Currently polar ionosphere is of great interest. This is connected with creation of global model of ionospheric storms and providing stable navigation in polar region. Currently dual- and multi-frequency GNSS phase measurements have been utilized widely and these mea- surements combination yields us current TEC-values along all SV’s line-of-sights in view. One of the main parameters is stability of phase measurements and their noise level. We carry out the GNSS signal monitoring campaign under the polar ionosphere condition (in Taimyr cape, Russia) in 2013. JAVAD Delta-G3T receiver was used. We observed amount of the rapid and sharp phase acceleration variations. The absolute value of these variations were as much as 30–40% up to 2–2.5 times higher in comparison the background level for both GPS and GLONASS signals. In some cases we found a strong positive correlation between the phase acceleration variations and TEC variations in the variation frequency band of 0.08–1 Hz. It is well known that this frequency band relates to the 1-st Fresnel zone sized ionospheric irregularities. On the other hand we found some cases when there was no an obvious correlation between the 0.08–1 Hz TEC-variations and the phase acceleration variations. In these cases the phase acceleration variations could be inspired by the SV’s reference oscillator frequency drift. In order to separate all the observed phase acceleration variations according to they physical origin we arranged a new measurement campaign of both GPS and GLONASS signals in Norilsk (69◦ N, 88◦ E) and Irkutsk (52◦ N, 104◦ E). Additionally we used Moscow (55◦ N, 37◦ E) data. This report is devoted to discussion of the main results of the campaign data treatment.