Skywave Propagation
Skywave propagation is a method of radio wave propagation used for long-distance communication, particularly in the high-frequency (HF) bands. In skywave propagation, radio waves are refracted or reflected back to Earth by the ionosphere, a region of charged particles in the Earth's upper atmosphere. When radio waves encounter the ionosphere, they can be bent or refracted depending on their frequency and the electron density of the ionospheric layers. This bending effect allows radio signals to follow the curvature of the Earth and travel beyond the line of sight, enabling communication over hundreds or thousands of kilometers. Skywave propagation is essential for HF communication, as it allows radio operators to communicate over long distances without the need for intermediate relay stations or satellite links. However, skywave propagation is subject to variations in ionospheric conditions, such as changes in solar activity, time of day, and geographical location, which can affect signal strength, propagation path, and reliability. Despite these challenges, skywave propagation remains a vital mechanism for global communication, particularly in amateur radio, maritime, and aeronautical communication, as well as for international broadcasting and emergency communication networks. s://en.wikipedia.org/wiki/Skywave_propagation