Accession Number : AD0294698

Title :   OBSERVATIONS OF FIELD-ALIGNED IRREGULARITIES AND TRANSEQUATORIAL PROPAGATION

Corporate Author : QUEENSLAND UNIV BRISBANE (AUSTRALIA)

Personal Author(s) : THOMAS,J.A. ; DEARDEN,E.W.

Report Date : MAR 1962

Pagination or Media Count : 1

Abstract : The work carried out at Brisbane in connection with investigations of field-aligned irregularities in the ionosphere and trans-equatorial propagation of radio waves is summarized. Information is given regarding the extent of such irregularity patches, their movements and the correlations of the observed radar echoes from these irregularities with other ionospheric and ge physical phenomena. An association is proposed between large E-W elongated bands of the irregularities, Van Allen outer belt radiation counts and an F-region anomaly already associated with the observation of red airglow arcs. The scintillation of radio transmissions passing through the irregularities at directions close to the field direction is probably the most sensitive means of detection of such irregularities. Anomalous trans-equatorial propagation of H.F. signals is associated with tilted reflection of very low angle radiation and occurs near the time of passage of the evening equatorial rise in F-region heights. At mid-latitude stations, an intervening normal 1F hop before the anomalous propagation hop may well exert a controlling influence on the use of this type of propagation. (Author)

Descriptors :   *IONOSPHERIC DISTURBANCES, *RADIO WAVES, BACKWARD WAVE OSCILLATORS, DETECTION, HIGH FREQUENCY, PROPAGATION, RADAR CROSS SECTIONS, SCINTILLATION COUNTERS, SENSITIVITY, VAN ALLEN RADIATION BELT

Distribution Statement : APPROVED FOR PUBLIC RELEASE