Optimization of Hata Pathloss Model Using Terrain Roughness Parameter

In this paper, an approach for optimizing Hata pathloss model based on terrain roughness parameter is presented. The study is based on field measurement of received signal strength and elevation profile obtained in a suburban area for a GSM network in the 800 MHz frequency band. Mostly, standard deviation of elevation is used to characterize terrain roughness. However, in this paper, the mean elevation and the standard deviation of elevation are used separately to minimize the error using least square method. The results show that the untuned Hata model has a RMSE of 44.58 dB and prediction accuracy of 65.07%. On the other hand, both the pathloss predicted by the mean elevation tuned Hata model and the pathloss predicted by the standard deviation of elevation tuned Hata model have the same RME of 6.23 dB and prediction accuracy of 96.06%. Also, the terrain roughness correction factors are the same value (that is, C TSDV=C TMean=44.13848). Finally, with the RMSE of about 6 dB, it can be concluded that the terrain roughness parameter-based tuning approach can effectively be used to minimize the prediction error of the Hata model within the acceptable value which is about 7dB to 10 dB for urban and rural areas.