Pramana

, Volume 55, Issue 5–6, pp 685–691 | Cite as

Matched filtering-parameter estimation method and analysis of whistlers recorded at Varanasi

  • R P Singh
  • R P Patel
  • Ashok K Singh
  • D Hamar
  • J Lichtenberger
Space And Astrophysical Plasmas Contributed Papers

Abstract

The matched filtering technique is based on the digital-construction of theoretical whistlers and their comparison with observed whistlers. The parameters estimated from the theoretical and experimental whistler curves are matched to have higher accuracy using digital filters. This yields a resolution ten times better in the time domain. We have tested the applicability of this technique for the analysis of whistlers recorded at Varanasi. It is found that the whistlers have propagated along L>2 and have wave normal angles after exiting from the ionosphere such that they propagate towards equator in the earth-ionosphere wave-guide. High-resolution analysis shows the presence of fine structures present in the dynamic spectrum. An effort is made to interpret the results.

Keywords

Matched filtering fine structure ducted mode propagation banded whistlers 

PACS No

94.30.Tz 
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Copyright information

© Indian Academy of Sciences 2000

Authors and Affiliations

  • R P Singh
    • 1
  • R P Patel
    • 1
  • Ashok K Singh
    • 1
  • D Hamar
    • 2
  • J Lichtenberger
    • 2
  1. 1.Atmospheric Research Laboratory, Physics DepartmentBanaras Hindu UniversityVaranasiIndia
  2. 2.Department of GeophysicsEotvos UniversityBudapestHungary

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