Electromagnetic Field Assessment in Urban Zone with Hierarchic Description and  Homogeneisation Process



OP2H is a french project selected by the National Research Agency ANR (www.agence-nationale-recherche.fr).

The wireless systems are increasingly used in domestic environment. Last ten years, mobile  

Over the last decade the cell phone has experienced a great expansion with a number of GSM users rose from 200 in 1992 to over 40 million. Today it is the new broadband (WiFi, WiMax) and new wireless systems (ULB, wireless sensors), which develop significantly. These networks are very dense urban areas and the distribution of the electromagnetic field is very dependent on the structure of the city: density, form and nature of buildings.

To ensure sustainable mobility in conjunction with an optimum coverage and satisfy the constraints related to human exposure, these networks and their radiated power must take into account the constraints related to power consumption, the urban environment and that the fields generated by the antennas and access points.

To meet these multiple and sometimes contradictory, it is essential to have predictive tools to assess more accurately the radiated fields in order to allow an optimized implementation of antennas, to reduce to minimum the power radiated by those it and minimize the power consumed by the system.

The current generation of prediction tools (cover or exposure of people) do not take into account the local heterogeneities may induce large variations of the field. Indeed beyond the difficulties in information databases, methods consider buildings as homogeneous with the most openings. Hence radio resources are not always used with the greatest efficiency.

With new tools, taking into account the dynamic complexity of local scenes, the powers used and consumed could be reduced through better siting of antennas and reduced power output.