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arXiv · 1406.4846

A geometric delay model for Space VLBI

Shi-Long Liao·Zheng-Hong Tang·Zhao-Xiang Qi
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Abstract

A relativistic delay model for space very long baseline interferometry (hereafter SVLBI) observation of sources at infinite distance is derived. In SVLBI, where one station is on a spacecraft, the orbiting station's maximum speed in an elliptical Earth orbit is much bigger than the ground VLBI (here after GVLBI), leading to a higher delay rate . The delay models inside the VLBI correlators are usually expressed as fifth-order polynomials in time that good for a limited time interval, which are evaluated by the correlator firmware and track the interferometer delays over a limited time interval. The higher SVLBI delay rate requires more accurate polynomial fitting and evalution, more frequent model updates.

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Shi-Long Liao, Zheng-Hong Tang, Zhao-Xiang Qi. 2014-02-14. A geometric delay model for Space VLBI. https://arxiv.org/abs/1406.4846

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