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John Galt
Forward, March
Premium
join:2004-09-30
Happy Camp
kudos:8

2 edits

AirView Spectrum Analyzer Anomaly

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jcremin See Profile asked a question in another thread that wasn't answered, and I thought it warranted a separate discussion as I see the same thing on my LocoM5s.

I checked the UBNT forums but nothing was found.

Does anyone else see this anomaly shown above on their units? It looks like the artifact repeats itself with some regularity up and down the band from the marked location.


Inssomniak
The Glitch
Premium
join:2005-04-06
Cayuga, ON
kudos:2
The seemingly impossible sharp increase in signal ? Yea Seen that a lot.
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WHT

join:2010-03-26
Rosston, TX
kudos:5
reply to John Galt
AirView often has unexplainable anomalies that don't show up on the MetaGeek spectrum analyzer.


John Galt
Forward, March
Premium
join:2004-09-30
Happy Camp
kudos:8
I've noticed that the 'defect' does not seem to manifest itself in the dongle version.

bburley

join:2010-04-30
Cold Lake, AB
I have no way of knowing the inner details for certain, but it looks like the band is broken into segments about 17 or 18 MHz wide. Switching circuits for each segment would change the RF tuning to optimize RX sensitivity and TX amplifiers for each segment.

The sharp increase in segment 3 (2434 - 2452) looks like a "DC Offset" which artificially raises the baseline. A true DC Offset wouldn't have noise appearing below the raised portion, but that would be like saying they haven't engineered their defects properly.

SipSizzurp
Fo' Shizzle
Premium
join:2005-12-28
Houston, TX
kudos:4
reply to John Galt
I suspect that it is not Airview, but the whole radio. In my initial testing of a 3 mile nanobridge link a few years ago I tried compliance mode for testing, and found a 12 dB link improvement in frequencies at around 5.8 Ghz and below. Like bburley suggests, I strongly suspect that the front end gain on these sub $100 radios is not all that uniform across the entire band.