What is 'skip' propagation?

Skip propagation refers to the phenomenon where radio waves are reflected back to Earth by the ionosphere, allowing communication over long distances. This occurs when certain conditions are met, such as the frequency of the radio signal being suitable for ionospheric reflection and the angle of incidence being appropriate. The ionosphere consists of layers of ionized particles that can refract radio waves, effectively bouncing them back toward the Earth instead of allowing them to continue traveling into space.

The ability to utilize skip propagation is particularly valuable for long-distance communication as it enables signals to be received far beyond the visual horizon. This method can lead to significant enhancements in radio communication, especially on frequencies that can be effectively reflected by the ionosphere.

In contrast, propagation through solid structures, water surfaces, or direct transmission without reflection does not involve the ionosphere's reflective properties and therefore does not allow for the same long-distance communication capabilities associated with skip propagation.