802.11
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I just installed 2 Ubiquiti Rocket AC radios. Can anyone explain in English what the constelllation map is and what information it prprovides
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Randall,
Disclaimer: I am not a radio engineer and have no license to be one. But...that will not prevent me from giving you an answer!
As I understand it. What you're seeing from the awesome Ubiquiti Software requires an understanding of the following:
1. RF Antennae
2. Terminology
3. Ubiquiti's ability to report on something you cannot control.
When signal goes out, there is an expectation of how that signal leaves the antenna (vector--it's supposed to go this way). So there is a reference angle, path, whatever that the signal is supposed to travel.
There is also the reality that signals go where signals go (actual vector--it's going this way instead). This is a deviation from the reference...which represents an error.
The difference between how it's supposed to go this way and the way it's going is called EVM (Error Vector Magnitude). This expression is normally a ratio. A flawless signal leaving the antenna would have ratio of 0.
Ok...so this ratio is the space between reference and reality that constellation.
So your constellation shows you graphically what may be the noise or distortion mechanism degrading the EVM and causing that ratio to go higher. You may change some configuration on your ROCKET AC and come back to constellation and you see the symbols change. The more diffuse the constellation the greater the impairment on your signal; the more tightly grouped the better the signal is closer to the reference vector--in other words the better your access point is functioning without interference from anything.
Though, neat. You and I would not tend to use them, except in the way I'm describing for your ROCKET AC. Change configuration and see if your constellations are closer together...if not change it back...if so keep the change. But this is normally for people who design equipment.
Hope this clarifies rather than muddles!
Cordially,
Ronnie Wong
Host, ITProTV