A comparative study of indoor propagation models for IEEE 802.11n network

Abstract

Indoor propagation models are considered as a mathematical expression to describe the wave propagation as a function of frequency, distance, and other conditions. Choosing the appropriate propagation model for a specific environment requires extensive analyses. The ray tracing 3D shoot-and-bounce ray (SBR) technique employed by Wireless InSite software is adopted in this work to simulate the signal propagation and evaluate its strength. Three indoor scenarios with two cases each; Line of sight (LOS) and non-line of sight (NLOS) are being simulated and tested. The test bed was conducted based on Net Spot software. The Basic objective is to compare the measured and simulated received power in order to introduce the potentials and limitations of using ray tracing to characterize the indoor wireless channel at 2.4 and 5 GHz. The comparison results show an acceptable correlation between experimental and simulation results. The effects of distance, frequency, and obstacles materialized by different furniture features have been investigated. The nodes that are located in LOS at room B outperforms the NLOS nodes which are located at room A by (3 dBm) in terms of mean received power for both frequencies. Long distance contributes significantly in signal strength reduction, where minimum received power equals to (-77 dBm) at 5 GHz is noticed at the corridor due to long distance. In addition, 2.4 GHz case verifies better signal quality due to less path loss, and the corridor scenario gains less difference between both frequencies. The office scenario achieves the minimum Mean Absolute Error (MAE) between experimental and simulation results at both 2.4 and 5 GHz.