Term
| Modal dispersion occurs in step index mutimode fiber where the paths of different modes are |
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Definition
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Term
| When used for telecommunications, cores are usually ____ with relatively ____ cladding. |
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Definition
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Term
| What are the two most important basic functions for optical networks? |
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Definition
- transmits information
- distributes information
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Term
| Total internal reflection means |
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Definition
| all of the light is confined to the core. |
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Term
| Which is NOT an electromagnetic wave? |
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Definition
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Term
| The first practical use of optical fibers was |
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Definition
| in bundles to examine the inside of the stomach. |
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Term
| The three main factors affecting the transmission of signals through a fiber are: |
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Definition
- attenuation
- dispersion
- crosstalk
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Term
| Two basic parts of a photoreceiver are |
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Definition
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Term
| The output of a 20km fiber with attenuation of .5 db/km is .005mW. The input power to the fiber is ____. |
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Definition
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Term
| What is the principal requirement for a cladding on an optical fiber? |
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Definition
| It must have a refractive index lower than the core to produce total internal reflection. |
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Term
| Fiber optic cables do not have problems with ____ like wire cables do. |
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Definition
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Term
| Advantages of optical fiber over wire are: |
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Definition
- capable of carrying high-bandwidth signals over much longer distances
- immune to electromagnetic interference
- fiber weighs less than wire
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Term
| "Critical angle" is defined as |
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Definition
| the least angle of indidence at which total internal reflection takes place. |
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Term
| Transmission of radiation through an optical fiber is the result of ____ ____. |
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Definition
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Term
| Optical fiber is described as a/an ____. |
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Definition
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Term
| Wavelength and frequency are ____ related. |
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Definition
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Term
| The operation of optical fiber is similar to a/an ____. |
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Definition
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Term
| "A particle with zero mass consisting of a quantum of electromagnetic radiation" is describing a/an ____. |
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Definition
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Term
| Light that passes from air to glass is ____. |
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Definition
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Term
What device is pictured below?
[image] |
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Definition
| LED (light emitting diode) |
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Term
| All fiber optic communication systems must include ____ ____, ____, and ____. |
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Definition
| light source, receiver, fiber |
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Term
| The two most important factors for determining the transmission medium are ____ and ____. |
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Definition
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Term
| Communications was defined as _____ of information. |
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Definition
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Term
| For what application is nonzero dispersion-shifted fiber required? |
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Definition
| Dense wavelength-division multiplexing around 1.55 micrometer. |
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Term
| LED's have advantages over LD's in the following ways: |
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Definition
higher reliability
better linearity
lower cost |
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Term
| The process by which two or more signals are transmitted over a single communications channel. |
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Definition
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Term
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Definition
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Term
| "The satellite is virtually motionless with respect to an observer on the ground" refers to what? |
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Definition
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Term
| Standard Single Mode Fiber (SSMF): |
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Definition
| is optimized for minimal dispersion in the 1310 NM band |
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Term
| LDs (Laser Diodes) have advantages over LED's in the following ways: |
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Definition
They produce greater optical power.
They can be modulated at very high speeds.
They have higher coupling efficiency to the fiber optic cable. |
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Term
| The carrier signal modulated to produce one optical channel in a fiber-optic system is a(an): |
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Definition
| Single wavelength of light generated in the transmitter. |
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Term
| A message is available to everyone connected to the system i.e., not just a point-to-point system. |
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Definition
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Term
| Basic features of an optical network: |
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Definition
Optical devices for switching
Optical devices for managing signals
Fiber optic transmission (using optical fiber as the medium). |
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Term
| The place where a telephone company switches signals in a community is a: |
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Definition
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Term
| ". . . . help to reduce unwanted signals by creating an induction current" refers to what? |
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Definition
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Term
What part of the telephone network is connected directly to your home telephone if you get your telephone
service from a local telephone company? |
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Definition
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Term
| For what application is nonzero dispersion-shifted fiber required? |
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Definition
| Dense wavelength-division multiplexing around 1.55 micrometer. |
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Term
The cutoff wavelength of a single-mode step-index fiber with core diameter of 8 micrometer, core index of 1.5,
and cladding index of 1.495 is _____ micrometers. |
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Definition
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Term
| Multimode fiber has a _____ bandwidth than single mode fiber. |
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Definition
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Term
| Time-division multiplexing of 8 signals at 150 Mbit/s each produces: |
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Definition
| One channel carrying 1.2 Gbit/s. |
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Term
| Single-polarization fiber transmit more modes than standard step-index single-mode fiber. |
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Definition
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Term
| A high-speed line or series of connections that forms a major pathway within a network. |
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Definition
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Term
The maximum allowable core diameter for a step-index single-mode fiber operating at 1.3 micrometer, with
core index of 1.5 and cladding index of 1.0003 (air) is _____ micrometer. |
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Definition
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Term
| Modal dispersion is largest in what type of fiber? |
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Definition
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Term
| Which of the following are true for digital signals? |
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Definition
They are transmitted in parts of the telephone network.
They can be processed electronically.
They can encode analog signals.
They are used in computer systems. |
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Term
You digitize a 10 kHz signal by sampling it at twice the highest frequency (i.e., 20,000 times a second) and
encoding the intensity in 8 bits. The resulting data rate is _____ kbit/s. |
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Definition
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Term
| Bandspace in which specific types of communications are to be transmitted. |
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Definition
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Term
The type of fiber that has little or no modal dispersion, modal noise, and other multimodal problems is a _____
type. |
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Definition
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Term
| What guides light in multimode graded-index fibers? |
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Definition
| Refraction in the region where core grades into the cladding |
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Term
Converting information into electrical/optical energy, sending it, and converting it back into its original form is
the basic operation of : |
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Definition
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Term
A fiber has modal dispersion of 20 ns/km. If an instantaneous light pulse traveled through 8 km of such fiber,
what would the pulse length be at the end? |
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Definition
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Term
The maximum allowable core diameter for a step-index single-mode fiber operating at 1.3 micrometer, with
core index of 1.5 and cladding index of 1.495 is _____ micrometer. |
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Definition
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