Filters








510 Hits in 3.3 sec

On the Optimal Design of Doppler Scatterometers

Ernesto Rodriguez
2018 Remote Sensing  
Unlike conventional scatterometers or pencil-beam imagers, appropriate sampling of the Doppler spectrum and optimizing the radial velocity error lead naturally to a design that incorporates a pulse-to-pulse  ...  Here, guidelines to optimize the design of these instruments starting from the basic sensitivity equations are presented.  ...  Acknowledgments: The research presented in the paper was carried out at the Jet Propulsion Laboratory,  ... 
doi:10.3390/rs10111765 fatcat:2h6rnsrf3fgrlnnbddrslmqp2q

Tradeoffs in the design of a spaceborne scanning pencil beam scatterometer: application to SeaWinds

M.W. Spencer, Chialin Wu, D.G. Long
1997 IEEE Transactions on Geoscience and Remote Sensing  
An important international element of NASA's earth observing system (EOS), SeaWinds is an advanced follow-on to the NASA scatterometer (NSCAT) on the first ADEOS platform.  ...  First, the overall SeaWinds functional design and backscatter measurement approach are described, and the relative advantages of the pencil-beam technique are outlined.  ...  Although we have concentrated on the specific SeaWinds design, it is hoped that the design issues and trade-offs discussed will be of general utility for other spaceborne scatterometers.  ... 
doi:10.1109/36.551940 fatcat:i2zkwvxpcbaupht4pnwvk6xiae

Multifunctional Scatterometer System for Measuring Physical Oceanographic Parameters Using Range-Doppler FMCW Radar

Ji-Hwan Hwang, Duk-jin Kim, Ki-Mook Kang
2022 Sensors  
A multifunctional scatterometer system and optimized radar signal processing for simultaneous observation of various physical oceanographic parameters are described in this paper.  ...  samples, i.e., the range and backscattering of radar target signals are analyzed from the fast-time samples while the Doppler frequency by the radar target's movement extracts from the slow-time samples  ...  Conflicts of Interest: The authors declare no conflict of interest.  ... 
doi:10.3390/s22082890 pmid:35458877 pmcid:PMC9027241 fatcat:qua5iije5bdwligj2okz4ccvke

Improved resolution backscatter measurements with the SeaWinds pencil-beam scatterometer

M.W. Spencer, C. Wu, D.G. Long
2000 IEEE Transactions on Geoscience and Remote Sensing  
SeaWinds employs a compact "pencil-beam" design rather than the "fan-beam" approach previously used with SASS on Seasat, NSCAT on ADEOS-I, and the AMI scatterometer on ERS-1, 2.  ...  The SeaWinds scatterometer was launched on the NASA QuikSCAT spacecraft in June 1999 and is planned for the Japanese ADEOS-II mission in 2000.  ...  A goal of scatterometer design is the minimization of .  ... 
doi:10.1109/36.823904 fatcat:mcjsddxionehxed7opk7yjmb7q

Vector Current Measurement Using Doppler Scatterometry with Optimally Selected Observation Azimuths

Weifeng Sun, Qing Wang, Weimin Huang, Chenqing Fan, Yongshou Dai
2021 Remote Sensing  
The Doppler scatterometer is a new style of remote sensing tool that can provide current measurements over a wide swath for rapid global coverage.  ...  With the Ocean Surface Current Analyses Real-time (OSCAR) data as current input, vector current estimation experiments were conducted based on simulation analysis using an instrument conceptual design  ...  Acknowledgments: The authors would like to thank the anonymous reviewers for their comments and suggestions that will help to improve the quality of this article.  ... 
doi:10.3390/rs13214263 fatcat:2afvndrf25cutiiyxk25gyzrbm

CFOSAT Rotating Fan‐beam Scatterometer Backscatter Measurement Processing

Risheng Yun, Xiaolong Dong, Jianqiang Liu, Wenming Lin, Di Zhu, Jianying Ma, Shuyan Lang, Zhisen Wang
2021 Earth and Space Science  
Over the last four decades, considerable development of wind scatterometers has been carried out.  ...  Rotating Pencil Beam Scatterometer For the rotating pencil beam scatterometer, the number of views and the azimuth angles vary with the wind vector cell (WVC) number or sub-satellite cross-track position  ...  Acknowledgment The authors would like to thank Cheng Yan of DFH Satellite Co., Ltd, Beijing, China for providing the technical requirements of satellite platform and details of on orbit work.  ... 
doi:10.1029/2021ea001969 fatcat:nhvgdzpm3jc4nl5jy7vzje6tia

Radar backscatter measurement accuracy for a spaceborne pencil-beam wind scatterometer with transmit modulation

D.G. Long, M.W. Spencer
1997 IEEE Transactions on Geoscience and Remote Sensing  
In either case, a key design goal is to optimize the measurement accuracy within the design constraints.  ...  The existence of analytic expressions for permit detailed tradeoffs in the design of spaceborne scatterometer systems.  ...  While at JPL he was the Senior Project Engineer on the NASA Scatterometer (NSCAT) project.  ... 
doi:10.1109/36.551939 fatcat:sdv2lf3arzeethz5ypt4pg33oq

Estimation and Correction of Geolocation Errors of the CFOSAT Scatterometer Using Coastline Backscatter Coefficients

Kuo Zhang, Xiaolong Dong, Di Zhu, Risheng Yun
2020 IEEE Journal of Selected Topics in Applied Earth Observations and Remote Sensing  
In addition, because the geolocation of scatterometer data is affected by terrain, the geolocation errors of CSCAT are corrected based on an elevation correction algorithm using high-precision digital  ...  The accuracy of geolocation has a large impact on the accuracy of wind field retrieval. It is necessary to estimate and analyze the geolocation processing of CSCAT.  ...  The Doppler frequency offset of the fan-beam rotating scanning scatterometer varies with azimuth, elevation, and latitude of the nadir point.  ... 
doi:10.1109/jstars.2020.3035238 fatcat:cnscxs6x3basbc2tcmkfmbko6u

High resolution surface backscatter measurements with the SeaWinds pencil-beam scatterometer

M.W. Spencer, Chialin Wu, D.G. Long
1998 IGARSS '98. Sensing and Managing the Environment. 1998 IEEE International Geoscience and Remote Sensing. Symposium Proceedings. (Cat. No.98CH36174)  
Long, "Tradeoffs in the Design of a Spaceborne Scanning Pencil Beam Scatterometer: Application to Seawinds," IEEE Transactions on Geoscience and Remote Sensing, Vol 35, No. 1, January 1997. [4] C.  ...  One design challenge, largely unanticipated until the success of the recent NSCAT mission, is the coarser spatial resolution of the pencil-beam footprint obtainable with a 1 m parabolic dish as compared  ... 
doi:10.1109/igarss.1998.703718 fatcat:izl3uf55ojcddbxdcz7yqm6zsq

Scientific Developments and the EPS-SG Scatterometer

Ad Stoffelen, Signe Aaboe, Jean-Christophe Calvet, James Cotton, Giovanna De Chiara, Julia Figa Saldana, Alexis Aurelien Mouche, Marcos Portabella, Klaus Scipal, Wolfgang Wagner
2017 IEEE Journal of Selected Topics in Applied Earth Observations and Remote Sensing  
successful advanced scatterometer (ASCAT) flown on the current EPS satellites.  ...  The second-generation exploitation of meteorological satellite polar system (EPS-SG) C-band-wavelength scatterometer instrument (called SCA), planned for launch in 2022, has a direct heritage from the  ...  [65] (quantitatively) show how the ocean current contribution to the Doppler shift can be measured after a careful correction of the sea-state contribution, based on ancillary information on the wind  ... 
doi:10.1109/jstars.2017.2696424 fatcat:agdiglg6wndj3om4chwkeufita

Scatterometer image reconstruction from aperture-filtered samples

Brent A. Williams, David G. Long
2010 2010 IEEE International Geoscience and Remote Sensing Symposium  
Examples from the SeaWinds scatterometer and the Advanced Wind Scatterometer (ASCAT) are presented.  ...  Backscatter imaging is approached as the inversion of a noisy aperturefiltered sampling operation.  ...  where g i = A T i s is the i th noise-free σ 0 measurement, and α, β, and γ are parameters that are a function of the scatterometer design and the measured receiver noise power [3] .  ... 
doi:10.1109/igarss.2010.5654148 dblp:conf/igarss/WilliamsL10 fatcat:mftiwjwzfzex7jegvzq3nxf7sm

The Winds and Currents Mission Concept

Ernesto Rodríguez, Mark Bourassa, Dudley Chelton, J. Thomas Farrar, David Long, Dragana Perkovic-Martin, Roger Samelson
2019 Frontiers in Marine Science  
WaCM features a Ka-band pencil-beam Doppler scatterometer able to map ocean winds and currents globally. We review the principles behind the WaCM measurement and the requirements driving the mission.  ...  The Winds and Currents Mission (WaCM) is a proposed approach to meet the need identified by the NRC Decadal Survey for the simultaneous measurements of ocean vector winds and currents.  ...  ACKNOWLEDGMENTS The research was partially carried out at the Jet Propulsion Laboratory, California Institute of Technology, under a contract with the National Aeronautics and Space Administration (80NM0018D0004  ... 
doi:10.3389/fmars.2019.00438 fatcat:z4bvmu7csrfu7ouzd5uyaup6mi

ANALYZING EFFECTS OF SATELLITE ATTITUDE AND SPEED ERRORS ON OCEAN CURRENT RETRIEVAL FOR A DOPPLER SCATTEROMETER

Yuanjing Miao, Xiaolong Dong, Di Zhu
2021 Progress In Electromagnetics Research M  
Our results confirm the importance of satellite attitude determination accuracy for future ocean current mission and will also be useful to motivate the design of future Doppler measurement instruments  ...  Geometrical Doppler shift induced by satellite movement is highly dependent on the accuracies of satellite attitude determinations and speed.  ...  The coordinate of P point that Doppler scatterometer observes is (H tan θ cos φ, H tan θ sin φ, H) T .  ... 
doi:10.2528/pierm21080601 fatcat:wpfz77np2bbyzm3eo36mmmtpyi

Measuring Winds and Currents with Ka-Band Doppler Scatterometry: An Airborne Implementation and Progress towards a Spaceborne Mission

Alexander Wineteer, Dragana Perkovic-Martin, Raquel Monje, Ernesto Rodríguez, Tamás Gál, Noppasin Niamsuwan, Fabien Nicaise, Karthik Srinivasan, Chad Baldi, Ninoslav Majurec, Bryan Stiles
2020 Remote Sensing  
Doppler scatterometry is a coherent burst-scatterometry technique that builds on the long heritage of spinning pencil beam scatterometers to enable the wide-swath, simultaneous measurement of ocean surface  ...  This paper summarizes the development of DopplerScatt hardware, systems, calibration, and operations, and how advances in each relate to progress towards a spaceborne Doppler scatterometer mission.  ...  Copyright 2020 California Institute of Technology. US government sponsorship acknowledged. Conflicts of Interest: The authors declare no conflicts of interest.  ... 
doi:10.3390/rs12061021 fatcat:3vr3wrggdzcp7m4zatibw6lzbm

Doppler Navigation System with a Non-Stabilized Antenna as a Sea-Surface Wind Sensor

Alexey Nekrasov, Alena Khachaturian, Vladimir Veremyev, Mikhail Bogachev
2017 Sensors  
We propose a concept of the utilization of an aircraft Doppler Navigation System (DNS) as a sea-surface wind sensor complementary to its normal functionality.  ...  We consider the wind measurements by the DNS configured in the multi-beam scatterometer mode for a rectilinear flight scenario.  ...  Conflicts of Interest: The authors declare no conflict of interest.  ... 
doi:10.3390/s17061340 pmid:28598374 pmcid:PMC5492284 fatcat:i34rtl6wsjgjdbijmgq3xv3d6a
« Previous Showing results 1 — 15 out of 510 results