Chapter 4
Tropos 7320 Router Installation Guide
57
Note
Luxembourg does not permit point-to-point installations in the 802.11a/n band (5.470-5.725 GHz).
Attenuation with External Antennas
If external antennas are used, it is necessary to adjust the transmit power attenuation to provide
the correct power level for the router. Use the following formulas to compute the required
attenuation level:
Gain’ (dBi) = Antenna Gain (dBi) - Cable Loss (dB)
802.11b/g/n:
802.11a/n:
TABLE 17
802.11a/n Radio (5470-5725 MHz) - Antenna Configurations
Description
Part
Number
Measured Cond.
Avg. Power
(dBm)
Tx Attenuation
Software
Setting (dB)
Approximate
EIRP
9.1dBi omni, unit mounted
[8dBi (5470-5725 MHz)]
AN091058 21.8
0
29.8
17dBi 90° sector, external bracket
mounted
a
a.
All external antennas include pole mounting bracketry and sealing materials. RF cables are not included.
AN170054 12.5
7
29.5
19dBi patch antenna, external
bracket mounted
AN190054 9.8
9
29.8
Tx Antenna Setting (dB) =
4
Gain’ - 3
if Gain’ < 7 dBi
if Gain’ > 7dBi
Tx Antenna Setting (dB) =
0
Gain’ - 9
if Gain’ < 9 dBi
if Gain’ > 9 dBi