Determination of Pathloss Exponent 4G LTE Signal in Urban and Rural Environment of Southern Nigeria (Asaba in Delta State and Onitsha in Anambra State)

We investigated the radio frequency channel behavior based on extensive measurements of signal strength and other propagation parameters up to 1200 m from the base stations, adopting single sector verification technique in wet and dry season in urban and rural environments of Delta and Anambra States in Nigeria. The measurements were carried out at 800 MHz bands using Sony Ericson Test Mobile System (TEMS) phones and global positioning system connected to a laptop equipped with TEMS software and cell refs of the base stations in the studied areas. The estimated pathloss values were compared with four commonly used propagation models namely: Erceg, Cost-231, Ericson, and Standard University Interim (SUI). SUI model presented a better agreement with the measured pathloss based on root mean square error (RMSE) metrics analysis in all the considered environments in both seasons. Modification of the SUI model was carried out by including the pathloss exponent which performed better in predicting the pathloss compared with commonly used SUI propagation models. Climatological parameters such as pressure, temperature and relative humidity at ground surface over all the monitored environments were obtained between 2022 and 2023. These data were used to compute the refractivity gradient, effective earth radius (k-factor), and geoclimatic factor for the studied area. Results show that using the standard value of 1.33 for k-factor in the investigated environments, the required height of antenna for line-of-sight communication link setup may not be achieved. This may result in overestimation or underestimation of the required link budget needed for urban and rural environments in southern Nigeria environment.