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: http://hdl.handle.net/2122/8978

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
Ionograms
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
Del.icio.us

Citeulike

Connotea

Facebook

Stumble it!

reddit


 

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