dc.description.abstract |
The free electron content of the Earth's ionosphere plays an important role in com
munication
and navigation systems. On the other hand, ionospheric electron density
irreguli1rities can
hamper communication technology applications through scintilla
tion (rapid
and random fluctuation in the amplitude and phase of signals) effects.
This suggests
the need for research into the prediction of the ionospheric variabil
ity
and the various phenomena that affect it. In this thesis, ground magnetometer
data of the geomagnetic field horizontal (H) intensity from a location (Addis Ababa:
9.02
o
N, 38.77
o
E geographic, magnetic dip O.l7oE, and Adigrat: 14.28°N, 39.46°E ge
ographic, magnetic dip 6
0
E) have been used to determine the EEJ strength at the
electrojet zone (Addis Ababa). Further, vertical
total electron content (vTEC) and
amplitude scintillation intensity (54) from a dual frequency GPS receiver which is
situated at Addis Ababa (within the electrojet zone) and functional under the inter
national SCINDA program of
the US Air Force have been utilized to examine the
time variations of (vTEC) and 54 in relation to the variations in the EEJ strength.
Relations between
the variables have been dictated through correlation analysis by
taking
peak values of EEJ on geomagnetically quiet days during August to November
2008. A negative or less correspondence between
EEJ and the variables 54 and vTEC
has been observed over the Ethiopian electrojet station, Addis Ababa. |
en_US |