Impact of Building Materials on Wi-Fi Signal Propagation and Positioning Accuracy

Abstract

Indoor Positioning Systems (IPS) are essential for reliable navigation and location-based services inside buildings. However, construction materials introduce signal attenuation that reduces the accuracy of these systems. This study investigates the propagation of Wi-Fi signals through five different wall materials: concrete, drywall, glass, white-faced hardboard, and wood. The research introduces the Wall Attenuation Factor (WAF) to quantify signal loss and integrates it into Wi-Fi-based localization algorithms. Experimental results demonstrate that incorporating WAF significantly enhances positioning accuracy, reducing errors from 1–2.5 m to 20–50 cm. Coordinate accuracy improved from 0.5–6 m (X) and 1–4 m (Y) to 10–65 cm (X) and 20–30 cm (Y). Concrete walls caused the greatest signal attenuation, while wood and white-faced hardboard allowed signals to pass with minimal degradation. Optimal router placement, within 4 meters of the receiver and with proper alignment, further enhances performance. Future research will explore three-dimensional positioning and test the impact of environmental variables such as humidity and air density.