Re: A question about learning 802.11

Hello,

On Tue, Aug 23, 2022 at 2:59 PM 吳恩緯 <rickywu0421@gmail.com> wrote:
> My question is, if I want to learn the work net80211 has to do to support modes like 802.11n/ac, do I need to know what exactly the physical layer has done? (I'm majoring in computer science, and I just want to write some codes to help net80211)

Generally speaking, you should not know too much about PHY for the
regular driver hacking. All PHY things are done by a chip and usually
you can not interfere with its work. All you need is chip
documentation, IEEE 802.11 standard knowledge and net80211 subsystem
concepts. All other PHY stuff you can assume as some kind of "magic".

But if you want to know exactly what you are doing, what is the
difference between MU-MIMO and OFDM-A or if you want to implement
something non-standard, then yes, it is better to have some signal
processing knowledge. Some knowledge of electronics is useful too,
especially when you have to deal with transmit power control or
receiver sensitivity.

Usually all this is a matter of time and wish. Just select a task,
start doing it, google unknown terms, and after a while you will
surprisingly realize that you know perfectly well what to do with all
these registers and knobs of a wireless chip. The road will be handled
by the walker. While the study + practice mix is a good way to walk.

Or as I said before, just consider it "magic" and you will be a happy
developer too if it is okay for you to work with "magic" :) Anyway you
can not "inspire" a 802.11n chip to support the 802.11ax frame format
:)

-- 
Sergey