Precise VLBI/GNSS ties with micro-VLBI

TL;DR

This paper introduces a microwave technique that enables precise local tie measurements between GNSS and VLBI stations by converting GNSS signals into a VLBI-compatible format, demonstrated through successful observations.

Contribution

The paper presents a novel method to integrate GNSS receivers into VLBI networks using microwave signal transfer, enhancing local tie measurement accuracy.

Findings

Detected strong interferometric signals from radiogalaxies and GNSS satellites.

Successfully demonstrated the feasibility of the proposed technique.

Showed potential for improved local tie measurements in geodesy.

Abstract

We present here a concept of measuring local ties between collocated GNSS and VLBI stations using the microwave technique that effectively transforms a GNSS receiver to an element of a VLBI network. This is achieved by modifying the signal chain that allows to transfer voltage of the GNSS antenna to a digitizer via a coaxial cable. We discuss the application of this technique to local tie measurement. We have performed observations with a GNSS antenna and FD-VLBA radiotelescope and detected a strong interferometric signal from both radiogalaxies and GNSS satellites.