Attenuation over distance and excess path loss for a large-area indoor commercial topology at 2.4 GHz

The present work features the evaluation of curve fitting models for the estimation of attenuation over distance and excess path loss, on the basis of extensive measurements performed in a large-area indoor commercial topology at 2.4 GHz. The case study is the departures level of Athens International Airport, including up to three Access Points. The basic propagation mechanisms in this scenario are free space propagation with direct Line-of-Sight, reflection and multipath. Hence, a shadow fading based methodology for the calculation of excess path loss and attenuation over distance is not applicable in this case. For this purpose, an alternate method has been developed, featuring various models which have been employed and fit to the experimental data. Their fitting robustness has been compared in terms of Goodness-of-Fit metrics such as the R-Square and the Adjusted R-Square. Coefficients with 95% confidence bounds have been calculated and put to the test. The excess path loss has been estimated in relation to the distance and the logarithm of the distance. Results vary as to their precision according to the nature of each case study, in terms of propagation mechanisms, and the efficiency of each curve fitting model.