Comparative Analysis and Optimization of Okumura-Hata and COST 231 Propagation Models with Field Measurements in Sokoto Metropolis, Nigeria

Accurate path loss prediction is critical for efficient GSM network planning. This study evaluates the performance of Okumura-Hata, and COST 231 models against field-measurements for Airtel and 9mobile in Sokoto Metropolis, Nigeria. Field data were collected using a Gionee S9 smartphone with installed Network Cell Info Lite, GPS tools, and a cell tower locator app, across urban-suburban routes, and models were optimized with terrain specific clutter factors. Results show the modified COST 231 model (with a clutter factor of 1.8 dB/Km) achieved the lowest prediction errors, reducing RMSE to 4.0 dB for Airtel and 3.6 dB for 9mobile, outperforming the standard models by 35- 42%. The study concludes that model localization is essential for optimal GSM deployment in Sokoto’s urban-suburban environment