Telecom Cables: OFC Is In

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With an increase in the number of private operators in basic, cellular, and DLD,
there has been an increase in the demand for optical fiber cable (OFC) in the

country. Service providers as well as utility public sector companies have been

deploying OFC in large quantities. In future, polyethylene insulated

jelly-filled (PIJF) cable requirement is going to come down with the increase in

usage of fiber and other wireless technologies.

Polyethylene insulated jelly-filled cable (PIJF): PIJF

is an assembly of a number of pairs of copper wires. The gap between the pairs

of wires is filled with petroleum jelly to reduce noise and transmission losses.

Each line has two wires–one for incoming and the other for outgoing.

Prior to 1980, DoT was using paper covered unit twined (PCUT)

dry core cables. The primary cable had to be protected from moisture. With the

introduction of PIJF cable, DoT took a decision to discontinue the use of PCUT

cable. There are two types of PIJF cables in use–solid PIJF cable and foamed

PIJF cable. In case of the solid PIJF cable, the conductor is insulated with

solid polyethylene. This type of cable is presently used in the DoT network. In

case of foamed PIJF cable, the conductor insulation is foamed to form a cellular

cross-section, with a suitable foaming agent.

Optical Fiber Cables (OFC): OFC offers almost

unlimited bandwidth and unique advantages over all previously developed

transmission media. OFCs are no longer dominant only in the transport network or

feeder line but have penetrated to a large extent in the subscriber loop as

well. With fiber, one can transmit narrowband, wideband and broadband

communication services to the end-subscriber through POTS, ISDN phone, video

phone, and video-conferencing. To supply all these services with data rates up

to 2.5 Gbps, single mode fiber pair is necessary.

Following are the advantages of OFC over other transmission

systems:

• The ability to carry much more information and deliver it
  
  with greater fidelity than the copper or coaxial cable

• OFC can support much higher data rates and at greater
  
  distances than coaxial cable

• OFC is immune to all kinds of interferences, including
  
  lightning and will not conduct electricity even if it comes in direct
  
  contact with high-voltage electrical equipment and power lines

• As an optical fiber is made of glass, it will not corrode
  
  and is unaffected by most chemicals

• An OFC, even the one containing many fibers, is much
  
  thinner and lighter in comparison to coaxial cable with a similar
  
  information carrying capacity. It is easier to handle and install, and uses
  
  less duct space

• OFC is ideal for secure communication systems because it
  
  is very difficult to tap but very easy to monitor.

Buying Tips

Pricing: The key buying parameter in government (BSNL, MTNL,

and Indian Railways) tenders is the price as long as the optical fiber cables

meet the required specifications. On the other hand, the private operator, which

contributes a small portion of the overall OFC sales in the country, pays more

stress on the quality of fiber.

While buying optical fiber cables, carriers and enterprise

customers should focus more on optical parameters, as most of the problems are

due to impurity of glass.

Dispersion Slope: Different fiber manufacturers have

different dispersion slopes, which is proprietary. Different OFC manufacturers

in the country use different standards, which is just a marketing gimmick used

by manufacturers. Lower the dispersion slope, the better it is.

End-to-End Attenuation: The reduction in signal

strength is measured as attenuation and the unit is decibels (dB). The light

passing through fiber will not disperse if the fiber cladding is uniform

throughout the length of the fiber. So attenuation loss can be minimized if

there is uniformity. The permissible limit for 1,310 nm is 0.38 dB/km while for

1,550 nm it is 0.22 dB/km.

If the attenuation level decreases, it is good, but if it

increases then one has to increase the number of repeaters, which will result in

an increase in transmission cost. In majority of fibers, the attenuation loss

varies from 0.19 dB/km to 0.33 dB/km and there is an increase of 0.01 dB/km once

the fiber is transformed into OFC.

Attenuation Under Stressful Condition: Under this condition,

OFC is put under stress and the cable is tied on either side, and 2.7 Newton

weight is applied on both the sides. The maximum attenuation variation should be

0.4 to 0.5 percent. Once OFC is relaxed, it comes back to the normal position.

Under pressure, the cable should not break. This is used mainly for duct and

buried type of OFC.

The buyer should also look at other mechanical and optical

properties like mode field concentricity (shows how uniform an OFC is), cut-off

wavelength, splice loss, and fiber loss per km (dependent on the transmission

equipment).

Polarized Mode Dispersion: This tests the optical

characteristics of OFC in polarized mode whereby one can test how much light

goes out and how much light remains inside the fiber.

Chromatic Dispersion: It depicts the number of wavelength

that is attenuated and the strength of the signal.

Market Information

The large-scale deployment of cables by carriers has given a

big boost to the telecom cable industry in India. Suddenly, all types of

carriers, from basic service providers, cellular service providers, domestic

long-distance service providers, and ISPs, to utility service providers like

GAIL, PCIL, and Indian Railways, have been deploying telecom cables in large

numbers, in a number of locations.

The Indian telecom cable market is estimated at Rs 4,317.51

crore (excluding the cables that have been imported) for 2000-01. In 1999-2000,

the telecom cable industry was valued at Rs 3,685.31 crore (revised from the

earlier figure of Rs 4,000 crore published in the July 2000 issue of

VOICE&DATA). The excellent performance of the industry can be attributed to

an increase in plant utilization, remunerative prices fixed by BSNL, and

buoyancy in prices of raw materials like copper and fiber.

The industry has achieved a growth of 17.15 percent in

2000-01. On the OFC front, cable manufacturers have imported cables from the

worldwide market, as there was a shortage in the Indian market. However, the

jelly-filled telecom cable (JFTC) market was entirely taken care of by the

Indian manufacturers.

On one hand, Hindustan Cables was the No 1 player on the JFTC

front, followed by Sterlite and Finolex. On the other hand, Sterlite Optical was

the No 1 player on the OFC front, followed by Aksh and Hindustan Cables.

The total OFC market, in terms of rkm, for the fiscal

2000-01, was 2,55,000, which catered to the Indian market as well as to the

export market, whereas the total JFTC market in India was estimated to be 638

lakh cable kilometer (lckm)

Public sector units like BSNL and MTNL are still the bulk

buyers of JFTC and OFC cables in the country. But of late, private players have

begun to source cables in a big way.

Seeing a huge opportunity in the telecom cable market, many

new entrants like Enigma, National Cables, Reliance Engineers, Uniflex, and West

Coast have started cable manufacturing setups in different regions of the

country.

Despite the huge demand in the fiber cable market, the

industry is facing a shortage in terms of raw materials. So on the OFC front,

companies have started doing backward integration by setting up preform and

fiber drawing factories.

The demand for fiber outstripped the supply, and the shortage

of fiber worldwide and in the Indian market led to an increase in the cost of

optical fiber cable and fiber in the market. The cost of drawn fiber reached a

peak of Rs 5,500 per km and is presently hovering around Rs 4,700 per km.

This year, BSNL is planning to go for distributed switching

technology that will help optimization on the JFTC cable network. The plan

outlay for BSNL in 2001-02 is to deploy 473 lckm of JFTC and if possible, to cut

down on lckm. This translates into a drop of around 19 percent.

Since it is warding-off competition from Reliance, BSNL is

very aggressive on the infrastructure side. The company has already given an

order worth 441 lckm of JFTC cable, this fiscal. MTNL has also come up with a

tender for 17 lckm this fiscal. On the OFC front, the company has floated a

tender for 1,00,000 rkm.

This year, there will be an increased requirement of telecom

cable from Reliance Infocom, Hughes Tele.com, Bharti, Tata Teleservices, Shyam

Telelink, and HFCL Infotel. This year, the private basic service providers will

deploy around 100 lckm of PIJF cables and around 30,000 rkm of OFC in the

country, whereas BSNL is planning to deploy 126,000 rkm, an increase of 26

percent from the previous year’s planning. But in terms of actual deployment,

the growth translates to a whopping 133 percent.