User's Manual

Table Of Contents
Safety AR Standard Repeater
044-05250 Rev A 1-3
For antennas larger than 20cm the maximum radiation power can be calculated by using the
following formula:
where S = Radiation power in W/m²
P = Output power in W
r = Distance between antenna and human in meter
To tackle the worst case successfully, the calculation does not consider system power
reducing actions, such as power control and DTX. Figure 1-1 shows the safety distance to an
antenna due to the RF radiation. The distance depends on antenna output power and
frequency, which is illustrated with the two graphs. One graph applies to 4.5W/m
2
(900MHz)
and the other to 9.0W/m
2
(1800MHz) or 10.0W/m
2
(2100MHz). The safety distance range is 0
to 1.4 meters which covers an antenna power range of 10dBm to 50dBm (0.01W to 100W).
Radiation Safety Distances
This section illustrates the safety distances to the antennas for some typical repeater
configurations.
Outdoor GSM 900MHz
The safety distance can be read to 0.75 meter in Figure 1-1 as the maximum radiation power
is 4.5W/m
2
for 900MHz.
Indoor GSM 900MHz
The safety distance can be read to 0.035 meter for 4.5W/m
2
(900MHz).
Outdoor UMTS Standard High Power
The safety distance can be read to 0.9 meter for 10W/m
2
(2100MHz).
Repeater output power +33dBm
Feeder loss –5dB
Antenna gain +17dBi
Equivalent Isotropic Radiated Power (EIRP) +45dBm
Repeater output power +22dBm
Feeder loss –5dB
Antenna gain +1dBi
EIRP +18dBm
Repeater output power +38dBm
Feeder loss –5dB
Antenna gain +17dBi
EIRP +50dBm
S
P
4 π r
2
××
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=