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Title: Characterization of Scintillation Events With Basis on L1 Transmissions From Geostationary SBAS Satellites
Abstract Signals recorded by two stations in the Brazilian region: [Fortaleza (3.74°S, 38.57°W) and Inconfidentes (22.31°S, 46.32°W)], receiving L1 transmissions from different geostationary satellites, were used to evaluate the amplitude scintillation indexS4and several characteristics of scintillation events (continuous record withS4 > 0.2) during nighttime hours (18:00 LT–02:00 LT) in the years 2014–2016. The effects from solar activity, season, and local time on the number of scintillation events per night, maximum scintillation, scintillation event duration, and spacing between consecutive events will be discussed. The results indicate that: (a) scintillation occurs from September to March in both links; (b) the most likely numbers of observed scintillation events per night were two or three, particularly during the first 2 years; (c) on average, the first scintillation event usually had larger maximumS4values when compared to those of the later ones along the night; (d) the first scintillation event had a longer mean duration than the succeeding ones in a given night; (e) the durations of scintillation events, regardless of their numbers per night and the location, decreased with local time; (f) the opposite dependence of spacings between consecutive events on local time was observed; (g) the cumulative distribution functions of the scintillation onset time indicated a strong dependence on the dip latitude of the station; and (h) early occurrences of onset times are directly related to the increased probability of the occurrence of multiple scintillation events.  more » « less
Award ID(s):
2122639 1916055
PAR ID:
10521475
Author(s) / Creator(s):
; ; ; ; ;
Publisher / Repository:
AGU
Date Published:
Journal Name:
Space Weather
Volume:
22
Issue:
1
ISSN:
1542-7390
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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