Question

Why are noise considerations important in optical fiber communications? 3. Describe the principle of "population inversion".

Answer 1

Answer and Explanation:

the electronic devices always have some noises present in the signal

there are some important considerations in optical fiber communications these are.

• the noise which is contributed by transmitter are electronic random noise, low frequency noise
• noise which is contributed by laser are relative intensity noise, mode partition noise, conversion of phase noise to amplitude noise.
• noise contributed by photo detector are quantum shot noise, shot noise from dark current, avalanche multiplication noise.

PRINCIPLE OF POPULATION INVERSION :

The principle of population inversion is defined as for production of high percentage of simulated emission for a laser beam the number of atoms in higher state should be greater than lower energy state