Seasonal Variation of VLF Radio wave Signal Strength at 19.8 KHz Received at Khatav India (16o46ʹN, 75o53ʹE)

Open Access

Year : 2025 | Volume : 14 | Issue : 03 | Page : 1 9
    By

    C. T. More,

  • B. R.Vibhute,

  • M. C. More,

  1. Assistant Professor, Department of Physics, Miraj Mahavidyalaya, Miraj, Maharashtra, India
  2. Assistant Professor, Department of Physics, Miraj Mahavidyalaya, Miraj, Maharashtra, India
  3. Research Scholar, SID Monitoring Station, Khatav, Maharashtra, India

Abstract

This research is a detailed study of the seasonal behavior of the VLF field strength of the waves transmitted by VLF station NWC Australia (19.8 kHz). This research was carried out by using the VLF Field Strength Monitoring System located at Khatav, India (16°46ʹN, 75°53ʹE) during the period of August 2009 to July 2010. This study explores how the ionosphere and VLF radio waves react to the solar radiation. In this study, signal strength recording shows seasonal variation, which depends on the illumination of the propagation path by the sunlight. In this case, the signal strength is more stable during daytime and fluctuates during nighttime due to the presence and absence of the D-region during daytime and nighttime, respectively. Also, it is observed that the sunrise and sunset time varies seasonally throughout the whole year. It is observed that the ionosphere varies diurnally and seasonally depending on the amount of direct sunlight received at the top of the atmosphere. The height of the ionosphere is lower in summer and during the day, and electron densities are higher. With this, it was expected that SID strength might also vary by season.

Keywords: VLF, Monitoring System, Receiver Great Circle Path (TRGCP), EUMETSAT’s Meteosat-9 satellite, Radio Wave,

[This article belongs to Research & Reviews : Journal of Space Science & Technology ]

How to cite this article:
C. T. More, B. R.Vibhute, M. C. More. Seasonal Variation of VLF Radio wave Signal Strength at 19.8 KHz Received at Khatav India (16o46ʹN, 75o53ʹE). Research & Reviews : Journal of Space Science & Technology. 2025; 14(03):1-9.
How to cite this URL:
C. T. More, B. R.Vibhute, M. C. More. Seasonal Variation of VLF Radio wave Signal Strength at 19.8 KHz Received at Khatav India (16o46ʹN, 75o53ʹE). Research & Reviews : Journal of Space Science & Technology. 2025; 14(03):1-9. Available from: https://journals.stmjournals.com/rrjosst/article=2025/view=223611


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Regular Issue Open Access Original Research
Volume 14
Issue 03
Received 30/07/2025
Accepted 07/08/2025
Published 08/09/2025
Publication Time 40 Days
167

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