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This paper proposes a novel speckle reduction method that combines an advanced statistical distribution with spatial contextual information for SAR data. The method for despeckling is based on a Markov random field (MRF) that integrates a K-distribution for the SAR data statistics and a Gauss-MRF model for the spatial context. These two pieces of information are combined based on weighted summation...
Focusing on the issue of echo data acquire approach in bistatic SAR system. In this paper, the key technology of echo sampling window synchronization is introduced, the effect of echo sampling window synchronization error to the echo data and image performance are analyzed, an adaptive echo sampling window synchronization approach based on amplitude demodulation and phase compare is proposed, which...
The quality of Synthetic Aperture Radar image is affected by the deviation of radar platforms from the nominal straight line which is usually measured based on hardware such as Inertial Measurement Unit and Global Position System with high accuracy. Because of limited budget, many SAR systems cannot carry those expensive equipments. Based on the 3-D Geometry model of the motion error analysis, a new...
This paper addresses the problem of object localization using only angle-of-arrival (AoA) data from satellites. Traditionally, this is performed by a triangulation algorithm (TA) that minimizes the distances between the estimated object location to all lines-of-sight representing measurements of the object. However, when observing objects from satellites, the differences in distance from each satellite...
The NASA Soil Moisture Active and Passive (SMAP) mission will measure soil moisture with a combination of L-band radar and radiometer measurements. We present an assessment of the expected impact of radio frequency interference (RFI) on SMAP performance, incorporating projections based on recent data collected by the Aquarius and SMOS missions. We discuss the impacts of RFI on the radar and radiometer...
Once launched in late 2014, NASA's Soil Moisture Active Passive (SMAP) mission will use a combination of a four-channel L-band radiometer and a three-channel L-band radar to provide high resolution global mapping of soil moisture and landscape freeze/thaw state every 2-3 days. These measurements are valuable to improved understanding of the Earth's water, energy, and carbon cycles, and to many applications...
An Observing System Simulation Experiment (OSSE) for the Aquarius/SAC-D mission has been developed for assessing the accuracy of soil moisture retrieval from passive and active L band. So far, this OSSE has been successfully exploited to study the artifacts in the retrieved soil moisture associated to: (1) uncertainties and aggregation of the ancillary parameters needed for the retrieval and (2) instrumental...
The effect of topography on remote sensing at L-band is examined using the co-located Aquarius radiometer and scatterometer observations over land. A correlation with slope standard deviation is demonstrated for both the radiometer and scatterometer at topographic scales.
An integrated soil moisture retrieval algorithm is presented in this work wherein both radar and radiometer measurements are used simultaneously to retrieve surface soil moisture. This method is applied to bare rough surfaces with varying soil moisture and roughness distributions. A thresholding method based on physical models of scattering and emission is presented to obtain equivalent estimated...
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