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The sampling limitations of a single nadir-looking ocean altimeter have long been known, and multiple altimeter missions and bistatic altimeter configurations have been proposed as solutions. In this paper we suggest an alternate method that ovecomes the sampling issue through the combined use of nadir-looking altimetery and off-nadir radar interferometry.
We present an overview of Space Interferometry Mission with a particular attention to its metrology subsystem.
A short tutorial covering the basics of astrometry and interferometry relating to the SIM mission is presented.
The synthetic-aperture radar interferometry technique is used to detect the migration of the limit of tidal flexing, or hinge line, of the floating ice tongue of Petermann Gletscher, a major outlet glacier of north Greenland.
In this paper we will discuss the prospects for global astrometric measurements with the Space Interferometry Mission (SIM). SIM will perform four microarcsecond astrometric measurements onpoint-like objects as dim as 20th magnitude using optical interferometric techniques with a 10m baseline.
ERS radar interferometry is a powerful new technique to map the grounding line of outlet glaciers, or more precisely to located the limit of tidal flexing of their floating sections, or hinge line.
The field of synthetic aperture radar changed dramatically over the past decade with the operational introduction of advanced radar techniques such as polarimetry and interferometry.
Interferometry at radio frequencies between Earth-based receivers separated by intercontinental distances had made significant contributins to astrometry and geophysics during the past three decades, Analyses of such very long baseline interferometric (VLBI) experiments now permit measurements of relative positions of points on the Earth's surface, and angles between celestial objects, at the levels of 1cm and 1 nanoradian, respectively. The relative angular positions of extragalactic radio sources inferred from this technique presently form the best ralization of an inertial reference frame. This review summarizes the current theoretical models that are needed to extract results from the VLBI observables at such levels of accuracy.
A dramatic short term speed up of the Ryder glacier has been detected using satellite radar interferometry. The accelerated flow represents a substantial, though short-lived, change in the ice discharge from this basin. We believe that meltwater was involved in this event, either as an active participant, as meltwater-filled lakes on the surface of the glacier drained during the period of rapid motion.
In radar interferometry, two phase-coherent radar images, obtained.
In this talk we present results of a repeat-pass SAR interferometry experiment performed in June 1993 near Portage, Maine. Differential GPS data accurate to +/-10cm were acquired to aid in motion compensation and geolocation of targets in the imagery. The experiment and data analysis will be discussed, and results will be shown during the presentation.
Narrow-angle astrometry with long-baseline infrared interferometers can provide extremely high accuracies as required for indirect planet detection. Narrow-angle asrometric interferometry exploits the properties of atmospheric turbulence over fields smaller than the interferometer baseline divided by the atmospheric scale height.
At depth, many fold-and-thrust belts are composed of a gently dipping, basal thrust fault and steeply dipping, shallower splay faults that terminate beneath folds at the surface. Movement on these buried faults is difficult to observe, but synthetic aperture radar (SAR) interferometry has imaged slip on at least 600 square kilometers of the Shahdad basal-thrust and splay-fault network in southeast Iran.
We discuss the design, current status, and ongoing development of a cryogenic delay line for long-baseline direct-detection interferometry in the far-infrared.
The Space Interferometry Mission (SIM) will be the NASA Origins Program's first space based long baseline interferometric observatory.
The purpose of interferometry in the ELITE mission is to measure the differential displacement between the two inertial sensors mounted in the spacecraft.
The primary limitation to ground-based optical/IR interferometry is the turbulent atmosphere, which limits sensitivity by restricting the coherence volume, limits imaging accuracy by corrupting the fringe phase, and limits astrometric acuracy by corrupting the angel of arrival.
Study of the September-October 1997 Umbria-Marche earthquakes that took place in Italy. Use joint inversion of GPS and SAR interferometry data.