Please use this identifier to cite or link to this item:
|Authors: ||Bianchi, C.*|
Baskaradas, J. A.*
|Title: ||Fading in the HF ionospheric channel and the role of irregularities|
|Title of journal: ||Advances in space research|
|Series/Report no.: ||3/52(2013)|
|Publisher: ||Elsevier Science Limited|
|Issue Date: ||11-Apr-2013|
|Keywords: ||Fading fluctuation;|
Multipath time-variant channel
|Abstract: ||It is well known that the ionosphere affects radio wave propagation especially in the high frequency (HF) range. HF radio waves
reflected by the ionosphere can reach considerable distances, often with changes in amplitude, phase, and frequency. The ionosphere is a dispersive in frequency and time, bi-refractive, absorbing medium, in which multipath propagation due to traveling irregularities is very frequent. The traveling irregularities undulate the reflecting ionospheric layer, introducing variations in signal amplitude (fading).
In this multipath time variant channel fading is mainly considered, even though it is not the sole effect. Echo signals from a single reflection, as in ionospheric vertical sounding (VIS) techniques, are affected by a certain degree of variability even in quiet ionospheric conditions.
In this work the behavior of the ionospheric channel is studied and characterized by observing the power variation of received
echoes using the VIS technique. Multipath fading was analyzed quantifying the power variation of the signal echo due to irregularities on a temporal scale from 0.5 to 256 s. An experimental set-up derived from an ionosonde was implemented and the analysis was performed employing a special numerical algorithm operating off-line on the acquired time sequence of the signal. The gain-loss of the irregularity shapes are determined in some special cases.|
|Appears in Collections:||01.02.02. Dynamics|
01.02.99. General or miscellaneous
01.02.05. Wave propagation
01.02.06. Instruments and techniques
Papers Published / Papers in press
Files in This Item:
|published.pdf||full_article||1.28 MB||Adobe PDF||only authorized users
Items in DSpace are protected by copyright, with all rights reserved, unless otherwise indicated.