573| Spectrum Analysis DellPowerConnect W- Series ArubaOS 6.2 | User Guide
GraphTitle Description Update
Interval
interferencepower data for multipl e channels, while a hybrid AP shows
information only fori tsone moni toredchannel . For details, see
"Interference Power" on page 598.
Quality
Spectrogram
Thispl ot shows quality statisticsfor selected range of channel s or
frequenciesas determined by the current noise floor, non-Wi-Fi (interferer)
utilization and duty-cyclesand certain types of retries. This chart can also
beconfigured to show channel avail ability, the percentage ofeach
channel thatis unused and available for additional traffic. Spectrum
monitorscan show data for multipl e channels, while a hybrid AP shows
information only fori tsone moni toredchannel . For details, see "Quality
Spectrogram"on page 600.
Updatesevery 5 seconds
Real-Time FFT FastFourier Transform, or FFT, is an algori thm forcom puting thefrequency
spectrumof a tim e-varying input signal. This line chart shows the power
level ofa signal on the channels or frequencies monitored by a spectrum
monitor radio. Spectrum monitors can show data for multiple channels,
while a hybrid AP shows information only for its one monitored channel.
Thischart i s notavai lable for W-AP120 Series or W-AP68 access points.
Fordetails, see "Re al-TimeFFT" on page 601.
Updatesevery second
Swept
Spectrogram
Thispl ot displays FFTpow er levels For details, see or the FFT duty cycle for
aselected channel or frequency, as measured during each time tick.
Spectrumm onitors can show datafor mul tiple channels, while a hybrid AP
showsinformation onl yfor its one monitored channel.
Thischart i s notavai lable for W-AP120 Series or W-AP68 access points.
Fordetails, see "Swe ptS pectrogram"on page 603.
Updatesevery second
Spectrum Analysis Clients
The maximumnumber of spectrum monitor radios andhybrid AP radios on a controller is limited only by the
numberof AP s on that controller.I f desired,y ou can configureevery radio on an A P that supports the Spectrum
Analysis feature as a spectrum device. A dual-radio AP can operate as two spectrum devices, since each radio can be
individuallyco nfiguredas a spect rummonito r (SM)or hybrid A P.
A spectrum analysis client can simultaneouslyaccess data from up to four individual spectrum device radios. Each
spectrumdevic e radio, however,can only be co nnectedto a si ngleclient WebUI.
Whenyou select a specific spectrum monitor or hybrid AP radio to stream data to yourclient, the controller first
checks the availability of the device, to verify that it is not subscribed to some other client. Once the SM or hybrid
AP radio has been verified as available,the SM or hybrid AP establishes a connection to t heclient and begins
sendingspect rumanalysis data either every second or every five seconds, dependingon the type of data being
requested.Each client may select up to twelve differentspectrum analysis charts and graphsto appear in the
spectrumdashboard.
A controller can support up to 22 active WebUI c onnections. If spectrum analysis clients are simultaneously viewing
data fort han22 WebUI connections, any additional WebUI requestsare refused until someclients close their
WebUI browser sessions.
Whenyou finish reviewi ngdata from an SM or hybrid AP, you should disconnect the device from your spectrum
client. Do not forget this important step—no ot heruser can access data from that spectrum monitor o r hybridA P
until you releasey oursubscripti on. Note, however, that when you disconnect a spectrum monitor from your client,
the AP continues to operate as a spectrum mon itor until you return it to AP mode by removing the local spectrum
override,or by changing the mode parameter in the AP’s 80 2.11a or 802.11g radio profile from spectrum-mode back
to AP-mode.