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Message-ID: <b578b872537a28762593dd4695aab2968d5b3fcc.camel@sipsolutions.net>
Subject: Re: Simulate Radio wave interference
From:   Johannes Berg <johannes@sipsolutions.net>
To:     Masashi Honma <masashi.honma@gmail.com>
Cc:     linux-wireless@vger.kernel.org
Date:   Tue, 24 Mar 2020 13:36:52 +0100
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Hi,

>  > I think from a timing aspect, checking if two signals are in phase will
>  > be practically impossible - we're talking about less than 1us timing
>  > differences (0.2 at 5 GHz), if I'm doing the math correctly?
> 
> I do not mean just in phase or opposite phase. Of course it could not
> be happened in real world.
> 
> I mean two or more radio waves composes a mixed wave.
> 
> Refer attached pictures.

Sure, but that's even worse? You need significantly less than
microsecond granularity to take this effect into account, and then you'd
have to probably also take distance into account for propagation time
etc.?

Anyway, I don't have a problem with the old model and don't have a need
for a different (even if perhaps better) one. Really what I'm mostly
thinking about is the MAC vs. air stuff, see my other email.

johannes