This document summarizes a study on the radiation from mobile phone towers. It discusses the radiation patterns of tower antennas and how power density decreases with distance from the tower. It also addresses the theoretical and measured radiation levels, compliance distances recommended by international standards, and the biological effects of tower radiation on humans and the environment. While mobile companies deny health risks, the document concludes that long-term exposure can pose serious health hazards and stricter radiation norms should be enforced globally.

1. STUDY OF RADIOACTIVITY DUE TO BAND
SIGNALS FROM MOBILE TOWER
SEMINAR CO-ORDINATOR
ANIL JAYAMOHAN
RENJITH A
PRESENTING BY
MUNEESH NK
REG.NO 19123419
DATED ON 24-09-2014
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2.  INTRODUCTION
 RADIATION FROM CELL TOWERS
 MOBILE PHONE TOWER
 RADIATION
 RADIATION PATTERN OF THE ANTENNA
 POWER DENSITY AND RADIATION LEVEL
 THEORETICAL AND MEASURED RADIATED
POWER
 RADIATION MEASUREMENT DEVICE
 REALIZATION OF COMPLIANCE DISTANCE
 RADIATION SHIELD
 BIOLOGICAL EFFECTS OF CELL TOWER
RADIATION ON HUMAN BODY
 CASE STUDY
 RADIATION NORMS ADOPTED IN INDIA AND
OTHER COUNTRIES
 CONCLUSION
CONTENTS
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3. INTRODUCTION
 As Cell phone technology has revolutionized , Large
number of BTSs/towers is deployed
More than 50 crore cell phone users and nearly 4.4
lakh cell phone towers in India
 Study of cell tower radiation is essential in daily life.
 Presence of large number of antennas on single tower
with multiple carriers
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4. Radiation from cell towers
 Antennas on Cell tower transmit in the
frequency range of:
869 - 890 MHz (CDMA)
935 - 960 MHz (GSM900)
1805 – 1880 MHz (GSM1800)
2110 – 2170 MHz (3G)*
 Cell towers transmit radiation 24x7Mobile
 People living within 100’s of meters from the tower will
receive 10,000 to 10,000,000 times stronger signal than
required for mobile communication.
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5. Mobile phone tower
 Mobile tower have electronic
equipment and antennas.
 They receive and transmit
radiofrequency (RF) signals.
 The antennas need to be high
enough , so they can adequately
cover the area.
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6.  phone operators divide a region in large number
of cells, and each cell is divided into number of
sectors
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7. RADIATION
 Radiation is a form of energy on the move.
 Radiation is electromagnetic in nature
 There are two types of radiation:
1. Ionizing radiation
2. Non-ionizing radiation (NIR)
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8. RADIATION PATTERN OF THE
ANTENNA
 The radiation pattern of a cell tower antenna is defined
by its lobes.
 Radiation will be highest from the primary lobes in the
horizontal direction.
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10. Radiation Pattern of Antenna
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11. POWER DENSITY AND RADIATION
LEVEL
 The power density at any distance from an isotropic antenna
is the transmitter power divided by the surface area of a
sphere at that distance.
 The surface area of the sphere increases by the square of the
radius.
Equation
S = PG/4R2
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12. Radio Frequency
Range
General Public
Exposure
General Public
Exposure
1 to 10 MHz r = 0.10 √eirp×f r = 0.129√erp×f
10 to 400 MHz r = 0.319 √eirp r = 0.409 √erp
400 to 2000MHz r = 6.38 √eirp/f r = 8.16 √erp/f
2000 to 300000MHz r = 0.143 √eirp/f r = 0.184
Compliance distance recommended by ICNIRP
(based on ITU K.70 fact sheet formula)
√erp/f
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13. GSM cell tower power density levels –
percentiles
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14. Theoretical and measured radiated power
 To measure the power at a distance R from the transmitting cell
tower antenna,
 Equation
 At 887 MHz (tower transmitting frequency in CDMA), Pr = -3.2 dBm.
 At 945 MHz (tower transmitting frequency in GSM900), Pr = -3.8 dBm.
 At 1872 MHz (tower transmitting frequency in GSM1800), Pr = -9.7 dBm
 Power density for all these frequencies is 31,800 μW/m2. 10/24/201
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15. 10/24/201
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RADIATION MEASUREMENT DEVICE
Measurement of received power using
dipole antenna and spectrum analyzer
Measured power using spectrum
analyzer showing multiple bands

16. REALIZATION OF COMPLIANCE DISTANCE
 This exercise was done to
realize compliance zone for
a particular BTS/ antenna
Transmitted power, antenna
gain, frequency, antenna
height, tilt etc. were vary to
observe dependency of
these factors on compliance
distance.
 Observed Power Density
(Watt/m2)
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Distance(m)

17. Power Density(Watt/m2)
 GSM antenna with 4
carriers in one sector.
 It can be observed
that if power density
f/20000 will be
considered for the
compliance distance
then it can be seen
that observed
compliance distance
is between 14 to 18
m
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Distance (Meter)
Near field behavior of GSM antenna
with 4 carriers in one sector

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19. RADIATION SHIELD
 A “Radiation Shield” consisting of multiple
orthogonally polarized broadband monopole
antennas (800 to 4000 MHz)has been developed.
 The antennas are terminated in matched load to
absorb the harmful radiation to produce a safe
radiation free environment.
 It also has a LED which lights up (without battery)
when a strong radiation source is brought close to it.
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20. 10/24/201
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20  Indication of measured microwave power
in the frequency range of 800 MHz by
different LED colors has been decided

21. Biological Effects of Cell Tower
Radiation on Human Body
 Now days in most of the places the towers are
constructed over upon the building.
 Human body absorbs radiation, because human
body consists of 70% liquid.
 More than adults, children's are affected highly.
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22. Effect on Environment
 Effect on Honey Bees
 Effect on Birds
 Effect on mammals
and amphibians
 Effect on Plants
Effect on human body
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23. Case study
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 people living in the front side of the antenna will receive
much higher radiation compared to people living in the
back side of antenna.
 For a single transmitter, power density at R = 50m is equal
to 0.0318W/m2 = 31,800 μW/m2.
 Even for 3 transmitters in the same direction, it comes out
to be approximately 0.1 W/m2 = 100,000 μW/m2

25. RADIATION NORMS ADOPTED IN
INDIA AND OTHER COUNTRIES
 In India, we have adopted radiation norms given by
ICNIRP guidelines
 Safe power density is f/200, where frequency (f) is
in MHz
 For GSM900 transmitting band (935-960 MHz),
power density is 4.7W/m2
 For GSM1800 transmitting band (1810-1880 MHz),
it is 9.2W/m2.
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26. 10/24/201
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26 BANGLADESH
The Cell Phone providers having
installed the towers will be asked to
provide the following technical
details for operating parameters of
the installed towers for scientific
evaluation.
a. Peak power/frequency
from each Antenna
b. RF amplifier Model and its
specification
c. Type of Antenna and its
radiation pattern
d. Land clearance requirement
around a tower
GERMANY
a. <0.1 μW/m2 - no concern
b. 0.1 - 10 μW/m2 - slight
concern
c. 10 - 1000 μW/m2 - severe
concern
d. > 1000 μW/m2 - extreme
concern

27. Health concerns with current Safety Guidelines
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28. Conclusion
 The seriousness of the health hazards due to radiation from
cell towers has not been realized among the common man.
 Its effect on health is noted after a long period of exposure.
 The compliance distance varies with antenna gain,
transmitting power, frequency.
 Stricter radiation norms must be enforced across globe.
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29.  Mobile companies should not be in the denial mode.
 The radiation causes serious health problems.
 Only then people all over the world will carry out
research to come out with solutions.
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Cont.

30. References
 the Peculiar Circumstances of the IARC Working Group on Radio Frequency
Electromagnetic Fields and Cellular Telephones IEEE Antennas and
Propagation Magazine, Vol. 53, No.3, June 2011.
 Evaluation of RF EMF exposure pattern on selected communication towers in
Malaysia-2011.
 ICNIRP - International Commission on Non-Ionizing Radiation Protection -
Guidelines for limiting exposure to time-varying electric, magnetic, and
electromagnetic fields (up to 300 GHz), Health Phys, 1 sep 2012.
 Levitt B, Lai H, Biological effects from exposure to electromagnetic radiation
emitted by cell tower base stations and other antenna arrays, Environ. Rev.
18: 369–395, 2010 – http://article.pubs.nrccnrc.
gc.ca/RPAS/rpv?hm=HInit&journal=er&volume=18&calyLang=eng&afpf=a1
0-018.pdf
 N. Kumar and G. Kumar, Biological Effects of Cell Tower Radiation on Human
Body, IEEE Conf. ISMOT, pp.1365-1368, Dec. 2009.
 Z. W. Sim, R. Shuttleworth, and B. Grieve Investigation of PCB Microstrip
patch receiving antenna for outdoor RF energy harvesting in wireless sensor
networks, IEEE Conf. Antenna and Propagation Conference, Loughborough,
pp.129-132, Nov. 2009
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