PROPAGATION FUNCTION AND MEAN PHASE VELOCITY OF ELECTROMAGNETIC WAVES AT ULTRALOW FREQUENCIES (RASPROSTRANENIYA I SREDNYAYA FAZOVAYA SKOROST' ELEKTROMAGNITNYKH VOLN NA SVERKHNIZKIKH CHASTOTAKH).
Abstract
On the basis of a statistical processing of daytime observation data at distances of 1000-1600 km from the source, the amplitude spectra of atmospherics and mean phase velocities of electromagnetic wave propagation near the earth's surface were obtained for a wide frequency range of 60 cps to 30 kc. The present study presents the results of analogous investigations of atmospheric spectra and mean phase velocities at night. The nighttime registration of atmospherics was carried out over a period of several years at Krasnaya Pakhra from 0040 to 0100 hours Moscow time. A detailed study of the received signals shows that their shapes at night are as varied as they are in the daytime. As indicated, seventyeight percent of the cases observed at night are A-type atmospherics, which are attenuating signals of oscillatory shape, less smooth than during the day, with superimposed hf signals. In 30% of the cases, the atmospheric is accompanied by a hf component, or tail. At night, 'tail' amplitude is relatively high even in reception from distances of 4000-5000 km. A complete harmonic analysis was carried out which permitted derivation of the formula: for type-A signals transmitted from the west and southwest of the point of observation at distances of 1000-4000 km from the source. (Author)
Document Details
- Document Type
- Technical Report
- Publication Date
- Apr 30, 1965
- Accession Number
- AD0462424
Entities
People
- A. G. Mikhaylova
Organizations
- Library of Congress