Users Guide

Table Of Contents
Parameter Description
Non Wi-Fi Devices Number of Non-Wi-Fi (interfering) devices detected/classified by the
spectrum monitor.
Center Freq. (GHz) Center frequency of the Wi-Fi signals sent on that radio channel.
Channel Util. (%) Percentage of the channel currently being used by devices on the
network.
Max AP Power (dBm) Signal strength of the AP that has the maximum signal strength on a
channel.
Max Interference (dBm) Signal strength of the non-Wi-Fi device that has the highest signal
strength.
SNIR (dB) The Signal-to-Noise-and-Interference Ratio (SNIR) is the ratio of signal
strength to the combined levels of interference and noise on that
channel. This value is calculated by determining the maximum noise-
floor and interference-signal levels, and then calculating how strong the
desired signal is above this maximum.
Device Duty Cycle
The Device Duty Cycle Chart is a stacked bar chart that shows the duty cycle of each device type on a channel.
The duty cycle is the percentage of time each device type operates or transmits on that channel. Though Wi-Fi
devices do not transmit if there is another Wi-Fi or non-Wi-Fi device active at that time, most non-Wi-Fi devices
do not follow such a protocol for transmissions. Because these devices operate independently without regard
to any other devices operating on the same channel, the total duty cycle of all device types may add up to
more than 100% on a channel. For example, one or more video bridges may be active on a channel, each with a
100% duty cycle. The same channel may have a cordless transmitter with a 10% duty cycle and a microwave
oven with a 50% duty cycle. In this example, the Device Duty Cycle chart shows all three device types with their
respective duty cycle percentages.
A hybrid AP on a 20 MHz channel will see 40 MHz Wi-Fi data as non-Wi-Fi data.
Spectrum monitors display spectrum analysis data seen on all channels in the selected band, and hybrid APs
display data from the one channel they are monitoring. The example below shows data from a spectrum
monitor monitoring all channels in the 2.4 Ghz band.
Dell Networking W-Series ArubaOS 6.5.x | User Guide Spectrum Analysis | 759