
1 About This User Guide
9
1.8.4 Calculated Distances and Power Compliance Margins
Table 3 shows calculated minimum separation distances
d
, recommended distances and
resulting power compliance margins for each frequency band and antenna combination.
These are conservative distances that include compliance margins. At these and greater
separation distances, the power density from the RF field is below generally accepted limits
for the general population.
Table 3 - Power Compliance Margins
Variable
Band Antenna
Max
Average
Transmit
Power in
Burst
(Watt)
P
(Watt)
G
S
(W/m
2
)
d
(m)
Recom-
mended
Distance
(m)
Power
Compliance
Margin
Integrated
0.005
(7 dBm)
0.00250
200
(23 dBi)
10
0.06
5.4
GHz
External
4ft Dish
0.00035
(-4.6 dBm)
0.00017
2884
(34.6 dBi) 10
0.06
1 15.9
Integrated
0.020
(13 dBm)
0.01
200
(23 dBi)
10
0.13
1
7.6
EU
5.8
GHz
External
4ft Dish
0.0014
(-1.4 dBm)
0.0007
2884
(34.6 dBi) 10
0.13
1
7.6
Integrated
0.32
(25 dBm)
0.16
200
(23 dBi)
10
0.5
2
4.0
External
2ft Flat
Plate
0.32
(25 dBm)
0.16
631
(28 dBi)
10 0.9
4
4.5
FCC
5.8
GHz
External
6ft Dish
0.32
(25 dBm)
0.16
6310
(38 dBi)
10 2.83
10
3.5
NOTE
The regulations require that the power used for the calculations is the maximum
power in the transmit burst subject to allowance for source-based time-averaging.
At 5.4 GHz and EU 5.8 GHz, the products are generally limited to a fixed EIRP which
can be achieved with the Integrated Antenna. The calculations above assume that
the maximum EIRP allowed by the regulations is being transmitted.
If there are no EIRP limits in the country of deployment, use the distance calculations
for FCC 5.8 GHz for all frequency bands.
At FCC 5.8 GHz, for antennas between 0.6m (2ft) and 1.8m (6ft), alter the distance
proportionally to the antenna gain.
4Gon www.4Gon.co.uk [email protected] Tel: +44 (0)1245 808195 Fax: +44 (0)1245 808299