WVRs for the “Quasar” Network

G. Ilin, V. Bykov, V. Stempkovsky, A. Shishikin

IVS 2014 General Meeting Proceedings "VGOS: The New VLBI Network", A. Finkelstein, D. Behrend (Eds), 102–105 (2014)

Keywords: Water vapor radiometers, wet delay

Abstract

A prototype for dual frequency water vapor radiometers (WVRs) was developed at IAA and tested at the “Svetloe” observatory for more than a year. It was constructed according to the IAA plan to have near real time information about the zenith tropospheric wet delay (ZWD) in “Quasar” network observatories for use in VLBI data processing. Another two WVRs of the same type will be constructed in 2014 for the “Badary” and “Zelenchukskaya” observatories. The WVR prototype demonstrated very stable metrological characteristics in time intervals of several months. The values of ZWD assessed by WVR were compared with the same values determined from GNSS observations. The difference between the GNSS and WVR ZWDs is practically equal to zero with an accuracy of up to 3–5 mm (r.m.s), except for periods of intensive rain. This result was achieved due to precise measurements of the atmosphere brightness temperature.