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The basic idea of direct geo-referencing (DG) was realized and refined in this paper by introducing 19 additional parameters for self-calibration of airborne pushbroom hyperspectral images with in-flight GPS/IMU data. It is demonstrated that the proposed self-calibrated DG approach significantly rectify the geometric distortions caused by misalignments in GPS/IMU, aircraft vibration, interior parameters...
In this work we report the main conclusions of the European Space Agency (ESA) Metawave project (Mitigation of Electromagnetic Transmission errors induced by Atmospheric Water Vapour Effects) for what concerns the Synthetic Aperture Radar Interferometry (InSAR) viewpoint. The Atmospheric Phase Screen (APS) estimated with the Permanent Scatterers (PS) technique in the test sites of Roma and Como has...
We analyze the temporal evolution of the deformation affecting the Yellowstone (Wyoming, U.S) complex volcanic system in the 1992–2010 time period. This work represents, at our knowledge, the first attempt at retrieving through differential synthetic aperture radar (DInSAR) techniques long-term deformation time-series at the Yellowstone Caldera. This is due to the presence of severe temporal decorrelation...
Bi-static remote sensing with GPS signal (direct and reflect signals) has supported some researches in soil moisture measuring, sea state estimating and sea altimetry monitoring. In these researches the special designed receivers are generally required, such as the “delay-mapping” GPS receiver or open loop differential real-time receiver, because they can find the characteristics of the reflected...
GPR is a geophysical method which uses electromagnetic pulse radiation to make the image of subsurface and objects in it. The main advantage of the method is that it is nondestructive method. In this paper we proposed to use transformation of coordinates from iGPS system to GPS format for synchronization measurement traces and it coordinates in the RAMAC system. The experimental data was processed...
The topic of registering multi- and hyperspectral imagery is well studied in literature. However when the registration must be done between multispectral images and vector data, the literature is more limited. In this paper we focus on registering aerial images in the thermal (IR) band, and vector data delineating houses and other man-made structures in the same region. This differs from classical...
In this paper, we proposed the circularly polarized Synthetic aperture radar onboard microsatellite (μSAT CP-SAR). The CP-SAR is designed as the small, light in weight and low power consumption system. The CP-SAR sensor is developed to radiate and receives circularly polarized wave. This CP-SAR sensor will be applicable for land cover, disaster monitoring, snow cover, and oceanography mapping, etc...
Ground deformation studies based on Differential GPS (DGPS) measurements and Permanent Scatterers (PS) Interferometric analysis have been conducted in the seismically active area of the Cephallonia and Ithaca islands. DGPS measurements for the period 2001 to 2010 revealed horizontal component of deformation generally ranging from 3–8 mm/yr with the largest values at the western and southern parts...
In this paper, we proposed a wavelet-based methodology that enables to detect and diagnose the ionospheric anomalies associated with seismic activity. Wavelet transform and cross-wavelet analysis methods are used to detect and identify the spatio-temporal variability of ionospheric perturbation associated with Wenchuan Ms8.0 earthquake, 12 May 2008 in China, and to gain further insights into the dynamical...
Along track interferometric (ATI) synthetic aperture radar (SAR) has the capability of detecting moving targets and measuring the line-of-sight velocity of the target. With the ATI SAR, the current velocity map can be obtained by combining two perpendicular ATI data sets recorded over sea in rapid succession. In this paper, we describe how sea surface current can be mapped using airborne Ku-band SAR...
The advancement of remote sensing technology has contributed to a significant level of assistance in reducing nature's calamities, threatening both human lives and property in its immediate vicinity. Volcanic eruption is one of a kind where the dangerous environment surrounding it also causes great difficulties for close-up monitoring and surveillance. Differential Synthetic Aperture Radar Interferometry...
The ionosphere has been normally detected by traditional instruments, such as ionosonde, scatter radars, topside sounders onboard satellites and in situ rocket. However, most instruments are expensive and also restricted to either the bottomside ionosphere or the lower part of the topside ionosphere (usually lower than 800 km), such as ground based radar measurements. Nowadays, GPS satellites in high...
This paper presents the Passive Advanced Unit Synthetic Aperture instrument (PAU-SA), and some of the first experimental results: the use of pseudo-random noise signals for a complete baseline calibration and receivers' frequency response characterization, the use of a Kalman filter to better estimate the receivers' phase between internal calibrations, the imaging of an artificial point source at...
In the paper we proposed a comparison methodology between GPS delay and SAR Atmospheric Phase Screen (APS) in both differential and pseudo-absolute mode. ENVISAT ASAR and synchronous GPS campaign data in Como, Italy were collected and processed. APS from PSInSAR has been divided into even groups according to their height for analysis of stratification sensitivity. Then the stratification and assumed...
Traveling ionospheric disturbances (TIDs) induced by acoustic-gravity waves(AGWs) in the neutral atmosphere are subsequently observable in trans-ionospheric Global Navigation Satellite System (GNSS) measurements. Disruptive events on the Earth's surface, such as earthquakes, tsunamis and large explosions are one source of these disturbances. In this study, we apply a wavelet method to enhance the...
In the summer 2009 NASA Characterization of Arctic Sea Ice Experiment (CASIE09), the microASAR, a small LFMCW SAR, was operated on the NASA Sierra unmanned aerial system (UAS). An overview of the microASAR and its role in CASIE09 are described in [1, 2]. While the limitations in the motion measurements stored with the microASAR data during the CASIE09 mission originally precluded full motion compensation,...
This study shows that DInSAR methods able to detect the ground deformation which occurred because of underground material eruption, not only in nearby the center of eruption but also in the area far from the center of eruption (more than 4 kilometers apart). The DInSAR analysis can be considered as potential tool to monitor the mud volcano eruption disaster with low cost, especially to detect ground...
We present in this paper an empirical approach for the characterization of the internal layering of dry snow masses by means of GNSS-R. A forward model has been designed for reconstructing reflected waveforms given a dry snow profile and geometry (elevation and elevation-rate), as a sum of multiple responses from different layers. To extract the internal information, Fourier transforms of time series...
A ten-station GPS network extending in the broader area of Patras Gulf was established in 1994 to study the local and regional ground deformation of the area. The network has been fully occupied in three periods: August 1994, October 1996 and January 2006. A smaller scale GPS network being consisted of seven stations was installed in July 2008 across the Rio-Antirrio strait (eastern part of Patras...
The increase of storage and computing performance in embedded mobile platforms has provided better opportunities for the development of portable GPS software receiver. However, due to a large number of complex calculations in baseband operations, the real-time software receiver is still the biggest challenge, and in the baseband operations of the receiver, the largest time-consuming part is the satellite...
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