Transmission in Optical Fiber Communication

8/12/2019 Transmission in Optical Fiber Communication

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CONTENTS

1. FUNDAMENTAL OF OPTICAL FIBER ………………………...…1-19

1.1 Introduction …………………………………………...………….21.2 Definition of optical fiber ……………………………………....31.3 Principle of operation an optical fiber …………………….…41.4 Basic fiber optic cable theory and technology ...............…....41.5 Laser light sources ...........................................................…...41.6 Wavelengths ………………………………………….…….……..51.7 Frequency and wavelength ……………………………….….…..51.8 Optical Power ……………………………………………...…….…6 1.9 Refraction and Reflection …………………………...……….…61.10 Optical fiber construction ……………………………...…….…8

1.11 Bends ………………………………………………………….…...81.12 Modes and modal dispersion …………………………….………...91.13 Types of optical fiber ……………………………………….….…101.14 Types of cable …………………………………………….…….…19 1.15 Losses of optical fiber …………………………………………..…..171.16 Amplifiers signal conditioning elements in an optical network ...191.17 Dense wavelength division multiplexing ………………..……19

2. TRANSMISSION OF OPTICAL FIBER COMMUNICATION ………..20-23

2.1 Introduction of optical fiber communication ……………………..21

2.2 Definition of transmission ……………………………………..212.3 Types telecommunications transmission …………………..…222.4 Definition of optical fiber communication …………………..…222.5 Block diagram of optical fiber communication ………...…...23

3. PLANNING OF OPTICAL FIBER TRANSMISSION …………24-27

3.1 Planning …………………………………………………..……..…..253.2 Route survey …………………………………………………..…253.3 Work flow chart …………………………………………………..…263.4 Route survey summary report from ………………………..…....27

4. DUCT HANDLING STORAGE AND DUCT LAYING …………28- 51

4.1 Definition of duct ……………………………………………..29



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4.2 Advantages of using high density polyethylene (HDP) ducts …294.3 Duct transportation ……………………………………………..304.4 Method of Loading & unloading for HDP ducts ……….…….314.5 Duct storage ……………………………………………………..34

4.6 Trenching ……………………………………………………..354.7 Duct mounting steel reels ………………………………..……354.8 Duct laying …………………………………………………..…374.9 Duct Integrity test procedure ………………………………….….414.10 Types of duct Integrity test ………………………………….….464.11. Safety for duct Integrity test ……………………………………..514.12 Milestone and fractional milestone number ……………………..51

5 CABLE PULLING AND JETTING ………………………….……..52- 60

5.1 Definition cable pulling …………………………………………..…53

5.2 Definition cable jetting …………………………………………..…535.3 Advantages of Cable jetting ………………………………….… 535.4 Block diagram of cable jetting system ………………..…...545.5 Determine the cable size due to duct size ………………….….545.6 Compressor ……………………………………………………..555.7 Types of cable Jetting machine …………………..…………555.8 Advantages of cable jet machine compared with super jet ….....565.9 The performance of the cable jet system …………………….…..575.10 Jetting efficiency …………………………………………………..…575.11 Prerequisites for cable blowing ……………………………..585.12 Pre-blowing Activities …………………………………………..…58

5.13 Distribution of Jobs ………………………………………..……585.14 Salient points during cable blowing ……………………….…….60

6. OPERATION AND MAINTENANCE ………………………………....61-70

6.1 List of used tools ……………………………………………..626.2 Junction in fiber optic cable ………………………………….….656.3 Termination of optical fiber cable ………………………….….706.4 Optical distribution frame ……………………………………..70

7. DISCURSION AND CONCLUSION ………………………………..……71

8. REFFRENCE …………………………………………………………..…72



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FUNDAMENTAL OF OPTICAL FIBER

1.1 Introduction

The transmission of light via a dielectric waveguide structure was firstproposed and investigated at the beginning of’ the twentieth century. In 1910



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Hondros End Debye conducted a theoretical study, and experimental workwas reported by Scbrjever in 1920. However, a transparent dielectric rod,typically of silica glass with a refractive index of around 1.5, surrounded byair, proved to be an impractical waveguide due to its unsupporte4.Structure

(especially when very, thin waveguides were considered in order to limit thenumber of optical modes propagated) add the excessive losses at anydiscontinuities of he glass air interface. Nevertheless, interest in theapplication of dielectric optical waveguides in such areas as optical imagingand medical diagnosis (e.g endoscopes) led to proposals for a clad dielectricrod in the mid-1950s in order to overcome these problems.

Figure Optical fiber waveguide showing the core of refractive index n1,surrounded by the cladding of slightly lower refractive index n2.

Transparent core with a refractive index in surrounded by a transparentcladding ofSlightly lower refractive index n2. The cladding supports the waveguidestructure whilst also, when sufficiently thick, substantial reducing theradiation loss into

the surrounding air. In essence, the light energy travels in both the core andthe cladding allowing the associated fields to decay to a negligible value atthe cladding air interface.

The invention of the clad waveguide structure led to the first seriousproposals by Kao and Hockham and \Vats [Ref. 61, in 1966, to utilize opticalfibers as a communications medium, even though they had losses in excessof 1000 dB km-1. These proposals stimulated tremendous efforts to reducethe attenuation by purification of the materials. This has resulted in improvedconventional glass refining techniques giving fiber with losses of around 4.2dB km-1. Also, progress in glass refining processes such as depositing

vapor-phase reagents to form silica has allowed fibers with losses below 1dB km-1 to be fabricated.Most of this work was focused on the 08 to 0.9 µm wavelength bandbecause the first generation optical sources fabricated from galliumaluminum arsenide alloys operated in this region. However, as silica fiberswere studied in further detail it became apparent that transmission at longerwavelengths (1.1 to 1.6 µm) would reu1t in lower losses and reduced signaldispersion. This produced a shift in d’ optical fiber source and detector

n1

n2 Claddin

Core

Fig. : Optical fiber



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technology in order to provide operation at these longer Wavelengths,Hence at longer wavelengths, especially ‘around 1.55 µm, fibers with lossesas low as 0.2 dB km-1 have been reported.

Such losses, however, are very close to the theoretical lower limit for silicateglass fiber and, ‘more recently, interest has grown in glass forming systemswhich can provide low loss transmission in the mid. infrared (2 to 5 µm) andalso the far- infrared (8 to 12 µm) optical wavelength regions. At present thebest developed ofthese systems which offers the potential for ultra-low-loss transmission ofaround 0.01 dB km-1 at a wavelength of 2.55 µm is based on fluoride glass.

In order to appreciate the transmission mechanism of optical fibers withdimensions approximating to those of a human hair, it is necessary toconsider the optical wave guiding of a cylindrical glass fiber. Such a fiber

acts as an open optical waveguide, which may be analyzed utilizing simpleray theory However, the concepts geometric optics are not sufficient whenconsidering all types of optical fiber, and electromagnetic mode theory mustbe used to give a template picture.

1.2 Definition of Optical f iber

Optical fiber (or "fiber optic") refers to the medium and the technologyassociated with the transmission of information as light pulses along a glassor plastic strand or fiber. Optical fiber carries much more information thanconventional copper wire and is in general not subject to electromagnetic

interference and the need to retransmit signals. Most telephone companylong-distance lines are now made of optical fiber. Transmission over anoptical fiber cable requires repeaters at distance intervals. The glass fiberrequires more protection within an outer cable than copper. For thesereasons and because the installation of any new cabling is labor-intensive,few communities have installed optical fiber cables from the phonecompany's branch office to local customers (known as local loops). A type offiber known as single mode fiber is used for longer distances; multimodefiber is used for shorter distances.

1.3 Principle of operation an optical fiber

An optical fiber is a cylindrical dielectric waveguide that transmits light alongits axis, by the process of total internal reflection. The fiber consists of a core surrounded by a cladding layer. To confine the optical signal in the core, therefractive index of the core must be greater than that of the cladding. The



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boundary between the core and cladding may either be abrupt, in step-indexfiber , or gradual, in graded-index fiber .

1.4 Basic Fiber Optic Cable Theory and Technology

Many of today’s communication networks use fiber optic links to carry voice,video and data information at the speed of light. Fiber optic links incorporatemultiple transparent glass or plastic fiber cables that guide modulated lightwaves through the network. In digital systems, message data is convertedinto a series of binary digits that are used to switch the light source on andoff, creating a sequence of coded light pulses.

A receiver at the other end of the cable decodes the light pulses back intodigital ones and zeroes to reconstruct the original message data. Thissection describes some of the basic characteristics of fiber optic cable and

its use in communications networks.

1.5 Laser Light Sources

Most fiber optic communication networks use lasers as light sources. A laseris a device that creates a narrow, intense beam of coherent light - at a singleor just a few frequencies going in one precise direction. The word laser is anacronym for light amplification by stimulated emission of radiation. Lasers

are described by their wavelength in nanometers (nm) and by their outputpower levels.1.6 Wavelengths

Three laser wavelengths are currently in use for fiber optic systems: 850 nm,1310 nm and 1550 mm all three wavelengths are in the infrared spectrumand are invisible to the human eye (see Figure).



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The distances between network nodes and the number of connectionsdetermine the best selection of fiber type and laser wavelength. As a rule ofthumb:

• Lasers with longer wavelengths can transmit over greater distances.• Lasers with longer wavelengths cost more than lasers with shorterwavelengths.

• Long distance systems using higher bandwidth single mode fiber requiremore expensive connectors.

1.7 Frequency and Wavelength

Electromagnetic waves can be described m terms of their wavelength orfrequency, which are mathematically related. Wavelength, also referred toas “lambda”, or “A.”, is the distance of one complete cycle of a periodicsignal frequency. Frequency is the number of complete cycles that occur perunit of time. Wavelength is measured in meters, frequency in cycles persecond (called Hertz).

We traditionally describe radio signals by their frequency (from about 1kilohertz to 1 megahertz) and visible light waves by their wavelength (400nanometers to 700 nanometers). A nanometer is equal to 10-9 (1 billionth)of a meter. Fiber optic systems use light sources with wavelengths in theinfra-red part of the electromagnetic spectrum.

1.8 Optical Power



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The power (or brightness) of a laser determines how far a signal can be sentdown a fiber and how much risk for eye damage it represents. Lasers arcdivided into three power classes:

• Class I lasers are inherently safe and will not cause damage to the humaneye.• Class II lasers have higher power output that can cause eye damage withexposure of more than three seconds.• Class III lasers have the highest power output. They are inherentlydangerous and require eye protection and other safeguards.Most telecommunications systems use Class I lasers; Visual Fault Findersand some optical amplifiers use Class II. Most test equipment, includingOTDR’s, use Class I.

It is advised: Never look directly into any operating laser or lit fiber. Laser

light can cause eye damage or blindness.

1.9 Refraction and Reflection

The speed of light is determined by the medium in which it is traveling. Theindex of refraction (ir) for a material is expressed as the ratio of the speed oflight in a vacuum (c)to the speed of light in the material (v), where ir = c/v. Values of ir areapproximately1.333 for water, 1.473 for glycerin and 2.417 for diamond. In fiber opticglass, the index of refraction ranges from 1.46 to 1.6. Light waves bend

(refract) or bounce (reflect) when they meet the boundary between twomaterials with different indices of refraction.

The angle at which the light strikes the boundary affects the amount and

direction of light that is refracted and/or reflected. Figure illustrates a familiarexample of light at the boundary of air and water.



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Angles of refraction and reflection vary according to the wavelength of thelight source. We see the results of this property in a prism as it separates

sunlight into its component colors and in a rainbow where light is refracted,by raindrops into an orderly sequence of colors from violet to red— each ata different angle.

Light reflected from a glass-air boundary is called a fresnel (pronouncedfresnel), reflection. The detection of fresnel reflections can be very usefulwhen testing fibers because they reveal the glass-air boundaries at the endsof fibers and at junctions such as connectors and mechanical splices.

1.10 Optical Fiber Construct ion

An optical fiber consists of a thin strand of glass or plastic (“core”)surrounded by glass or plastic “cladding” material that contains and reflectslight down the center of its core with minimum attenuation. The index ofrefraction of the cladding is different from that of the core in order to containthe light waves within the fiber - an effect known as total internal reflection.Most fibers are covered with buffer coatings and/or jackets to protect themfrom moisture and damage.



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Figure 4 shows the construction of a typical telecommunications singlemode optical fiber. The fiber consists of:Core: The light-carrying core of an optical fiber is made of glass with atypical index ofrefraction of 1.47.Cladding: The cladding is also made of glass and surrounds the core.Buffer: The buffer is a shock-absorbing protective covering, made of apolymer such asKevlar, to protect the core and cladding from damage.

1.11 Bends

Optical fiber has great lateral strength and it can be stretched significantlywithout problems. Unfortunately, it is susceptible to failure when it is bent,leading to unpredictable system outages. Bends or kinks in the fiber createcross-sectional stress points that can separate into breaks over time orcreate excessive loss with drops in temperature, especially at longerwavelengths.Bends can be created during installation, caused by unintended twists in thecable or by external objects (like rocks) impacting the cable when it isburied. They can also occur at termination or splice points where fiber may

be spooled with too small a radius or bent around objects after leaving thecable sheath. The risk of negative effects from bends increases with coldertemperatures and when the external line is physically stressed.



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When light strikes the boundary between the core and the cladding, it either

reflects and travels down the core or refracts and escapes from the core. Aslong as it is used within its specifications, fiber can be bent and flexedwithout losing much light, as illustrated in Figure .The small size and round shape core causes most of the light to strike theboundary at a small angle and reflect down the core with very little of thelight escaping. The fiber transmits light as long as the tubular shape of thefiber is not distorted; however, light will escape if the fiber is cracked, kinkedor bent below its specified minimum radius.

1.12 Modes and Modal Dispersion

Light traveling down the core of the fiber can follow one or more paths or“modes” depending on the diameter of the fiber. There are two categories offiber used in communications systems — single mode and multimode. Glasscores are used in both types; although some new plastic-core multimodecables promise performance for very short runs similar to glass and at alower cost

1.13 Types of Optical fiber

1.13.1 Depend on mode

1.13.1.1 Step index fiber (single-mode)



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In step index fibers, the core and the cladding have a different index ofrefraction. Single- mode fibers have a very small core diameter (< 9 µm).This allows only one single mode (wave propagation) to pass through the

fiber. Such fibers have very small attenuation andlarge bandwidth (> 10 GHz.km), no pulse broadening, no transit timedifferences. Typically used: 9/125 µm fibers at 1300 nm for long distances.

1.13.1.2 Step index fiber (multimode)

Multimode fibers have a fairly large diameter (> 100 µm). This allowsmultiple modes to pass. Such fibers have higher attenuation and smallbandwidth (< 100 MHz.km) strong pulse broadening and transit timedifferences. Typically used for LAN applications (< 300 m).

1.13.1.3 Graded index fiber (mul timode)



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In a graded index fiber, the index of refraction gradually changes from coreto cladding. Such fibers have small transit time differences and small pulse

broadening, small attenuation, and bandwidth < 1 GHzkm. Typically used:50/125 µm or 62.5/125 pm fibers for short distances (<500 m).

1.13.1.4 Single mode fiber

Single mode fiber is a single strand of glass fiber with a relatively narrowdiameter (nominally 9 microns), through which only one mode willpropagate. The small core and single light wave virtually eliminate- anydistortion that could result from overlapping light pulses, providing the leastsignal attenuation and the highest transmission speeds of any type of fiber

cable.

Single mode fiber carries higher bandwidth and lower spectral dispersionthan multimode and requires a light source with a narrow spectral width. Itsupports a higher transmission rate and up to 50 times more distance thanmultimode. However, single mode connectorsand splices have very little tolerance for core misalignment, making themsignificantly more expensive to manufacture and install. Single mode fibersoperate at wavelengths from 1300 to 1550 nanometers and are usedprimarily for telecommunications and CATV applications.1.13.1.5 Multimode fiber

Multimode fiber provides high bandwidth at high speeds over shortdistances. Typical multimode fiber core diameters are 50, 62.5, and 100micrometers and operate with light source wavelengths from 850 to 1300nanometers. Although multiple paths can become an undesired effect, thelarger core permits the use of less expensive connectors and allows lesscritical tolerances for manufacturing and installing the connectors.



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Multimode cable is usually preferred in systems such as Local AreaNetworks (LAN’s) that incorporate many connectors with short fiber runs. Incable runs greater than 3000 feet (914 meters), the multiple paths of lightcan cause signal distortion at the receiving end, resulting in an unclear andincomplete data transmission.Modal dispersion is the result of a light pulse being spread out over time

because it has traveled multiple paths simultaneously, as in a multimodefiber. Multiple path dispersion own cause events to blend into one another oreliminate some events altogether. An important consideration for multimodecable is its bandwidth versus length specification. For example, a cablespecified at 100 MB/s for a 1 kilometer link would carry 200 MB/s over a 0.5km link, or 50 MB/s in a 2 km link. Therefore, multimode links are bandwidthlimited to prevent data points from getting too close together and being lost.This bandwidth limitation is acceptable for many LAN applications but not forhigh-speed links between major systems.

1.13.2 Types of Optical fiber depend on ITU

This section discusses various MMF and SMF types currently used forpremise, metro, aerial, submarine, and long-haul applications. TheInternational Telecommunication Union (ITU-T), which is a globalstandardization body for telecommunication systems and vendors, hasstandardized various fiber types. These include the. 50/125-pm gradedindex fiber (0.65 1), Nondispersion-shifted fiber (0.652), dispersion-shiftedfiber (0.653), 1550-nm loss-minimized fiber (0.654), and NZDSF (0.655).



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the attenuation is minimum. The DSFs are optimized for operating in theregion between 1500 to 1600 nm. With the introduction of WDM systems,however, channels allocated near 1550 rim in DSF are seriously affected bynoise induced as a result of nonlinear effects caused by FWM. This initiated

the development of NZDSF. 0.653 fiber is rarely deployed any more and hasbeen superseded by 0.655.

1.13.2.5 1550-nm Loss-Minimized Fiber (JTU-T G.654)

The ITU-T 0.654 fiber is optimized for operation in the 1500-nm to 1600-nmregion. This fiber has a low loss in the 1 550-nm band. Low loss is achievedby using a pure silica core. ITU-T 0.654 fibers can handle higher powerlevels and have a larger core area. These fibers have a high chromaticdispersion at 1550 nm. The ITU 0.654 fiber has been designed for extendedlong-haul undersea applications.

1.13.2.6 Nonzero Dispersion Shifted Fiber (JTUT G.655)

Using nonzero dispersion-shifted fiber (NZDSF) can mitigate nonlinearcharacteristics. NZDSF fiber overcomes these effects by moving the zero-dispersion wavelength outside the 1550-nm operating window. The practicaleffect of this is to have a small but finite amount of chromatic dispersion at1550 rim, which minimizes nonlinear effects, such as FWM, SPM, and XPM,which are seen in the dense wavelength-division multiplexed (DWDM)systems without the need for costly dispersion compensation. There are twofiber families called nonzero dispersion (NZD+ and. NZD—), in which the

zero-dispersion value falls before and after the 1550-nm wavelength,respectively. The typical chromatic dispersion for 0.655 fiber at 1550 nm is4.5 ps/mm-km. The attenuation parameter for 0.655 fiber is typically 0.2dB/km at 1550 nm, and the PMD parameter is less than 0.1 ps/ km. TheCorning LEAF fiber is an example of an enhanced 0.655 fiber with a 32percent larger effective area.

1.14 Types of cable

1.14.1 Simplex and Zip Cord:

Simplex cables are one fiber, tight-buffered (coated with a 900 micronbuffer over the primary buffer coating) with Kevlar (aramid fiber) strengthmembers and jacketed for indoor use. The jacket is usually 3mm (1/8 in.)diameter. Zipcord is simply two of these joined with a thin web. It’s used



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mostly for patch cord and backplane applications, but zipcord can also beused for desktop connections.

1.14.2 Distribution Cables:

They contain several tight-buffered fibers bundled under the same jacketwith Kevlar strength members and sometimes fiberglass rod reinforcementto stiffen the cable and prevent kinking. These cables are small in size, andused for short, dry conduit runs, riser and plenum applications. The fibersare double buffered and can be directly terminated, but because their fibersare not individually reinforced, these cables need to be broken out with a“breakout box” or terminated inside a patch panel or junction box.

1.14.3 Breakout Cables:

They are made of several simplex cables bundled together. This is a strong,rugged design, but is larger and more expensive than the distribution cables.It is suitable for conduit runs, riser and plenum applications. Because eachfiber is individually reinforced, this design allows for quick termination toconnectors and does not require, patch panels or boxes. Breakout cable canbe more economic where fiber count isn’t too large and distances too long,because is requires so much less labor to terminate.

1.14.4 Loose Tube Cables:

These cables arc composed of several fibers together inside a small plastic

tube, which are in turn wound around a central strength member and jacketed, providing a small, high fiber count cable. This type of cable is idealfor outside plant trucking applications, as it can be made with the loosetubes filled with gel or water absorbent powder to prevent harm to the fibersfrom water. It can be used in conduits, strung overhead or buried directlyinto the ground. Since the fibers have only a thin buffer coating, they mustbe carefully handled and protected to prevent damage.

1.14.5 Ribbon Cable:

This cable offers the highest packing density, since all the fibers are laid outin rows, typically of 12 fibers, and laid on top of each other. This way 144fibers only has a cross section of about 1/4 inch or 6 mm! Some cabledesigns use a “slotted core” with up to 6 of these 144 fiber ribbonassemblies for 864 fibers in one cable! Since it’s outside plant cable, it’s gel-filled for water blocking.



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1.14.6 Armored Cable:

Cable installed by direct burial in areas where rodents are a problem usually

have metal armoring between two jackets to prevent rodent penetration.This means the cable is conductive, so it must be grounded properly.

Aerial Cable: Aerial cables are for outside installation on poles. They can belashed to a messenger or another cable (common in CATV) or have metalor aramid strength members to make them self supporting.

1.15 Losses of optical fiber

1.15.1 Junction Losses

The amount of light lost in a junction is affected by:• The alignment of the fibers in the splice• The sizes of the two fiber cores• The alignment or shapes of fiber cores—most are circular, some are oval



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• The properties of the fibers—scattering coefficients can vary from fiber tofiber

Proper core alignment is strongly influenced by consistent and tightly

controlled fiber geometry. When splicing two fibers together, more exactcore alignment yields a better, lower-loss splice. Core/clad concentricity is ameasure of how well the core is centered in a cable; tighter tolerances meanthat the fiber core is more precisely centered in the cladding glass.Tight concentricity tolerance is especially important when using splicingtechnologies and equipment that do not actively align the fiber cores beforesplicing, as with mechanical splices and v-groove alignment fusion splices(single or mass). For example, as many as 12 fiber splices are madesimultaneously in a mass splice, with no opportunity to individually aligneach fiber core.In single-fusion splicing techniques, tighter core/clad concentricity means

splices are done right the first time, every time. Geometrically optimized fiberprovides superior and more consistent splices, thereby reducing or eveneliminating the need for splice loss verification.

1.15.2 Backscatter and Optical Power Loss

Even coherent laser light is subject to power loss as it propagates through afiber. The glass in fiber optic cable is produced from silicon and otherelements to make it thin and flexible. Optical fiber, although much higher inquality than window glass, is not pure - it contains imperfections, impurities,and variations in its index of refraction. These flaws can cause some of the

light traveling down the fiber to be scattered in all directions, resulting in theloss of power.Scatter that is directed back toward the laser source is called “backscatter”,a property that is very useful for fiber cable measurements. Light travelingthrough a uniform section of fiber produces backscatter that decreasesuniformly over the fiber length due to attenuation of the return signal. Splicesor connectors create distinctive deviations in the-backscatter caused by attenuation of the return signals from the far side ofthe junctions. These deviations are detected as “events” whosecharacteristics can be used to identify their properties and locations.Glass is transparent to some wavelengths of light and absorbs others.

Scattering varies with the color of the light. As the wavelength gets longer(toward the red end of the spectrum) the scattering diminishes — doublingthe wavelength reduces scattering by a factor of sixteen. The 1310 nm and1550 nm wavelengths used in fiber optics communications systems wereselected for their ability• to pass through the glass in optical fiber with theleast amount of loss. The 850 nm wavelength is used because the lightsources• are relatively inexpensive.



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Figure 11 shows how impurities in a fiber attenuate the power of the lightpassing through it.

Power in fiber is measured in decibels (dB) - logarithmic units of powers of10. The equation for power gain or loss is:

Loss = 10 log10 (Output Power/Input Power)

Figure 12 shows an example of a loss of one half of the power in a 9 kmfiber link — a power loss of ˜3 dB [10 logl0 (1/2) 10 logl0 (0.5) 3.]

1.16 Ampli fiers Signal Conditioning Elements in an Optical Network

Amplifiers and multiplexers are used to improve the quality and capacity ofoptical communication networks. Amplifiers strengthen optical signals torestore power that has dissipated over long distances. Multiplexers allowmultiple signals to be carried simultaneously through a single fiber.

Amplifiers are used to strengthen the communication signal as theypass through the fiber without breaking the signal path. Most amplifiers



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employ special erbium-doped fiber elements that combine energy from anexternal light source with the signal to increase its energy. Newer Ramanamplifiers use backscattering properties within normal fibers to amplify thesignal.

1.17 Dense Wavelength Division Multiplexing

Wavelength Division Multiplexers (WDM) provide a method of sending morethan one light signal down a fiber at the same time — each at a differentwavelengths. WDM’s are passive optical component modules that usespecially treated and notched sections of fiber called “diffraction gratings”.They are bi-directional - the same device combines wavelengths in onedirection for transmission arid separates them for reception in the other (seeFigures 13 and 14). The light waves can also be shifted to otherwavelengths and added to other fibers to suit various applications.

Dense Wavelength Division Multiplexing (DWDM) enables service providersto increase bandwidth without the cost installing additional fiber. DWDMcommunication systems use multiple WDM’s to transmit multiple laser lines(channels) through fiber optic cables, allowing the fiber to carry moreinformation. Current DWDM systems are capable of combining multiplechannels into a single fiber.



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2.1 Introduction of optical fiber Communication

Optical fiber communication systems have moved rapidly from the researchlabs into commercial application. When the attenuation inherent in the

optical fiber was reduced to levels that made fiber economically attractive forlong haul communications, sources and detectors were ready and availablefor commercial applications. Current research includes new fluoride fibermaterials, with attenuation orders of magnitude smaller than is possible withsilica fibers, and optoelectronic devices for use at the still longerwavelengths that will be attractive with the new fiber materials

2.2 Definition of Transmission

Transmission is the sending or passing of something, such as a message ordisease from one place or person to anotherTransmission is the act of

passing something on.

Specifically, it may refer to:

○Transmission (mechanics), a gear system transmitting mechanical power,as in a car○ Transmission (telecommunications), the act of transmitting messages overdistances○ Transmission (medicine), the passing of a disease○ Transmission (magazine), a literary magazine based in the UK○ Transmission coefficient, in physics, chemistry, and optics.

○ Transmission (TV series), a British music television programmed shown inthe UK.○ Electric power transmission, one process in the delivery of electricity toconsumers○ Data transmission, the conveyance of information from one space toanother○ Dharma transmission, the formal confirmation of a student's awakening inZen Buddhism○ Transmission (spiritual), the act of passing on wisdom or enlightenmentfrom a spiritual master to a disciple○ Transmission (genetics), is the passing on of genetic information.



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2.3 Types Telecommunications Transmission

Telecommunications Transmission is three types

1. Micro Wave Transmission communications2. Optical Fiber Transmission communications3. Satellite Transmission communications

2.4 Definition of opt ical fiber Communication

Fiber-optic communication is a method of transmitting information from oneplace to another by sending pulses of light through an optical fiber. The lightforms an electromagnetic carrier wave that is modulated to carry information

The process of communicating using fiber-optics involves the following basic

steps: Creating the optical signal involving the use of a transmitter, relayingthe signal along the fiber, ensuring that the signal does not become toodistorted or weak, receiving the optical signal, and converting it into anelectrical signal

Optical fiber can be used as a medium for telecommunication andnetworking because it is flexible and can be bundled as cables. It isespecially advantageous for long-distance communications, because lightpropagates through the fiber with little attenuation compared to electricalcables. This allows long distances to be spanned with few repeaters.

Additionally, the per-channel light signals propagating in the fiber can be

modulated at rates as high as 111 gigabits per second,[12]

although 10 or40 Gb/s is typical in deployed systems. Each fiber can carry manyindependent channels, each using a different wavelength of light(wavelength-division multiplexing (WDM)). The net data rate (data ratewithout overhead bytes) per fiber is the per-channel data rate reduced bythe FEC overhead, multiplied by the number of channels (usually up toeighty in commercial dense WDM systems as of 2008).



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2.6 Block diagram of optical fiber communication

Information

source

Electrical

Transmit

Optical

Source

Destination

Optical Fiber Cable

Optical

Detector

Electrical

Receiver



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PLANNING OF OPTICAL FIBER TRANSMISSION



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3.1 Planning

For uninterrupted telecommunication communication system need to goodtransmission system. In modern telecommunication communication system

use Optical fiber for good transmission Path. When need to carry muchmore data to long distance must be needed optical fiber as a transmissionPath.

For plan to route an optical fiber cable line to households is in progress. Inthis planning, generally, the object households to which the optical fibercable line is connected are divided into several blocks. The trunk line is thenconstructed in a tree-like fashion in each block utilizing electric powercompany or communication firm poles. A closure (splice closure) is installedon a specific pole of the trunk line, and branch lines extend from the closureto respective households

3.2 Rout survey

The model method for conducting duct integration test (DIT) and CableBlowing is based on a Route Survey to be first carried out by the DIT/cableblowing sub-contractor’s regional manager. This route survey is conductedin conjunction with the customer’s site manager in-charge.Purpose of the route survey is to:• Meet the customer’s site manager in-charge.• Obtain from him a line diagram of the stretch with all incomplete sections(ducts not laid) with their lengths and expected dates of completion marked

on it.• Physically go over the route, including incomplete sections, and couplerpoints (to check and see if coupler points marked on the line diagram arealso marked on the route).• Observe and note the condition of the route, including bridges, railway/roadcrossings, horizontal directional drilling (HDD) points, city/built-up areas.• Obtain other information like status and availability of cable drums.It has been observed that the productivity of blowing operations is adverselyaffected due to ignorance about certain vital information before deploymentof blowing team. The most important being the status of duct laying in termsof nos., lengths and locations of disconnects and their expected date of

completion.It is, therefore, recommended that before deploying a blowing or DIT teamon a stretch, a route survey should be carried out by the Regional Manager.The route survey should include following activities:• Acquiring line diagram of the stretch with all disconnects along with theirlengths marked on it and their expected dates of completion.• Physical verification of the route, all disconnects coupler points (if couplerspoints are marked on the line diagram are marked on the route as well)



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• Noting the condition of the route• Other information like cable drum status, no. of drum availableThe above information should be transferred onto the Route Survey formatfor every 10 km length

A summary of this information along with certain basic information likenames, designations & addresses, phone! fax no. of main contact personand site engineers, numbers of ducts laid, duct IDOD, REG point locations,cable drum and cable specification related information, and any specialrequirement depending on the site conditions, etc. should be put into in theform of Route Survey Summary Report format and handed over to the DITteam before its mobilization to the site.

3.3 Work f low chart:

Block diagram for work flow chart:

Route Survey

Line diagram + Coupler to

Coupler duct length

DIT

Rectification

DIT Reports

Cable Blowing

Blowing Report



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3.4 Route survey summary report f rom

Date of Survey: / /200 Route from: To:Main Contact person at site:

Name, designation & Address:

Phone:Fax :

Customer/Contractor Site

EngineerName:a)b)c)d)e)

Survey Findings / Observations:Total Km surveyed: Km Nos. of duet s laid: 2/3 /4/ Duct ID/OD:Duct Color(s) Primary Duct color:

Total Km duct laid: 1cm Total Km duct not laid

Total Km laying in progress: Km Total Km ready for DIT: KmTotal Km blown: Km Total Km ready for blowing: KmRoad Under: NH- Km, SH: Km, DR: Km, R&H: KmRoad condition: Good I BadDecoiler: Used / Not Used Coupler marked: all most all / few / noneLine diagram with coupler points and distance: Available / Not Available

REG points: (a) (b) (c) (d)Disconnect Information : Total Nos. of disconnect(s) in the route: Nos.S.No MS Disconnect

Length (Km)Expected Dateof completion

Reason fordisconnectFrom To

1 / /2002 / /200

3 / /2004 / /2005 / /2006 / /2007 / /200Cable Drum Information:Nos. of drum available: Nos. of drum OTDR test carried out:Drum size: 3km/4km/Skm/ Cable Make :Cable diameter (mm): Type of cable:Wt. Of Cable: gm/m Type of reinforcement: 2GJ I FRP /Distance between site & store: Km Drum planning: carried out / not carried out

Special Requirements:Hose length: M Compressor:Petrol Pump Available / Not Available Food : Available / Not Available

Drinking water: Available / Not Available

Staying: Available / Not Available

Additional Information for BIT I blowing team:



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DUCT HANDLING STORAGE AND DUCT LAYING



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HDPE duct protects the cable from destructive elements in the ground suchas: acids, chemicals, salts, alkalis and hydrocarbons. Duct will not becomeoval, flatten out or elongate during its installation.• Ease of Installation

HDPE ducts are flexible but durable. It is possible to follow the route aroundbends without any need for special elbows or heat treatment. HDPE ductscan be pulled into concrete, PVC or steel main ducts. It is possible to installducts mechanically or manually. Ducts can be laid in temperatures belowfreezing point (as low as -20 degrees C) when fiber optic cable cannot beinstalled. This helps expedite the installation of the telecom network.• Future Access to the DuctExcavation cost is one of the more expensive elements of the building of thetelecom network. Also it is becoming more and more difficult and expensiveto get permission to dig specially in urban areas. Ducts enable theupgrading of telecom network without digging all over again. The old cable

can be removed and the new one installed with access from manholes. Additionally, cables. can easily be installed in spare ducts provided at timeof original installation.• Replacement of CableThe permanently pre-lubricated HDPE duct permits easy removal andreplacement of the fiber optic cable without any damage to the fibers ofeither of the two cables or the duct.

4.3 Duct transportation

During transportation and storing at the site, it is necessary to seal the ends

of the duct with the proper End caps against water penetration or otherimpurities. Sand, soil or water and other impurities significantly increase thefriction between the duct and the cable outer sheet.Ensure that the Duct coil is strapped properly at four places.While transporting the duct from factory, it is should be ensured that thetrucks are properly sealed. In ease of any discrepancy/damage to duct,please report immediately with details of Truck No., damaged Coil No.,extent of damage (if possible photographs), so that the matter can be takenup with the transporters.Similarly, it is advisable not to put any heavy objects like tools, G.I./RCCPipes etc., while transporting ducts from main store to actual laying location

at site.



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4.4 Method of Loading & unloading for high density polyethylene ducts

Using wooden or metallic plankUsing Rope or Belt

Using Chain-Pulley blockUsing Raised GroundUsing Boom truckUsing Crane

4.4.1 Using wooden or metallic plank

Open the tail board of the truck carrying the duct coil and put wooden ormetallic planks at appropriate places, (refer following figures) sloping fromthe floor of the truck to ground. Roll down over these planks to rest on theground.

Duet Coil can also be dropped from the floor of truck on sand or soft soil bedof about 12” height or more.Never ever drop the Duct Coil from the floor of the truck on hard ground/road



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4.4.2 Using rope or belt

Open the tail board of the truck carrying the duct coil and hang the coil byrope or belt. if we want to unload the duct coil rope or belt loose slowly until

the coil touch ground.

4.4.3 Using raised ground

When the duct storage location is higher then road position it is possible.The truck plate form height is equal of the existing duct storage height. Thisprocedure is easy to handle load and unload the storage ducts.



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4.4.4 Using boom truck .

This procedure is fully mechanical .this types of system for loading andunloading use a crane which is attested on the truck.

4.4.5 Using crane

This is a system for loading and unloading by using an individual crane.



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4.5 Duct storage

Avoid exposure of HDPE Ducts to direct sunlight, which may adverselyaffect the physical and mechanical characteristics of duct.

Keep DPE Duct covered during storage for a long period.Keep the ends of HDPE Duct capped or plugged to avoid entry of dust, dirt,water, etc.Keep HDPE Duet away from Chemicals, inflammable material, etc.Do not keep any heavy material on HDPE Duct during transportation andstorage.



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4.6 Trenching

A long narrow ditch in the ground, such as one for laying a pipe in ditch.

4.6.1 Right of way permission

On behalf of the client, Aster Infratek obtains necessary statutorypermissions from regulatory bodies. Single Line Diagram (SLD) is made todetermine the jurisdictions and permissions obtained.

State Highways Railway Department Roads & Buildings Department Municipal corporations Panchayath Boards Irrigation department National Highway Authorities Forest Department



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4.6.2 Specifications for excavation of trenches

º Standard depth will be measured from lower side of natural ground level tothe base of the trench.

º Standard depth for normal soil and soft rock: At least 1500 mm (1.5 M).

º Standard depth for hard rock: At least 900 mm (0.9 M) provided the rockstars from earth crust.

º Width of trench: 400mm at top and 300mm at the bottom.

º Different clients have slightly marginal differences in trench depth and wecater to the needs of the customers.

º Outside the city limits trench will normally follow outer boundary of theberm.

º Where the berm has burrowed pits or forestation, or when cable is to belaid along culverts/bridges or cross-streams, trench may be made closer toroad edge, or in some cases, over embankment or shoulder of the road.

º Line up of trench would be such that HDPE duct(s) will be laid in straightline, both laterally as well as vertically except at locations where it has tonecessarily take a bend because of change in alignment or gradient oftrench.

º Minimum radius of two meters will be maintained, where bends arenecessitated.

4.6.3 Observations on trenching

1. Check for modulations & undulations of the trenchGet the bottom of the trench rectified before duct laying2. Check for stones & debris at the trench baseGet the stones & debris cleared3. Mechanized trenching leaves trench bottom with sharp

Projections causing duct deformationLevel the trench base before duct Laying.4. Sudden depth changes because of Culvert I Bridge crossingsNeed to maintain the minimum bending radius of trench or trench slope atmax. 3Q0 gradient5. Sharp bends at HDD points damages ductsNeed proper bending radius to be maintained for entry into GI pipe at HDDpoint



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6. Watch out for 90˚ Vertical trenchCompact the soil under & behind the bend.

4.6.4 Back filling

º Trench will be initially filled with sieved soil or sand in Rocky Terrain forabout 10 cm which will act as a cushion / padding and then duct is placedgently over it.

º After that another layer of 10 cm of fine sieved soil or sand is poured andthen entire trench is backfilled with excavated material.

º Under normal soil conditions duct is directly laid in trench and backfilled. Adequate dry compaction will be done before crowning.

4.6.5 Crowning

º When backfilling has been done up to ground level a hump of soil is madeto cater for soil settlement.

º Entire excavated soil will be used for back filling.

º Crowning will be confined to width of trench only.

4.7 Duct Mounting Steel Reels

4.7.1 Using Vertical de-coiler

○ Used for laying of duct coils without formation of twists andentanglements.○ Helps in laying duct straight in the trench thus reducing the coil set.Place flange I on ground Place the duct coil on flange



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4.7.2 Coil mounting horizontal de-coiler

○ Place the coil horizontally on top of the circular metal frame & insert thevertical bars at the coil.

4.8 Duct laying

o Ducts will be laid in a flat bottom trench, free from stones, and sharpedged debris.o The duct would be placed in trench as straight as possible. However, atbends horizontal and vertical minimum bending radius for duct of 1300 mmwould be maintained.o Ducts will be laid preferably using specially designed dispensers.o Ducts shall be free from twist and collapsed portions. Any such portionwill be rectified before backfilling by using couplers.o Ends of ducts will always be closed with END PLUGS to avoid ingress ofmud, water or dust.o Prior to aligning the ducts for jointing, each length of the HDPE duct will

be thoroughly cleaned to remove all sand, dust or any other debris that mayclog, disturb or damage the optical fiber cable when it is pulled or blown at alater stage.o The ducts will be joined with couplers using duct cutter & other tools andwill be tightened and secured properly.o The duct joint will be practically airtight to ensure smooth cable blowingusing cable blowing machines.



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o Gl and / or RCC pipes will be used as additional protection for the HDPEducts at rail / road crossings, built-up area/city limits, on culverts andbridges, as required.o Chambering or concreting around RCC/ Gl pipes as additional protection

on bridges, culverts and also on stretches wherever depth of excavation isless than specified will be done.o Reinstatement of excavated trench will be done with proper compaction.

4.8.1 Procedure for duct installation

Determine the direction of installation and set the reel. (Duct should alwayscome from the bottom)

Unroll the duct to the required length, spacing workers as shown below.

One supervisor should put his handaround the duct and walk throughthe entire length to inspect it for

physical damage and repair the ductas required. Place the duct into thetrench.

Let two workers stand on the duct at point A. At point B let two workers puttension on duct by pulling it and at point C put some backfill and compact.



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Backfill the trench at approximate 2-Mtr. intervals or continuously as shownin Figure below, keeping the duct under continuous tension, just to install itstraight.

4.8.2 The basics of ducts laying

4.9 Duct Integrity testing

4.9.1 Duct Integrity testing procedure

Purpose of Duct Integrity Test is to ascertain and ensure the suitability of theduct for cable installation through jetting. It is first necessary to ensure that

the duct into which cable is to be installed is continuous over the length ofthe duet. Some reasons for lack of continuity are:

• Missing sections of duct• Couplers not connected• Overlapping of ducts



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The Air Test establishes duct continuity. Air is introduced from one end ofthe duct. If air comes out from the other end of the duct then it is establishedthat the duct is continuous. If no air emerges then the fault is to—beidentified and corrected before proceeding further. Duct overlap can lead to

potentially very dangerous situations and should be corrected promptly.Second step in the DIT Test is to establish that there is a clear passage forthe cable to go through the duct. Possible reasons for lack of clearpassageway are:• Kink in the duct• Blockage in the duct

These deficiencies are to be corrected before proceeding further. Kink in theduct may be caused at the duct laying stage when backfilling may havebeen done without taking care to keep boulders out of the way and out ofthe trench. A fallen boulder on top of a laid duct can cause the problem. The

kink may also have been caused at the de coiling stage if this is attemptedwithout use of a decoiler.The kink in the buried duct is located through the Shuttle Test. A suitableshuttle is first passed through the duct. The shuttle will get stuck at the pointwhere the duct is either kinked or blocked. Next a transmitter is passedthrough the duct. It gets stuck behind the shuttle. The path of the duct isthen tracked with a receiver. As the receiver passes over the transmitter thesignal from the transmitter is heard loud and clear. In this way thetransmitter, and just ahead the shuttle, and just ahead the kink are located.The spot is marked and the trench has to be dug up again. The boulderresponsible for the kink is removed. The portion of the damaged duct is cut

out and replaced with good duct of equal length. Joint with laid duct is madewith push fit coupler.Cable installation through jetting can be carried out successfully only undera pressure of 10 bar. Before cable installation is attempted it is necessary toverify that the duct can bold this pressure. This is the major purpose of thePressure Test.Possible reasons for failure of DIT pressure test are:• Leakage at couplers• Puncture in ductCoupler leakage is caused by improper installation of coupler. A puncture inthe duct can result from improper handling of the duct. A sharp-edged

boulder if it should come to rest on top of the buried duct can also puncturethe duct. Air leakage from the leaking coupler or the punctured duct is thetell tale sign of the problem which can then be rectified.Thus in summary the DIT test is conducted prior to cable installation with aview to check and if necessary rectify the duct so it is made suitable forcable installation. The possible duct faults that may show up during the DITtest process are:



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Points Distance from PTB (M)Minimum Maximum

lor3kmPoint 800 1400Oor4kmPoint 1800 2400

Following example illustrates how in a practical situation coupler points willbe earmarked as 0,1,2,3,4 km point for digging of pits. The 4 km patchbetween MS 100 to MS 104 has been taken for DIT.

• MS 100 is taken as 0 km point (DIT starting point).• MS 102 is taken as 2 km point, its distance from 0 km point is 1 900M.• Coupler point at a distance of 800M from MS 100 is taken as 1 km point.• Coupler point at a distance of 900M from MS 102 is taken as 3 km point.• Coupler point at a distance of 200M from MS 104 is taken as 4 km point.• The total patch length on which DIT would be performed is 4100M.

• Before starting DIT dig all 0,1,2,3,4 km points for 12 km and engage 2labors for advance pit digging for opening further points.• Visually check for any overlaps, if found, rectify them.

The figure shows:• A 4km path.• Pets & compressor should be fixed at 2 km point.• Couplers at all the points, i.e., 0,1,2,3,4 km points should be opened inadvance.



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• All the testing i.e., Air, Shuttle, Sponge and Pressure test should beperformed in 2-0 section (Up stream) first and then in 2-4 section (Downstream).• It is assumed that DIT for two duets is to be performed: the primary duet (in

which immediately after DIT blowing to be done) and secondary or spareduct (which is left for future use). At a time DIT for 2 km duet length for boththe ducts would be performed (i.e., if in one duet air & shuttle has passed,but the other duet has failed in shuttle test, then do not carry out sponge andpressure test for the first duet. Only after clearing air/shuttle in both primaryand secondary duets, pass sponge and carry out pressure test for bath thechief’s simultaneously• To start with, 3 technicians are placed at 0 km. 1 km and 2 km point.During pressure build up (pressure test) in 2-0 section (Upstream), 1 kmperson moves to 4 km point and 0 km person moves to 3 km point, whereas,in case of a fault, once the transmitter has been blown, 0 km person moves

to 4 km point and 1 km person pin points the transmitter signal, marks thearea for digging with lime powder and engages 2 labor for digging and thenmoves to 3 km point.If fault occurs on both the sides, i.e., 2-0 section (Up stream) and 2-4 section(Down stream) then assess the pit opening condition at 2-0 section, if the pitopening is likely to take more than 15 mm. then move to next 4 km patchand start performing DIE If fault occurs on both the sides of the next 4 kmpatch then come back to previous 4 km patch, if by this time the pit is readyand problem has been rectified. Otherwise move to still next 4 km patch.

SCHEMATIC DIAGRAM, NOMENCLATURE AND BASIC DIT



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NOTE: The sequence of shuttle and sponge can be interchanged dependingupon the condition of the duct. If water/mud is coming out at 0 or 4 kmpoint then sponge cleaning can be carried out before shuttle test. Normally,shuttle test should be carried out before sponge cleaning because if sponge

is stuck then de-blowing has to be done. Never blow sponge first whenback-pressure is observed (back pressure indicates there is blockage andsponge may get stuck.

4.10 Types of duct Integrity test.

Types of Integrity test

1. Air blowing test2. Shuttle blowing test

3. Transmitter blowing test4. Sponge blowing test5. Pressure Test

4.10.1 Air blowing test

Normally, the person at 2 1cm point would encounter any one of thefollowing threeSituations:

1. Normal: Allow full discharge with a 5 bar, 100 cm compressor and 1400-1500 rpm.2. Low pressure: If the observed pressure at 0 or 4 km point is less than thenormalPressure then there may be possibility of air leakage from a loose coupler inbetween.3. Back Pressure: If the observed pressure is more than the normalpressure then theremay be possibility of a blockage giving rise to back pressure.In case of low or back-pressure the action to be taken would also dependupon the response from person at 0 km or 4 km point. The response of 0 km

or 4 km point person may be. any one of the following:Normal air flow: Action: Blow shuttle.Low air pressure:Problem: 1. Loose Coupler(s)2. Duct Puncture3. Partial Blockage

Action: Check coupler at I km point for any leakage.



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If no leakage found at 1 km point, blow shuttle.Back pressure observed at 2 km pointProblem: Blockage

Action: Open coupler at 1 or 3 km point and check whether back pressure is

observed. If no backpressure is observed, then blockage is in section 1-0 or3-4 section. Blow shuttle,No Air FlowProblem:1. Duct overlap2. Duct missing3. Dead blockage

Action: Open coupler at 1 or 3 km point and check whether air is coming ornot. Jf air is coming then there is duct overlap or duct missing in 1-0 or 3-4section.Couple I or 3 km point and send air, visually inspect 1-0 or 3-4 section for

overlap and air leakage.If overlap or air leakage is not found blow transmitter and pinpoint with thereceiver.Water / mud coming out at 0 or 4 km pointProblem: Presence of Water I mud in the duct:

Action: Continue blowing air for 5-10 mi until water / mud stops coming.Blow sponge.If water continues to come after 5-10 mm. it means there is loose coupler inwaterlogged area. Continue blowing air and check visually the trench forwaterlogged area for air bubbles coming out.

4.10.2 Shuttle blowing test

Normally, shuttle would come out at a distance of 2 km within 3 mm. and ata distance of 1 km within 1 mm. (All the shuttles should be numbered andwhile blowing shuttle, shuttle number should be noted.)Shuttle Stuck• If the shuttle does not come out within 3 mm. continue blowing air foranother 2-3 mm. Jf still the shuttle does not come out, then:• Switch on the receiver and place the receiver on the duct at 1 or 3 kmpoint. Blow the transmitter and continue air for 3-5 mm. for the transmitter totravel to the fault location, while the transmitter moves from 1 or 3 km point

the receiver makes sound as well as the transmitter make sound due to theimpact on the duct.• If at 1 or 3 km point the receiver makes sound then the shuttle andtransmitter is stuck in 1-0 or 3-4 section and if at 1 or 3 kin point the receiverdoes not make sound then the shuttle and transmitter is stuck in 2-1 or 2-3section. Accordingly, move with the receiver in 1-0 or 3-4 or 2-I or 2-3section to pinpoint the transmitter.



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• Mark the pinpoint and 2 to 2.5 meters. on its either sides with lime powderfor pit digging.• Many a time the shuttle gets stuck due to minor kink and while transmitteris blown the shuttle and transmitter conies out. Make sure while transmitter

is Mown the catcher is fixed at 0 or 4 km point else the transmitter may getdamaged.

4.10.3 Transmitter blowing test

Transmitter is to be blown in following two conditions:1. Shuttle is stuck,2. When air is not coming at 0 or 4 km point, then open coupler at I or 3 kmpoint and check whether air is coming or not. If air is coming then there isduct overlap or duct missing in 1-0 or 3-4 section. Couple 1 or 3 km pointand send air, visually inspect 1-0 or 3-4 section for overlap and air leakage,

If overlap or air leakage is not found then only blow transmitter and pinpointwith the receiver. Before howling transmitter ensures that there is no overlapor else the transmitter would fly away.

All the transmitters should be numbered and while blowing transmitter,transmitter number should be noted.

Always blow transmitter at 2 bar pressure or else transmitter would bedamaged. Before blowing transmitter reduce the pressure valve regulator tozero from Pressure Testing Equipment (PTE) and then slowly increase thepressure valve regulator to 2 bar.Never blow transmitter in the same section in both the duct (e.g., for bothprimary and secondary ducts) because it will be very difficult to identify &

which duct is the faulty one. Both the transmitters may get stuck at the sameplace requiring the person to walk 1 full km to locate for any othertransmitter signal.Pinpointing: After the transmitter is blown, move with the receiver over thetrench. When signal is received, slow down, keep the blade of the receiververtical and move slowly backwards and forwards over the suspected area,reduce the sensitivity for a narrower response and pinpoint. Mark thepinpoint and 2 to 2.5 mtrs. on its either sides with lime powder to beexcavated. Engage two labors and note the time when the excavation workstarted.



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4.10.4 Sponge blowing test

Normally, sponge would come out at a distance of 2 km within 3 mm. and ata distance of1 km within I mm.Sponge Stuck• If the sponge does not come out within 3 thin, continue blowing air for

another 2-3 mm. If still the sponge does not come out.• Switch on the receiver and place the receiver on the duet at I or 3 km point.Blow the transmitter and a small piece of sponge after the transmitter andcontinue air for 3-5 rain, for the transmitter to travel to the fault location,while the transmitter moves from 1 or 3 km point the receiver makes soundas well as the transmitter make sound due to the impact on the duct.• If at 1 or 3 km point the receiver makes sound then the shuttle andtransmitter is stuck in 1-0 or 3-4 section and if at 1 or 3 km point the receiverdoes not make sound thenthe shuttle and transmitter is stuck in 2-1 or 2-3 section. Accordingly, movewith the receiver in 1-0 or 3-4 or 2-1 or 2-3 section to pinpoint the

transmitter. Keep the duct pressurized and move with the receiver in 2-1 or2-3 section to pinpoint the transmitter.Mark the pinpoint and 2 to 2.5 meters. on its either sides with lime powderfor pit digging.



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4.10.5 Pressure Test

While building up pressure increase the pressure to 5.5 bar and close theinlet valve. Wait for sometime to stabilize the pressure, if the pressure does

not drop, release the pressure to bring it to 5 bar, if the pressure drops,increase the pressure by opening the inlet valve to build up pressure of 5bar.Pressure test to conducted for both the ducts simultaneously for a 2 km ductlength. Pressure test to be conducted at 5-bar pressure for 30 mm. If thepressure does not drop below 4.5 bar within 30 mm. the pressure test ispassed.Pressure Test FailedIf the pressure drops below 4.5 bar within 30 mm. then the pressure test hasfailed. Thisindicates coupler leakage or a puncture in the duct.

In case the pressure test has failed the following action to be taken:• Check coupler point at 1, 2 or 4, 2 point as well as the end coupler at 0 or 4km point. If there is no leakage in these points, conduct pressure test for 2-1or 2-3 section in order to know the pressure drop section.• If there is pressure drop in 2-I or 2-3 section, it indicates that there isleakage in this section. Dig all marked coupler point in this section andcheck for leakage.• If there is no pressure drop in this section then it indicates that there isleakage in 1-0 or 3-4 section. Dig all marked coupler point in this section andcheck for leakage• After rectifying the coupler points conduct pressure test in order to ensure

the pressure test has passed. In ease the pressure test has failed makesure there is no marked coupler point.



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CABLE PULLING AND JETTING



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5.1 Defini tion Cable pul ling :

Traditionally fiber optic cables were pulled through cable ducts in the sameway as other cables, via a winch line. Every time a bend or undulation in the

duct is passed the pulling force is multiplied by a friction dependent factorwhich can be reduced by using lubricant. This means that the higher thelocal pulling force is, the higher the friction will be which the cable isexperiencing while being pulled against the internal duct wall. This "capstaneffect leads to an exponential force build-up with pull distance, producinggenerally high pulling forces.

5.2 Defini tion Cable jetting:

Cable jetting is the process of blowing a cable through a duct whilesimultaneously pushing the cable into the duct. Compressed air is injected

at the duct inlet and flows through the duct and along the cable at highspeed. (Preferably, no suction pig is used at the cable head.) The highspeed air propels the cable due to drag forces and pressure drop. Thefriction of the cable against the duct is compensated locally by thedistributed airflow and large forces that would generate high friction areavoided. Because of the expanding airflow, the air propelling forces arerelatively small at the cable inlet and large at the air exhaust end of the duct.To compensate for this, an additional pushing force is applied to the cableby the jetting equipment. The pushing force, acting mainly near the cableinlet, adds synergistically with the airflow propelling forces, increasing themaximum jetting distance considerably. Special lubricants have been

developed for cable jetting to further offset friction.

5.3 Advantages of jetting compared to pulling

1. Longer installation distances can be reached2. Installation distance less dependent on bends and undulations in duct3. Forces exerted on the cable are lower4. Easier use jet in tandem operation5. The step of installing a winch rope is avoided6. Equipment is needed only at one end of the duct route



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5.4 Block diagram of cable jetting system.

5.5 Determine the cable size due to duct size

The inside diameter of the duct should ideally be two times the outsidediameter of the cable. The appropriate duct size for different sizes of cablesis given below:

Recommended Duct Size (OD/ID), OutsideDiameter (OD) of Cable, mm

32/369.0-12.5

40/33

13.0-16.050/42 16.5-20.0



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5.6 Compressor

The compressor should have the following characteristics to ensure effectivecable jetting:

Discharge Pressure 10 bar Air Delivery 450CFM After Cooler Built-in

6.7 Types of Cable jetting machine

1. Cable jet Machine (with pneumatic drive) is the suitable machine forinstallation of cable up to 15 mm in diameter.

2. Super jet Machine (with hydraulic drive) is the right choice for cables withdiameter in the range from 14 to 32 mm.

5.7.1 Cable jet machine:

Cable jet – the “no-pull” blowing-in system for fiber optic cables Ø 6-18mm. This category of sensitive cables demands the delicate “feel” of theCable jet. The cable is moved gently by air through the conduit. Suitable forPEHD conduits up to Ø 63 mm. A compressor with an operating pressure of12 bar and a delivery of at least 10 m3/min. is required for successful airinjection in any position of a tube up to internal Ø of 40 mm.

A detailed specification is available on request.



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5.7.2 Super jet machine

Super jet – the “no-pull” cable blowing – in system featuring high hydraulicpower for large and heavy cables Ø (8) 14-36 mm.

Super jet operates on the basis of the same principle as the Cable jet.Suitable for PEHD conduits up to Ø 63 mm. A compressor with an operatingpressure of 12 bar and a delivery of at least 10 m3/min. is required forsuccessful air injection in any position into conduits with internal Ø 40 mm.

5.8 Advantages of cable jet machine compared with super jet

The cable jet can blow in 12 Km of cable in 1 day and is the safest methodavailable. With zero pull on the fiber optic cable, overloading of the cable isnot an issue. This eliminates the need for expensive bulky strengthmembers in the cable. Reducing the unit cost and weight of the cable. Thesuitable COMPRESSOR required for the system must have the followingcharacteristics: 12 bar maximum pressure (minimum 8 bars) and 10 m3/min.flow rate for placing cables in ducts having an internal diameter not

exceeding 42 mm and 15 m3/min. for ducts not exceeding 50 mm innerdiameter. To secure performance when the ambient temperature exceeds30 °C, the use of an after cooler is recommended. A special unit may besupplied, should the compressor not be equipped with an after cooler



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5.9 The performance of the cable jet system is defined as follows

-INSTALLED LENGHTS using one machine: 1000 - 3000 m and more,depending on quality and characteristics of duct and cable and ambient

temperature.- The LAYING SPEED varies between 40 and 100 m/min. and over,depending on conditions.-Required MANPOWER: for the first Cable jet 3 operators, for eachadditional machine (cascade) 1 operator.Cable jet is not just a method, but a range of world-wide patentedequipments.With a weight not exceeding 20 kg, in operational mode, the Cable jet is avery compact cable laying machine. Its air powered pushing mechanismconsists of 8 notched drive-wheels. The Cable jet is supplied with cable-sealing inserts for diameters ranging from 9 - 18 mm, together with duct

inserts for most common dimensions, 32, 40 and 50 mm (other sizesavailable on request). It is supplied with 2 metallic boxes, one for theapparatus, the other for the accessories, spare parts, inserts and distancecounter.

5.10 Jetting Efficiency

Cable drums are generally equipped with 4 km of cable, and this establishesa distance of 4 km between splicing pits. Typically drums are placed 4 kmapart on long-haul routes, midway between splicing pits. The most efficientcable installation would be 2-km jetting shots towards splicing pits in either

direction from the midway point. After jetting 2 km in one direction, a figureof eight would be created at the midway point to get to the end point of thecable in the drum. This end would then be jetted in the other direction.If the cable movement should slow down, then instead of taking the 2-kmshot the jetting shot could be limited to 1 km and cable jetting wouldcontinue so that a 1-km figure of eight could be made at the 1-km mark. Thecompressor would then be moved there to jet the remaining 1 km of cable tothe splicing pit. In the meantime the 2-km figure of eight would have beenmade at the drum point, and the compressor would be brought back here toattempt the 2-km shot in the other direction. Once again if the jetting speedshould slow down the shot could be limited to 1 km with a 1 km figure of

eight. The compressor would again be moved to jet the 1 km figure of eight.It is clear that jetting efficiency is highest when 2-km shots are successful.The 4-km cable drum is installed with one placement of the compressor anda total of 4 km of cable jetting and 2 km of figure of eight. In contrast 1-km

jet shots require four placements of the compressor and a total of 6 km ofcable jetting and 4 km of figure of eight.



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6.11 Prerequisites for Cable blowing

● Prior to moving the blowing team route survey report, summary of routesurvey report, DIT report and line and patch diagram should be available

with the blowing team. After reaching the blowing site, the blowing teammust collect the following information before commencing blowingoperations:

● Line Diagram with coupler markings (if possible coupler to coupler ductlengths) and physically verify the coupler markings on the road, tree, etc.● Blowing plan indicating:Target date for completion of blowingLoops to be left at State & National highway road crossingsLoops to be left at various bridges and culvertLoops to be left at Splicing pits

Plans for handling disconnects● Availability of cable drums as well as cable lengths at stores, OTDRtesting carried out or not and cable transport modalities.

6.12 Pre-blowing Activ ities

Following activities are to he clone before blowing is commenced:● Digging of pits at all 1km points. (These are already available if cableblowing is taken up immediately after DIT is completed — within sevendays).● Determining splicing pit locations and digging thereof in advance by

matching coupler to coupler duct lengths and sizes of the available cabledrums.● Planning for placement of cable drums of respective sizes at every 4km.(or as per the cable drum size).

6.13 Distribution of Jobs

● In order to bring in synergetic effect and maximize the productivity ofblowing operation it is recommended that the major job responsibilities maybe distributed among the four key personnel as given below:º The Cable jet Operator to take charge of overall site management

including liaison with the customer! contractor, cable drum planning, cabledrum placement, splicing pit determination, loop lengths, shot lengths andcorresponding cable readings, arrangement of consumables and spares,maintenance of equipment, checklists and reporting.● One trained operator! labor to be in charge of the blowing activity includingsetting of blowing machine into the pit, and running blowing machine.• One trained operator! labor to look after of the cable drum mounting on the

jack and its subsequent rotation and adjustment (which is essential as the



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drum slides or becomes unbalanced from time to time while the drum, isrotating), fixing bullets on the cable, setting up of compressor and itssubsequent operation, Honda set operation, cleaning and handling of thecable before being fed into the blowing machine

● One trained operator! labor to look after activities at the far end includingputting duet cleaner at 1 km point, making of loop at the Splicing Pit (SP),back filling of the SP, cordoning off the blowing area, compressor etc. forensuring the safety.Though other labor required for the blowing operation is generally hired fromthe adjacent locality and they are quite unfamiliar with the activities involved,efforts should be made to specialize them within first two or three days byusing them repeatedly for the same job as far as possible. Followingdistribution of job (during the initial days) should be made among these laborfor this purpose:● 2 labor for loading, unloading and setting up of blowing machine, Honda

set, accessories box, cable cleaning while feeding it to the machine.● 2 labor for cable drum mounting on the jack, loading and unloading of

jacks, ramps, drum rotation and adjustment, making figure of 8 from drumfor down stream blowing, feeding cable from figure 8● 1 labor for making figure of eight from the cable coming out at the far end,making loops from cable for splicing pit, backfilling go splicing pitHowever, the above specialization is not meant for limiting the use of trainedoperators or labor for any specific activity. All the persons may be used forall activities if the situation so warrants.Recommendations for Better BlowingBefore commencing the blowing, survey the route to determine the best

locations for access points for jetting machine and compressor. The RouteSurvey Reports and the Route Survey Summary Report can also be helpfulfor this purpose.The Duct Integrity Test is a must before taking up the blowing activity. TheDIT Report and the Line and Patch Diagram should also be available to theblowing team.

As a mile always blow downhill wherever possible. Make sure that theaverage route will permit the cable to be installed on a descending and notan ascending gradient.When cable blowing is carried out at high temperatures, protect the cablefrom direct sunlight wherever possible. High temperatures drastically reduce

the blow able length. Water may be sprayed over the cable drum to wet thecable and keep it cool.Duct cleaner (500 ml) and sponge should be used for duct cleaning both atpoint of cable blowing as well as at 1-km point (500 ml) for successful 2-kmjetting shots.The Super jet Machine should be in good working order. The radial pressureof the chain on the cable should be adjusted by adjusting the position of thepressure cylinder to one of three positions based on cable diameter: High for



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cable diameter less than 14mm, Medium for diameter between 14 and 25mm, and Low for diameter exceeding 25 mm. The chain tension should alsobe checked and adjusted.The time gap between DIT and blowing should be minimal. Blowing should

commence within a maximum of seven days after DIT. As far as possible the cable should not touch the ground. Figure of eightshould be laidon a tarpaulin Care should be-taken-to-ensure-that-the cable as it is fed intothe machine does not touch the ground.

A wet cloth should be used for cleaning the cable followed by a dry cloth fordrying the cable as it is fed into the machine.

6.14 Salient points during cable blowing

1. Availability of Line Diagram with all Coupler Points/HDD Points, Road/Rail

2. Crossings, GI/RCC/PCC crossings clearly marked.3. Site supervisor involved in Duct laying to be available on site.4. Spare Couplers, End Plugs available at site for rectification jobs in case ofany more rectification/temporary blowing pit5. Availability of ROW/Local/Municipal body permissions.6. Drum planning chart specifying the allocation of drums to variousstretches.7. Spare loop plan for obstacle crossing/splice pits48. Pré-positioning of Splice Chambers, based on Drum planning.9. Availability of minimum 3 No. of Cable Drums, duly OTDR tested on adaily basis at the stores.

10. Regular daily site meeting with the blowing team.



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OPERATION AND MAINTENANCE



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6.1 List of used tools

This section is a brief summary of some basic test tools that are used toinstall and maintain fiber optic cable systems.

6.1.1 Fiber scopes

Fiber scopes are microscopes designed to let you visually inspect the endsof fibers or connectors.

6.1.2 Visual fault finders

Simply shining visible light from the end of a fiber onto a surface such as awall or the palm of your hand can ensure that there are no breaks in thefiber. A visual fault finder (or locator) transmits a visible laser light wavethrough the fiber to permit an observer to see a break by the light leakingthrough the shield. Visual fault finders (VFF) use Class II lasers and shouldnever be used for any other purpose. VFF’s have a range of only about 1

km, so their use is limited to short links of fiber that can be seen; typically tothe troubleshooting of panels and jumper cables.WARNING: Never look directly into any operating laser or lit fiber Laser lightcan cause eye damage or blindness.



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6.1.3 Fiber identifiers

Fiber identifiers are simple clip-on devices that recognize signals on a fiber.They identify the presence of:

● Data traffic● CW tone● Optical tone (2 .1 GHz signal)● Dark fiber (no signal at all)

6.1.4 Optical power meters

Power meters are used to measure the loss or attenuation of the entire fibersystem including all bends, splices, and connectors between two points.Power is measured at each end of the link and compared. Excessive powerloss can indicate fiber-link problems such as bad splices, broken fiber andpoor connections, but the measurement can not reveal where the problemsare located.

6.1.5 Optical sources

Optical sources are stabile light sources that are used to perform systemloss measurements in conjunction with a power meter, qualify theperformance of a new system and troubleshoot existing systems. The power

output level of an optical source is much more stable than that of atransmitter. Optical sources are available in all common wavelengths andtransmitter types in order to match the type of system being tested.



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6.1.6 Loss test sets

Loss test sets combine an optical power meter and light source into a singlekit. A kit is

used at both ends of a fiber to perform 2-way power loss measurements.

6.1.7 Optical return loss (ORL) meters

Optical return loss (ORL) meters measure the total reflected power from afiber system. The ORL tests the fiber from one end without needing a sourceor technician at the other end. Excessive return loss can indicate systemfaults but not where they have occurred.

6.1.8 Automated fault finders

Automated fault finders are dedicated testers for detecting the locations ofmajor fiber losses. They use reflected light techniques to measure thedistance to the first major fault or the total length of a fiber. They are simplehandheld devices that are configured for a single wavelength and displaytest results in symbolic or alpha-numeric readouts. Their overall range isabout 60km. Some fault finders detect only Fresnel reflections rather thanbackscatter. They are able to measure cable lengths, but have difficulty

sensing and locating non-reflective faults.



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6.2 Junction in optical fiber cable

The junctions formed by either splices or connectors have a significant effect

on the performance of a fiber optic cable. Three basic techniques are usedto join fibers: fusion splices, mechanical splices, and connectors.

6.2.1 Definition splicing or Joint

Fiber-optic cables might have to be spliced together for a number ofreasons—for example, to realize a link of a particular length. Another reasonmight involve backhoe fade, in which case a fiber-optic cable might havebeen ripped apart due to trenching work. The network installer might have inhis inventory several fiber-optic cables, but none long enough to satisfy therequired link length. Situations such as this often arise because cable

manufacturers offer cables in limited lengths—usually 1 to 6 km. A link of 10km can be installed by splicing several fiber-optic cables together. Theinstaller can then satisfy the distance requirement and avoid buying a newfiber-optic cable. Splices might be required at building entrances, wiringclosets, couplers, and literally any intermediate point between a transmitterand receiver.

6.2.2 Types of splic ing

Mainly two type’s method splicing

1. Mechanical splicing method2. Fusion splicing method3. Connector method

6.2.2.1 Mechanical splices

Mechanical splices employ physical couplers to hold two fiber ends incontact with each other. A special fluid called index matching gel (or oil) isoften added to the splice to fill the air gap between the fiber ends andreduce Fresnel reflections. Rotary and Fiberlok are two examples ofmechanical splices. Mechanical splices are simple, install quickly, and have

relatively low loss. They are typically used to restore damaged cables and inaerial applications where fusion techniques would be impractical.



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6.2.2.2 Fusion Splicing Method

Fusion splices are formed by welding two cleaved fiber ends together in apermanent union - they have the lowest loss of the three methods and

produce extremely low reflections (see Figure 9). Fusion splices are mostoften used to construct and restore permanent cable runs.

Fusion Splicing machine

Picture of Splicing going



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and field cleaver for multimode applications. A mirror like almost perfect endface is achieved by this cleaving process.

3. Fiber alignment

The fibers are laterally aligned to each other by step motor in a fusion splice.This may involve rotating the fibers in polarization maintaining fiber splicing.

4. Fiber weldingThe fibers are then heated with electric arc or other methods to the fiberglass's softening point and then both fibers are pressed together to form asolid joint.

5. Insertion loss estimationthe insertion loss is estimated based on the fusion quality and dimensions.

6. Pull tension strength testingThe fusion is pull proof tested when opening the fusion splice cover.

7. Splice protection with fusion splice sleeveThe fusion splice joint is then protected with a heat shrink tube with a steelstrength member inside to form a solid and reliable fiber joint.

6.2.3 Connector

Connectors provide fiber optic junctions that can be disconnected andreconnected as necessary. They are adaptable, convenient and are typically

used at patch panels and for electronic systems and test equipment.Installing a connector requires special tools and training.The “ferrule” is the protruding connector part that houses the fiber andnormally includes a spring that provides axial pressure when two connectorsare mated. The end face of the fiber/ferrule is finished (polished) to minimizereflections from the mating surfaces. Each surface of the plane polishedferrule reflects about 4% of the light incident upon it. In coherent systems,the total reflection can be as high as 15%, or it can be made extremelylow. I no amount or refraction clemencies on me gap between the ends tothe timbers, the cleave and the quality of the polish.Physical contact (PC) connectors use a rounded polish to better ensure that

the ends of the fiber make contact without a gap. This reduces the reflectionfrom the connection and improves measurement repeatability. If the end ofthe fiber is polished at an angle, the reflected light will be directed intounguided modes (light paths that don’t travel very far) and light will be lostfrom the fiber. This results in very low reflectance for guided modes. Somemanufacturers improve on this design even more by polishing the ends ofthe fibers into angled hemispheres.



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Different types of connectors are use in optical fiber communication system.

Some types of connector name and picture are given bellows which are

broadly used



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6.3 Termination of opt ical fiber cable

An optical fiber termination in which a plastic clad optical fiber is pushed intoa heated ferrule containing a pierced watch bearing jewel so as to force the

bare fiber through the aperture in the jewel. The protruding fiber end is thenfused and polished flush with the jewel whereby the fiber end is centeredwithin the jewel aperture.

Terminate fiber optic cable two ways - with connectors that can mate twofibers to create a temporary joint and/or connect the fiber to a piece ofnetwork gear or with splices which create a permanent joint between the twofibers. These terminations must be of the right style, installed in a mannerthat makes them have little light loss and protected against dirt or damage inuse. No area of fiber optics has been given greater attention thantermination. Manufacturers have come up with over 80 styles of connectors

and and about a dozen ways to install them. There are two types of splicesand many ways of implementing the splice. only a few types are used mostapplications. Different connectors and splice termination procedures areused for single mode and multimode connectors, so make sure know whatthe fiber will be before specify connectors or splices

6.4 Optical distribution frame (ODF)

For optical fiber cable termination need box for joint and cable distribution iscalled optical distribution frame (ODF).This optical distribution frame containoptical fiber connector.

ODF



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6.4 Patch Cord

Optical Patchord so called fiber cable assembly is connector terminated both ends and ready for

installation. Plank offer full-range of optic fiber Patchcords at FC, SC, ST* - PC, UPC or APC

connectivity. All our patch products come with Low insertion loss, Low return loss,

Environmentally stable and reliable, precise dimension and wide selection of ferrules.

FC - FC patch cord, Duplex, PC/UPC/APC, Single / Mult iMode

A flexible piece of duplex cable terminated at both ends with FCconnector. Used for interconnecting circuits on a patch board, in a wiringcloset, or at the work area. FC single / multi mode, UPC/APC polish, anylength available higher quality.

SC - SC patch cord, Duplex, PC/UPC/APC, Single / MultiMode

A flexible piece of duplex cable terminated at both ends with SCconnector. Used for interconnecting circuits on a patch board, in a wiringcloset, or at the work area. FC single / multi mode, UPC/APC polish, anylength available higher quality.

LC - LC patch cord, Duplex, PC/UPC/APC, Single / MultiMode

A flexible piece of duplex cable terminated at both ends with LCconnector. Used for interconnecting circuits on a patch board, in a wiringcloset, or at the work area. LC single / multi mode, UPC/APC polish, anylength available higher quality.

ST - ST patch cord, Duplex, PC/UPC/APC, Single / MultiMode

A flexible piece of duplex cable terminated at both ends with STconnector. Used for interconnecting circuits on a patch board, in a wiringcloset, or at the work area. ST single / multi mode, UPC/APC polish, anylength available higher quality.

E2000 - E2000 patch cord, Duplex, PC/UPC/APC, Single/ Multi Mode

A flexible piece of duplex cable terminated at both ends with E2000connector. Used for interconnecting circuits on a patch board, in a wiringcloset, or at the work area. E2000 single / multi mode, UPC/APC polish,any length available higher quality.



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MTRJ - MTRJ patch cord, Duplex, PC/UPC/APC, Single /Multi Mode

A flexible piece of duplex cable terminated at both ends with MTRJ

connector. Used for interconnecting circuits on a patch board, in a wiringcloset, or at the work area. MTRJ single / multi mode, UPC/APC polish,any length available higher quality.

LC - SC patch cord, Duplex, PC/UPC/APC, Single / MultiMode

A flexible piece of cable terminated with SC connector at one side andwith with LC connector another side. Used for interconnecting circuits ona patch board, in a wiring closet, or at the work area. SC/LC single/ multi mode, UPC/APC polish, any length available higher quality.

LC - FC patch cord, Duplex, PC/UPC/APC, Single / Mult iMode

A flexible piece of cable terminated with FC connector at one side andwith with LC connector another side. Used for interconnecting circuits ona patch board, in a wiring closet, or at the work area. SC/LC single/ multi mode, UPC/APC polish, any length available higher quality.

SC - FC patch cord, Duplex, PC/UPC/APC, Single / MultiMode

A flexible piece of cable terminated with FC connector at one side and

with with SC connector another side. Used for interconnecting circuits ona patch board, in a wiring closet, or at the work area. SC/FC single/ multi mode, UPC/APC polish, any length available higher quality.

ST - FC patch cord, Duplex, PC/UPC/APC, Single / MultiMode

A flexible piece of cable terminated with FC connector at one side andwith with ST connector another side. Used for interconnecting circuits ona patch board, in a wiring closet, or at the work area. ST/FC single/ multi mode, UPC/APC polish, any length available higher quality.

FC-MTRJ patch cord, PC/UPC/APC, Single / Multi Mode A flexible piece of cable terminated with FC connector at one side andwith with MTRJ connector another side. Used for interconnecting circuitson a patch board, in a wiring closet, or at the work area. FC/MTRJ single/ multi mode, UPC/APC polish, any length available higher quality.



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E2000-MTRJ patch cord, PC/UPC/APC, Single / MultiMode

A flexible piece of cable terminated with E2000 connector at one

side and with with MTRJ connector another side. Used forinterconnecting circuits on a patch board, in a wiring closet, or at thework area. E2000/MTRJ single / multi mode, UPC/APC polish, anylength available higher quality.

LC - ST patch cord, Duplex, PC/UPC/APC, Single / MultiMode

A flexible piece of cable terminated with ST connector at one side andwith with LC connector another side. Used for interconnecting circuits ona patch board, in a wiring closet, or at the work area. ST/LC single/ multi mode, UPC/APC polish, any length available higher quality.

LC - E2000 patch cord, Duplex, PC/UPC/APC, Single /Multi Mode

A flexible piece of cable terminated with E2000 connector at oneside and with with LC connector another side. Used for interconnectingcircuits on a patch board, in a wiring closet, or at the work area. ST/LCsingle / multi mode, UPC/APC polish, any length available higher quality.

SC - ST patch cord, Duplex, PC/UPC/APC, Single / MultiMode

A flexible piece of cable terminated with ST connector at one side andwith with SC connector another side. Used for interconnecting circuits ona patchboard, in a wiring closet, or at the work area. SC/FC single/ multi mode, UPC/APC polish, any lenght available higher quality.

SC - E2000 patch cord, Duplex, PC/UPC/APC, Single /Multi Mode

A flexible piece of cable terminated with E2000 connector at oneside and with with SC connector another side. Used for interconnectingcircuits on a patch board, in a wiring closet, or at the workarea. SC/E2000 single / multi mode, UPC/APC polish, any lenghtavailable higher quality.

ST - E2000 patch cord, Duplex, PC/UPC/APC, Single /Multi Mode

A flexible piece of cable terminated with E2000 connector at oneside and with with ST connector another side. Used for interconnectingcircuits on a patch board, in a wiring closet, or at the workarea. ST/E2000 single / multi mode, UPC/APC polish, any lenght



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available higher quality.

FC - E2000 patch cord, Duplex, PC/UPC/APC, Single /

Multi Mode A flexible piece of cable terminated with E2000 connector at oneside and with with FC connector another side. Used for interconnectingcircuits on a patch board, in a wiring closet, or at the workarea. FC/E2000 single / multi mode, UPC/APC polish, any lenghtavailable higher quality.

SC-MTRJ patch cord, PC/UPC/APC, Single / Multi Mode

A flexible piece of cable terminated with SC connector at one side andwith with MTRJ connector another side. Used for interconnecting circuitson a patch board, in a wiring closet, or at the work area. SC/MTRJ single

/ multi mode, UPC/APC polish, any length available higher quality.

ST-MTRJ patch cord, PC/UPC/APC, Single / Multi Mode

A flexible piece of cable terminated with ST connector at one side andwith with MTRJ connector another side. Used for interconnecting circuitson a patch board, in a wiring closet, or at the work area. ST/MTRJ single/ multi mode, UPC/APC polish, any length available higher quality.

LC-MTRJ patch cord, PC/UPC/APC, Single / Mult i Mode

A flexible piece of cable terminated with LC connector at one side and

with with MTRJ connector another side. Used for interconnecting circuitson a patch board, in a wiring closet, or at the work area. LC/MTRJ single/ multi mode, UPC/APC polish, any length available higher quality.

Customized: YOU choose - YOU choose patch cords,Duplex, PC/UPC/APC, Single / Multi Mode

A custom-made at your request piece of cable terminated with YOURSELECTED connector at one side and withwith YOUR SELECTED connector another side. Used forinterconnecting circuits on a patch board, in a wiring closet, or at thework area. Customized for your case single / multi mode, UPC/APC

polish, any length available higher quality.



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Discussion

Optical fiber is hallow plastic or glass fiber which carries light wave.In modern telecommunication system optical fiber has become a vitaltransmission media. Optical fiber has enormous bandwidth (1014) which cancarry millions of data and signals at a time. When analyzing it was observedthat the system economic and technically feasible, In the optical fiber systemloss is very much (0.92 dB/Km) negligible when compared with other datatransmission system.

After completion of this thesis work it is felt that we have been able toacquire more practical knowledge about optical fiber communication system,like as how to do the trance laying duct, duct integration test cable jettingcable splicing & termination the cable. This achievement of practicalknowledge will help us in future implement the system with less problems. Itis possible to implement this optical fiber communication system in field levelby acquired knowledge. We fill confident for knowing the system elaboratelybe able to apply in modern telecommunication system.



REFERENCE

1. Optical fiber communication principles and practice John M. Senior

2. Training ManualDuraline – Plumettaz Academy

3. WikipediaFrom Internet

Transmission in Optical Fiber Communication

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Transcript of Transmission in Optical Fiber Communication