Результаты исследований: Научные публикации в периодических изданиях › статья › Рецензирование
Time of flight and direction of arrival of HF radio signals received over a path along the midlatitude trough : Theoretical considerations. / Siddle, D. R.; Zaalov, N. Y.; Stocker, A. J.; Warrington, E. M.
в: Radio Science, Том 39, № 4, 01.07.2004.Результаты исследований: Научные публикации в периодических изданиях › статья › Рецензирование
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TY - JOUR
T1 - Time of flight and direction of arrival of HF radio signals received over a path along the midlatitude trough
T2 - Theoretical considerations
AU - Siddle, D. R.
AU - Zaalov, N. Y.
AU - Stocker, A. J.
AU - Warrington, E. M.
PY - 2004/7/1
Y1 - 2004/7/1
N2 - Observations from an HF radio experiment on a subauroral path between Sweden and the UK near sunspot maximum in 2001 are compared with the position of the midlatitude trough according to a statistical model. Periods of off-great circle propagation, occurring predominantly in winter and equinoctial nights at frequencies 7-11 MHz, show characteristics consistent with scattering from field-aligned irregularities in the northern trough wall and/or auroral oval. Very little reflection and/or scattering was apparent from directions to the south of the great circle path. These results are in marked contrast with those from a similar experiment conducted near sunspot minimum in 1994 in Canada, during which both southerly and northerly deviations were observed in the 5-15 MHz range. The contrasting results were simulated using ray tracing through a model ionosphere incorporating a model of the trough and, optionally, precipitation. The observed off-great circle propagation features on the European path could only be reproduced when precipitation within the northern trough wall/auroral zone was included, whereas features of the northerly and southerly deviations observed in the Canadian experiment could be simulated by the presence of the trough walls and without the need for precipitation.
AB - Observations from an HF radio experiment on a subauroral path between Sweden and the UK near sunspot maximum in 2001 are compared with the position of the midlatitude trough according to a statistical model. Periods of off-great circle propagation, occurring predominantly in winter and equinoctial nights at frequencies 7-11 MHz, show characteristics consistent with scattering from field-aligned irregularities in the northern trough wall and/or auroral oval. Very little reflection and/or scattering was apparent from directions to the south of the great circle path. These results are in marked contrast with those from a similar experiment conducted near sunspot minimum in 1994 in Canada, during which both southerly and northerly deviations were observed in the 5-15 MHz range. The contrasting results were simulated using ray tracing through a model ionosphere incorporating a model of the trough and, optionally, precipitation. The observed off-great circle propagation features on the European path could only be reproduced when precipitation within the northern trough wall/auroral zone was included, whereas features of the northerly and southerly deviations observed in the Canadian experiment could be simulated by the presence of the trough walls and without the need for precipitation.
KW - Ionospheric HF propagation
KW - Midlatitude trough
UR - http://www.scopus.com/inward/record.url?scp=5444246146&partnerID=8YFLogxK
U2 - 10.1029/2004RS003052
DO - 10.1029/2004RS003052
M3 - Article
AN - SCOPUS:5444246146
VL - 39
JO - Radio Science
JF - Radio Science
SN - 0048-6604
IS - 4
ER -
ID: 36552586