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System Planning 84
Regulatory limits
Many countries impose EIRP limits (allowed EIRP) on products operating in the bands used by the 60
GHz cnWave. These are commonly identified by limitations on conducted transmit power or by antenna
gain. For example:
Table 32: ERC recommendation (70-03)
Frequency
Band Power / Magnetic Field
c2 57 - 71
GHz 40 dBm E.I.R.P., 23 dBm/MHz E.I.R.P. density and maximum transmit power of 27
dBm at the antenna port/ports.
c3 57-71
GHz 55 dBm E.I.R.P., 38 dBm/MHz E.I.R.P. density and transmit antenna gain ≥ 30 dBi.
CFR47 Part 15.255(c)(ii):
For fixed point-to-point transmitters located outdoors, the average power of any emission shall not
exceed 82 dBm and shall be reduced by 2 dB for every dB that the antenna gain is less than 51 dBi. The
peak power of any emission shall not exceed 85 dBm, and shall be reduced by 2 dB for every dB that the
antenna gain is less than 51 dBi.
Link planning
This section describes factors that must be considered when planning links, such as range, obstacles path
loss, and throughput. It is highly recommended to use Cambium LINKPlanner software when planning the
links.
LINKPlanner
The Cambium LINKPlanner software and user guide may be downloaded from the support website (see
https://support.cambiumnetworks.com/files/linkplanner/ ).
LINKPlanner imports path profiles and predicts data rates and reliability over the path. It allows the
system designer to try different antenna heights and RF power settings. It outputs an installation report
that defines the parameters to be used for configuration, alignment, and operation. Use the installation
report to compare predicted and actual link performance.
Exclusion zones for the 59 – 63.9 GHz band
In the three geographical areas outlined in 59 - 63.9 GHz Transmission Exclusion Zones (UK IR 2078
Section 4 and IR 2030 IR2030/7/4 (2018/316/UK)), no transmissions are permitted.
Table 33: 59 - 63.9 GHz transmission exclusion zones
Site Name Site Location Radius of exclusion zone from the center of site location
Site 1 07° 23’ 36.6” W, 57° 21’ 3.6” N 6 Km
Site 2 04° 58’ 21” W, 51° 37’ 16.8” N 6 Km
Site 3 00° 36’ 22.8” W, 52° 38’ 1.8” N 6 Km
Range and obstacles
Calculate the range of the link and identify any obstacles that may affect radio performance.