Large-scale traveling ionospheric disturbances registered using oblique-incidence sounding over north-eastern region of Russian Federation

Using experimental data obtained over oblique-incidence sounding (OIS) paths we analyze parameters of large-scale traveling ionospheric disturbances (LS TIDs) registered during several days from October, 2015, till March, 2016. The transmitters are located near Magadan (60.1°N, 150.7E), Khabarovsk (47.6N, 134.7E) and Norilsk (69.4N, 88.4E). The receiver is located near Tory, Buryatia (51.8N, 103E). OIS experimental data processing was carried out by the program of automatic interpretation of OIS ionograms. This program permits to determine different modes of HF radio wave propagation. In this study LS TIDs are considered as significant wave-like variations of electron density of F2 ionospheric region near the middle point of the OIS path. Such electron density variations are appeared in corresponding wave-like changes of maximum observed frequencies reflected from F2 ionospheric layer by one hop (MOF1F2). In our study we determine mean amplitudes and periods of LS TIDs for quiet and magnetically disturbed conditions using relative deviations of MOF1F2 from median values. The electron density profiles near the middle point of OIS propagation paths have been calculated also. The analysis of the storm-time generated LS TID in November, 07, 2015, has been carried out.