A Short-Term Forecast Method of Maximum Usable Frequency for HF Communication

To further improve the quantitative forecasting ability of high-frequency (HF) communication frequency, we propose a maximum usable frequency (MUF) adaptive forecasting method. This method has four new features: 1) the Volterra filter is introduced to this method, which is easy to implement due to the simple structure; 2) this method can forecast M(3000)F2 based on past measurements without using any previous or forecast data of geomagnetic and solar activity parameters; 3) the spatial characteristics of the M(3000)F2 can be obtained by the improved reconstruction method based on geomagnetic coordinates (GMCs); and 4) the high prediction accuracy can be obtained by the training dataset on the 27th day (one solar rotation period). Through the statistical analysis of the measurements and predictions, the results show that the forecast values are in good agreement consistent with the measurement during the geomagnetic quiet or the disturbance periods. This method is proven to have good adaptability and usability and has a further performance improvement compared with International Telecommunication Union (ITU) and long-term forecast models. And the root-mean-square error (RMSE) of MUF forecasts decreased by 1.9 and 0.9 MHz on average, and the relative RMSE decreased by 12.6% and 2.9% on average.