Sounding Methods in HF Sky Wave Communications

• Main Authors: Orga, Ferran, Alsina‐Pagès, Rosa M., Bergadà, Pau, Hervás, Marcos
• Format: Other/Unknown Material
• Language: English
• Published: Wiley 2022
• Subjects: Antarc*; Antarctica
• Online Access: http://dx.doi.org/10.1002/047134608x.w8431; https://onlinelibrary.wiley.com/doi/pdf/10.1002/047134608X.W8431; https://onlinelibrary.wiley.com/doi/full-xml/10.1002/047134608X.W8431

Abstract The existence of the ionosphere as an electrically charged region in the atmosphere was suggested way back in 1839 by Friedrich Gauss. However, it was not until the 1920s that Edward Appleton proved that signals could be received without line of sight anywhere on the planet when emitting in high‐frequency ranges and by means of the ionosphere. The study of the ionosphere has widely attracted the interest of communication researchers due to its complexity regarding time and frequency dispersion. In this chapter, the techniques to characterize the ionospheric HF channel are reviewed. Also, the outcomes of the most relevant research projects working on that issue are provided. This chapter also gives the calculations required to conduct the study of channel availability, signal‐to‐noise ratio, multipath delay spread, and Doppler spread. Finally, the outcomes of these calculations are provided for a real case study involving a 12 760‐km long‐haul link from Antarctica to Europe.