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Chapter 15 Test Results
OneExpert DSL User's Guide
22052280, Rev. 015 April 2019 274
Best Channels
A table that identifies the current top 3 best channels based on channel width for the
band being viewed. This helps determine which channel to select for a new access point.
Spectral results
The Spectral results provide a real-time spectral analyzer configurable by 802.11 band,
channel, and channel width. It is helpful for finding signals that interfere with 802.11
networks by showing both 802.11 and non-802.11 RF signals within a given channel of
interest.
The Spectral results screen includes the spectral graph area, where the real-time spectral
data is displayed, and the controls area, where the user can configure the spectrum
analyzer ranges and modes.
The Spectrum Analyzer controls consist of the following:
• Channel width – Specifies the width of the spectrum analyzer.
• Max Hold – The blue line above the standard spectral line that represents the peak
value (in dBm) seen at each frequency point. Press OK to reset the Max Hold trace
and restart the measurement.
• Averages – Specifies the number of samples to be used for averaging of the real-
time trace
The following are some common interferences that could show up in a spectral
measurement.
Microwave ovens can interfere with an 802.11 signal. They are most prevalent in channels 10
and 11. If possible, it is a good idea to look at the spectral response while the microwave is
running to determine it’s impact.
Bluetooth devices appear as spikes and appear to “roll” through the spectral view. They are
fast moving and you may only see them occasionally. The systems are designed to be inter-
operable, but Bluetooth will impact throughput.
Channels can “bleed over” into adjacent channels. The width of the signal (due to RF
considerations) can affect nearby channels. This bleed over is treated as noise.
NOTE:
The BSSID View and Channel View must be run first in order
for the BSSID and Channel Snapshots to populate in Spectral.