Optical Fiber Characteristics Flashcards
What are the different paths light can take called?
Modes
What affect will bending the fiber optic cable have on the tensile strength?
Decreases the tensile strength
What are the three types of modes?
High-order, low-order and zero-order mode
What is the main problem that affects multimode step index fiber?
Modal dispersion
What is modal dispersion?
High and low order modes move slower than zero order modes.
What type of fiber can be used to combat modal dispersion?
Graded-index fiber
How does graded-index fiber combat modal dispersion?
Gradually speeds up and slows down high and low order modes to match the zero order mode
Why is modal dispersion not a problem in single mode fiber?
There is only one mode
What is dispersion?
The spreading of light as it moves away from the source
What are the five types of dispersion?
Modal, material, waveguide, chromatic, polarization
What are the methods that can be used to reduce modal dispersion?
Graded-index fiber, increase the bit rate, reduce the core size, increase the wavelength
What is the information carrying capacity of fiber called?
Bandwidth
What is attenuation?
Signal loss expressed in decibels (dB)
As wavelength increases what happens to attenuation?
It decreases
What are two types of attenuation?
Intrinsic and extrinsic
