Earth-prints repository, logo   DSpace

About DSpace Software
|earth-prints home page | roma library | bologna library | catania library | milano library | napoli library | palermo library
Please use this identifier to cite or link to this item:

Authors: Baskaradas, J. A.*
Bianchi, S.
Pietrella, M.*
Pezzopane, M.*
Sciacca, U.*
Zuccheretti, E.*
Title: Description of ionospheric disturbances observed by Vertical Ionospheric Sounding at 3 MHz
Title of journal: ANNALS OF GEOPHYSICS
Series/Report no.: 1/57 (2014)
Issue Date: 2014
DOI: 10.4401/ag-6345
Keywords: Fading fluctuation
Ionospheric irregularities
Multipath fading
Abstract: High Frequency radio waves reflected by the ionosphere can provide a relevant amount of information within the composite received signal. The ionosphere is indeed a frequency dispersive, bi-refractive, absorbing medium, in which multipath propagation occurs due to disturbance on a varied time-spatial scale. On the time-spatial level of Small Scale Disturbances (SSD) the ionosphere dynamics, detectable by Vertical Ionospheric Sounding (VIS), is mainly dependent on wrinkled layers acting as multi-reflectors. The present paper discusses different aspects of the effects of multipath fading suffered by the wave along the propagation path and potentially associated with SSD. To achieve these objectives, a VIS campaign at a fixed frequency of 3.0 MHz was conducted at the ionospheric observatory in Rome (Latitude 41.8 N; Longitude 12.5 E), by collecting a series of measurements of the power variations in received echo signals recorded between two consecutive ionograms whose sounding repetition rate was set to 15 min. The obtained results show that: 1) the fading suffered by the wave follows either a Rayleigh trend or a Nakagami-Rice trend, or a mix of them, the mixed case being the most frequent (about 65 % of the analysed cases); 2) the predominant periodicities characterizing the power variation are less than 25 s; such values are compatible with the small scale ionospheric disturbances; 3) for all the 24 hours of the day the ionospheric reflector is pretty stable and for time intervals of 10-30 s the periods of stability occur with a percentage of occurrence ranging between 55% and 95 %; for time intervals of 190- 210 s the periods of stability occur instead with a percentage of occurrence ranging between 5% and 54 %.
Appears in Collections:01.02.02. Dynamics
01.02.05. Wave propagation
01.02.04. Plasma Physics
01.02.06. Instruments and techniques
Papers Published / Papers in press

Files in This Item:

File Description SizeFormatVisibility
2014_AnnalsOfGeophysics_3MHz.pdffull text713.64 kBAdobe PDFView/Open

Items in DSpace are protected by copyright, with all rights reserved, unless otherwise indicated.

Share this record




Stumble it!



Valid XHTML 1.0! ICT Support, development & maintenance are provided by CINECA. Powered on DSpace Software. CINECA