Wireless site survey
Session Objectives
• What is site surveying?
• Identify the importance of site surveying
• Identify items a wireless site survey should
disclose
• Identify the site surveying tools
• Site surveying methods
• How different vendor equipment impacts site
surveying
• How different technologies impacts site
surveying
What is a Wireless Site Survey?
• A series of procedures using specific wireless equipment
to identify proper wireless coverage in a given area for a
wireless local area network.
– Identify any interference sources
• either work around the interference
• propose eliminating the interference
– Identify the need for specific antenna usage and its
characteristics
– Identify the dB gain of the antenna
– Identify the directional properties
– Identify throughput requirements based on users and equipment
to determine access point placement
– Identify type of wireless devices to be used and types of
applications to be used
– Idendify maximum number of devices/users
Importance of Wireless Site
Surveying
• Without a site survey, everyone assumes wireless coverage is
complete and adequate when in fact the opposite is normally true
because:
– Wireless interference may occur without knowing where or why within
the wireless coverage area
– Wireless security is often overlooked and radio frequency spillage
occurs in unwanted areas like public streets or other buildings
– Inadequate coverage occurs without knowing the proper number of
access points and antennas required for a given coverage area
– Lack of wireless coverage testing results in coverage gaps where no
coverage exists
– Depending on the antenna placement and environment, multipath
distortion will cause too many null zones where no coverage exists.
– With site surveying, one can guarantee the coverage
A Site Survey Should...
• Disclose problem (radio interference) areas
• Identify the technology needed for a given
coverage area
• Identify the equipment that can and cannot work
with existing WLAN technology
• Determine the total number of access points and
antennas needed
• Identify the type of access points
• Identify the type of antennas
• Identify the need for any antenna accessories
• Identify the need for any security issues
The Need for Site Surveying
• Before a company decides on a wireless network or a
wireless site survey, they need to be able to answer a
wireless questionnaire that includes the following:
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How many users?
What type of wireless devices?
What type of applications are being used on these devices?
What type of throughput is required?
How many wireless sites?
What are the characteristics and dimensions of the sites?
Do the sites include multiple floors of coverage?
After these and other questions are answered, a site survey can
be scheduled with the proper equipment for specific dates
Site Surveying
• There are many tools that can be used for
a site survey.
• These tools are discussed later.
• Bring only the tools that are right
specifically site
• survey job based on customer needs.
• An analysis of the survey sites must be
done to determine if additional equipment
is needed i.e., lift bucket for high ceilings
Site Survey Tools
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Access points
Antennas
Client devices
Test software
Power source
Mounting hardware
Digital Camera
Accessories
Site survey plan
Floor layouts
Site Surveying Methodology
• In site surveying, there are many different site
surveying methods and everyone has their own
unique method in determine wireless coverage.
• The most popular of these methods are:
– "Outside-In" method
• This method assumes an omni-directional antenna is used
– "T" method
• This method assumes a directional antenna is used
– "3-D" method
• This method assumes coverage is provided on more than
just one floor of a multi-floor building