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Member
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Modulation

I just want to Re open this topic. 

 

Does anyone else notice that FF cant hold modulation as stable as flexible. I find that it jumps around far more often while using FF.

 

I have lowered power and done all the things one would usually do to try stabalise it but power cant be the issue. If i change it to flexible and it sits pretty on 8 X .

 

It is usually the AP side modulation that fluctuates more. 

SuperUser
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Re: Modulation

There is a fundamental difference in the modulation rate reporting under the current flexible mode and the fixed/flexNG modes.

 

The current flexible mode uses some hardware retries. This means that those failures are automatically retried before airMAX can even participate. This results in modulation rates reported that are unrealistic. Flex lies.

 

Under fixed mode, this doesn't happen. Instead, all actions of the entire system are fully within the control of airMAX. The chip becomes more of a dumb data pump with a smart system in the background driving all decisions about whether the transmitter is on or off.

 

You should compare actual throughput for both modes.

 

The biggest disavantage with the fixed anf flexng modes is going to be the increase in latency (relative to the frame size) during low traffic periods. This modulation rate perception reporting is a distant second in disdvantages. I'm not sure if you would even call knowing the reality of the situation a disadvantage...

 

The biggest advantage of these new modes is that you get much more consistent throughput, even during peak loads. It also avoids certin quirks of not having airMAX in full control at times, quirks which can cause unexpected behaviour and problems in flexible mode.

Ubiquiti Employee
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Re: Modulation

Totally agree with @twinkletoes - this will be easier to compare in future with the new flexible mode as well.
SuperUser
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Re: Modulation

This lack of awareness and understanding of this _fundamental_ difference between Fixed/FlexNG and previous airMAX modes is a bit of a problem. This issue is crucial to someone who is comparing the reported data rates of previous airMAX implementations to the current one.

SuperUser
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Re: Modulation


@twinkletoes wrote:

This lack of awareness and understanding of this _fundamental_ difference between Fixed/FlexNG and previous airMAX modes is a bit of a problem. This issue is crucial to someone who is comparing the reported data rates of previous airMAX implementations to the current one.


Agree completely - it's kind of like when the transition from 802.11n to AirOS-M happened - it took a while and a lot of people seeing what was what before most people understood the benefits.   I'm afraid we're in for the same kind of thing this time, except that there are a ton more radios out there now...

Jim

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