Observations of Doppler and delay spreads on HF signals received over polar cap and trough paths at various stages of the solar cycle
Article first published online: 24 OCT 2013
©2013 The Authors. Radio Science published by Wiley on behalf of the American Geophysical Union.
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Volume 48, Issue 5, pages 638–645, September-October 2013
How to Cite
2013), Observations of Doppler and delay spreads on HF signals received over polar cap and trough paths at various stages of the solar cycle, Radio Sci., 48, 638–645, doi:10.1002/2013RS005264., , and (
- Issue published online: 15 NOV 2013
- Article first published online: 24 OCT 2013
- Accepted manuscript online: 8 OCT 2013 04:27PM EST
- Manuscript Accepted: 4 OCT 2013
- Manuscript Revised: 23 SEP 2013
- Manuscript Received: 9 JUL 2013
- EPSRC. Grant Numbers: GR/N16877/01, GR/N66056/01, EP/C014642/1
- HF propagation;
- midlatitude trough;
- polar cap ionosphere;
- channel dispersion
 Information on delay and Doppler spreading is of importance to designers and operators of digital communication systems within the HF band since modem performance rapidly deteriorates when delay and Doppler spreads exceed system dependent thresholds. The northerly ionosphere is a particularly challenging region in this regard as delay and Doppler spreads often significantly exceed those for similar length paths at midlatitudes. This paper presents results from an extensive set of measurements undertaken over three northerly paths: two subauroral paths aligned along the midlatitude trough (Uppsala to Bruntingthorpe and Nurmijärvi to Bruntingthorpe) and one path (Qaanaaq to Ny-Ålesund) contained entirely within the polar cap. Measurements span the period from the 2009 solar minimum to July 2012, close to solar maximum and 2001, close to the previous solar maximum.