Click Fraud
Oct
15
2015
9 Steps of Evolution of Fiber Networks – Step 2

<< Back to the Step 1

 

In previous post, about Step 1, where we discussed dawn of fiber communication links we saw, that main problems that engineers met at that time was distance limitations, and they needed add signal re-generators in middle of fiber distances, and needed thus convert back and forth signal from optical to electrical.

 
That was not effective and expensive.

 

What happened at Step 2 of this optical revolution? Optical Amplifiers were introduced, and schemes we discussed in previous post came to such concept:

 
Increasing optical transmission distance

 
Figure1 : Increasing transmission distance by introducing optical amplifiers.
 

Be sure to compare with schemes in Step 1.

 

So, what can clearly see here is that while technologically it was more complex, in reality scheme looks more simple now and these devices now starts to amplify signal  compensate power loss.

 

Another important thing is that these devices already does not needed convert signal back from optical to electrical. Examples of such devices are Raman amplifiers, EDFA’s, or Semiconductor Optical Amplifier.

 

Now testing is even more easy, it is enough to connect testing equipment at the end of those segments, where you need to compensate power loss value, and measure proper value.

 

However, it’s important to note, that while adding optical amplifiers compensates power lost, that is caused by attenuation, and can be also calculated if you know how many db you lose per km in your fiber cable, then optical amplifiers could not do anything with optical dispersion. This is why Dispersion Compensation Modules, or DCM’s where introduced along with Optical Amplifiers.
DCM’s can reduce the width of optical pulses transmitted into optical cable.

 

<< Back to the Step 1

Testimonials

Lomoveishiy – Finland

I needed those to connect my PC on the third floor to have internet access in that room, and ISP installed their modem on the first floor only. After dropping fiber patch cables, plugged in all cables into these media converters at both sides, and link came up instantly. Was much easier than I thought!

Raymond – USA

Great experience – units worked straight out of the box – just needed plug in cables and we were done. I also like the possibility to enable jumbo frames, while we do not have a need for this feature at the current moment it’s great to have this option.