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Precision Geodesy via Radio Interferometry
Science, 1972Very-long-baseline interferometry experiments, involving observations of extragalactic radio sources, were performed in 1969 to determine the vector separations between antenna sites in Massachusetts and West Virginia. The 845.130-kilometer baseline was estimated from two separate experiments.
H F, Hinteregger +9 more
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Reviews of Geophysics, 1983
In the previous Quadrennial Report, Clark [1979c] concluded that, after slightly more than one decade of development and refinement, the technique of Very Long Baseline Interferometry (VLBI) had “come of age.” However, by the close of 1978, only the most tentative first steps had been taken by the geodetic community toward the deployment and operation ...
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In the previous Quadrennial Report, Clark [1979c] concluded that, after slightly more than one decade of development and refinement, the technique of Very Long Baseline Interferometry (VLBI) had “come of age.” However, by the close of 1978, only the most tentative first steps had been taken by the geodetic community toward the deployment and operation ...
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Positioning of Geostationary Satellite by Radio Interferometry
IEEE Transactions on Aerospace and Electronic Systems, 2019There are several perturbations that force the satellite orbit to deviate from the elliptical form. To cope with these perturbations, station keeping is applied. For accurate station keeping, determination of the true satellite orbit is necessary. Radio interferometry is one of the techniques used for determining azimuth and elevation look angles of a ...
Mohammad Sadeghi +2 more
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Radio-frequency low-coherence interferometry
Optics Letters, 2014A method for retrieving low-coherence interferograms, based on the use of a microwave photonics filter, is proposed and demonstrated. The method is equivalent to the double-interferometer technique, with the scanning interferometer replaced by an analog fiber-optics link and the visibility recorded as the amplitude of its radio-frequency (RF) response.
Carlos R, Fernández-Pousa +3 more
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Regularization methods in radio interferometry
Radiophysics and Quantum Electronics, 2007The problem of image retrieval in radio interferometry is a classical example of an ill-posed problem. In this paper, we consider a new approach to the radio-interferometric imaging based on regularization, which is computationally more flexible. A new type of a weighting function suitable for managing the interferometer antenna pattern is obtained ...
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Angular Position Determination of Spacecraft by Radio Interferometry
Proceedings of the IEEE, 2007This paper describes a variety of interferometric techniques that may be used for measuring the angular location of a spacecraft with respect to natural celestial radio sources or another spacecraft. The differential propagation time-delay techniques largely cancel the common error sources and normally achieve low angular coordinate errors.
Gabor Lanyi +2 more
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A laboratory-based microwave radio-interferometry testbed
IGARSS 2003. 2003 IEEE International Geoscience and Remote Sensing Symposium. Proceedings (IEEE Cat. No.03CH37477), 2004The Goddard Radio Interferometry Testbed (GRIT) is an adaptable platform for laboratory testing of Synthetic Thinned Array Radiometers (STAR). Using this testbed, we demonstrate that the Doppler radiometer can image a point source in an observed scene.
M. Moriarty +3 more
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General relativity and radio interferometry
The Physics Teacher, 1976A summary is given of the radiowave bending experiment conducted at NRAO to check the validity of Einstein’s General Relativity theory ...
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A Scheme to Measure Lateral Velocity by Radio Interferometry
IEEE Geoscience and Remote Sensing Letters, 2016It is difficult to acquire lateral velocity in the current radar applications. In order to obtain the velocity vector, two or more radar sites are needed. However, it is of great cost, and it is difficult to achieve real-time measurement. In this letter, a scheme is proposed to measure lateral velocity based on radio interferometry with which two ...
Chuan Li 0005 +2 more
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Geodesy by Radio Interferometry
1977By the use of radio-interferometric observations of extragalactic radio sources it is possible to determine all three components of an interferometer “baseline” vector, which extends from one radio antenna to another, with respect to an inertial coordinate system.
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