Matteo Pardini

• PhD
• Researcher at German Aerospace Center (DLR)

This study investigates ice features of unknown glaciological origin in the ablation zone of southwest Greenland, focusing on the land-terminating Russell Glacier. Using data from an experimental airborne SAR (Synthetic Aperture Radar) campaign of the German Aerospace Center (DLR), the research employs a range of advanced techniques, including SAR...

The main goal of the TerraSAR-X Add-On for Digital Elevation Measurements (TanDEM-X) mission is the generation of a global digital elevation model (DEM) of unprecedented accuracy and coverage. The global TanDEM-X DEM product became available in 2016, surpassed all expectations, and became a reference for a wide range of Earth science, commercial, a...

A R T I C L E I N F O Editor: Jing M. Chen Keywords: Forest height Fusion Lidar GEDI InSAR TanDEM-X Model-based inference A B S T R A C T NASA's Global Ecosystem Dynamic Investigation (GEDI) mission provides billions of lidar samples of canopy structure over the Earth's temperate and pantropical forests. Using the GEDI sample data alone, gridded he...

Tomographic Synthetic Aperture Radar (SAR) allows the reconstruction of the 3D radar reflectivity of forests from a large(r) number of multi-angular acquisitions. However, in most practical implementations it suffers from limited vertical resolution and/or reconstruction artefacts as the result of non-ideal acquisition setups. Polarisation Coherenc...

Model-based forest height inversion from single-and multi-baseline Pol-InSAR data is today well-established. One of the critical performance points is the parameterisation of the vertical reflectivity profile. In this paper, the parameterisation of the vertical reflectivity profile using a tomographic reconstruction is proposed. To mitigate the lim...

Our ability to infer the impact of land use changes such as deforestation and reforestation on concentrations of atmospheric CO 2 rests upon accurate and spatially resolved estimates of forest structure, namely canopy height, aboveground biomass (AGB) and biomass density (AGBD). Since April 2019, NASA’s Global Ecosystem Dynamic Investigation (GEDI)...

The present study addresses the development, implementation and validation of a forest height mapping scheme based on the combination of TanDEM-X interferometric coherence and GEDI waveform measurements. The very general case where only a single polarisation TanDEM-X interferogram, a set of spatially discrete GEDI waveform measurements and no DTM a...

This paper addresses the implementation of an above ground biomass (AGB) estimation scheme relying on the height-to-biomass allometry at stand level in the context of the synergistic use of continuous TanDEM-X (bistatic) interferometric synthetic aperture radar acquisitions and spatial discrete GEDI waveform lidar measurements. The estimation of fo...

The changes in time of 3D reflectivity reconstructions obtained by means of synthetic aperture radar tomography (TomoSAR) in forest scenes are caused by changes of the physical forest structure, tree water content and surface moisture. In this paper, a framework to separate and characterize different change components is introduced by for-mulating...

Polarimetric SAR Interferometry (Pol-InSAR) is a SAR remote sensing discipline with unique and powerful applications related to the vertical structure of natural and man-made volume scatterers. The coherent combination of single- or multi -baseline interferograms acquired at different polarisations provides sensitivity to the vertical distribution...

ESA Forest Carbon Monitoring project (FCM) is developing Earth Observation based, user-centric approaches for forest carbon monitoring. Forest carbon accounting based on forest inventory requires precise and timely estimation of forest variables at various spatial levels accompanied by verifiable uncertainty information. In this paper, we present t...

The combination of TanDEM-X interferometric measurements with GEDI lidar full waveform measurements can provide continuous high-resolution forest height maps at global scale with sufficient accuracy without using external information about the underlyingtopography. In previous studies, the GEDI lidar full waveforms have been used to provide an appr...

"ROSE-L Tandem" is a concept to extend ESA's two monostatic ROSE-L satellites by a third satellite. This third satellite will fly in close formation with one of the two monostatic ones to create a bi-static, single-pass SAR interferometer. Main applications are tomography of forests and ice and the generation of Digital Elevation Models. A joint DL...

Allometric relations that link forest above ground biomass to top forest (i.e. canopy) height are of particular significance in the context of lidar and interferometric Synthetic Aperture Radar (SAR) remote sensing, as both techniques allow accurate height measurements at ecologically relevant spatial scales. Besides the often unknown allometry its...

Synthetic Aperture Radar (SAR) measurements are unique for mapping forest 3D structure and its changes in time. Tomographic SAR (TomoSAR) configurations exploit this potential by reconstructing the 3D radar reflectivity. The frequency of the SAR measurements is one of the main parameters determining the information content of the reconstructed refl...

Model-based forest height inversion from Pol-InSAR data relies on the realistic parameterization of the underlying (vertical) radar reflectivity function. In the context of interferometric TanDEM-X measurements - especially in the global single pol DEM mode - this is not possible due to the limited dimensionality of the observation space. In order...

Synthetic Aperture Radar (SAR) waves at low frequency can penetrate through the different forest layers down to the ground. The received signal contains information not only on the 3-D distribution of the vegetation scatterers, but also on the underlying ground. Using multiple acquisitions, SAR tomographic (TomoSAR) techniques estimate vertical re-...

Polarization Coherence Tomography addresses the TomoSAR inversion by approximating the vertical reflectivity profile by a weighting functions of a basis. The individual weights can be estimated from the available interferometric coherences. This concept becomes particularly suitable for space borne TomoSAR implementations over forest volumes in whi...

With decreasing frequency synthetic aperture radar (SAR) pulses penetrate more and more into and through vegetation layers, and interact with vegetation elements located at different heights within the forest volume and with the underlying ground. This, combined with the ability of SAR tomographic (TomoSAR) techniques to reconstruct the 3D radar re...

The estimation and monitoring of 3D forest structure at large scales strongly relies on the use of remote sensing techniques. Today, two of them are capable to provide 3D forest structure estimates: lidar and Synthetic Aperture Radar (SAR) configurations. The differences in wavelength, imaging geometry, and technical implementation make the measure...

Synthetic aperture radar tomography (TomoSAR) at lower frequencies allows the reconstruction of the 3-D radar reflectivity of volume scatterers allowing access to their physical 3-D structure by means of multiangular SAR acquisitions. The performance of the reconstruction critically depends on the number and (spatial) distribution of the tomographi...

TanDEM-X experiments have shown that forest height can be estimated with single polarization X-band interferometric coherences. An external digital terrain model (DTM) not only allows to use both coherence magnitude and phase information, but also to overcome X-band penetration limitations. However, DTM information is not available for large areas....

The application of polarimetric Synthetic Aperture Radar (SAR) to forest observation for mapping, classification and parameter estimation (especially biomass) has a relatively long history. The radar penetration through forest volume, and hence the multi-layer nature of scattering models, make fully polarimetric data the observation space enabling...

Recent TanDEM-X experiments have shown that forest height can be estimated with the single polarization X-band interferometric coherences. However, an external digital terrain model (DTM) is necessary to retrieve canopy height. Forest height derived from coherence model inversion is known as to be only accurate in certain condition like boreal fore...

The full waveform GEDI lidar mission will map forest height and biomass at 1 km resolution globally in temperate and tropical forests. In order to obtain biomass maps with higher resolution and overcome the limitations of the footprint sampling on ground, the possibility to combine GEDI waveforms and TanDEM-X coherences is currently considered usin...

Knowledge of the spatial patterns of successional stages (i.e., primary and secondary forest) in tropical forests allows to monitor forest preservation, mortality and regeneration in relation to natural and anthropogenic disturbances. Different successional stages have also different capabilities of re-establishing carbon stocks. Therefore, a succe...

Forest structure is a key parameter for forest applications, but it is difficult to be estimated at the required spatial and temporal scales. In this context, synthetic aperture radar Tomography (TomoSAR) that allows, at lower frequencies, the 3-D imaging of natural volume scatterers with high spatial and temporal resolution may be a game changer....

The need of large scale observations with high temporal frequency has promoted airborne and satellite remote sensing techniques for glaciological applications. In particular, active microwave sensors, such as synthetic aperture radars (SARs), offer all-weather and daylight independent operability which is of great advantage at high latitudes, where...

NASA’s Global Ecosystem Dynamics Investigation (GEDI) waveform lidar is expected to provide unprecedented measurements of forest structure and biomass in tropical and temperate environments. In order to bridge the limitations induced by the ground sampling of the GEDI waveforms, and to obtain enhanced forest structure estimates, the potential of co...

The objective of this paper is to address the penetration capabilities of different synthetic aperture radar (SAR) frequencies in forest scenarios in terms of “visibility” of the ground. First, the ratio between the ground and the volume scattering powers is estimated from multi-baseline polarimetric interferometric (Pol-InSAR) data across differen...

The estimation and monitoring of 3D forest structure at large scales strongly rely on the use of remote sensing techniques. Today, two of them are able to provide 3D forest structure estimates: lidar and synthetic aperture radar (SAR) configurations. The differences in wavelength, imaging geometry, and technical implementation make the measurements...

The wavelength of synthetic aperture radar (SAR) waves affects the sensitivity to scatterers depending on their size and the penetration through forest volumes. Therefore, forest backscattering at different wavelengths (from P- up to X-band) contains different structural information about the geometry of vegetation elements and their distribution i...

There is a common agreement on the relevance of L-band wavelengths (around 20 cm) for forest observation. For instance, the larger backscatter dynamic range increases the sensitivity to larger biomass gradients with respect to C- and X-band. Furthermore, L-band allows the penetration into and through dense forest canopies in all forest ecosystems,...

Synthetic aperture radar (SAR) remote sensing configurations are able to provide continuous measurements on global scales sensitive to the vertical structure of forests with a high spatial and temporal resolution. Furthermore, the development of tomographic SAR techniques allows the reconstruction of the three-dimensional (3-D) radar reflectivity o...

Synthetic Aperture Radar (SAR) Tomography (TomoSAR) allows reconstructing a vertical profile of the power backscattered by natural volumes by combining more than two SAR images acquired with slightly different incidence angles. Being an electromagnetic quantity, the profile depends on the radar frequency, polarization, and acquisition geometry, but...

The aim of this paper is to compare L- and P-band vertical backscattering profiles estimated by means of Synthetic Aperture Radar (SAR) Tomography (TomoSAR) and full LIght Detection And Ranging (lidar) waveforms in terms of their ability to distinguish different tropical forest structure types. The comparison relies on the unique DLR F-SAR and NASA...

Polarimetric SAR Interferometry (Pol-InSAR) is a SAR remote sensing discipline with unique and powerful applications related to the vertical structure of natural and man-made volume scatterers. The coherent combination of single- or multi-baseline interferograms acquired at different polarisations provides sensitivity to the vertical distribution o...

Synthetic Aperture Radar Tomography techniques provide 3D information of the forest due to the ability of microwaves to penetrate through vegetation. Recent studies link the radar 3D information to forest 3D structure in order to translate the tomographic results to an ecological interpretation. However, due to the undersampled nature of tomographi...

Recent TanDEM-X experiments have shown that the limited penetration capability at X-band in forest volumes allow the estimation of the height variability of the top canopy layer, which can be used as a proxy to the horizontal structure (i.e. heterogeneity), by using high resolution digital elevation models (DEMs). However, the use of an external di...

Understanding the impact of soil and plant parameter changes in agriculture on Synthetic Aperture Radar (SAR) measurements is of great interest when it comes to monitor the temporal evolution of agricultural crops by means of SAR. In this regard, specific transitions between phenological stages in corn, barley, and wheat have been identified associ...

The future SAR missions such as BIOMASS and Tandem-L will exploit the potential of Synthetic Aperture Radar Tomography to extract 3D forest structure information. Several algorithms can be applied for TomoSAR imaging. This paper analyses the performance of two non-parametric algorithms, Capon Beamforming and Compressive Sensing (CS), for forest str...

All radar frequencies (from P- up to X-band) can image horizontal and/or vertical forest structure, although with different structure information content and sensitivity. The assessment of both is crucial for instance in understanding synergies and complementarities of multiple SAR bands towards enhanced forest structure products. In this work, the...

Recently a framework for forest structure based on TomoSAR data has been defined. Based on the spatial distribution of the reflectivity peaks, two complementary descriptors are evaluated at a given scale. This paper high- lights the dependence of the structure estimate on scale and shows, through analysis on real and simulated data that the restric...

The aim of this paper is to interpret and characterize the changes of the 3-D polarimetric scattering signatures of agricultural crops at C-band and to relate them to temporal changes of the soil and plant parameters. For this, a time series of multibaseline (MB) synthetic aperture radar (SAR) data acquired at C-band by the airborne F-SAR system of...

Remote sensing systems have been demonstrated to be a powerful source of information for monitoring tropical forest ecosystems. In particular, Synthetic Aperture Radar (SAR) and LIght Detection And Ranging (lidar) systems provide measurements sensitive to 3-D forest structure parameters at high spatial and temporal resolutions. This is of critical...

Space borne implementations of SAR Tomography (TomoSAR) for forest volumes are particularly challenging even in a single-pass case, as the estimation of 3D reflectivity has to be carried out relying on a small number of acquisitions (or interferometric coherences) and/or non-uniform baseline distributions. A way to overcome this shortcoming is to a...

The penetration capability of microwaves into and through vegetation layers allows scattering interactions across the whole vertical vegetation extend. This, combined with the ability of multi-baseline Synthetic Aperture Radar (SAR) techniques to reconstruct the 3D radar reflectivity opens the door to the use of air- and space-borne SAR configurati...

A two-layer model composed by ground and volume contributions has been proven suitable to describe the 3-D backscattering signatures of forest scenarios in a number of experiments. Under this hypothesis, the purpose of this letter is to investigate how synthetic aperture radar tomography (TomoSAR) can be used to estimate ground and volume polarimet...

In forest and agricultural scattering scenarios, the backscattered synthetic aperture radar (SAR) signature consists, depending on the frequency, of the superposition of ground and volume scattering contributions. Using multibaseline SAR data, SAR tomography techniques allow resolving contributions occurring at different heights. Two algorithms for...

AfriSAR is an ESA-funded airborne P-band SAR campaign over the African tropical forests of Gabon that has been carried out by ONERA (July 2015) and DLR (February 2016) in support of the development of the geophysical algorithms of the future BIOMASS mission. In addition, DLR has complemented the P-band data set with an L-band one over the same site...

TanDEM-X forms together with TerraSAR-X the first single-pass polarimetric interferometer in space. This allows for the first time the acquisition and analysis of Single-, Dual-, and Quad-Pol-InSAR data without the disturbing effect of temporal decorrelation globally. For this reason, the exploration of TanDEM-X data for forestry is constantly incr...

The F-SAR instrument represents DLR’s advanced airborne SAR testbed for technology and remote sensing applications. The development of the instrument was triggered by a strong demand for data being simultaneously acquired at different wavelengths and polarizations as well as by the demand for very high range resolution. F-SAR is a modular developme...

Synthetic aperture radar Tomography (TomoSAR) is a powerful tool to investigate the relationship between 3-D radar backscattering and physical properties of agricultural vegetation. Here, TomoSAR algorithms are used to separate the ground and volume backscattered signals, and to investigate their properties. The estimated TomoSAR parameters are the...

Tandem-L is a highly innovative SAR satellite mission for the global observation of dynamic processes on the Earth's surface with hitherto unknown quality and resolution. Thanks to its novel imaging techniques and its unprecedented acquisition capacity, Tandem-L will deliver urgently needed information for the solution of pressing scientific questi...

In this paper we review the actual status of Pol-InSAR techniques and applications in forestry, agriculture and cryosphere; assess results from actual space (TanDEM-X) and air-borne (F-SAR) campaigns and experiments at different frequencies; and finally discuss new potential applications and challenges.

TanDEM-X forms together with TerraSAR-X the first single-pass polarimetric interferometer in space. This allows for the first time the acquisition and analysis of Single-, Dual-, and Quad-Pol-InSAR data without the disturbing effect of temporal decorrelation globally. Exploring the potential of (polarimetric) interferometric techniques to estimate...

The application of SAR Tomography (TomoSAR) to ice bodies is in a rather early stage, essentially due to the limited amount of experimental and validation data. In order to contribute to fill this gap, the objective of this paper is to present first results in the characterization of the 3-D backscattered signal of ice volumes at different frequenc...

Synthetic Aperture Radar Tomography (TomoSAR) allows the reconstruction of the 3D (radar) reflectivity opening the door for the estimation of 3D forest structure parameters. Future SAR missions will be able to provide global tomographic coverage in relative small revisit times, enabling the monitoring of 3D forest structure dynamics. In this poster...

TanDEM-X forms together with TerraSAR-X the first single-pass polarimetric interferometer in space. This al-lows for the first time the acquisition and analysis of Single-, Dual-, and Quad-Pol-InSAR data without the disturbing effect of temporal decorrelation globally. Exploring the potential of (polarimetric) interferometric tech-niques to estimat...

Synthetic aperture radar (SAR) tomography is a powerful approach to investigate, widely model free, the relationship between 3-D radar backscattering and physical structure of agricultural vegetation which is not fully understood yet. In this paper, the focus is set on the polarimetric characterization of scattering differences and the detection of...