Public Safety Product Antennas
Tropos Mobile Router Installation Guide
23
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:
Table 10 802.11a Antenna Configurations for Public Safety (4940-4990 MHz)
Antenna
Ordering
Number
Channel
Bandwidth /
Operating
Frequency (MHz)
Measured
Conducted
Power (dBm)
Tx
Attenuation
Software
Setting (dB)
Approximate
EIRP (dBm)
9.0dBi omni, magnetic
mount
AN090049
20
4950 - 4980
20.0
4
29.0
9.0dBi omni, magnetic
mount
AN090049
10
4945 - 4985
17.0
7
26.0
9.0dBi omni, magnetic
mount
AN090049
5
4945 - 4985
14.0
10
23.0
6.0dBi omni, magnetic
mount
AN060049
20
4950 - 4980
20.0
4
26.0
6.0dBi omni, magnetic
mount
AN060049
10
4945 - 4985
17.0
7
23.0
6.0dBi omni, magnetic
mount
AN060049
5
4945 - 4985
14.0
10
20.0
5.0dBi omni, vehicle
mounted
AN050049
20
4950 - 4980
20.0
4
25.0
5.0dBi omni, vehicle
mounted
AN050049
10
4945 - 4985
17.0
7
22.0
5.0dBi omni, vehicle
mounted
AN050049
5
4945 - 4985
14.0
10
19.0
Tx Antenna Setting (dB) =
0
Gain’ - 7
if Gain’ < 7 dBi
if Gain’ > 7dBi
