Motorola MOTOWI 4 PTP 600 Series, Руководство пользователя системы

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Spectrum Management Control:
Is used to configure the PTP 600 Series Bridge’s
Spectrum Management features, see Section
1106H
8.3.7 for more details. i-DFS is the abbreviation
for intelligent Dynamic Frequency Selection. This feature continually monitors the spectrum
looking for the channel with the lowest level of on channel and co-channel interference. Fixed
frequency mode allows the installer to fix transmit and receive frequencies on the units. The
frequencies may be configured symmetrically or asymmetrically.
Lower Center Frequency:
The software for the PTP 600 Series Bridge allows a user to
optionally adjust the channel center frequencies. Changing the Lower Center Frequency
attribute causes all channel center frequencies to be offset. It effectively slides the
channelization up or down. See Sections
1107H
5.5 and
1108H
5.7 for more detail.
Warning
: The lower center frequency attribute must be configured to the same value for both
the master and slave. Failure to do so will cause the wireless link to fail reestablishment. The
only way to recover from this situation is to modify the Lower Center Frequency attribute so
that they are identical on both the master and slave unit.
Fixed Transmit Frequency, Fixed Receive Frequency:
The software for the PTP 600
Series Bridge allows a user to optionally fix the Transmit and the Receive frequencies for a
wireless link. The settings must be compatible at each end of the link. Once configured the
spectrum management software will not attempt to move the wireless link to a channel with
lower co or adjacent channel interference. Therefore this mode of operation is only
recommended for deployments where the installer has a good understanding the prevailing
interference environment.
1109H
Figure 60
1110H
shows a sample fixed frequency configuration for a 30
MHz channel bandwidth. In the example the lower center frequency is set to its default values
and the Fixed Transmit Frequency is set to 5742 MHz and the Fixed Receive Frequency is
set to 5742 MHz. Care must be taken when configuring the Fixed Transmit and Receive
Frequencies to ensure that both frequencies are on the same 10 MHz channel raster as the
Lower Center Frequency. For example both the Fixed Transmit and Receive Frequencies
must be a multiple of 10 MHz from the Lower Center Frequency (5752 = 5742 + 10 MHz) and
(5782 = 5742 + 10 MHz
×
3). See Sections
1111H
5.5 and
1112H
5.7 for more detail.