User's Manual

PMP 400/430 and PTP 200/230 Series Motorola PMP Solutions User Guide Supplement
Issue 6.0 May 2011 Page 36 of 77
Table 11: 4.9 GHz Channel Center Frequencies
Range of Center Frequencies Available (MHz)
(on 5 MHz centers within this range, inclusive)
Number of
center
channels
Maximum number of
non-overlapping
channels
4945 - 4985
9
5
The best practice for channel planning for APs is to conduct extensive site RF surveys before
choosing channels. The SM provides a basic Spectrum Analyzer that can be used for site
surveys. For more sophisticated analysis, consider consulting an experienced RF engineer and
using a full-featured spectrum analyzer.
3.2 DOWN TILT
The standard AP antenna produces a 3 db beam elevation (up and down) of 5°, with near-in null
fill that allows good coverage of close-in SMs that otherwise would be affected by the narrow
pattern. This is a narrower pattern than operators may be used to with standard Canopy’s 60° 3
dB beam, and may require down tilt on the antenna. The bracket of the standard antenna has
provision for measured down tilt. The recommended practice is to use one of the many radio
analysis and mapping tools or on-line tools to calculate down tilt based on antenna height above
the service area.
3.3 WEATHER RADAR
Spectrum between 5600 and 5650 MHz (sometimes called the “weather notch”) is used by some
weather radar and is not allowed for use by regulations in some regions, including US, Canada
and, for new equipment, Europe. When the Canopy module is set to either of those regions
(configured on the Configuration => General page of the module), it will not allow configuration of
the appropriate frequencies, as shown in
Table 10. Even in regions where use of the spectrum
between 5600 and 5650 MHz is allowed, the best practice is to not use these channels if there
are any other usable channels available. Only use the channels in this “weather notch” after
monitoring the spectrum for a week or more using a spectrum analyzer to ascertain the spectrum
is clear and there is no weather radar in the area that will cause interference to your Canopy
system.
3.4 RANGE AND THROUGHPUT PLANNING
PMP 430 and PTP 230 5.4 and 5.8-GHz series modules provide 45+ Mbps aggregate throughput
at distances of 1.2 miles (1.92 km) and 2.3 miles (3.68 km) respectively. PMP 400 and PTP 200
Series modules provide up to 21 Mbps aggregate throughput at distances of 1.4 miles (2.25 km)
in RF environments with clear line-of-sight and low background interference levels. Additional
performance details are shown in
Table 8 on page 32. RF environments with occluded Fresnel
zones or higher background interference levels may give lower, but still very good, performance,
depending on the specifics of the environment.
Similar to standard Canopy, at any given instant, any radios operating at 1X or 2X take more “air
time” to transmit a given amount of data than if they were running at 3X. Similar to standard
Canopy, PMP 400/430 and PTP 200/230 Series modules may see reduced total throughput when
handling traffic with a high percentage of small packets.
The effect of this, again similar to standard Canopy, is that at any given instant total throughput
depends on
Mix of links running at 3X, 2X, and 1X
Mix of packet sizes