All SBR/image approach to indoor radio propagation modeling

Detailed understanding the radio propagation characteristics in a room will help the design of personal communication services (PCS) systems. There are two methods that have been applied to analyze this problem. The first, is the image theory, which is efficient, but can handle simple environments only. The second is the ray tracing technique, which is powerful for complex environments, but a reception sphere has to be introduced to determine the rays that reach the receivers, and the computed results are sensitive to the radius of the reception sphere. A deterministic model using a modified shooting and bouncing ray (SBR) technique is used to model the indoor radio propagation channels. This method can deal with complex environments, and the reception sphere is not needed. Conceptually we use the SBR method to trace ray tubes bouncing in the indoor environments. If the receiver is within a ray tube, the corresponding equivalent source (image) and its contribution to the received field at the receiver (Rx), can be determined. By summing all contributions, we can obtain the total received field at Rx.