Completion Complete each statement.
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1.
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This is The FOA Online Design Self-Study Program
Case Study No. 3.
This exercise covers the design of a Long Distance Telecom Network
A
medium sized town is connecting to an adjacent town with fiber optics.
Basic System Information: The total fiber/cable distance is 80 km. The link has
several segments. Within each city, cable is pulled underground in existing ducts, but between the
cites, it is direct buried underground. All links are fusion spliced at 16 different points, plus 2
pigtails are spliced on the ends for termination. The system will be transmitting at OC-192
speeds (10 Gb/s) and will be using DWDM for maximum fiber utilization. Upgrades to higher rates (~100
Gb/s) are planned in the future.
Please enter your name, CFOT/Membership number and date
to begin this exercise.
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Multiple Choice Identify the choice that best
completes the statement or answers the question.
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2.
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The system will be transmitting at OC-192 speeds
(10 Gb/s) and will be using DWDM for maximum fiber utilization.
What will be the wavelength
used for transmission?
A. | 1310 nm | B. | 1490 nm | C. | 1550
nm | D. | 1310 and 1550 nm |
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3.
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Which one of the following fibers is the best
choice for this network?
A. | ITU G.652 - single-mode NDSF
(non-dispersion-shifted fiber) | B. | ITU G.653 -
single-mode dispersion-shifted optical fiber | C. | ITU G.654single-mode fiber which has the zero-dispersion wavelength around
1300 m wavelength | D. | ITU
G.655single-mode NZ-DSF (nonzero dispersion-shifted) fiber), optimized for WDM and
long-distance cable runs |
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4.
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The cable chosen for the metropolitan sections of
the link is a loose-tube design because the cable must be _____.
A. | Water-blocked and armored | B. | Water-blocked and rated for high pulling tension | C. | Rated for aerial installation without a messenger | D. | UL Listed for flame retardance |
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5.
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The cable chosen for the rural section between the
cities should be a loose-tube design and must be _____.
A. | Water-blocked and armored | B. | Water-blocked and rated for high pulling tension | C. | Rated for aerial installation without a messenger | D. | UL Listed for flame retardance |
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6.
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How many fibers should be in the
cable?
A. | As few as possible to reduce cable size and
weight | B. | As few as possible to reduce cable and splicing
cost | C. | As many as possible to allow maximum flexibility and
upgrades | D. | Only as many as
needed |
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7.
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In order to ensure the system will work on the
cable plant being designed, it is necessary to have what information on the communication system
intended for use on the cable plant?
A. | Wavelength | B. | Transmitter min/max power output | C. | Receiver min/max input powers | D. | All of the above |
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Typical Specifications Provided for use
as case studies for design labs in FOA courses.
Component
Specifications | | | Fiber Loss | | Singlemode at 1310 nm | 0.4 dB/km (TIA 568: 1 dB/km) | Singlemode at 1550 nm | 0.25 dB/km | | | Splice Loss | (TIA 568: 0.3 dB, all
types) | Singlemode, fusion | 0.05 dB | Singlemode,
mechanical | 0.3 dB | | | Connector Loss | (TIA 568: 0.75 dB, all
types) | Singlemode, adhesive/polish | 0.3 dB | | |
Active Device and System
Specifications | | | Digital Transceiver Specs1 | Power (dBm), T=transmit, R=receive | 1310 laser (>1
Gb/s) | T: +3 to -3 dBm, R: -10 > -25 | 1550 laser (>1
Gb/s) | T: +3 to -3 dBm, R: -10 > -25 | Fiber
Amplifier | Gain +17 dB | DWDM Module Loss
#channels/dB | 8 ch/4 dB, 16 ch/5dB, 32 ch/6 dB | | |
Link margin specifications for most standardized fiber optic networks are
on the FOA Tech Topics Site (http://www.thefoa.org/tech/Linkspec.htm). It should be used as a
reference for designers and for the courses.
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8.
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Using the information supplied, calculate the cable
plant loss budget for this link. Use the infomation in the "Typical Specifications"
narrative above.
A. | 21.50 dB | B. | 33.50 dB | C. | 22.40
dB | D. | 26.00 dB |
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9.
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For the equipment listed above, will the system
operate on this cable plant?
A. | Yes | B. | Yes, but may require an attenuator at the transmitter
end | C. | Yes, bmay require an attenuator at the receiver
end | D. | No, it cannot work under any
circumstances |
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Multiple Response Identify one or more choices
that best complete the statement or answer the question.
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10.
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What parameters should be tested and documented to
confirm proper installation?
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11.
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Testing of each fiber should be done as follows:
(Choose all the correct answers)
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12.
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If the intercity links were to be installed
aerially, what are the options for cable installation?
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13.
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What should be included in the design documents to
have the customer prepare for restoration in case of an outage?
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