Towards a Performance Boundary in Calibrating Indoor Ray Tracing Models

This paper investigates the performance boundaries of a calibrated deterministic indoor channel model. From a propagation modeling point of view, this process allows to assess the weakness of ray tracing and sets the boundary conditions for a such modeling method. The principle of the deterministic model calibration used in this work focuses upon the estimation of optimal material parameters by means of a few pilot measurements and a simulated annealing method. This technique improves the accuracy of the prediction model for all measurement positions including those not considered by the calibration. The performance of the calibrated ray tracing model and the sensitivity of the calibration to the number of pilot measurements have been investigated. For this investigation, a measurement campaign has been conducted within an indoor office building at 2.45 GHz with 100 MHz bandwidth. Furthermore, the model performance has been compared to empirical indoor models.