Shooting-and-bouncing ray method for 3D indoor wireless propagation in WLAN applications

The paper presents a measurement based validation of a three-dimensional, "shooting-and-bouncing ray" (SBR) implementation of multi-bounce geometrical optics (GO) in a complex indoor environment for the 802.11b WLAN application. A transmitter was placed at a fixed interior location. A cart-mounted power meter was moved along several hallway routes on two floors to collect signals at regular intervals. A 3D CAD model of the building was developed for input to the propagation model, including interior wall detail. Material properties of the wall and floors were optimized to improve the comparison, but within reasonable constraints imposed by their known properties. Measurement routes were characterized for input to the model to predict densely sampled single levels along the same paths. The paper presents graphical and statistical comparisons of the measured signal levels and predictions of the 3D GO computer model. These comparisons show that the SBR propagation model performs very well in this highly complex scattering environment at 2.42 GHz. Background on the implemented model and its computational performance are also given.