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Cramer-Rao Bounds For Radar Altimeter Waveforms

Corinne Mailhes, Jerome Severini, Pierre Thibaut, J.-Y. Tourneret
2008 Zenodo  
CONCLUSIONS This paper derived Cramér-Rao lower bounds for the parameters of radar altimeter waveforms. These bounds have been obtained by assuming the altimetric signals satisfy Brown's model.  ...  CRAMÉR-RAO BOUNDS The likelihood defined in (4) is denoted as f for brevity.  ... 
doi:10.5281/zenodo.40949 fatcat:bpbgxqf3azdqljyi246ufaqb74

SAR Altimetry Applications over Water [article]

C. Martin-Puig, J. Marquez, G. Ruffini, R.K. Raney, J. Benveniste
2008 arXiv   pre-print
To this end, theoretical modelling using the Cramer-Rao bound (CRB) will be used and the results will be compared to previous theoretical estimates [7], using an analysis akin to that in [8].  ...  The application of Synthetic Aperture Radar (SAR) techniques to classical radar altimetry offers the potential for greatly improved Earth surface mapping.  ...  To determine the precision of reduced SAR compared to a conventional altimeter we will make use of estimation theory, i.e., we will analyse the Cramér-Rao bound.  ... 
arXiv:0802.0804v1 fatcat:yfidfbeumzeavjsfug47q7u53e

Cramér-Rao Bounds And Estimation Algorithms For Delay/Doppler And Conventional Altimetry

Abderrahim Halimi, Corinne Mailhes, J.-Y. Tourneret
2013 Zenodo  
Comparison between CA and DDA Estimation performance for DDA CONCLUSIONS This paper derived the Cramér-Rao lower bounds for the parameters of the double convolution model for radar altimetry.  ...  The first contribution of this paper is the derivation of the Cramér-Rao bounds (CRBs) of the parameters associated with the semi-analytic delay/Doppler altimetric model.  ... 
doi:10.5281/zenodo.43524 fatcat:5hlgrbppjjf6pccpkhhthbqdr4

A Waveform Model for Near-Nadir Radar Altimetry Applied to the Cassini Mission to Titan

G. Alberti, L. Festa, C. Papa, G. Vingione
2009 IEEE Transactions on Geoscience and Remote Sensing  
The radar altimeter of the Cassini mission to Titan operates in a transition region between pulse-and beam-limited conditions.  ...  An analytical model of the average return power waveform, valid for near-nadir altimetry measurements, has been developed in order to cope with the particular operating conditions of Cassini mission.  ...  During last year, the authors participated with the Cassini Altimetry Working Group, which has made great efforts for the assessment of processing algorithms for the retrieval of Titan's surface height  ... 
doi:10.1109/tgrs.2009.2012718 fatcat:yfqzgl55nbbwxlxwtnuvbfsxse

DopSCA, Scatterometer-based Simultaneous Ocean Vector Current and Wind Estimation

Peter Hoogeboom, Ad Stoffelen, Paco Lopez-Dekker
2018 2018 Doppler Oceanography from Space (DOfS)  
Generation) SCA of Eumetsat are not designed to measure ocean currents, yet if they could, it would improve the wind vector product and provide important additional information to the oceanographic community for  ...  This is in agreement with the 0.61 m/s value from the Cramér-Rao bound calculation (which was calculated for 15 looks). However this precision is in the radar range direction.  ...  Consequently the Cramér-Rao bound indicates a best ocean speed accuracy of 0.61 m/s for the 50 x 50 km WVC. This is in range direction.  ... 
doi:10.1109/dofs.2018.8587276 fatcat:lyzvi76n2fb7tfabbijvwxaiue

Fading statistics and sensing accuracy of ocean scattered GNSS and altimetry signals

Scott Gleason, Christine Gommenginger, David Cromwell
2010 Advances in Space Research  
Additionally, in assessing the potential of using GNSS-R signals for ocean remote sensing, it is useful to compare the signal characteristics with those of existing radar altimeter instruments.  ...  This paper starts with a brief review of scattering statistics theory for diffusely scattered radar signals.  ...  The minimum standard deviations will be limited by the Cramer-Rao lower bound, determined by the minimum achievable variance of the signal noise over the longest allowable incoherent averaging interval  ... 
doi:10.1016/j.asr.2010.03.023 fatcat:fgacurimlvfghhusa2x3punufi

Potential Accuracy of Echo-Signal Delay Measurement by Space-Based Radar Altimeter

D. S. Borovitsky, A. E. Zhesterev, V. P. Ipatov, R. M. Mamchur
2017 Journal of the Russian Universities Radioelectronics  
The Cramer-Rao bound defines the dependence of potential delay estimate accuracy on power and spectral resources used by altimeter, and the form of received power profile.  ...  Satellite radar altimetry is a universal tool for global all-weather monitoring of the surface of the Earth.  ... 
doaj:37da4c4da9f444438e6b312f8c560b96 fatcat:3uvaa7zg25eutlzsebuhhddb4i

The Impact of Inter-Modulation Components on Interferometric GNSS-Reflectometry

Weiqiang Li, Antonio Rius, Fran Fabra, Manuel Martín-Neira, Estel Cardellach, Serni Ribó, Dongkai Yang
2016 Remote Sensing  
The interferometric Global Navigation Satellite System Reflectometry (iGNSS-R) exploits the full spectrum of the transmitted GNSS signal to improve the ranging performance for sea surface height applications  ...  In [17, 28] , comprehensive models were proposed based on the Cramer-Rao Bound (CRB).  ...  As in traditional radar altimeters (RA), the delay of the return echo from the sea surface is the primary observable in GNSS-R altimetry, and its accuracy increases with the signal-to-noise ratio (SNR)  ... 
doi:10.3390/rs8121013 fatcat:owrswdm4yreixeje3bvawv6cdm

Exploiting Time And Frequency Information For Delay/Doppler Altimetry

Francois Boy, Abderrahim Halimi, Corinne Mailhes, Thomas Moreau, J.-Y. Tourneret
2014 Zenodo  
Prospects include the derivation of Cramér-Rao lower bounds associated with the proposed delay/Doppler model.  ...  the same normalized waveforms.  ... 
doi:10.5281/zenodo.43918 fatcat:3oqs2ruqa5bgppklgdna72lgjm

GNSS-R Altimetry Performance Analysis for the GEROS Experiment on Board the International Space Station

Adriano Camps, Hyuk Park, Ivan Sekulic, Juan Rius
2017 Sensors  
In the absence of ionospheric scintillations, the altimetry rms error is <50 cm for a swath <~250 km and for U 10 <10 m/s.  ...  If the transmitted power is 3 dB higher (likely to happen at beginning of life of the GNSS spacecrafts), mission requirements (rms error is <50 cm) are met for all ISS heights and for U 10 up to 15 m/s  ...  Cramér-Rao bound (CRB) (Equation (1)), which is expressed here in the timedomain and discrete form [3] : 2 ≥ 1 ∑ , −1 ′ − ′ − , (1) where ̿ is the covariance matrix of the waveform ( ), and ′ is the waveform's  ... 
doi:10.3390/s17071583 pmid:28684724 pmcid:PMC5539822 fatcat:3tfvi2q5jrdldfjomtuijcfwe4

Measurement of the Sea Surface Height with Airborne GNSS Reflectometry and Delay Bias Calibration

Feng Wang, Dongkai Yang, Guodong Zhang, Jin Xing, Bo Zhang, Lei Yang
2021 Remote Sensing  
The arrival time of a feature point, such as the waveform peak, the peak of the derivative waveform, and the fraction of the peak waveform is not the true arrival time of the specular signal; there is  ...  Based on the fact that the specular points of several satellites are visible to the down-looking antenna, the multi-observation method is proposed to calibrate the bias for the case of unknown wind speed  ...  Lopez-Baeza at Valencia University for the improvements to the manuscript.  ... 
doi:10.3390/rs13153014 fatcat:kwen6r76nvhydhodhj2bk3jrry

ALTIMETRY BY CASSINI RADAR: PROCESSING AND SIMULATION

Giovanni Alberti
2009
The Radar Altimeter of the Cassini Mission to Titan operates in a transition region between pulse and beam-limited condition.  ...  An analytical model of the average return power waveform, valid for near-nadir altimetry measurements, has been developed in order to cope with the particular operating conditions of Cassini Mission.  ...  The actual performance of the implemented method can be evaluated via simulation, since the Cramer-Rao bound can give optimistic values in this case.  ... 
doi:10.6092/unina/fedoa/3825 fatcat:lwcoczgbcre5jd73hutu3w22ky

GEROS-ISS: GNSS REflectometry, Radio Occultation, and Scatterometry Onboard the International Space Station

Jens Wickert, Estel Cardellach, Manuel Martin-Neira, Jorge Bandeiras, Laurent Bertino, Ole Baltazar Andersen, Adriano Camps, Nuno Catarino, Bertrand Chapron, Fran Fabra, Nicolas Floury, Giuseppe Foti (+19 others)
2016 IEEE Journal of Selected Topics in Applied Earth Observations and Remote Sensing  
GEROS-ISS stands for GNSS REflectometry, radio occultation, and scatterometry onboard the International Space Station (ISS).  ...  The main focus of GEROS-ISS is the dedicated use of signals from the currently available Global Navigation Satellite Systems (GNSS) in L-band for remote sensing of the Earth with a focus to study climate  ...  The error budget was later improved by computing the Cramer-Rao bound (CRB, [25] ). Fig. 9 shows the computed performance for the Galileo signals.  ... 
doi:10.1109/jstars.2016.2614428 fatcat:7zfmpvdb2fhu3aj5wfcvwwghza

Synthetic aperture radar interferometry

P.A. Rosen, S. Hensley, I.R. Joughin, F.K. Li, S.N. Madsen, E. Rodriguez, R.M. Goldstein
2000 Proceedings of the IEEE  
Synthetic aperture radar interferometry is an imaging technique for measuring the topography of a surface, its changes over time, and other changes in the detailed characteristics of the surface.  ...  By exploiting the phase of the coherent radar signal, interferometry has transformed radar remote sensing from a largely interpretive science to a quantitative tool, with applications in cartography, geodesy  ...  Calder, Managing Editor of this PROCEEDINGS, for accommodating them. They are also extremely grateful to the four reviewers who gave their time to help them to fashion a balanced review.  ... 
doi:10.1109/5.838084 fatcat:p6htog22o5hb5foaou5ax3pt4a

Using the future L-band communication system for navigation

Michael Schnell, Ulrich Epple, Felix Hoffmann
2011 2011 Integrated Communications, Navigation, and Surveillance Conference Proceedings  
In this paper, we propose to apply the future Lband digital aeronautical communication system not only for communications but also for navigation purposes.  ...  as fallback solution for satellite-based navigation.  ...  A measure for the accuracy of this approach is the variance of the timing estimate τ . The maximum achievable performance for this variance can be given by the Cramer-Rao Lower Bound (CRLB).  ... 
doi:10.1109/icnsurv.2011.5935294 fatcat:2jyez7ecofhizfpnfeb5bbelci
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