The use of dual-polarized broad beam antennas to determine the extraterrestrial intensity of the cosmic radio noise at high frequencies

The existing evidence indicates that at high frequencies, the cosmic radio noise outside the earth\´s ionosphere is essentially randomly polarized. However, on passing through an absorbing ionosphere the extraordinary mode (X-mode) signal will suffer more absorption than the ordinary mode (O-mode) signal. The quasi-longitudinal approximation of the classical Appleton-Hartree form of the magnetoionic equations gives the relationship for the non-deviative absorption A, in decibels, at an effective operating angular frequency .