A simulation study of urban in-building cellular frequency reuse

This article describes a simulation methodology for accessing capacity of secondary indoor wireless systems that share spectrum with conventional outdoor cellular systems. The techniques described may be used to predict the capacity of the indoor system over a multiyear time window. The results for the channel capacity for indoor "parasitic" cellular systems in a 48-story office building are presented over a 6-year time window. The simulations illustrate that the capacity of the indoor system varies with time as well as with the height above ground. Parasitic indoor systems are assumed to operate with RF power levels low enough that they cause negligible interference to the outdoor cellular system, so this work concentrated on the interference to the indoor system caused by the outdoor cellular (macrocellular) network.