Premium
Airborne Field Strength Measurements in the Region of the NPM Antipode
Author(s) -
Rogerson J. E.
Publication year - 1967
Publication title -
radio science
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.371
H-Index - 84
eISSN - 1944-799X
pISSN - 0048-6604
DOI - 10.1002/rds196726581
Subject(s) - antipodal point , sunset , noon , midnight , sunrise , field strength , field (mathematics) , meteorology , physics , transmitter , geodesy , geology , atmospheric sciences , optics , mathematics , telecommunications , magnetic field , geometry , astronomy , computer science , quantum mechanics , pure mathematics , channel (broadcasting)
In July 1963, the Naval Research Laboratory and the Navy Electronics Laboratory conducted a joint experiment in the vicinity of the antipode of the yery low frequency transmitter NPM (19.8 kHz). An analysis of data collected by the Naval Research Laboratory during aircraft flights in the immediate vicinity of the antipode dunng this experiment is presented. A definite increase in field strength in the antipodal region was observed; inverse square root of distance variations in the field strengths over sections of the antipodal area were seen. A diurnal pattern in which highest field strengths occurred at local sunrise, lowest field strengths at local sunset, and intermediate signal levels at local noon and midnight was observed. Inferences of antipodal movement could be drawn from the data. The antipodal situation appeared to be complex, and further study is needed before a complete understanding can be obtained.