Providing uninterrupted positioning services while moving through heterogeneous environments equipped with wireless networks is a main issue. Recent telecommunication researches have been carried out on global mobile equipment detecting any type of wireless network, with a transparent handover. An efficient positioning system would study all the data from the environment networks to elaborate a geographical user position, without an additional infrastructure. In this paper, we expose the first part of an automatic positioning system: a real time simulation system studying the visibility of the user equipment, in its environment. It is based on a global algorithm for the detection of the equipment of heterogeneous networks. The main steps consider a 3D environment simulation, with different type of equipment, mobility models, and visibility approach.