256-QAM vs 64-QAM

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What is SNR requirement for 256-QAM vs 64-QAM?
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Ville Franck

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Posted 5 years ago

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EvaldasOu

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Hi Ville,

As you know noise affects dense signal and 256-QAM is of course more dense than 64-QAM. 802.11ac maximum throughput range should be short!
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Derek O'Sullivan

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So realistically, to get anywhere near the theoretical throughput from 802.11ac, the SNR has to be pretty high for the 256-QAM benefit, otherwise its pointless even deploying 802.11ac?
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Nick Lowe, Official Rep

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The channel width is higher, remember, so it's not pointless.
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Derek O'Sullivan

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ah ok, fair point.
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Craig Mathias

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Based on the work I've done so far, I'd say .11ac has some real benefits for everyone. OK, will it be able to deliver at the upper bounds? We're going to ask Matthew exactly that shortly.
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Derek O'Sullivan

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ok, will be interesting to see his view on it!
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Matthew Gast

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The spec has a minimum performance requirement: for an 80 MHz channel, receiver sensitivity for 256-QAM is -53 dBm, but for 64-QAM it's -58 dBm. And 5 dB is a lot - it's probably a wall-and-a-half or two walls of signal loss.
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Derek O'Sullivan

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ok, that is pretty good actually, a lot more room to play with than I thought.