Robust HF data communisations at high latitudes

Citation
Tj. Willink et al., Robust HF data communisations at high latitudes, IEE P-MIC A, 146(4), 1999, pp. 263-269
Citations number
12
Categorie Soggetti
Eletrical & Eletronics Engineeing
Journal title
IEE PROCEEDINGS-MICROWAVES ANTENNAS AND PROPAGATION
ISSN journal
13502417 → ACNP
Volume
146
Issue
4
Year of publication
1999
Pages
263 - 269
Database
ISI
SICI code
1350-2417(199908)146:4<263:RHDCAH>2.0.ZU;2-G
Abstract
It is well known that the ionosphere can be highly disturbed in the auroral and polar cap regions. However, efforts to quantify ionospheric effects on high-frequency communications have concentrated mainly on lower-latitude r egions. The Doppler and multipath sounding network (DAMSON) has been used i n an extensive campaign to measure the channel characteristics on four path s in the auroral region of northern Scandinavia. The conditions observed in dicate that robust data modems, used when less-robust, higher-rate modems f ail, are required up to 90% of the time. A detailed analysis of the propaga tion parameters indicates that these modems, designed to operate in these r egions, should be able to operate when the Doppler spread exceeds 40Hz and the multipath spread is greater than 11.5ms. Multiple propagation modes are common, especially between the lowest and maximum usable frequencies. The distribution of the received signal power in these cases is examined, and i t is concluded that laboratory simulations used for robust-modem evaluation should include channel models with dominant modes.