Characterization of the PAZ X band SAR Using the HITCHHIKER Ground Receiver

<div>With the start of the Spanish PAZ system, another earth observation satellite has become available to the scientific community. Following the launch of the PAZ science phase, we performed a number of ground experiments using different modes of the satellites SAR instrument, measuring the transmitted radar signal as well as its ground reflections using the HITCHHIKER receiver. The data acquired in these experiments is analyzed and used in collaboration with the PAZ calibration team at INTA to characterize the PAZ instrument and thus verify the system calibration. Further we obtained bistatic radar images from the data of the HITCHHIKER ground receiver.</div>

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X-Band Full MMIC QPSK Modulator with Direct Oscillator for the Spot 5 Earth Observation Satellite Payload

10.1109/euma.1999.338354 ◽

1999 ◽

Cited By ~ 1

Author(s):

N. Cartier ◽

M. Hussonnois ◽

B. Tranier ◽

P. Maynadier ◽

E. Midan ◽

...

Keyword(s):

Earth Observation ◽

X Band ◽

Earth Observation Satellite ◽

Spot 5

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X-Band Radar as a Tool to Determine Spectral and Single Wave Properties

Volume 3: Safety and Reliability; Materials Technology; Douglas Faulkner Symposium on Reliability and Ultimate Strength of Marine Structures ◽

10.1115/omae2006-92015 ◽

2006 ◽

Cited By ~ 5

Author(s):

Konstanze Reichert ◽

Katrin Hessner ◽

Jens Dannenberg ◽

Ina Traenkmann

Keyword(s):

Real Time ◽

Ocean Waves ◽

Sea Surface ◽

Surface Elevation ◽

Radar Signal ◽

Sea State ◽

Single Wave ◽

Radar Images ◽

X Band ◽

Wave Properties

The Wave Monitoring System WaMoS II was developed for real time measurements of directional ocean waves spectra to monitor the sea state from fixed platforms in deep water or coastal areas as well as from moving vessels. The system is based on a standard marine X-Band radar used for navigation and ship traffic control. WaMoS II digitises the analogous radar signal and analyses the sea clutter information to obtain directional wave spectra from the sea surface in real time even under harsh weather conditions and during night. Spectral sea state parameters such as significant wave height, peak wave period and peak wave direction both for wind sea and swell are derived. Within the EU funded project ‘MaxWave’ and the German project ‘SinSee’ new algorithms were developed to determine sea surface elevation maps from radar images which are used to investigate the spatial and temporal evolution of single waves simultaneously. In this paper a short overview describes the calculation of surface elevation maps and the detection of individual waves. Considering two case studies, the results of spatial single wave detection and corresponding temporal single wave properties are compared and discussed. Individual wave parameters derived from radar images are compared to individual waves measured by a buoy. An application of the method to characterise extreme sea states is discussed.

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Coherent backscatter enhancement in bistatic Ku-/X-band radar observations of dry snow

10.5194/tc-2021-358 ◽

2021 ◽

Author(s):

Marcel Stefko ◽

Silvan Leinss ◽

Othmar Frey ◽

Irena Hajnsek

Keyword(s):

Electromagnetic Waves ◽

Bistatic Radar ◽

Water Ice ◽

Enhanced Backscattering ◽

Radar Systems ◽

X Band ◽

Solar System Bodies ◽

Coherent Backscatter ◽

Ku Band

Abstract. The coherent backscatter opposition effect (CBOE) enhances the backscatter intensity of electromagnetic waves by up to a factor of two in a very narrow cone around the direct return direction when multiple scattering occurs in a weakly absorbing, disordered medium. So far, this effect has not been investigated in terrestrial snow in the microwave spectrum. It has also received little attention in scattering models. We present the first characterization of the CBOE in dry snow using ground-based and space-borne bistatic radar systems. For a seasonal snow pack in Ku-band (17.2 GHz), we found backscatter enhancement of 50–60 % (+1.8–2.0 dB) at zero bistatic angle and a peak half-width-at-half-maximum (HWHM) of 0.25°. In X-band (9.65 GHz), we found backscatter enhancement of at least 35 % (+1.3 dB) and an estimated HWHM of 0.12° in the accumulation areas of glaciers in the Jungfrau-Aletsch region, Switzerland. Sampling of the peak shape at different bistatic angles allows estimating the scattering and absorption mean free paths, ΛT and ΛA. In the VV polarization, we obtained ΛT = 0.4 ± 0.1 m and ΛA = 19 ± 12 m at Ku-band, and ΛT = 2.1 ± 0.4 m, ΛA = 21.8 ± 2.7 m at X-band. The HH polarization yielded similar results. The observed backscatter enhancement is thus significant enough to require consideration in backscatter models describing monostatic and bistatic radar experiments. Enhanced backscattering beyond the Earth, on the surface of solar system bodies, has been interpreted as being caused by the presence of water ice. In agreement with this interpretation, our results confirm the presence of the CBOE at X- and Ku-band frequencies in terrestrial snow.

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