4 Planning Considerations
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4.4 Variable Channel Bandwidth Operation
Channel bandwidths of 5, 10 and 15 MHz are supported for the PTP 300 product.
Configuration of the variable bandwidth operation must be symmetric, that is, the Transmit
and receive channels must use identical Channel Bandwidths.
For details of the spectrum settings that are available to each frequency variant, refer to:
•
Section
16.2.6 PTP 54300 Available Spectrum Settings
•
Section
16.3.6 PTP 58300 Available Spectrum Settings
4.5 Link Planning
4.5.1 Link Range
The PTP 300 Series Bridge operates at ranges from 100 m (330 ft) to 250 km (155 miles).
Operation of the system will depend on obstacles in the path between the units. Operation at
40 km (25 miles) or above requires a near line of sight path. Operation at 100m (330 ft) may
be achieved with one unit totally obscured from the other unit, but with the penalty of
transmitting at higher power in a non-optimal direction, thereby increasing interference in the
band.
4.5.2 Line Of Sight Mode
To permit higher data throughput rates over links of range 10 km (6.2 miles) or less, the PTP
300 Series Bridge can be configured to operate with Line Of Site mode enabled.
The line of sight capability must be enabled in the license key. This requires purchase of an
upgrade access key.
Line Of Site mode may be used only when the path is completely unobstructed and the link
range is less than 10 km (6 miles). An unobstructed path is one in which the first Fresnel zone
is clear of obstructions and there is zero excess path loss. The PTP LINKPlanner provides
capabilities to check for obstructions in the path.
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