Ionospheric empirical model: Initial approach to MUF modeling in the Malaysian region

The F2-layer peak height, hmF2, is one of the most important parameters needed for HF radio frequency planning and spectrum management. Therefore, the ability to model and predict HF frequencies using hmF2 empirical model is of great use for radio frequency planning and operation. This study aimed to identify and evaluate ionospheric empirical model, i.e. hmF2 empirical model, to be utilized as the initial maximum usable frequency (MUF) model in the Malaysian region. Malaysia is located at the magnetic equator which has special features compared to the ionosphere over temperate region. Therefore, there is a need to find suitable MUF model for HF transmission. Bradley-Dudeney, Dudeney and ITU-R formula were calculated to gain the MUF values from the empirical model by using 2009 Kototabang ionospheric data. RMSE for the MUF test and models was calculated to determine the minimum error models. Based on the results of the monthly hourly median of MUF test and models for the year 2009, MUF values from the models were found to be higher compared to the MUF test especially in the afternoon and at night. This may be caused by propagation distance and difference of magnitude dip latitude between the testing area and the ionospheric parameters´ area of data collection. Then, based on RMSE, the Dudeney model was identified and selected as the initial MUF model because of the lower RMSE values. However, the Dudeney model needs to be modified to obtain a more accurate MUF model.