Abstract:In this paper, Hacking rounded edge diffraction loss method is used to determine the diffraction loss over a plateau in the path of microwave signal in the GSM frequency band, 800 MHz to 2100 MHz. The computation is based on the path profile with path length of 4996.243 m and a plateau in the signal path. The plateau has maximum elevation of 268.9 m and it occurred at a distance of 3557.8 m from the transmitter. The line of sight clearance height is 45.747499 m and occultation distance is 1538.759 m. At 800 MHz, the diffraction loss is 55.25 dB whereas at 2100 MHz the diffraction loss is 71.713 dB. The result is useful for GSM network planning.