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LED vs. Laser Light Source / OM4 Multi Mode Fiber Optic Cable Attenuation

LED vs. Laser Light Source / OM4 Multi Mode Fiber Optic Cable Attenuation

I have an application involving a 1,200 foot run of OM4 laser optimized 50/125 um multi mode fiber optic cable. I have a new device that needs to communicate over this fiber link, but it only comes with a LED light source. Specs for new device are:

Light Source: LED
Data Rate: 100 Mbps
Wavelength: 1300 nm
Multimode: 62.5 um
Optical Budget: 11 dBm
Max. Distance: 2 km

Since I will be using 50 um multi mode cable with a LED light source, how do I determine the maximum distance based on above specs?

I have attenuation data for both 50/125 and 62.5/125 um multi mode cable, but I cannot figure out detailed impact of using LED vs. Laser light source.

RE: LED vs. Laser Light Source / OM4 Multi Mode Fiber Optic Cable Attenuation

Not sure what the issue is. You have a 1200 ft run and a source capable of driving 2 km, which is 6561 ft, so you would seem to have plenty of margin.

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RE: LED vs. Laser Light Source / OM4 Multi Mode Fiber Optic Cable Attenuation

OM4 is a higher quality fiber and is backwards compatible to lower LED bandwidth cables (OM1 & OM2) so you should not have any problems with using OM4 fiber. Corning recommends the use of OM3 or OM4 (50u) for all legacy systems so you should be fine. But, to be sure you should contact the manufacturer of the device and confirm with them.

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