Effects of terrain factors in 900 MHz GSM urban cells and a pathloss estimation approach

Increasing the capacity and coverage of cellular communication systems requires applying accurate propagation models which consider the influences of surrounding complicated environment on the transmitted signal. In this paper, the agreement of the measured values of received signal strength in 900 MHz band, with predicted data has been investigated and analyzed in an urban cell in Kermanshah, Iran. The results indicate that Hata-Okumura is the best prediction model for this region. Although the MSE for our narrowest path was about 2 dBs, for wider streets the MSE increased up to 10 dBs. We applied gradient descent algorithm to measured data to fit the model for our terrain. The modified model decreased the MSEs down to 2dBs for most of locations.