Indoor propagation prediction accuracy and speed versus number of reflections in image-based 3-D ray-tracing

Ray-tracing based prediction of indoor microwave propagation has great potential as a practical and accurate technique to engineer wireless systems. The prediction accuracy of such methods increases with the number of reflections included in a single propagation path. At the same time, the computation time grows exponentially with the number of reflections. Thus, it is critically important to understand the minimum number of reflections needed to achieve the desired level of accuracy. We quantify the prediction accuracy and computation time for a 3-D ray-tracing tool Wireless Systems Engineering Tool (WiSE) by comparing predictions to a large database of measurements collected in three different office buildings located in New Jersey, USA.