Airborne GNSS reflectometry for coastal monitoring of sea state
| Autor: | Mario Moreno |
|---|---|
| Jazyk: | English<br />Spanish; Castilian<br />French<br />Portuguese |
| Rok vydání: | 2024 |
| Předmět: | |
| Zdroj: | Revista Cartográfica, Iss 108 (2024) |
| Druh dokumentu: | article |
| ISSN: | 0080-2085 2663-3981 |
| DOI: | 10.354242/rcarto.i108.4524 |
| Popis: | Sea level rise and sea state variability, resulting from climate change and global warming, are critical research areas. However, current techniques for observing and monitoring these phenomena have limitations in terms of spatial and temporal resolution, particularly in dynamic coastal zones. GNSS Reflectometry (GNSS-R) is an emerging bistatic radar-based technique that utilizes the GNSS direct (transmitter-receiver) and reflected (transmitter-reflection point-receiver) signals to extract properties of the reflecting surface. This study explores the potential of airborne GNSS-R as a means to monitor sea state in coastal areas by using the Doppler spread and reflectivity as observables. The paper aims to derive a sea state factor from the reflected signal power and the Doppler shift distribution to analyze its correlation with wind speed and significant wave height data obtained from the ERA5 model. The experiment involved four flights conducted along the coast between Calais and Boulogne-sur-Mer, France, in July 2019. A GNSS software receiver processes the direct and reflected signals, tracking and re-tracking the reflected signals with the aid of a specular reflection model. The resulting in-phase and quadrature components are analyzed in the spectral domain every minute to estimate the power, the surface reflectivity, and the relative Doppler shift. The findings reveal that the sea state factor and Doppler spreading are sensitive to sea state conditions, correlated with the ERA5 parameters, and influenced by the elevation angle of GNSS satellites. At low elevations (E |
| Databáze: | Directory of Open Access Journals |
| Externí odkaz: |
|