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Before You Begin
Perform a Site Survey
Perform a Site Survey
Before installing the CMAP, perform a site survey to determine the optimal access point
placement for maximum range, coverage, and network performance. When performing a
site survey, consider the following factors:
■
Data rates
: Range is generally inversely proportional to data rates. The maximum radio
range is achieved at the lowest workable data rate. Higher data rates will generally be
achieved at closer distances.
■
Physical environment
: Clear or open areas provide better radio range than crowded
or filled areas. The less cluttered the operating environment, the greater the wireless
range.
■
Obstructions, building materials, and sources of interference
: Physical obstructions,
such as concrete pillars, steel beams, filing cabinets, buildings, or trees, can block or
hinder wireless communication. Avoid installing the CMAP in an environment where
there is an obstruction between sending and receiving devices. A number of machines
and electronic devices that emit radio waves – wireless phones, microwave ovens,
satellite dishes – interfere with and block wireless signals. Building materials used in
construction also influence radio signal penetration. For example, drywall construction
permits greater range than concrete blocks.
■
Mounting:
The CMAP is designed to hang on a 1/4 to 3/8" support wire. The hangers
will allow a 2" bundle of cables between the support wire and the CMAP.
■
Power and backhaul connections
: Of course, the CMAP needs a backhaul connection
to the CMTS and it needs to be close enough to an AC power inserter on the CATV
cable to assure that it will be able to pull 60 watts at greater than 45 VAC. If not, then
another power inserter must be installed closer to the CMAP. The CATV signal level
must be roughly 5 dBmV at the tap connection to the unit.
