Light Emitting Diode (LED) Driving 10km Waveguide

[mogul28]

Homework Statement

A Light emitting diode (LED) drives a single mode waveguide that is 10 km long, and has a material dispersion of – 100 ps/km/nm for wavelengths near 800 nm. The LED radiation has a spectral width of 60 nm and is centered at 800 nm.

a) If the LED is pulsed on and off in 5 ns, what is the length of the optical pulse when it arrives at the end of the waveguide?
b) What is the maximum practical pulse rate for this system, if the received pulses are to be distinguishable from one another?

Homework Equations

The Attempt at a Solution

 

[SammyS]

Homework Statement

A Light emitting diode (LED) drives a single mode waveguide that is 10 km long, and has a material dispersion of – 100 ps/km/nm for wavelengths near 800 nm. The LED radiation has a spectral width of 60 nm and is centered at 800 nm.

a) If the LED is pulsed on and off in 5 ns, what is the length of the optical pulse when it arrives at the end of the waveguide?
b) What is the maximum practical pulse rate for this system, if the received pulses are to be distinguishable from one another?

Homework Equations

The Attempt at a Solution

What have you tried ?

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