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Simultaneous microwave radar and radiometer observations of the ocean were conducted from aircraft during the ShoWEx'99 experiment. Both radar and radiometer wind dependences show similar signal growth with wind speed increase (except for the radiometer at vertical polarization and a near-Brewster angle). Analysis of the low-wind data shows that wind speed is a poor characteristic of the sea surface...
The land cover change detection method using the standard deviation of the backscattering coefficient was suggested. Comparing with the previous method using spatial information such as correlation coefficients, it reduced the commission errors in the agricultural areas. It was found that the detection accuracy increased when the target area was large, but each changed target was difficult to detect...
Airborne polarimetric and interferometric synthetic aperture radar (Pi-SAR) observation, conducted in the southern Sea of Okhotsk in February 2005, provided the opportunity to validate the retrieval of ice thickness distribution. In conjunction with the airborne SAR observation, in-situ ice thickness and ice- surface roughness measurements were carried out in the same area with ship-borne electromagnetic...
Fine resolution spotlight synthetic aperture radar (SAR) imagery collected on a circular flight path is used to investigate the variation in ship detection performance with respect to three fundamental radar parameters: the transmit/receive polarisation combination, the incidence angle and the azimuth angle. The polarisation combinations examined are HH, HV, VV, RR and cross-slant 45deg. Three different...
This paper formulates a new approach for ambiguous surface clutter suppression for ice sounding radars. While surface clutter from the non-orthogonal direction is reduced by means of Doppler and/or SAR processing, the residual surface contributions from across-track may still mask the reflection of internal layers and the bedrock, both coming from the nadir direction. The suggested approach involves...
The scanning hydrographic operational airborne LiDAR survey (SHOALS) consists of a bathymetric LiDAR system which provides high precision measurements of water depth. Even though the acquisition is focused on depth accuracy, the return signal, i.e. waveform, contains other relevant information because of integration signatures from the water surface, the water column and the sea-bed. This paper highlights...
Our paper proposes an approach for the extraction of stream channels from Airborne Laser Swath Mapping (ALSM) data. Recent advances in technology have led to high-resolution topographic data acquisition by means of airborne lidar (i.e. ALSM), which can yield Digital Elevation Model (DEM) datasets with horizontal resolutions of 1 m and vertical rms errors in the range of 10 - 15 cm. The extraction...
This paper deals with the methodology in the processing of airborne SAR data to measure glacier displacement fields. The possibility to retrieve a 2D displacement map of the deformation in slant-range geometry with an airborne platform is discussed. A new extended multisquint approach is proposed to simultaneously estimate residual motion errors and the along-track displacement of the glacier, while...
We acquired several data sets of polarimetrc SAR data in Sendai, Japan by airborne Pi-SAR system for fundamental research of radar polarimetry and interfereometry. Among these data acquisitions, two data sets were acquired in multiple flight paths in a short time period, and polarimetric SAR image acquired from different angles are available. We found very clear azimuth incident angle dependency of...
A new and fast algorithm for MTI/MTD processing is presented. This algorithm is based on a formation of SAR images from each channel and using these for separation between moving and stationary targets. First, the problem is described by means of a generalized model. Then, an inverse problem is formulated and some of its approximate solutions by means of the Fourier transform are given. The approximate...
Airborne radar observations of the sea surface at C- Band and small incidence angles are used to investigate some properties of the surface slope probability density function (pdf). The method is based on the analysis of the variation of the radar cross-section with incidence angle, assuming that the backscatter can be described by the Geometrical Optics theory. First, we show that roughness properties...
This paper discusses the design and construction of a compact, ultrafast, monostatic frequency modulated continuous wave (FMCW) millimeter-wave radar, operating at 94.75 GHz, intended to be used as a helicopter assisted landing sensor. A high speed direct digital synthesizer is used to generate the baseband FM signal. Custom transmitter/receiver baseband boards are designed to up/down-convert the...
This paper introduces a framework developed for image processing of synthetic aperture radar (SAR) images. It encapsulates features of modern hardware architectures, including symmetric and asymmetric multiprocessing, within an easy and intuitive to use application programming interface (API). The multiprocessing part is designed for unified usage of different architectures reaching from multicore...
Common efficient SAR processing algorithms are based on nominal operational conditions. Unfortunately, due to atmospheric turbulences and maneuvering errors, these conditions are often violated in real SAR systems. Hence, a crucial problem in most airborne SAR systems is the compensation of motion errors; if not corrected, the image quality will considerably degrade. A first-order motion compensation...
In this paper we show the results of an airborne differential SAR interferometry (DInSAR) experiment carried out over the Perugia area, center of Italy, by using the X-Band OrbiSAR system. Measurements on corner reflectors allowed us evaluating the system detection capability.
Along-track SAR interferometry has long been used to measure ocean surface currents with small velocities. There is a significant potential to employ this technique to detect slow ground moving targets with small radar cross-sections. In this paper, we present the development of a baseband signal simulator on ground moving target indication with along-track SAR interferometry. We summarize current...
This article aims at providing a comparison of polarimetric change detection indices from a practical point of view. Six polarimetric change detection indices were tested on L band EMISAR data over Norway. Tests included quantitative evaluation of change maps compared to a ground truth of changes, and qualitative evaluation by visual inspection. Contrast ratio and the Wishart test gave the best results...
UAVs from different countries and with different payloads have proven their capabilities within military applications. Future UAV employment in the civilian areas of surveillance (pollution, natural risks prevention, fire prevention), monitoring (traffic control, environmental monitoring, earth observation) and communication relays becomes unavoidable. Many payload configurations may be used in UAV...
A brief review is presented of published work on detection and imaging techniques based on matrix group theory for the scalar non-polarimetric two channel along track interferometer and the vector polarimetric two channel across track interferometer. The relevance to ATI of the vector theory for the across track interferometer is discussed as is the problem of extending the theory to the case of the...
The airborne radar system RAMSES collected data over the Sweden forest to investigate the capabilities of detection at P-band and influences of different SAR parameters like resolution, central frequencies, and look angle. During this campaign, circular trajectories have been performed in order to analyze the presence of anisotropic scattering from the targets at P-band. We show the treatment of two...
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