Earth, Planets and Space

, Volume 57, Issue 1, pp 47–59 | Cite as

Spectral characteristics of scintillations producing ionospheric irregularities in the Indian region

  • S. Banola
  • B. M. Pathan
  • D. R. K. Rao
  • H. Chandra
Open Access


VHF amplitude scintillations were recorded at Tirunelveli (8.7°N, 77.7°E; 0.6°N dip Latitude), Pondicherry (12°N, 79.1°E; 4.4°N dip Latitude) and Mumbai, (19°N, 73°E; 13.5°N dip Latitude) for the years 1992–1996 using the 250 MHz radio beacon from the geostationary satellite FLEETSAT (73°E). The recorded digital scintillation data for few nights are analyzed to estimate scintillation index (S4), fade rates, auto-correlation functions and power spectral densities for every 2.5 minute sample during the period of the scintillation activity. The power spectral slopes are shallower for the scintillation at the generation phase and steeper towards the decay phase, which indicates the erosion of smaller scale sizes towards the decay phase.

Key words

Equatorial ionosphere ionospheric irregularities VHF Scintillation fade rate 


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Copyright information

© The Society of Geomagnetism and Earth, Planetary and Space Sciences (SGEPSS); The Seismological Society of Japan; The Volcanological Society of Japan; The Geodetic Society of Japan; The Japanese Society for Planetary Sciences. 2005

Authors and Affiliations

  • S. Banola
    • 1
  • B. M. Pathan
    • 1
  • D. R. K. Rao
    • 1
  • H. Chandra
    • 2
  1. 1.IndiNavi MumbaiIndia
  2. 2.Physical Research LaboratoryNavrangpura, AhmedabadIndia

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