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Comment by Aurornis | Hacker News Reader

Others have already covered the legal problems with this. I’ll add that going over 1W or even less with typical WiFi gear can introduce enough distortion to offset the power gains.

WiFi hardware is cost optimized. It’s likely that the PA chips in your radio are going to distort if pushed past the legal limits. Many radios distort heavily past 100mW.

Its common for people to turn the power setting all the way up thinking they’re getting the best performance, but best performance might occur at a lower setting.

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Someone trained/learned/schooled in this stuff might know that. But for a curious hacker getting at the internals of how something works, the first instinct is to turn it up. That's their learning path. It's natural curiosity. More must be better. Louder must be better.

The point is to stop scaremongering about letting people turn up the TX. It's just a damn WiFi radio. They aren't going to be blocking their neighbor from listening to their favorite ClearChannel session of commercials. At most their neighbor might get a bit of interference. But if you're running on the same channel as your neighbor, you're already asking for trouble. Nobody's going to emergency, nobody's going to jail. We're not talking about firing up an 100kW flame thrower of a radio signal here. Let's just everyone keep their knickers on and realize the context of what we're discussing

> But for a curious hacker getting at the internals of how something works, the first instinct is to turn it up. That's their learning path. It's natural curiosity. More must be better. Louder must be better.

If you increase the TXpower way beyond the P1dB of your PA, you will introduce distorsion and therefore harmonics beyond your operating band (i.e. you can end up disturbing RF services other than wi-fi, possibly safety-critical services). https://www.everythingrf.com/community/what-is-p1db

=> Don't do that !

Harmonics. What safety critical stuff is at 4.8 GHz, 7.2 GHz, ...?

> But if you're running on the same channel as your neighbor, you're already asking for trouble.

This isn't true, WiFi handles same-channel interference better than off-channel interference. Especially newer standards have more tools to deal with it like BSS coloring.

PARP has entered the chat

Translated the linearity of your PA (nevermind LNA for RX) is unlikely to support even 20dBm, and the higher rate modulations for even 802.11a/g (nevermind any MIMO/SDMA workings) are EVM limited, not received power limited

It's peak-to-average power ratio (PAPR) or Crest factor [1].

It's not a really a big poblem for those who know, the limiting PA can be replaced or bypass with with more accommodating ones that can transmit higher power with better linearity and power envelope tracking.

[1] Crest factor:

https://en.wikipedia.org/wiki/Crest_factor

Yes, they only cost more and have greater power consumption

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