User manual

SM User Manual January 2004
Software Release 4.1
5 SITE PLANNING
The following considerations are critical in the choice of a location for the wireless network
infrastructure.
Note: Since each site is unique, typically many additional considerations are critical.
5.1 SELECTION OF SM TYPES AND PASSIVE REFLECTORS
A system plan may include
• SMs that are not mounted to Passive Reflectors, operate in the 5.2-GHz band, and
communicate with an AP in the 5.2-GHz band.
• SMs that are not mounted to Passive Reflectors, operate in either the 2.4-GHz band or
the 5.7-GHz band, and communicate with an AP in the same band.
• SMs that are mounted to Passive Reflectors, operate in the 2.4-GHz band or the 5.7-
GHz band, and communicate with an AP in the same band.
The network planner should select the model of SM for each site based on
• an attempt to design for cross-band collocation of APs with BH timing masters (to
avoid self-interference). See Physical Proximity on Page 58.
• the constraint that both the AP and the SM must operate on the same encryption
standard. See Interoperability on Page 22.
• the distance of the SM from the AP. A Passive Reflector is required for each SM in the
5.7-GHz band that is further than 2 miles (3.2 km) from the AP and for each SM in the
2.4-GHz band that is further than 5 miles (8 km) from the AP.
See Types of SM Applications on Page 16.
5.2 SPECIFIC MOUNTING CONSIDERATIONS
The Canopy SM must be mounted
• vertically (the internal antenna is vertically polarized).
• with hardware that the wind and ambient vibrations cannot flex or move.
• where a grounding system is available.
• at a proper height:
– higher than the tallest points of objects immediately around them (such as trees
and buildings).
– at least 2 feet (0.6 m) below the tallest point on the roof or antenna mast (for
lightning protection).
• in a line-of-sight path
– to the AP in the RF link.
– that will not be obstructed by trees as they grow or structures that are later built.
Note: Visual line of sight does not guarantee radio line of sight.
Issue 5 Page 47 of 119