User's Guide

Table Of Contents
7 Web Page Reference
116
Link Symmetry is subject to the following restrictions:
"Adaptive" is not supported in regions where radar avoidance is in use.
"Adaptive" is not supported when link optimization is set to "TDM".
"Adaptive" is not supported in 5 MHz channel bandwidth.
"3 to 1" and "1 to 3" are not supported in 5 MHz channel bandwidth.
“3 to 1” and “1 to 3” are not supported when E1/T1 services are enabled.
Spectrum Management Control
Is used to configure the PTP 500 Series Bridge’s Spectrum Management features, see
Section 7.9 “Spectrum Management” for more details. In regions that do not mandate DFS
(Rada
r Detection), the Spectrum Management Control options are “i-DFS” and “Fixed
Frequency”. In regions that mandate DFS (Radar Detection), the Spectrum Management
Control options are “DFS” and “DFS with i-DFS”.
Lower Center Frequency
Not displayed when Spectrum Management Control is set to “Fixed Frequency”. The software
for the PTP 500 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.
CAUTION
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.
Default Raster
If this is set to “On”, the list of options presented in the fixed Tx frequency box is limited by the
default raster.
Fixed Tx Frequency, Fixed Rx Frequency
Only displayed when Spectrum Management Control is set to “Fixed Frequency”. The
software for the PTP 500 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-channel or adjacent channel interference. Therefore
this mode of operation is only recommended for deployments where the installer has a good
understanding of the prevailing interference environment.
Figure 60 shows an example fixed frequency config
uration for a 15 MHz channel bandwidth.
In this example, the Fixed Transmit Frequency is set to 5735 MHz and the Fixed Receive
Frequency is set to 5735 MHz. Care must be taken when configuring the Fixed Transmit and
Receive Frequencies to ensure that both frequencies are on the same channel raster as the
Lower Center Frequency. For example, if the channel raster is 5 MHz, both the Fixed
Transmit and Receive Frequencies must be a multiple of 5 MHz from the Lower Center
Frequency (5740 = 5735 + 5 MHz) and (5745 = 5735 + 5 MHz x 2).