Earth–ionosphere waveguide
= Earth–ionosphere waveguide
{wiki=Earth–ionosphere_waveguide}
The Earth–ionosphere waveguide is a natural waveguide that forms between the Earth's surface and the ionosphere, which is a layer of the atmosphere filled with ionized gases located approximately 30 miles (about 48 kilometers) above the surface of the Earth and extending up to about 600 miles (about 965 kilometers) in altitude. This waveguide is particularly significant for the propagation of radio waves.