GE MDS Mercury 900, Справочное руководство

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172 Mercury Reference Manual 05-4446A01, Rev. E
Locations File. When the MAC address does not match, the radio
will ignore this information from the interfering AP and continue to
wait for valid scheduling information from an AP in the desired net-
work.
5.1.8 EIRP Compliance at 900 MHz
To determine the maximum allowable power setting of the radio, per-
form the following steps:
1. Determine the antenna system gain by subtracting the feedline loss
(in dB) from the antenna gain (in dBi). For example, if the antenna
gain is 9.5 dBi, and the feedline loss is 1.5 dB, the antenna system
gain would be 8 dB. (If the antenna system gain is 6 dB or less, no
power adjustment is required.)
2. Subtract the antenna system gain from 36 dBm (the maximum
allowable EIRP). The result indicates the maximum transmitter
power (in dBm) allowed under the rules. In the example above, this
is 28 dBm.
3. Set the transmitter power so that it does not exceed the maximum
level determined in Step 2.
(
Main Menu>>Radio Configuration>>Transmit Power )
Refer to Table 5-4 , which lists several antenna system gains and shows
the maximum allowable power setting of the radio. Note that a gain of
6 dB or less entitles you to operate the radio at full power output
–30 dBm.
For MDS 3650 units, refer also to the section titled EIRP Compliance at
3650 MHz below.
* Most antenna manufacturers rate antenna gain in dBd in their litera-
ture. To convert to dBi, add 2.15 dB.
** Must use with the appropriate length of feedline cable to reduce
transmitter power by at least 2 dB. Feedline loss varies by cable
type and length. To determine the loss for common lengths of feed-
line, see
Table 5-1 on Page 167 .
Table 5-4. Antenna Gain vs. Power Setpoint (900 MHz)
Antenna System Gain
(Antenna Gain in dBi*
minus Feedline Loss in dB)
Maximum Power Setting
(PWR command)
EIRP
(in dBm)
Omni 6 (or less) 29 35
Omni 11 25 36
Yagi 11 23 36
Half Parabolic 16 20 36
Panel 17.4** 20 36