Name
Abstract | ||
|---|---|---|
Measuring ocean mesoscale variability is one of the main objectives of next generation satellite altimeters. Current radar altimeters make observations only at the nadir sub-satellite ground track, which is not sufficient to sample the ocean surface with the required spatial and temporal sampling. The GNSS-R concept has been proposed as an alternative observation system in order to overcome this limitation, since it allows performing altimetry along several points simultaneously over a very wide swath. Latest proposed GNSS-R altimeter configurations allow measuring sea height with an accuracy of few decimeters over spatial scales of 50-100 km, by means of a single-pass. This paper proposes an innovative processing and retracking concept for GNSS-R altimeters based on the acquisition of the full delay-Doppler map (DDM), which allows to acquire multiple waveforms at different Doppler frequencies, whose footprints are located outside the typical pulse-limited region. The proposed processing adapts the Synthetic Aperture Radar (SAR) delay-Doppler concept of spaceborne radar altimeters for use in a GNSS-R system. This processing yields additional multi-look with respect to conventional GNSS-R concepts and translates into an improvement of the altimetry performance estimated to be at least 25%-30%, and even higher, depending on the wanted along-track spatial resolution. The proposed processing can also provide measurements with high spatial resolution at best possible performance, and more generally, offers various possibilities for optimal trade-off between spatial-resolution and height estimation accuracy. |
Year | DOI | Venue |
|---|---|---|
2014 | 10.1109/JSTARS.2014.2309352 | Selected Topics in Applied Earth Observations and Remote Sensing, IEEE Journal of |
Keywords | Field | DocType |
doppler radar,oceanographic techniques,radar altimetry,remote sensing by radar,satellite navigation,sea level,spaceborne radar,synthetic aperture radar,doppler frequencies,doppler multilooking,gnss-r altimeter configurations,gnss-r concept,gnss-r system,along-track spatial resolution,altimetry performance,delay-doppler map,height estimation accuracy,high spatial resolution,multiple waveforms,nadir subsatellite ground track,next-generation satellite altimeters,observation system,ocean mesoscale variability,ocean surface,pulse-limited region,retracking concept,sea height,spaceborne radar altimeters,spatial sampling,spatial scales,synthetic aperture radar delay-doppler concept,temporal sampling,delay-doppler altimetry,gnss reflectometry,paris concept,ocean altimetry,global positioning system,altimetry,gps signals,spatial resolution,system,antennas,doppler effect,radar altimeter,surface | Radar,Nadir,GNSS reflectometry,Altimeter,Synthetic aperture radar,Remote sensing,Ground track,Radar altimeter,GNSS applications,Geodesy,Mathematics | Journal |
Volume | Issue | ISSN |
7 | 5 | 1939-1404 |
Citations | PageRank | References |
4 | 0.52 | 10 |
Authors | ||
5 | ||
Name | Order | Citations | PageRank |
|---|---|---|---|
| Salvatore D'Addio | 1 | 139 | 18.08 |
| Manuel Martin-Neira | 2 | 524 | 51.78 |
| di Bisceglie, M. | 3 | 59 | 13.69 |
| Carmela Galdi | 4 | 44 | 11.30 |
| f alemany | 5 | 4 | 0.52 |