RE: 8b/10b and EMI
At 10:37 AM 0/3/16, Edward Chang wrote:
>
>I agree with you, no question about it. We have to watch the leak from the
>hole. The issue has been addressed by both transceiver vendors and
>equipment designers for quite a years as you know.
>
>The leak-from-hole issue at a gigabit rate has been resolved industry-wide,
>and I have not heard anyone complaining about that problem. Although it may
>surface again at 10 Gbps rate to seek for solution.
>
>However, the problem is not caused by a fiber, rather that is a fundamental
>EMI issue of leaking from a hole of an enclosure.>
Yes. All it takes is a small enough hole, and even 10 gbaud will be
confined. If the transmitter and receiver are correctly designed, the
photons will pass through a 1-mm or 2-mm diameter hole in a metal wall,
which will cut off everything below a few hundred gigahertz: (3*10^8
m/s)/(10^-3 m)= 3*10^11 Hz= 300 GHz.
Joe