Accession Number : AD0694870

Title :   NONVERTICAL PROPAGATION AND DELAYED-ECHO GENERATION OBSERVED BY THE TOPSIDE SOUNDERS,

Corporate Author : COMMUNICATIONS RESEARCH CENTRE OTTAWA (ONTARIO)

Personal Author(s) : Muldrew,D. B.

Report Date : 05 MAR 1969

Pagination or Media Count : 11

Abstract : Knowledge of the topside ionosphere resulting from studies of nonvertical propagation, such as scatter from ionization irregularities and minitroughs, hemispherically conjugate echoes, combination modes, multiple-hop propagation, unusual Z-wave propagation, and whistler-mode propagation, is reviewed. From these studies there appear to be two major types of magnetic field-aligned ionization irregularities: a thick type and a thin type. The thick type has a thickness of tens or hundreds of kilometers and occurs both near the auroral zone and at latitudes corresponding to the equatorial anomaly. The thin type has a thickness of a few hundred meters and may extend thousands of kilometers along a field line. At high latitudes the thin type has a tubular cross section, may have an electron density either greater or less than the ambient, and may result from fluxes of energetic particles; at low latitudes the thin type has an electron density deviation of the order of 1 percent or less. The thin type of ionization irregularity supports propagation which is responsible, at some distance from the satellite, for two different delayed-echo phenomena. (Author)

Descriptors :   (*SCIENTIFIC SATELLITES, ATMOSPHERIC SOUNDING), (*ELECTROMAGNETIC RADIATION, PROPAGATION), IONOSPHERIC DISTURBANCES, IONIZATION, BACKSCATTERING, ELECTROSTATIC FIELDS, WHISTLERS, ELECTRON DENSITY, RESONANT FREQUENCY, SPIKES, CANADA

Subject Categories : Atmospheric Physics
      Radiofrequency Wave Propagation
      Unmanned Spacecraft

Distribution Statement : APPROVED FOR PUBLIC RELEASE