Model study of the effect of the main ionospheric trough on oblique HF radiowave propagation

Modelling the main ionospheric trough using the Electron Density Assimilative Model (EDAM) with assimilated GPS TEC

“…This trough has not been studied so widely as the nightside main trough at mid-latitudes, but it has been suggested that it is an extension of the mid-latitude night-time trough back to earlier local times and higher latitudes (Pryse et al, 2005;Moffett and Quegan, 1983). Interest in the trough occurs in applications of ionospheric radio propagation, largely driven by the in-fluence of the feature on the propagation of high-frequency radio signals as shown along the oblique subauroral paths considered by Andreev et al (2006).…”

Physical and model interpretation of HF radio propagation on the St. Petersburg–Longyearbyen (Svalbard) path

“…10e), contains the section of the polar ionization peak at latitudes of 74-82°. Andreev et al (2006) has found that a short displacement of the main ionospheric trough by approximately 1 degree, can lead to the significant changes of the shape of oblique sounding ionograms obtained on the subauroral radio paths intersected the main ionospheric trough. Thus, it is expected that the high-latitude ionospheric density variations, calculated in the present study, have the appreciable effect on the oblique HF radio wave propagation.…”

“…Calculations by UAF EPPIM, Prolab-Pro and by other models and applied programs, for example, Dxaid (P. Oldfield), Dwprop (G. West), SNAPMax (C. MacKeand), Voacap (G. Lane et al) yield a possibility to derive the different propagation parameters on radio paths. But they do not allow to synthesize the OIS ionograms (Basler et al, 1988;Warrington and Stocker, 2003;Hughes et al, 2002;Stocker et al, 2002).…”

“…Further progress in describing the morphology and modeling of the MIT has been reviewed by Rodger et al (1992). The MIT may affect considerably the HF radio wave propagation (Blagoveshchensky and Borisova, 1995;Andreev et al, 2006;Warrington and Stocker, 2003). It is known that the main ionospheric trough is of fairly repeatable occurrence in the mid-latitude ionosphere and can exist for a long time, especially in winter months.…”

Using IRI and GSM TIP model results as environment for HF radio wave propagation model during the geomagnetic storm occurred on September 26–29, 2011

“…During the past decade, few studies of HF radio wave ray-paths have been done using both numerical ionospheric and RWP models (Andreev et al, 2006(Andreev et al, , 2007a(Andreev et al, , 2007bBlagoveshchensky et al, 2009;Kotovich et al, 2010). The results obtained in these studies include: (1) the model simulation of the HF radio wave propagation in the vicinity of the main ionospheric trough (Andreev et al, 2006;2007b); (2) calculation of oblique sounding ionograms allowing the interpretation of experimental oblique ionograms (Andreev et al, 2007a;Blagoveshchensky et al, 2009);and (3) a model study of the main characteristics of oblique sounding ionograms (Kotovich et al, 2010).…”