The influence of sunspot number on high frequency radio propagation
This paper aims to study the influence of sunspot number on High Frequency (HF) radio communications in Peninsular Malaysia for the years 2009 to 2011. Sunspots, which are a natural phenomenon that occurs due to magnetic activities on the Sun’s surface, can be counted using smoothed sunspot number (...
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| Main Authors: | , , , |
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| Format: | Conference or Workshop Item |
| Published: |
2014
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| Subjects: | |
| Online Access: | http://eprints.uthm.edu.my/6695/ http://eprints.uthm.edu.my/6695/1/The_Influence_of_Sunspot_Number.pdf |
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| Summary: | This paper aims to study the influence of sunspot
number on High Frequency (HF) radio communications in
Peninsular Malaysia for the years 2009 to 2011. Sunspots, which
are a natural phenomenon that occurs due to magnetic activities
on the Sun’s surface, can be counted using smoothed sunspot
number (SSN). HF signal propagates through the ionosphere
where the ionospheric properties have been ionized by flares and
prominences from sunspot number. This has significant effect on
the stability of the ionosphere, resulting in the frequencies that
can be used for HF communications to vary depending on the
time of day, season, year and the 11-year solar cycle. This study
was carried out during a period when the sunspot values rose
from a low level in 2009 to a much higher level in 2011, making it
suitable to observe the influence of sunspot number values on the
HF frequencies employed. Maximum Usable Frequency (MUF)
was determined based on HF transmission tests that were
conducted from April 2009 to September 2011. It was observed
that as the SSN values increase, the range of the operating HF
frequencies and the numbers of frequencies that can be used also
increase. This will, therefore, affect the median frequency that
can be used for daily and monthly HF communications |
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