An experiment of GPS+GLONASS common-view time transfer using new multi-system receivers

In this paper we report a new experiment of the combined use of GPS and GLONASS for international time and frequency transfer using TTS-3 multi-channel multisystem receivers. The investigation was carried out on a baseline of about 1400 km between the Astrogeodynamical Observatory (AOS) in Poland and Bureau International des Poids et Mesures (BIPM) in Sèvres. Unlike GPS, almost every GLONASS satellite works at a different basic frequency. In order to study the effects of these different frequencies on the common-view links, the investigations were carried out for every individual satellite. The results confirm that a combined use of GPS and GLONASS is feasible, despite the differences between the two systems. The use of two systems in multi-channel mode increases the number of observations by a factor of 28 in comparison to a single-channel-one-system mode, resulting in improved time and frequency comparisons.