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User Manual
Airbridge cBTS3612 CDMA Base Station
Power
f
[
MHz
=
S
1500
D.3 Estimation of Exposure to Electromagnetic Fields
Below method describes a theoretical approach to calculate possible exposure to
electromagnetic radiation around a base station transceiver antenna. Precise
statements are basically only possible either with measurements or complex
calculations considering the complexity of the environment (e.g. soil conditions, near
buildings
electromagnetic fields.
The maximum output power (given in EIRP) of a base station is usually limited by
license conditions of the network operator.
A rough estimation of the expected exposure in power flux density on a given point
can be made with the following equation. The calcualtions are based on FCC OET
65 Appendix B.
P
(
=
S
4
Whereas:
P = Maximum output power in W of the site
G
numeric
R = distance between the antenna and the point of exposure in meters
D.4 Calculation of Safe Distance
Calculations can be made on a site by site basis to ensure the power density is below
the limits given above, or guidelines can be done beforehand to ensure the minimum
distances from the antenna is maintained through the site planning.
. 1
=
r
Whereas:
r = distance from the antenna [m]
density
S
[mW/cm
]
880
=
=
. 0
58
mW
1500
and
other
obstacles)
∗
W
)
G
numeric
∗
∗
π
2
r
(
m
)
= Numeric gain of the antenna relative to isotropic antenna
64
*
G
*
Pt
d
π
4
S
Appendix D Electromagnetic Radiation
2
]
for
uncontrolled
2
/
cm
which
causes
D-3
System Description
area
at
880
reflections,
scattering
MHz
of
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