A5038937968- Advanced SAR Imaging Techniques
- Synthetic Aperture Radar (SAR) Applications and Techniques
- Radar Systems and Signal Processing
- Microwave Imaging and Scattering Analysis
- Underwater Acoustics Research
- Arctic and Antarctic ice dynamics
- Soil Moisture and Remote Sensing
- Ocean Waves and Remote Sensing
- Geophysical Methods and Applications
- Oceanographic and Atmospheric Processes
- Advanced Optical Sensing Technologies
- Sparse and Compressive Sensing Techniques
- Methane Hydrates and Related Phenomena
- Structural Health Monitoring Techniques
- Ultrasonics and Acoustic Wave Propagation
- Advanced Computational Techniques and Applications
- Image and Signal Denoising Methods
- Non-Invasive Vital Sign Monitoring
- Blind Source Separation Techniques
- Cryospheric studies and observations
- Remote-Sensing Image Classification
- Geophysics and Gravity Measurements
- Antenna Design and Optimization
- Sensor Technology and Measurement Systems
- Speech and Audio Processing
University of Bucharest
2023-2025
Universitatea Națională de Știință și Tehnologie Politehnica București
2015-2024
Deutsches Zentrum für Luft- und Raumfahrt e. V. (DLR)
2022
Victor Babeș University of Medicine and Pharmacy Timișoara
2022
SpaceTech (United States)
2022
Infineon Technologies (Austria)
2019-2020
Grenoble Images Parole Signal Automatique
2011-2016
Romanian Space Agency
2015
Centre National de la Recherche Scientifique
2014
Institut polytechnique de Grenoble
2014
The recognition or understanding of the scenes observed with a synthetic aperture radar (SAR) system requires broader range cues beyond spatial context. These encompass but are not limited to imaging geometry, mode, properties Fourier spectrum images, behavior polarimetric signatures. In this article, we propose change paradigm for explainability in data science case SAR ground explainable artificial intelligence (XAI) SAR. It aims use transformations based on well-established models...
The frequency-modulated continuous-wave (FMCW) radar is an alternative to the pulse when distance target short. Typical FMCW implementations have a homodyne architecture transceiver which limits performances for short-range applications: beat frequency can be relatively small and placed in range affected by specific issues (dc offset, self-mixing, 1/f noise). In addition, one classical problem of that voltage-controlled oscillator adds certain degree nonlinearity cause dramatic resolution...
Deep learning models have achieved remarkable success in many different fields and attracted interests. Several researchers attempted to apply deep Synthetic Aperture Radar (SAR) data processing, but it did not the same breakthrough as other fields, including optical remote sensing. SAR are complex domain by nature processing them with Real-Valued (RV) networks neglects phase component which conveys important distinctive information. A Complex-Valued (CV) end-to-end network is developed this...
The interest of the automotive industry has progressively focused on subjects related to driver assistance systems as well autonomous cars. Cars combine a variety sensors perceive their surroundings robustly. Among them, radar are indispensable because independence lighting conditions and possibility directly measure velocity. However, interference is an issue that becomes prevalent with increasing amount in scenarios. In this paper, we address for frequency modulated continuous wave (FMCW)...
Spaceborne synthetic aperture radar (SAR) can provide accurate images of the ocean surface roughness day-or-night in nearly all weather conditions, being an unique asset for many geophysical applications. Considering huge amount data daily acquired by satellites, automated techniques physical features extraction are needed. Even if supervised deep learning methods attain state-of-the-art results, they require a great labelled data, which difficult and excessively expensive to acquire SAR...
Monitoring large built structures, landslides, volcanoes, or glaciers implies relative height measurements and line-of-sight (LOS) displacement measurements, which are typically performed with monostatic spaceborne synthetic aperture radar (SAR) sensors. In this case, for each satellite that illuminates a given location, we can usually exploit only the information available from one ascending/descending orbit, if uses multiple subswaths, is obtained subswath per orbit. A bistatic...
Despite the state-of-the-art performance of deep learning methods for Synthetic Aperture Radar (SAR) data classification, Real-Valued (RV) networks neglect phase component Complex-Valued (CV) SAR and lose a lot useful information. CV architectures have been developed in recent years to exploit amplitude components data, different fields. However, superiority models over RV are proved be each application, more investigation into advantages disadvantages implementing classification is...
Radar sensors are gradually becoming a wide-spread equipment for road vehicles, playing crucial role in autonomous driving and safety. The broad adoption of radar increases the chance interference among from different generating corrupted range profiles range-Doppler maps. In order to extract distance velocity multiple targets maps, affecting each profile needs be mitigated. this paper, we propose fully convolutional neural network automotive mitigation. train our real-world scenario,...
Coastline extraction by exploiting optical images is challenging during adverse weather conditions. This letter proposes coastline from synthetic aperture radar (SAR) data. Since collecting <italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">in-situ</i> data expensive and not always possible, the Doppler parameter used to delineate coastlines when neither nor cloud-free are available. We propose a novel method based on classic coastal dynamic...
Recent studies revealed that the time-domain synthetic aperture radar (SAR) processors are more appropriate for future innovative SAR missions (e.g., ROSE-L, Harmony) not only due to their ability form image on user-defined regions of interest (ROIs) but also straightforward accommodation configurations wherein azimuth spectrum folding occurs TOPSAR). In this letter, we propose an accelerated Back-Projection (BP) processor working in conjunction with a fast routine generating elliptical grid...
Recently, structural monitoring by radar remote sensing has become more necessary for both economic and security reasons. Infrastructure with no incorporated deformation sensors (e.g., old generation water dams which regulations did not impose capabilities) is usually performed regular in situ topographic surveys. However, these surveys cannot be very often, alternative methods are desirable. A feasible nonintrusive way to monitor such a structure interferometric synthetic aperture (SAR)...
This paper presents the first SAR imaging results obtained with a fixed ground-based system used in bistatic configuration having TerraSAR-X satellite as transmitter of opportunity. The system's characteristics and signal processing flow are presented relative to state art. Compared previous works on where significant amount is dedicated time/frequency synchronization between ground receiver, we show that image only meter-range geographic offset can be using vectors from monostatic minimal...
In this paper, we propose a bistatic synthetic aperture radar (SAR) imaging procedure using Sentinel-1 satellite as transmitter of opportunity and stationary ground receiver. The is designed for the standard operating mode satellites - Terrain Observation with Progressive Scans SAR (TOPSAR) essentially comprises synchronization between receiver focusing algorithm. proposed method takes into account particularities imposed by antenna beam sweep from back to forth (specific TOPSAR mode)...
The article proposes a methodology to perform azimuth focusing of spaceborne transmitter-stationary receiver bistatic synthetic aperture radar data across multiple along-track apertures increase resolution. procedure uses as input several (continuous groups range compressed pulses) from one or more satellite bursts and comprises the following stages: antenna pattern compensation, slow time resampling, reconstruction missing samples between neighboring sets pulses using an autoregressive (AR)...
A frequency modulated continuous wave (FMCW) X-band radar platform for millimetric displacements measurement of short-range targets is presented in this paper. The platform's transceiver based on a heterodyne architecture because the beat relatively small and it can be placed range influenced by specific homodyne problems: DC offset, self-mixing 1/f noise. displacement capability was tested profiles SAR images acquired various targets. were computed from interferometric phase. errors...
Infrastructure monitoring applications can require the tracking of slowly moving points a certain structure. Given point from structure to be monitored, in context available spaceborne synthetic aperture radar (SAR) products, where image is already focused slant range-azimuth grid, it not obvious if this scattering center, layover or visible respective orbit. This paper proposes centers detection and procedure based on refocusing set SAR images provided high-resolution grid The designed for...
An improved composite right/left-handed (CRLH) unit cell optimized for a leaky-wave (LW) antenna is presented. This CRLH consists of series one transmission line, an interdigital capacitor, another line and shunt shorted stub. Introducing the lines, parasitic self-resonances capacitor are shifted outside operational band, radiation range extended transition frequency at which balanced condition achieved can be chosen in design process from broader frequencies. The characteristics...
Among the actual trends that will affect society in coming years, autonomous driving stands out as having potential to disruptively change automotive industry we know it today. For this, fail-operational behavior is essential sense, plan, and act stages of automation chain order handle safety-critical situations by its own, which currently not reached with state-of-the-art approaches also due missing reliable environment perception sensor fusion. PRYSTINE realize Fail-operational Urban...
In this paper, we propose a novel ultrasonic tomography method for pipeline flow field imaging, based on the Zernike polynomial series. Having intrusive multipath time-offlight measurements (difference in flight time and speed of ultrasound) at input, provide output tomograms fluid velocity components (axial, radial, orthoradial velocity). Principally, by representing these velocities as series, reduce problem to an ill-posed finding coefficients relying acquired measurements. Thereupon, is...
This letter proposes a micro-Doppler (m-D) reconstruction method for spaceborne synthetic aperture radar (SAR) images using azimuth time-frequency tracking of the phase history. The algorithm involves an defocusing SAR image in order to gain access history, followed by algorithm. is based on local polynomial modeling as estimator coefficients high-order ambiguity function. approach presented context vibration estimation infrastructure monitoring applications, with emphasis parameters from...
The multiplicative model, expressed as a product between the square root of scalar positive quantity (texture) and description an equivalent homogeneous surface (speckle), is one most appropriate disseminated models used to describe high-resolution polarimetric synthetic aperture radar (PolSAR) clutter. Generally, texture assumed polarization independent, which causes PolSAR data present spherical symmetry property, allowing for usage algorithms in literature. Nevertheless, existence...