Cambium Networks ePMP, Руководство пользователя

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CAMBIUM NETWORKS
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Calculation of power density
Peak power density in the far field of a radio frequency point source is calculated as follows:
Note
The following calculation is based on the ANSI IEEE C95.1-1991 method, as that provides a
worst case analysis. Details of the assessment to EN50383:2002 can be provided, if required.
Where: Is:
S power density in W/m 2
P maximum average transmit power
capability of the radio, in W
G total Tx gain as a factor, converted
from dB
d distance from point source, in m
Rearranging terms to solve for distance yields:
Calculated distances and power compliance margins
The calculated minimum separation distances, recommended distances and resulting margins for
each frequency band and antenna combination is shown in
Table 134 through Table 154 . 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.
Explanation of terms used
Table 130 through Table 154 :
Tx burst – maximum average transmit power in burst (Watt)
P – maximum average transmit power capability of the radio (Watt)
G – total transmit gain as a factor, converted from dB
S – power density (W/m
2
)
d – minimum distance from point source (meters)
R – recommended distances (meters)
C – compliance factor
2
4
.
d
G P
S


S
G P
d
. 4
.

