The results of investigations into the high-frequency radio wave propagation in the disturbed ionosphere being performed at the Department of Radio Physics of St. Petersburg State University are presented. The disturbed ionosphere is treated as the ionosphere containing reasonably expressed medium scale inhomogeneites (as in the polar or equatorial ionosphere), as well as strong enough fluctuations of the electron density, which may results in the regime of the high-frequency field strong scintillation when propagating through the ionosphere. Propagation in the ionospheric reflection channel (frequencies of the order of 10MHz) and transionospheric channel (frequencies of the order of 100 and 1000MHz) is discussed.