Investigating propagation curves of electric field intensity of Jigawa Medium Frequency Radio Transmitter
This study investigates the variations in the electric field intensity of Jigawa Medium Frequency (MF) radio signal along some radio routes using propagation curve. It also compares the propagation curves due to measured field intensity with those predicted by GRWAVE software using the ground electrical conductivity of the routes. The need to predict propagation curves using GRWAVE software and compare same with empirical curves to ascertain the adequacy and suitability of the predicted curves to characterize MF propagation in Northern Nigeria is the motivation for this study. Electric field intensity data were acquired with the aid of Potomac electric field intensity meter and a Garmin 38Global Position System (GPS) receiver registered both coordinates and elevations along the routes. Theoretical equation was used to deduce the values of ground electrical conductivity from the measured field intensity and the values were used along with the transmitter configuration in GRWAVE software to compute the predicted field intensity. Results reveal experimental propagation curves are fairly higher compared to predicted curves. At 30 km from the transmitter, the values of measured and predicted electric field strength are 1.30 and 1.06 mV/m along Tundun Wada route, 1.50 and 1.11 mV/m along Azare route, 1.40 and 1.15 mV/m along Kefin Hausa route, 1.41 and 1.13 mV/m along Kogin Maikaho route, 1.26 and 1.03 mV/m along Kundun route, 1.50 and 1.11 mV/m along Fulani route, and 1.25 and 1.11 mV/m along Dutse Kan route. Therefore GRWAVE software can be used to predict propagation curves suitable for MF propagation in Northern Nigeria using the ground electrical conductivity of the terrain.
Key word: Propagation curve, electric field intensity, ground electrical conductivity, ground wave.