| Summary: | Submitted by Automa??o e Estat?stica (sst@bczm.ufrn.br) on 2017-11-22T19:39:17Z
No. of bitstreams: 1
FredSizenandoRossiterPinheiro_TESE.pdf: 2936282 bytes, checksum: e043d67f2ec70c4303eadd2ce8383354 (MD5) === Approved for entry into archive by Arlan Eloi Leite Silva (eloihistoriador@yahoo.com.br) on 2017-11-22T23:29:37Z (GMT) No. of bitstreams: 1
FredSizenandoRossiterPinheiro_TESE.pdf: 2936282 bytes, checksum: e043d67f2ec70c4303eadd2ce8383354 (MD5) === Made available in DSpace on 2017-11-22T23:29:37Z (GMT). No. of bitstreams: 1
FredSizenandoRossiterPinheiro_TESE.pdf: 2936282 bytes, checksum: e043d67f2ec70c4303eadd2ce8383354 (MD5)
Previous issue date: 2015-12-17 === O surgimento da Telefonia Celular, a partir dos anos 1990, e a constru??o fren?tica
de torres nas cidades assustou a popula??o, levou a comunidade cient?fica mundial e
os ?rg?os de controle ambiental a dar maior aten??o ?s ondas eletromagn?ticas n?o
ionizantes. Um estado pobre como o Rio Grande do Norte evoluiu a quantidade de
celulares em opera??o de 340 mil no ano 2002 para 4,6 milh?es em 2014. No RN a
quantidade de linhas celulares supera a pr?pria popula??o, com uma densidade de
128,98 acessos para cada 100 habitantes. Natal, a capital do RN, com 850 mil
habitantes, j? possui 882 Esta??es R?dio Base dos Sistemas celulares em 167,26 km2
de ?rea urbana. O objetivo do presente trabalho ? fazer um diagn?stico sobre a
exposi??o ? radia??o eletromagn?tica n?o ionizante em toda ?rea urbana da Cidade.
A metodologia usada levou em conta medi??es de intensidade das radia??es feitas
em 160 diferentes pontos da cidade. As medi??es foram feitas na faixa de 88MHz a
2.400 MHz. Os servi?os de telecomunica??es avaliados na pesquisa foram: TV
(Broadcasting), R?dio FM (Broadcasting), Sistemas Celulares e WLAN (IEEE
802.11bg).Foram considerados para compara??o os limites de exposi??o do ICNIRP
(InternationalCommission on Non IonizationProtection), par?metros: ?Intensidade de
Campo El?trico? e ?Raz?o de Exposi??o? (ER). Resultados: de acordo com as
medi??es realizadas, 48.48 % da exposi??o eletromagn?tica outdoor na cidade do
Natal decorre da radia??o emitida pelos transmissores de TV. Da mesma forma,
constatou-se que, em 77,2 % dos pontos pesquisados, a intensidade do campo
el?trico gerada pelas TVs supera todos os demais servi?os de telecomunica??es,
inclusive a Telefonia Celular. A Taxa de Exposi??o (ER) m?dia de Radia??o N?o
Ionizante verificada para a faixa de frequ?ncia pesquisada foi de 4,43. 10 -3, enquanto
o valor m?ximo foi de 7,67. 10-2. Foi desenvolvido modelo para estimativa do Campo
El?trico gerado pelos transmissores das TVs em qualquer ponto da cidade. Utilizouse
a T?cnica Estat?stica de Regress?o Multivariada, a partir das 160 amostras. As
equa??es finais obtidas permitem as estimativas com grau de precis?o R2 superior a
0,9, p<0,1. Constatou-se que o expoente de atenua??o para propaga??o de RF na
cidade varia entre 2,8 e 3,8. A exposi??o eletromagn?tica ? RNI em ambientes outdoor
em Natal est? em n?veis abaixo dos limites de seguran?a definidos pelo ICNIRP e
ANATEL. Os servi?os que mais contribuem para RNI em Natal s?o: 1-TV, 2-Sistema
Celular e 3-R?dios FMs. === The electromagnetic waves used in the telecommunication systems until the 1980?s
were considered by the governments environmental control organs as apparently
?clean? forms of energy, whose effects weren?t considered any harmful to people?s
health. The development of the mobile cellular telecommunication, beginning in the
1990?s, and the frenetic construction of antennas in the cities? urban areas scared the
population in general and turned the attention of the world?s scientific community to the
theme. In a poor Brazilian State, such as Rio Grande do Norte ? RN (GDP:R$ 51,4
billion in 2013) , the amount of cellular phones in operation went from 340.000 in 2002
to 4.6 million phones in 2014. In RN the number of cellular lines overcomes its own
population, with a density of 128.98 accesses for each 100 inhabitants. Natal, the
capital city of the State, with 850.000 inhabitants, already has 885 radio base stations
of the cellular systems in 167.26 km? of urban area. The data is from ANATEL (august
2015). The objective of this work is to make a diagnosis about the actual situation of
the emission of non-ionizing electromagnetic radiation in all urban area of the city of
Natal. The methodology used took into account measurements of the intensity of the
radiation taken in 160 different sites throughout the city. This radiation was measured
in the range of 88MHz to 2.400 MHz. The collected data was compared to the limits of
exposure of the ICNIRP (International Commission on Non Ionization Protection). The
ICNIRP parameters used as reference were: ?intensity of electric field? and ?exposure
ratio?. The telecommunication services researched were: TV broadcasting, FM radio
broadcasting, cellular systems and WLAN (IEE 802.11bg). The obtained results
allowed the drawing of a map comparing the data between the measured values and
the limits of exposure to RNI defined by ICNIRP and ANATEL. The evaluation criteria
used was the parameters Intensity of Electric Field and Exposure Ratio (ER). Results:
according to the measurements taken, 48.48% of the outdoor electromagnetic
exposure in the municipality of Natal are originated from TV transmitters. Similarly, in
77.2% of the researched locations, the intensity of the electric field originated from TVs
overcomes all the rest of the wireless telecommunication services, including the
cellular system. Based on the information that the radiation emitted by the TV
transmitters is the most relevant in the city, a model to estimate the intensity of the
electric field resulting from this service in any point in town was developed. This model
was developed based on multivariate regression techniques. The final equations obtained allowed the estimative of the electric field with a level of precision R2> 0,9
and p<0,1. It was found that the exponent RF propagation attenuation in Natal varies
between 2.6 and 2.8.The average Exposure Rate (ER) to NIR observed in the
researched frequency rate was of 4.43.10-3, while the maximum value was of 7.67. 10-
Conclusions: The results of the study demonstrated that the levels of electromagnetic
exposure to NIR in outdoor environments in the city of Natal are lower than the security
limits set by ICNIRP and ANATEL. The services that contribute most to NIR in Natal
are 1-TV, 2- Cellular System and 3-FM Radios.
|
|---|
