Accession Number : ADA061570


Title :   Effects of Strong Local Sporadic E on ELF Propagation.


Descriptive Note : Interim rept. 1 Feb-1 Jun 78,


Corporate Author : NAVAL OCEAN SYSTEMS CENTER SAN DIEGO CA


Personal Author(s) : Pappert,R A ; Shockey,L R


Full Text : https://apps.dtic.mil/dtic/tr/fulltext/u2/a061570.pdf


Report Date : 15 Aug 1978


Pagination or Media Count : 43


Abstract : A simple Kirchhoff-Huygens diffraction model has been used to estimate the effect of a patch of sporadic E on propagation in the lower ELF band. The patch is approximated by a lumped parameter phase-amplitude screen allowed to move along a great circle path normal to the transmitter-receiver great circle path. The results indicate that sporadic E patches on the order of 1000 x 1000 km, causing phase rate shifts and attenuation rate enhancements consistent with full wave modal evaluations, can account for the 6-8 dB fades observed in connection with 1600 km Wisconsin Test Facility (WTF) transmissions. The results suggest also that such disturbances can be expected to produce 2 to 4 dB fades over paths as long as 10,000 km. (Author)


Descriptors :   *IONOSPHERIC PROPAGATION , *EXTREMELY LOW FREQUENCY , RADIATION ATTENUATION , DIFFRACTION ANALYSIS , PHASE SHIFT , FRESNEL ZONES


Subject Categories : Atmospheric Physics
      Radiofrequency Wave Propagation


Distribution Statement : APPROVED FOR PUBLIC RELEASE