Study of the GNSS Signal Satellite-Specific Bias Stability Using Pseudorange Observations

There are many studies devoted to the problem of determining the delays of GNSS signals when emitted by the antenna of a navigation satellites and when received by the antenna of the receiver. Researchers' special attention is focused on developing algorithms for determining signal delays (code biases) of the Russian GLONASS satellites. The developed method for determining the values of such biases showed the fundamental possibility of its application. This study analyzed estimates of GLONASS satellite-specific bias over a long period - from September 2018 to June 2023. Pseudorange observations in the L1, L2 bands, high-precision orbits and clocks products and daily reports on the composition of the orbital constellation were used as initial data. Signal biases were estimated for GLONASS, GPS, and Galileo satellites operating during the observation period. The results showed cases of changes in satellite delay values, and the features of some satellites from the GLONASS orbital constellation were identified.