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Procedures for the long-term prediction of performance of terrestrial HF systems have been based on the prediction of monthly median conditions, with the subsequent application of statistical distributions, or geophysical or solar parameters, for other time percentages. However, there may be little correlation with time or location of ionospheric variability for various ionospheric parameters. The...
ITU-R Recommendations and the international agreements for HF broadcasting have specified the minimum usable field strengths to achieve a satisfactory quality of service. Other telecommunication systems, such as power line telecommunication, also use the same frequency ranges for their networks and may give rise to increased background noise levels for broadcasting due to unwanted emissions from such...
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