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High frequency (HF) radio band is important for the long-range communications and over-the-horizon surveillance, particularly in the polar cap region where the ground infrastructure may be limited. However, the space weather events drastically affect the high frequency radio wave propagation so that the ability to provide now-casting and forecasting of HF radio wave absorption is important for users...
The analytical solution to the spaced position and frequency coherence functions of the GNSS type fields propagating through the ionosphere is given. The explicitly constructed coherence functions are obtained for the quadratic structure function of the electron density fluctuations of the ionosphere and the inhomogeneous background ionosphere, where the dependence of the plasma frequency along the...
Ionospheric scintillations can not only reduce the accuracy of GPS/SB AS receiver pseudorange and carrier phase measurements but also result in a complete loss of lock on a satellite. Thus it is important to be able to investigate, model and mitigate scintillation effects. Thus, a transionospheric propagation model has been developed which can calculate frequency spectra (power spectra) of the phase...
A fast and accurate method of determining path delay and phase advance and range error between any two satellites for L-band frequencies has been determined. The method takes into account the bending of the ray path due to refraction by both vertical and horizontal gradients as well as the effect of the geomagnetic field and the actual profile of the electron density and its gradients along the path...
In satellite positioning, a linear combination of 2 signals is used to eliminate the error due to the background ionosphere. State-of-the-art semi-codeless techniques rely on cross-correlation of the signals received at L1 and L2. Thus it is important to determine how well these signals are correlated. Lack of correlation will also introduce range error in the 2-frequency correction. A significant...
A transionospheric propagation model has also been developed which can calculatee frequency spectra (power spectra) of the phase and level (log-amplitude) fluctuations in a transionospheric channel of propagation containing time-varying electron density irregularities which produce scintillations and is valid even for strong scintillation conditions. Computer codes have been created to calculate time...
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