IS ELECTROMAGNETIC POLLUTION NECESSARY IN URBAN AREAS?
Francesco Boella,
Livio Giuliani
National Institute of Occupational Safety and Prevention, Venice - Italy
Since 2002, studies on various Italian cities and towns have been done to evaluate
the level of public exposure to electrical and magnetic fields and electromagnetic
radiation present in the ambient environment, particularly in homes. These studies
have applied different calculus models, to each city, according to size, level of urban
development, and population densities, found in each study location. The results
show that that the maximum EMF level is above 3 V/m, even if all the available
power, provided by all the antennas in the neighbourhood are employed. The most
recent study considered a new wireless telephony network system architecture, based
on consolidated technologies and in this study we deduced that the Italian legal
exposure-limit of 6 V/m can be reduced without affecting network deployment
effectiveness. The development of new networks, due to the introduction of new
technologies and standards, will cause, in the near future, an increase in
electromagnetic exposure levels. To minimize the potential health risks due to
chronic EMF exposure, we studied how the use of networks of radio microcells
connected by optoelectronic hubs to a net of optical fibres could substitute for the
conventional net
There are three mainly considerations that justify this approach:
1. Coverage is guaranteed by a minimum signal level in support of the service;
starting from the link budget (we consider the threshold, for downlink of UMTS,
GSM e DCS at 66, 69, 72 dB
keep the environmental level of the electric field low;
2. The use of microcells reduce power in the antenna needed for uplink connections
from the handy and avoid high EMF exposure to the individual user;
3. Indoor coverage can be made by bringing the signal over fibres, employing only
picocells for wireless home connections; thus, it is not necessary to spread the
signal from powerful antennas that are able to pass through the buildings to reach
users on the road; this alternative model would avoid much of the causes of
electromagnetic urban pollution.
At the request of the City of Venice we developed a study to compare the
environmental pollution due to a conventional use of co-location antennas BTSs by
three Italian providers, operating in GSM, DCS and UMTS, and the pollution caused
by a microcell based network able to produce the same coverage in the same
neighborhood in Venice. The environmental levels of the produced electric field
were compared using a software simulator employing the ray-tracing algorithm (Fig.
1 and 2). The results suggest that the choices made for wireless telephony signal
deployment in Italy during the 1990s needs to be reconsidered.
1st HELLENIC CONGRESS - THE EFFECTS OF ELECTROMAGNETIC RADIATION
Thessalonica, 24-25 May 2008
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