Sounding of the ionosphere disturbed by the “Sura” heating facility radiation using signals of the GPS satellites

Abstract

We present the results of experimental studies of the properties of the plasma-density disturbances created during heating of the ionospheric F 2 region by high-power HF radio waves radiated by the "Sura" heating facility (Radiophysical Research Institute, Nizhny Novgorod). These experiments are specific in that they were performed in a sunlit (daytime) ionosphere when the generation of ionospheric turbulence has specific features and the turbulence intensity level is low enough. The plasma-density disturbances induced by high-power HF radio emission were sounded by signals of the GPS satellites, the line of sight to which crossed different parts of the disturbed ionosphere region. Threshold powers of the excitation of artificial plasma-density variations as well as spatial, temporal, spectral, and energy characteristics of the generated disturbances are determined.

GPS-TEC variations, generated in midlatitude and highlatitude ionosphere by powerful HF-heating

“…1a,b). As it was stated in [7], such TEC behavior is determined by plasma density growth at heights of about of 130 -180 km when the ionosphere is pumped by powerful HF waves.…”

“…These irregularities should have a considerable effect on the VHF/UHF/L-band radio waves propagating through the heated area of the ionosphere. Recently, methods for sounding of the heated ionosphere by radio signals from high-orbiting navigational GNSS satellites at frequencies 1.2-1.5 GHz started to develop [4][5][6][7]. In this paper, we present the experimental results of the influence of electron density perturbations produced by the high-frequency heating of the ionosphere on the GNSS signals at the Sura (Radiophysical Research Institute, N. Novgorod, Russia) and EISCAT/Heating (Tromsø, Norway) facilities .…”

Peculiarities of Excitation of Large-Scale Plasma Density Irregularities During Modification of the Ionospheric F 2 Region by High-Power HF Radio Waves

“…Thus, it can be concluded that the region with a strong decrease in TEC in the south-west direction has sizes no less than 30 km. Note that, according to [23], such a cavity with depleted plasma density is not detected, as a rule, at the northern edge of the disturbed region. This fact is evidence that the observed phenomenon belongs only to the magnetic zenith region for the pump wave.…”

“…The method of sounding of the disturbed ionospheric region by radio signals of the navigation satellites GPS/GLONASS has recently been widely used at the SURA facility at frequencies of 1.2 to 1.6 GHz [23,24]. The signals from these satellites are received using several two-frequency receivers installed both on the territory of the SURA heater (having the coordinates 56.15 • N, 46.1 • E) and around it at a distance of up to a few tens of kilometers.…”

Mutual Allocation of the Artificial Airglow Patches and Large‐Scale Irregularities in the HF‐Pumped Ionosphere

“…Propagated through the heated region, satellite's microwave signals acquire an additional phase increment stipulated by the dispersion of the radio waves in the ionospheric plasma and linearly related to the total electron content (TEC) on the propagation path (slant TEC, or STEC). Since 2007 this method has been used to determine the STEC in the ionosphere during HF pumping at HAARP (Kendall et al, ; Milikh et al, ; Najmi et al, ; Pedersen et al, ) and SURA (Frolov et al, ; Kunitsyn et al, ; Ryabov et al, ) facilities. In this case, the satellite signal propagating to ground‐based receiver through a main lobe of the heating facility antenna pattern makes a radio scan of the HF‐induced ionospheric irregularities.…”