High frequency radio noise

Radio noise of atmospheric origin is discussed, and cosmic noise from sources external to the atmosphere is also considered. The basic features of generation and propagation of radio waves are addressed. The fundamentals of radiation from accelerated charges are reviewed insofar as they affect the radio noise level, and the role of the dipole above the earth, atmospheric effects, ionospheric propagation, and wave propagation through the ionosphere are examined. Quantitative measures of the radiation, including the spectrum of a single impulse, spectra of pulse sequences, and brightness temperature of extended noise sources, are examined. The source strength of sferics is discussed, including spectral densities, current moments, and mapping of sources. Noise from world-wide atmospherics, corona noise, atmospheric thermal noise, atmospheric noise at satellite altitudes, and special sources of atmospheric noise are briefly considered. Finally, radio noise from extraterrestrial sources, including cosmic noise maps, noise temperatures, and radio noise from the solar system, is covered.