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Re: LH/ELH Recommendations?


From: Mikael Abrahamsson <swmike () swm pp se>
Date: Fri, 30 May 2003 00:07:28 +0200 (CEST)


On Thu, 29 May 2003, N. Richard Solis wrote:

effects of high laser power on glass fibers.  At last guess, that limit
was about +17dBm into standard SMF-28.  Couple this with a typical
receive sensitivity of -12dBm for 10gpbs signals and you've for about
29dB of link margin to work with.  Assuming of course that there aren't

Interesting. I have GigE stuff that have a receive sensitivity of -29dB, 
if we could launch with +17dB somehow (this equipment only launches with 
typical +4dB), things would get interesting.

With a .2 dB per km (I have seen this on newer fiber) that'll actually put
the length of fiber into the 200+km territory (230km according to my
math). Still, it's not 200 miles, and the amp to amplify +5 into +17 would
not be cheap, probably at least 10 times more expensive than a regen/amp
to put in the middle to go from -29 into +5 again.

-- 
Mikael Abrahamsson    email: swmike () swm pp se


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