Fiber Flashcards
These two scientific properties allow light to travel inside of a specialized piece of glass know as fiber optics:
Refraction, Reflection
These active devices must be changed when transitioning a network fro sub-split to mid-split:
Amplifiers
To take full advantage of DOCSIS 3.1 upstream speeds, Comcast network needs to adopt this architecture:
High-Split
The history of of Fiber Optics goes back to as early as this:
1700’s
In this decade, Fiber Optic cable was improved and gained the capability to transmit light over long distances:
1960’s
In this year, John Tyndall demonstrate that light could be channeled through a curved stream of water:
1854
This individual first demonstrated that light could be channeled through a curved medium;
John Tyndall
This a process that confines light to an optical fiber:
TIR (Total Internal Reflection)
This process is the reflection of the total amount of incident light that occurs with large angles of incidence:
Total Internal Reflection - TIR
Light can travel through a stream of water and remain contained because air and water because this characteristic differs:
Index of Refraction
Light propagates inside the core of a fiber by this:
TIR Total Internal Reflection
This is the glass covering over the core of a fiber optic cable
Cladding
IoR
Index of Refraction
This term describes the imaginary line running perpendicular to the interface of of two materials:
The Normal
This is the angle between the incident ray and the normal:
The angle of Incidence
This is the angle between the refracted ray and the normal:
The angle of Refraction
Light traveling inside the core of a fiber optic cable strikes the cladding at this angle:
The angle of incidence
In order for fiber optic cable to cause TIR, This component is more dense than the cladding:
Core
These are the 4 types of dispersion in fiber optic signal:
Modal, Chromatic, Waveguide, polarization-mode
During process of manufacturing fiber optic cables, the process used to thicken the core of the fiber by adding a mixture of elements can cause this:
Intrinsic Loss
This is the spreading in time of an optical signal as it travels down the length of an optical fiber:
Dispersion
This form of dispersion is the most common in multimode-fiber optic systems:
Modal Dispersion
This is when the core of multimode fiber allows light to break up into many different “modes” or paths, with some modes reaching the far end of an optical fiber before others:
Modal Dispersion
This results from different wavelengths traveling through a fiber at different velocities, the intensity increases as the distance increases:
Chromatic Dispersion
This occurs because small amounts of light travels in the interface between the core and cladding:
Waveguide Dispersion
Light can be broken into a vertically polarized component and a horizontally polarized component. This occurs when these components travel through a optical fiber at different velocities:
Polarization-Mode Dispersion
Imperfections and impurities in optical fibers caused when making the structure of fiber will cause signal loss in these two forms:
Scattering and Absorption
This comes from changes in the density of a optical fiber and variations of the composition that occur during manufacturing:
Rayleigh Scattering or Double Rayleigh Scattering
These two optical wavelengths are used in the cable industry are because they are less affected by absorption than their neighbors on the spectrum:
1310nm and 1550nm
This is the term for signal loss inside fiber that is the result of installation methods:
Extrinsic Loss
This is when a fiber optic cable is visibly bent too sharply and will cause some of the light to hit the interface between the core and cladding that exceeds the critical angle:
Macrobend
This is a small irregularity in the core-to-cladding interface that cause reflections that allow the light to be refracted out of the core:
Microbend
In an HFC network with multiple active devices, a power supply along with a power inserter is used to introduce these two possible voltage levels into the hardline coax:
60 or 90 V
All Fiber Deep Designs must meet the max power consumption of this per fully configured node:
160 Watts
Each Fiber Deep node must have a minimum voltage of this :
50 V
This is a hardline coax connection that will bring AC power from one segment to another:
Power Bus
Power inserters have this many ports
3
This device connects the power supply to the hardline cable to power all the active devices:
Power inserter
This is the act of pulling power from one segment to provide power to another segment:
Power Bus
extends an uncontaminated section of cleaning material from the nozzle of the tool using an automatic reeling system
One Click
contains a powerful solvent cleaner that quickly and safely cleans the end face of fiber optic connectors, splices and ribbons.
Electro Wash Optic Cleaning Pen
A cassette style fiber optic connector cleaner system that use densely woven micro-fiber cleaning fabrics to remove harmful contaminants off of the ferrule end face
CLETOP
first step for installer measurement procedures should also start with inspection and verification of the cleanliness of the connectors and ports.
Fiber Inspection (Scope)
accurately measures optical power at simultaneous wavelengths, supporting measurements over burst mode transmissions.
Pon Power Meter or PPM
It can verify splice loss, measure length and find faults in fiber cable.
Optical Time Domain Reflectometer (OTDR)
The card will quickly visually indicate if an IR LED is producing light
Fiber Detector Card
Connects the OTDR to the link-under-test, discloses the insertion loss and reflectance of the near-end connection
OTDR launch cable
important in order to ensure the reliability and functionality of the final link
Proper cleaning of optical fiber
two methods of cleaning optical fiber
Wet and dry
Isopropyl alcohol purity %
0.9
Used to clean fiber in wet method
Lint free wipes, Isopropyl alcohol, lint free swabs or urethane foam heads
minimum magnification required for proper inspection to the degree needed for longer wavelength optical signals such as 1550 nm
400x
amount of slots a dry cleaner has with a cleaning tape underneath
2
Another method used to dry clean fiber
push pen
if not performed properly, can leave alcohol residue.
use of alcohol and lint-free wipes
What device will take the incoming coming fiber from the headend or hub site and distribute it to within 1000 feet from the customer?
Multiplexing Point
means by which light from an optical source is directed to a destination
optical fiber
Three basic components of optical fiber
Core, cladding, protective cover
Fiber with a large core that supports more than one mode
multimode fiber
Causes high loss by allowing light to escape from the core into the cladding of the fiber
Macrobend
Tool used to identify a macrobend by launching visible light down the optical fiber
Visual Fault Locator (VFL)
Name 3 of the 6 components of an optical fiber cable
Optical fiber, Buffer tube, Strength member, Water blocking elements, Armor, Jacket
A typical fiber bundle contains how many fibers
12
this device takes information in electrical form and encode that information onto an optical signal
Optical transmitters
two basic methods of encoding information onto an optical signal by varying the intensity of the light
baseband digital modulation and analog intensity modulation (AIM)
diretly encodes digital 1’s and 0’s as pulses of light
baseband digital modulation
varying the intensity of the light in direct proportion to the analog electrical signal that is applied to the optical transmitter
anilog intensity modulation
