User's Guide

PTP 250 User Guide Regulatory planning
phn-2182_003v004 (Oct 2011)
UNDER DEVELOPMENT
2-5
Avoidance of weather radars (USA only)
To comply with FCC rules ( KDB 443999: Interim Plans to Approve UNII Devices Operating
in the 5470 - 5725 MHz Band with Radar Detection and DFS Capabilities
), units which are
installed within 35 km of a Terminal Doppler Weather Radar (TDWR) system (or have a
line of sight propagation path to such a system) must be configured to avoid any frequency
within +30 MHz or –30 MHz of the frequency of the TDWR device.
This requirement
applies even if the master is outside the 35 km radius but communicates with outdoor
clients which may be within the 35 km radius of the TDWRs.
The requirement for ensuring 30 MHz frequency separation is based on the best
information available to date. If interference is not eliminated, a distance limitation based
on line-of-sight from TDWR will need to be used. In addition, devices with bandwidths
greater than 20 MHz may require greater frequency separation.
When planning a link in the USA, visit http://spectrumbridge.com/
udrs/home.aspx, enter
the location of the planned link and search for TDWR radars. If a TDWR system is located
within 35 km (22 miles) or has line of sight propagation to the PTP device, perform the
following tasks:
• Register the installation on http://spectrumbridge.com/
udrs/home.aspx.
• Use Table 2-2 to
identify channel center frequencies that must be unselected, that is,
those falling within +30 MHz or –30 MHz of the frequency of the TDWR radars.
• Specify these channels in the installation report.
Table 2-2 Channels to be avoided when close to TDWR radars
PTP 250 channel
width
TDWR frequency Channels to be unselected in
Step 2: Wireless Configuration
20 MHz <= 5610 MHz 5580 (116)
20 MHz >= 5630 MHz 5660 (132)
40 MHz >= 5630 MHz Channel pair 5660 & 5680 (132 & 136)
To comply with FCC rules, the affected channels must be unselected during staging,
before the units are allowed to radiate on site, as described in Step 2: Wireless
configuration on page 6-16.