...  Many thanks to Joana Fernandes and Telmo Vieira, University of Porto, Portugal, for helping us better understand the wet troposphere delays and for verifying the produced results.  ... 
doi:10.3390/rs10111808 fatcat:ha723kjvrjf3tbe27fnxeot2iu

Inverse VLBI Method for Planetodesy

Nobuyuki Kawano, Mizuhiko Hosokawa, Hideo Hanada, Michito Imae
1999 Journal of the Geodetic Society of Japan  
A new method for geodetic observations of a planet is proposed. Synchronized radio  ...  on an up-link and a down-link for the landing unit i, and the instrumental delay of the orbiter and the landing unit respectively.  ...  VLBI, which are not enough accuracies to measure the characteristics of a celestial body mentioned before. 2-way Doppler frequency measurements between an orbiter and transponders on the Mars are programmed  ... 
doi:10.11366/sokuchi1954.45.181 fatcat:onqqtzrmpvbklbmcqp3wkz2nq4


İbrahim ÖZ, Ümit Cezmi YILMAZ, Ümit GÜLER
2022 Eskişehir Technical University Journal of Science and Technology A - Applied Sciences and Engineering  
The satellite operators need the current and future motion of the satellites for operational purposes and use various methods to measure the tracking data.  ...  The satellite operators can utilize the proposed TDOA measurement method with its benefits to estimate satellite orbit.  ...  CONFLICT OF INTEREST The authors stated that there are no conflicts of interest regarding the publication of this article.  ... 
doi:10.18038/estubtda.993185 fatcat:hnncityikjbh5gi2vmz4a3xlgu

The Short-Arc Precise Orbit Determination of GEO Satellites Using VLBI and Transfer Ranging

Kai Nan, Fen Cao, Jianjun Gong, Hui Lei, Zhigang Li, Xuhai Yang
2022 Remote Sensing  
Based on orbit determination by transfer tracking (ODTT), the POD accuracy of a GEO satellite is less than 10 m over a short arc.  ...  It is important for a geostationary Earth orbit (GEO) satellite to rapidly recover its orbit after a maneuver with short-arc precise orbit determination (POD).  ...  Conflicts of Interest: The authors declare no conflict of interest.  ... 
doi:10.3390/rs14071572 fatcat:wjwfoctb3fhe5dzojca2ukm74q

Geometric calibration of ERS satellite SAR images

J.J. Mohr, S.N. Madsen
2001 IEEE Transactions on Geoscience and Remote Sensing  
A descending and an ascending orbit tandem pair of the ESA calibration site on Flevoland, suitable for calibration of ERS SAR processors, is described to allow other researchers to geometrically calibrate  ...  The resulting accuracy of the slant range images corresponds to 10 m horizontally on the ground.  ...  The estimation noise and , assumed common for all interferograms, describes the consistency of the transponder measurements in one SLC image.  ... 
doi:10.1109/36.917909 fatcat:5jmriheuufdh5dvz6fqapuzfma

An Action Plan Towards Fiducial Reference Measurements for Satellite Altimetry

Mertikas, Donlon, Vuilleumier, Cullen, Féménias, Tripolitsiotis
2019 Remote Sensing  
FRM4ALT has been introduced and implemented by the European Space Agency in an effort to reach a uniform and absolute standardization for calibrating satellite altimeters.  ...  In line with the above, the strategy of the Fiducial Reference Measurements for Altimetry (FRM4ALT) has been introduced to address and to achieve reliable, long-term, consistent, and undisputable satellite  ...  Acknowledgments: This work has been primarily supported and funded by the European Union, the European Space Agency. Conflicts of Interest: The authors declare no conflict of interest.  ... 
doi:10.3390/rs11171993 fatcat:d2clgtjuoncvzlyfwu4qqviooe

Optimal approach for building scheduling algorithm in satellite communication

Ali M. Al-Saegh
2018 International Journal of Engineering & Technology  
This paper presents efficient approach for accumulating the effective considerations that the designer should employ as a framework for building proper and efficient scheduling algorithm.  ...  The proposed approach provides proper solutions to the satellite communications impairments and satisfies the quality of service requirements in satellite communication networks.  ...  There exist three types of satellite orbits, namely the Geostationary Earth Orbit (GEO), Medium Earth Orbit (MEO), and Low Earth orbit (LEO).  ... 
doi:10.14419/ijet.v7i2.28.12907 fatcat:lesmdicamzg2ln4qtthopoxjkq

International Time Comparison by TWSTFT and GPS at KRISS

Sang-wook Hwang, Chang Bok Lee, Jong Koo Lee, Young Kyu Lee, Sang Jeong Lee, Sung-hoon Yang
2016 Journal of Positioning Navigation and Timing  
ACKNOWLEDGMENTS We appreciate the cooperation of participant institutes on TWSTFT Asia link: NICT and TL.  ...  R refers to satellite Table 1 . 1 Properties of measurements for time comparison methods.  ...  An uplink frequency for two-way communication with a communication satellite is 12.040250 GHz, which is transmitted using horizontal polarization and a transponder of the communication satellite receiving  ... 
doi:10.11003/jpnt.2016.5.2.067 fatcat:gcwkqj2llfbipoip45gj3r7moq
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