A wall imperfection channel model for signal level prediction and its impact on smart antenna systems for indoor infrastructure WLAN

This paper presents a novel approach for the estimation of the local average signal level in an indoor environment based on a wall imperfection model. A ray-tracing tool based on the method of images with angular information, is first used to estimate the distribution of field strength (or coverage) in an arbitrary environment. The concept of spatial sampling is highlighted. The wall imperfection model is then introduced to study the sensitivity of the received signal level at an arbitrary location to imperfect wall positioning and electromagnetic material properties. An alternative approach to estimate the local mean signal level at a particular point is presented based on the wall imperfection model to reduce the computation time. The impact of the wall imperfection model on the patterns of a smart antenna system serving multiple users in an infrastructure WLAN is studied.