RSLAB - Remote Sensing Research Group
http://hdl.handle.net/2117/1442
2024-03-29T00:23:45ZImpact of incidence angle diversity on SMOS and sentinel-1 soil moisture retrievals at coarse and fine scales
http://hdl.handle.net/2117/387275
Impact of incidence angle diversity on SMOS and sentinel-1 soil moisture retrievals at coarse and fine scales
Portal González, Gerard; Vall-Llossera Ferran, Mercedes Magdalena; Piles Guillem, María; Jagdhuber, Thomas; Camps Carmona, Adriano José; Pablos Hernández, Miriam; López Martínez, Carlos; Das, Narendra; Entekhabi, Dara
Incidence angle diversity of space-borne radiometer and radar systems operating at low microwave frequencies needs to be taken into consideration to accurately estimate soil moisture (SM) across spatial scales. In this study, the single channel algorithm (SCA) is first applied to Soil Moisture and Ocean Salinity (SMOS) brightness temperatures at vertical polarization ( TBV ) to estimate SM at coarse resolution (25 km) and develop a land cover-specific and incidence angle (32.5°, 42.5°, and 52.5°)-adaptive calibration of single scattering albedo ( ¿ ) and soil roughness ( hs ) parameters. These effective parameters are used together with fine-scale multiangular Sentinel-1 backscatter in a single-pass active–passive downscaling approach to estimate TBV at fine scale (1 km) for each SMOS incidence angle. These TBVs are finally inverted to obtain the corresponding high-resolution SM maps. Results over the Iberian Peninsula for year 2018 show an increasing trend of ¿ and a decreasing trend of hs with SMOS incidence angle, with almost no variability of ¿ across land cover types. The active–passive covariation parameter is shown to increase with SMOS incidence angle and decrease with Sentinel-1 incidence angle. Coarse and fine TBV maps from the three SMOS incidence angles show similar distributions (mean differences below 0.38 K). Resulting high-resolution SM maps have maximum differences in mean and standard deviation of 0.016 and 0.015 m 3 /m 3 , respectively, and compare well with in situ measurements. Our results indicate that model-based microwave approaches to estimate SM can be adequately adapted to account for the incidence angle diversity of planned missions, such as Copernicus Microwave Imaging Radiometer (CIMR), Radar Observing System for Europe in L-band (ROSE-L), and Sentinel-1 next generation.
2023-05-10T15:30:30ZPortal González, GerardVall-Llossera Ferran, Mercedes MagdalenaPiles Guillem, MaríaJagdhuber, ThomasCamps Carmona, Adriano JoséPablos Hernández, MiriamLópez Martínez, CarlosDas, NarendraEntekhabi, DaraIncidence angle diversity of space-borne radiometer and radar systems operating at low microwave frequencies needs to be taken into consideration to accurately estimate soil moisture (SM) across spatial scales. In this study, the single channel algorithm (SCA) is first applied to Soil Moisture and Ocean Salinity (SMOS) brightness temperatures at vertical polarization ( TBV ) to estimate SM at coarse resolution (25 km) and develop a land cover-specific and incidence angle (32.5°, 42.5°, and 52.5°)-adaptive calibration of single scattering albedo ( ¿ ) and soil roughness ( hs ) parameters. These effective parameters are used together with fine-scale multiangular Sentinel-1 backscatter in a single-pass active–passive downscaling approach to estimate TBV at fine scale (1 km) for each SMOS incidence angle. These TBVs are finally inverted to obtain the corresponding high-resolution SM maps. Results over the Iberian Peninsula for year 2018 show an increasing trend of ¿ and a decreasing trend of hs with SMOS incidence angle, with almost no variability of ¿ across land cover types. The active–passive covariation parameter is shown to increase with SMOS incidence angle and decrease with Sentinel-1 incidence angle. Coarse and fine TBV maps from the three SMOS incidence angles show similar distributions (mean differences below 0.38 K). Resulting high-resolution SM maps have maximum differences in mean and standard deviation of 0.016 and 0.015 m 3 /m 3 , respectively, and compare well with in situ measurements. Our results indicate that model-based microwave approaches to estimate SM can be adequately adapted to account for the incidence angle diversity of planned missions, such as Copernicus Microwave Imaging Radiometer (CIMR), Radar Observing System for Europe in L-band (ROSE-L), and Sentinel-1 next generation.Study of land surface temperature anomalies associated to earthquakes using GOES data
http://hdl.handle.net/2117/387185
Study of land surface temperature anomalies associated to earthquakes using GOES data
Boudriki Semlali, Badr Eddine; Molina Ordóñez, Carlos; Hyuk, Park; Camps Carmona, Adriano José
Annually, earthquakes cause human and material losses. For instance, between 1998 and 2018, 846 thousand deaths and about US$ 661 billion of economic losses were recorded due to earthquakes. Currently, there is no clear precursor to forecast earthquakes. However, numerous investigations have attempted to find precursor proxies based on Land Surface Temperature (LST) anomalies. In this study, a big database collected from GOES/ABI instrument during the full year 2020 has been used to calculate the LST anomalies in the earthquakes zones. A total of 1350 earthquakes of Mw = 4 were studied in 2020. Two methods commonly used in the literature, the interquartile method, and the standard deviation of the time series, have been applied to detect LST anomalies. The confusion matrix, some figures of merit, and the receiver operating characteristic curve have been used to evaluate and enhance the performance of the methods and choose the optimum decision threshold. A positive anomaly is usually found before the earthquakes, followed by an LST decrease after the event.
2023-05-08T16:42:00ZBoudriki Semlali, Badr EddineMolina Ordóñez, CarlosHyuk, ParkCamps Carmona, Adriano JoséAnnually, earthquakes cause human and material losses. For instance, between 1998 and 2018, 846 thousand deaths and about US$ 661 billion of economic losses were recorded due to earthquakes. Currently, there is no clear precursor to forecast earthquakes. However, numerous investigations have attempted to find precursor proxies based on Land Surface Temperature (LST) anomalies. In this study, a big database collected from GOES/ABI instrument during the full year 2020 has been used to calculate the LST anomalies in the earthquakes zones. A total of 1350 earthquakes of Mw = 4 were studied in 2020. Two methods commonly used in the literature, the interquartile method, and the standard deviation of the time series, have been applied to detect LST anomalies. The confusion matrix, some figures of merit, and the receiver operating characteristic curve have been used to evaluate and enhance the performance of the methods and choose the optimum decision threshold. A positive anomaly is usually found before the earthquakes, followed by an LST decrease after the event.Architectural optimization results for a network of earth-observing satellite nodes
http://hdl.handle.net/2117/386832
Architectural optimization results for a network of earth-observing satellite nodes
Araguz López, Carles; Llaveria Godoy, David; Lancheros Sepulveda, Estefany Maria; Bou Balust, Elisenda; Camps Carmona, Adriano José; Alarcón Cot, Eduardo José; Lluch i Cruz, Ignasi; Matevosyan, Hripsime; Golkar, Alessandro; Tonetti, Stefania; Cornara, Stefania; Cote, Judith; Pierotti, Stéphane; Rodríguez, Pedro; Alvaro Sanchez, A.; Sochacki, Mateusz; Narkiewicz, Janusz
Earth observation satellite programs are currently facing, for some applications, the need to deliver hourly revisit times, sub-kilometric spatial resolutions and near-real-time data access times. These stringent requirements, combined with the consolidation of small-satellite platforms and novel distributed architecture approaches, are stressing the need to study the design of new, heterogeneous and heavily networked satellite systems that can potentially replace or complement traditional space assets. In this context, this paper presents partial results from ONION, a research project devoted to study distributed satellite systems and their architecting characteristics. A design-oriented framework that allows selecting optimal architectures for a given user needs is presented in this paper. The framework has been used in the study of a strategic use-case and its results are hereby presented. From an initial design space of 5586 unique architectures, the framework has been able to pre-select 28 candidate designs by an exhaustive analysis of their performance and by quantifying their quality attributes. This very exploration of architectures and the characteristics of the solution space, are presented in this paper along with the selected solution and the results of a detailed performance analysis.
2023-05-02T08:59:31ZAraguz López, CarlesLlaveria Godoy, DavidLancheros Sepulveda, Estefany MariaBou Balust, ElisendaCamps Carmona, Adriano JoséAlarcón Cot, Eduardo JoséLluch i Cruz, IgnasiMatevosyan, HripsimeGolkar, AlessandroTonetti, StefaniaCornara, StefaniaCote, JudithPierotti, StéphaneRodríguez, PedroAlvaro Sanchez, A.Sochacki, MateuszNarkiewicz, JanuszEarth observation satellite programs are currently facing, for some applications, the need to deliver hourly revisit times, sub-kilometric spatial resolutions and near-real-time data access times. These stringent requirements, combined with the consolidation of small-satellite platforms and novel distributed architecture approaches, are stressing the need to study the design of new, heterogeneous and heavily networked satellite systems that can potentially replace or complement traditional space assets. In this context, this paper presents partial results from ONION, a research project devoted to study distributed satellite systems and their architecting characteristics. A design-oriented framework that allows selecting optimal architectures for a given user needs is presented in this paper. The framework has been used in the study of a strategic use-case and its results are hereby presented. From an initial design space of 5586 unique architectures, the framework has been able to pre-select 28 candidate designs by an exhaustive analysis of their performance and by quantifying their quality attributes. This very exploration of architectures and the characteristics of the solution space, are presented in this paper along with the selected solution and the results of a detailed performance analysis.FSSCat Mission description and first scientific results of the FMPL-2 onboard 3CAT-5/A
http://hdl.handle.net/2117/386798
FSSCat Mission description and first scientific results of the FMPL-2 onboard 3CAT-5/A
Camps Carmona, Adriano José; Muñoz Martin, Joan Francesc; Ruiz De Azúa Ortega, Juan Adrián; Fernandez Capon, Lara Pilar; Pérez Portero, Adrián; Llaveria Godoy, David; Herbert, Christoph Josef; Pablos Hernández, Miriam; Golkar, Alessandro; Gutiérrez Peña, Antonio
FSSCat, the “Federated Satellite Systems/ 3 Cat-5” mission was the winner of the 2017 ESA S^3 (Sentinel Small Satellite) Challenge and overall winner of the Copernicus Masters competition. FSSCat consists of two 6 unit cubesats carrying on board UPC's Flexible Microwave Payload - 2 (FMPL-2), an L-band microwave radiometer and GNSS-Reflectometer implemented in a software defined radio, and Cosine's HyperScout-2 visible and near infrared + thermal infrared hyperspectral imager, enhanced with PhiSat-1, a on board Artificial intelligence experiment for cloud detection. Both spacecrafts include optical and UHF inter-satellite links technology demonstrators, provided by Golbriak Space and UPC, respectively. This paper describes the mission, and the main scientific results of the FMPL-2 obtained during the first three months of the mission, notably the sea ice concentration and thickness, and the downscaled soil moisture products over the Northern hemisphere.
2023-04-28T08:12:43ZCamps Carmona, Adriano JoséMuñoz Martin, Joan FrancescRuiz De Azúa Ortega, Juan AdriánFernandez Capon, Lara PilarPérez Portero, AdriánLlaveria Godoy, DavidHerbert, Christoph JosefPablos Hernández, MiriamGolkar, AlessandroGutiérrez Peña, AntonioFSSCat, the “Federated Satellite Systems/ 3 Cat-5” mission was the winner of the 2017 ESA S^3 (Sentinel Small Satellite) Challenge and overall winner of the Copernicus Masters competition. FSSCat consists of two 6 unit cubesats carrying on board UPC's Flexible Microwave Payload - 2 (FMPL-2), an L-band microwave radiometer and GNSS-Reflectometer implemented in a software defined radio, and Cosine's HyperScout-2 visible and near infrared + thermal infrared hyperspectral imager, enhanced with PhiSat-1, a on board Artificial intelligence experiment for cloud detection. Both spacecrafts include optical and UHF inter-satellite links technology demonstrators, provided by Golbriak Space and UPC, respectively. This paper describes the mission, and the main scientific results of the FMPL-2 obtained during the first three months of the mission, notably the sea ice concentration and thickness, and the downscaled soil moisture products over the Northern hemisphere.On the potential of empirical mode decomposition for RFI mitigation in microwave radiometry
http://hdl.handle.net/2117/374526
On the potential of empirical mode decomposition for RFI mitigation in microwave radiometry
Díez García, Raúl; Camps Carmona, Adriano José; Hyuk, Park
Radio-frequency interference (RFI) is an increasing problem particularly for Earth observation using microwave radiometry. RFI has been observed, for example, at L-band by the European Space Agency’s (ESA’s) soil moisture and ocean salinity (SMOS) Earth Explorer and by National Aeronautics and Space Administration’s (NASA’s) soil moisture active passive (SMAP) and Aquarius missions, as well as at C-band by Advanced Microwave Scanning Radiometer (AMSR)-E and AMSR-2, and at 10.7 and 18.7 GHz by AMSR-E, AMSR-2, WindSat, and GPM Microwave Imager (GMI). Therefore, systems dedicated to interference detection and removal of contaminated measurements are nowadays a must in order to improve radiometric accuracy and reduce the loss of spatial coverage caused by interference. In this work, the feasibility of using the empirical mode decomposition (EMD) technique for RFI mitigation is explored. The EMD, also known as Hilbert–Huang transform (HHT), is an algorithm that decomposes the signal into intrinsic mode functions (IMFs). The achieved performance is analyzed, and the opportunities and caveats that this type of methods present are described. EMD is found to be a practical RFI mitigation method, albeit presenting some limitations and considerable complexity. Nevertheless, in some conditions, EMD exhibits a better performance than other commonly used methods (such as frequency binning). In particular, it has been found that EMD performs well for RFI affecting the <25% lower part of the intermediate frequency (IF) bandwidth.
2022-10-18T07:26:51ZDíez García, RaúlCamps Carmona, Adriano JoséHyuk, ParkRadio-frequency interference (RFI) is an increasing problem particularly for Earth observation using microwave radiometry. RFI has been observed, for example, at L-band by the European Space Agency’s (ESA’s) soil moisture and ocean salinity (SMOS) Earth Explorer and by National Aeronautics and Space Administration’s (NASA’s) soil moisture active passive (SMAP) and Aquarius missions, as well as at C-band by Advanced Microwave Scanning Radiometer (AMSR)-E and AMSR-2, and at 10.7 and 18.7 GHz by AMSR-E, AMSR-2, WindSat, and GPM Microwave Imager (GMI). Therefore, systems dedicated to interference detection and removal of contaminated measurements are nowadays a must in order to improve radiometric accuracy and reduce the loss of spatial coverage caused by interference. In this work, the feasibility of using the empirical mode decomposition (EMD) technique for RFI mitigation is explored. The EMD, also known as Hilbert–Huang transform (HHT), is an algorithm that decomposes the signal into intrinsic mode functions (IMFs). The achieved performance is analyzed, and the opportunities and caveats that this type of methods present are described. EMD is found to be a practical RFI mitigation method, albeit presenting some limitations and considerable complexity. Nevertheless, in some conditions, EMD exhibits a better performance than other commonly used methods (such as frequency binning). In particular, it has been found that EMD performs well for RFI affecting the <25% lower part of the intermediate frequency (IF) bandwidth.Parametric analysis of an L-band deployable offset reflector for CubeSats
http://hdl.handle.net/2117/374430
Parametric analysis of an L-band deployable offset reflector for CubeSats
Mendez Soto, Mario Alberto; Marquez-Alperi, Adrián; Fernández Niño, Elena; Camps Carmona, Adriano José
Thanks to the advances in the miniaturization and improved power consumption efficiency of electronics, computers, cell phone technologies, etc., today’s spacecrafts and payloads are reducing their size and increasing their performance. However, not all systems can be reduced, as their dimensions are determined by the laws of physics. This study is focused on the design of an L-band reflector antenna for a CubeSat-based Earth observation mission devoted to measure the surface soil moisture. Two configurations of deployable parabolic reflector antennas and meshes are presented from the mechanical point of view. The electromagnetic analyses including the antenna feeder are also presented. It is found that the regular circular mesh performs slightly better than the irregular one, although requires a more careful manufacturing process.
2022-10-14T07:29:59ZMendez Soto, Mario AlbertoMarquez-Alperi, AdriánFernández Niño, ElenaCamps Carmona, Adriano JoséThanks to the advances in the miniaturization and improved power consumption efficiency of electronics, computers, cell phone technologies, etc., today’s spacecrafts and payloads are reducing their size and increasing their performance. However, not all systems can be reduced, as their dimensions are determined by the laws of physics. This study is focused on the design of an L-band reflector antenna for a CubeSat-based Earth observation mission devoted to measure the surface soil moisture. Two configurations of deployable parabolic reflector antennas and meshes are presented from the mechanical point of view. The electromagnetic analyses including the antenna feeder are also presented. It is found that the regular circular mesh performs slightly better than the irregular one, although requires a more careful manufacturing process.Numerical solver for vertical air motion estimation
http://hdl.handle.net/2117/374181
Numerical solver for vertical air motion estimation
Salcedo Bosch, Andreu; Domínguez Pla, Paula; Rocadenbosch Burillo, Francisco; Frasier, Stephen J.
We present preliminary research on a method to estimate Vertical Air Motion (VAM) at a particular height by comparing the measured rain-rate (RR) by a vertically-pointing S-band Frequency-Modulated Continuous-Wave (FMCW) radar with that of a ground-based disdrometer. The method is based on a constrained parametric solver, assuming high correlation between 5-min averaged rain rates measured by the radar and disdrometer. The method is tested over disdrometer and radar observations during the Verification of the ORigins Tornado EXperiment in South East US (VORTEX-SE) project. Finally, the results are partially validated by means of fitting a gamma distribution to the VAM-corrected DSD profiles and studying its parameters.
2022-10-07T11:53:15ZSalcedo Bosch, AndreuDomínguez Pla, PaulaRocadenbosch Burillo, FranciscoFrasier, Stephen J.We present preliminary research on a method to estimate Vertical Air Motion (VAM) at a particular height by comparing the measured rain-rate (RR) by a vertically-pointing S-band Frequency-Modulated Continuous-Wave (FMCW) radar with that of a ground-based disdrometer. The method is based on a constrained parametric solver, assuming high correlation between 5-min averaged rain rates measured by the radar and disdrometer. The method is tested over disdrometer and radar observations during the Verification of the ORigins Tornado EXperiment in South East US (VORTEX-SE) project. Finally, the results are partially validated by means of fitting a gamma distribution to the VAM-corrected DSD profiles and studying its parameters.On adaptive unscented Kalman filtering for floating Doppler wind-lidar motion correction: Effect of the number of lidar measurement heights
http://hdl.handle.net/2117/374178
On adaptive unscented Kalman filtering for floating Doppler wind-lidar motion correction: Effect of the number of lidar measurement heights
Salcedo Bosch, Andreu; Rocadenbosch Burillo, Francisco; Sospedra Iglesias, Joaquim
This work studies the influence of the number of lidar measurement heights on the performance of the floating Doppler wind lidar motion-correction algorithm, recently published by the authors. The work is in the context of offshore wind energy and continuous-wave focusable ZephirTM 300 lidar. A downsampling technique applied over the lidar-measured wind speed time-series is used to simulate different height-sounding configurations. The operation of the filter under one, three, and five measurement heights of the lidar is studied by using data from El Pont del Petroli measurement campaign. The filter is proved to remove apparent turbulence addition in all three cases, showing a deterioration of statistical indicators as the number of sounding heights increase.
2022-10-07T11:40:39ZSalcedo Bosch, AndreuRocadenbosch Burillo, FranciscoSospedra Iglesias, JoaquimThis work studies the influence of the number of lidar measurement heights on the performance of the floating Doppler wind lidar motion-correction algorithm, recently published by the authors. The work is in the context of offshore wind energy and continuous-wave focusable ZephirTM 300 lidar. A downsampling technique applied over the lidar-measured wind speed time-series is used to simulate different height-sounding configurations. The operation of the filter under one, three, and five measurement heights of the lidar is studied by using data from El Pont del Petroli measurement campaign. The filter is proved to remove apparent turbulence addition in all three cases, showing a deterioration of statistical indicators as the number of sounding heights increase.Floating lidar assessment of atmospheric stability in the North Sea
http://hdl.handle.net/2117/374172
Floating lidar assessment of atmospheric stability in the North Sea
Silva, Marcos Paulo Aráujo da; Rocadenbosch Burillo, Francisco; Farré Guarné, Joan; Salcedo Bosch, Andreu; González Marco, Daniel; Peña Diaz, Alfredo
In this work, the 2D parametric-solver algorithm [1] used to assess atmospheric stability from floating Doppler wind lidar (FDWL) measurements is revisited. The algorithm performance is studied using data from IJmuiden campaign. Mast-measured temperature and wind-speed provided the reference parameters used to evaluate the performance of the stability estimation algorithm. From 5,922 10-min samples available, the algorithm classified the atmosphere as stable (52% of the cases), neutral (31%) and unstable (17%), which successfully agreed with the mast-derived reference classification (53%, 30% and 17%, respectively).
2022-10-07T11:28:17ZSilva, Marcos Paulo Aráujo daRocadenbosch Burillo, FranciscoFarré Guarné, JoanSalcedo Bosch, AndreuGonzález Marco, DanielPeña Diaz, AlfredoIn this work, the 2D parametric-solver algorithm [1] used to assess atmospheric stability from floating Doppler wind lidar (FDWL) measurements is revisited. The algorithm performance is studied using data from IJmuiden campaign. Mast-measured temperature and wind-speed provided the reference parameters used to evaluate the performance of the stability estimation algorithm. From 5,922 10-min samples available, the algorithm classified the atmosphere as stable (52% of the cases), neutral (31%) and unstable (17%), which successfully agreed with the mast-derived reference classification (53%, 30% and 17%, respectively).Synergistic mixed-layer height retrieval method using microwave radiometer and lidar ceilometer observations
http://hdl.handle.net/2117/374166
Synergistic mixed-layer height retrieval method using microwave radiometer and lidar ceilometer observations
Silva, Marcos Paulo Aráujo da; Rocadenbosch Burillo, Francisco; Tanamachi, Robin; Saeed, Umar
This paper tackles synergistic mixed-layer height (MLH) estimation via a combination of microwave radiometer (MWR) and lidar ceilometer (LC)-based estimates. While MLH-MWR estimates rely on potential temperature retrievals, MLH-LC estimates rely on aerosol gradients. The pros and cons of MLH retrievals obtained from MWR via the parcel method and from LC via an extended Kalman filter (EKF)-based method are used to motivate the synergistic algorithm. The synergistic algorithm is introduced as a maximum-likelihood combination of MLH-MWR and MLH-LC. Two case examples from the 2013 HOPE campaign at Jülich, Germany, are used to show the robustness of the synergistic method and the effect of surface temperature measurement error. Doppler wind lidar retrievals and radiosonde reference MLH estimates are used for validation.
2022-10-07T11:06:36ZSilva, Marcos Paulo Aráujo daRocadenbosch Burillo, FranciscoTanamachi, RobinSaeed, UmarThis paper tackles synergistic mixed-layer height (MLH) estimation via a combination of microwave radiometer (MWR) and lidar ceilometer (LC)-based estimates. While MLH-MWR estimates rely on potential temperature retrievals, MLH-LC estimates rely on aerosol gradients. The pros and cons of MLH retrievals obtained from MWR via the parcel method and from LC via an extended Kalman filter (EKF)-based method are used to motivate the synergistic algorithm. The synergistic algorithm is introduced as a maximum-likelihood combination of MLH-MWR and MLH-LC. Two case examples from the 2013 HOPE campaign at Jülich, Germany, are used to show the robustness of the synergistic method and the effect of surface temperature measurement error. Doppler wind lidar retrievals and radiosonde reference MLH estimates are used for validation.