Path Loss Prediction Model for GSM Fixed Wireless Access

Abstract

This research investigated the effect of building materials on GSM signals quality. Measurements were conducted on MTN, Glo, Airtel and Etisalat networks using Radio Frequency Signal Tracker on six different building patterns. The results showed that building with alucoboard wall cladding had the highest signal loss while the sandcrete building/unrusted corrugated iron sheet roof had the least signal loss. Also, a model to predict signal penetration through building walls was developed. It was developed using the principles of Fresnel Refraction Coefficient and the knife-edge diffraction. The total losses from the transmitter to the receiver was modelled as a combination of three different effects; losses due to free-space propagation from transmitter to building; the penetration loss was modelled as a combination of the wall penetration loss and the diffraction loss. The results show that despite the condition of the building walls, movement of people in the environment/room also affected the wireless signal quality as well as the chairs and gadgets in the room. The indoor signal path loss in the rooms increased from when the walls were plastered and continued until when the walls were covered with curtains, both rooms reduced by 4dBm. The mean squared error ranged between 1.6dBm and 2.1dBm with a standard deviation between 11.1 and 11.5.