This paper intends to study outdoor RF attenuation path loss behavior under certain restrictions. The study has been conducted in Nablus city to develop and optimize a suitable propagation model based on one of the existing propagation models based on outdoor measurements for 900 MHz, where a local GSM system is operating under sever geographical terrains and frequency limitations. The optimized model has been chosen such that certain error parameters are minimized. Some of the proposed models are; Bertoni-Walfish, Hat, Walfisch-Ikegami and the standard macrocell. In this paper a Tuned Bertoni-Walfisch model has outperformed the other models and has proven, to be the best suited for propagation analysis involving such terrain. This is achieved by varying the range dependence using Least Mean Square Error

Mobile communications has become an everyday commodity. In the last decades, it has evolved from being an expensive technology for a few selected individuals to today’s ubiquitous systems used by a majority of the world’s population. Imprecise propagation models lead to networks with high co-channel interference, as well as power waste. This study aims to adapt a propagation model in the city of Nablus (Palestine) for a GSM frequency band. This study helps to design better GSM networks for the city in spite of the geographical and frequency limitations. The modification is accomplished by investigating the variation in path loss between the measured and predicted values, according to the propagation model for a specific cell. The results from a simulation model and measured data was compared and analyzed. Bertoni-Walfisch model, without tuning, gave the best results with a mean error of 1.426 dB, which is much less than the mean error obtained by the Standard Macrocell model, 10.91 dB, which is used by a local mobile operator. The two models have been tuned to fit measured data for GSM-900 in the city of Nablus. This is a vital step in cell planning and rollout of wireless networks. To confirm the superiority of Bertoni-Walfisch, a comparison between Bertoni-Walfisch and Standard Macrocell model in terms of Standard Deviation and Mean Error (RMSE).