Title :
Ionospheric mapping for HF communications and HF direction finding
Author :
Cilliers, P.J. ; Coetzee, P.J. ; Olckers, J.
Author_Institution :
Hermanus Magnetic Obs.
Abstract :
High frequency (HF, 3-30 MHz) radio communications are still extremely popular in Africa. However, HF is also widely used by illegal broadcasters and criminal elements including drug traffickers. This in turn has created a continued demand for HF direction finding (HF-DF). This paper presents the current status of the various means available for ionospheric mapping in Southern Africa and its applications in HF radio communications and direction finding. The operation, merits and limitations of the following methods of ionospheric mapping are addressed: the statistical international reference ionosphere (IRI) model; ionograms as derived from the three digisonde radar stations in South Africa; and computerised ionospheric tomography (CIT) based on total electron content (TEC) in the ionosphere, derived from the signals received by the network of dual frequency GPS receivers in Southern Africa
Keywords :
Global Positioning System; HF radio propagation; computerised tomography; ionospheric electromagnetic wave propagation; ionospheric measuring apparatus; radio direction-finding; 3 to 30 MHz; CIT; HF direction finding; HF-DF; IRI model; computerised ionospheric tomography; digisonde radar stations; dual frequency GPS receivers; high frequency radio communications; ionograms; ionosphere total electron content; ionospheric TEC; ionospheric mapping; statistical international reference ionosphere model; Africa; Application software; Computer networks; Drugs; Frequency; Ionosphere; Radar; Radio broadcasting; Radio communication; Signal mapping;
Conference_Titel :
AFRICON, 2004. 7th AFRICON Conference in Africa
Conference_Location :
Gaborone
Print_ISBN :
0-7803-8605-1
DOI :
10.1109/AFRICON.2004.1406650
