Improving FoF2 Prediction for the Sunrise Transition Period

Improving FoF2 Prediction for the Sunrise Transition Period

Author: B. S. Dandekar

Publisher:

Published: 1986

Total Pages: 68

ISBN-13:

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During the 2- to 3-hr sunrise transition period, the relative change in foF2 is 20-60 percent per hour and is independent of solar activity. The change is largest in winter and smallest in summer. To prevent the skip distance from changing by more than 250 km, that is, to maintain continuous illumination of at least 50 percent of the barrier (nominal width 500 km), requires that the operating frequency be changed for every 6 percent change in foF2. Thus, in the case of an OTH system, the operating frequency has to be adjusted during the sunrise period every 6 to 20 min (seasonal dependence) for satisfactory performance. To accommodate such rapid changes, an empirical algorithm has been tested for improved foF2 predictions during sunrise. The prediction scheme is based on the availability of relevant (under the oblique raypath) real time ionospheric data.


Ionospheric Prediction and Forecasting

Ionospheric Prediction and Forecasting

Author: Bruno Zolesi

Publisher: Springer Science & Business Media

Published: 2013-09-25

Total Pages: 244

ISBN-13: 3642384307

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This book describes how to predict and forecast the state of planet Earth’s ionosphere under quiet and disturbed conditions in terms of dynamical processes in the weakly ionized plasma media of the upper atmosphere and their relation to available modern measurements and modelling techniques. It explains the close relationship between the state of the media and the radio wave propagation conditions via this media. The prediction and forecasting algorithms, methods and models are oriented towards providing a practical approach to ionospherically dependent systems design and engineering. Proper understanding of the ionosphere is of fundamental practical importance because it is an essential part of telecommunication and navigation systems that use the ionosphere to function or would function much better in its nonappearance on the Earth and on any planet with an atmosphere.