Meter Waves

radio waves with wavelengths of 1–10 m (frequency, 3 X 10⁷ to 30 X 10⁷ hertz). In terrestrial radio communication they propagate for short distances as direct and ground waves. They can propagate for longer distances as tropospheric waves through reflection or scattering by inhomogeneities, and also as ionospheric waves by reflection from meteor trails (or by reflection from the ionosphere in years of maximum solar activity). They are used for communication with space vehicles because they pass through the earth’s ionosphere. Their passage through the earth’s atmosphere is accompanied by refraction, partial absorption, and rotation of the plane of polarization.