This thesis is about indoor radio propagation. We usually design our indoor wireless network not paying enough attention to determine our network boundaries, coverage. This way our network will become more vulnerable to outside attacks and it will interfere with other nearby wireless radio networks. This thesis provides models, which help determine our indoor wireless radio network boundaries with ease. The established models provide an estimate for rooms, main hall, corridors and of the walls that separate them. The models were set site-specific, at the Budapest University of Technology and Economics in building I, with a series of measurements. The finished indoor radio propagation model takes the distance and the frequency as parameters. It provided better results, than the available models at the date of this thesis’s creation. The finished indoor radio propagation model is so simple it contains the posibility to be used in other geographical locations than the Budapest University of Technology and Economics building I.