bsnl internship ppt

1. A summer training presentation
on
“ telecommunication”
By
Ravi Kumar
Mishra

2. BSNL Overview
BSNL is India's oldestand largestcommunicationservice provider (CSP).
It had a customer base of 110 million as of June 2013. It has footprints
throughout India except for the metropolitan cities of Mumbai and New
Delhi, which are managed by MahanagarTelephone Nigam (MTNL).
When it comes to connecting the four corners of the nation, and
much beyond, one solitary name lies embedded at the pinnacle -
BSNL. A company that has gone past the number games and the
quest to attain the position of a leader . It is working round the
clock to take India into the future by providing world class telecom
services for people of India. BSNL is India's no. 1 Telecom Service
provider and most trusted Telecom brand of the Nation.

3. Services provided by BSNL
Universal Telecom Services
Cellular MobileTelephoneServices
WLL-CDMATelephoneServices
Internet
Intelligent Network (IN)
3G services
IPTV
FTTH
Helpdesk
WiMax

4. What is telecommunication?
telecommunication is the exchange of information, messages, pictures
etc from one point to another distant point as per desire of the user and
under the control of some system.
Telecommunication is the assisted transmission of signals over a
distance for the purpose of communication.
Telecommunication medium
Anything that carries an electronic signal and interfaces between a sending
device and a receiving device.

5. What is GSM ?
Global System for Mobile (GSM) is a second generation cellular standard
developed for voice services and data delivery using digital modulation
GSM Services
• Tele-services
• Data Services
• Supplementary services

6. Tele Services
• Telecommunication services thatenablevoicecommunication
via mobile phones
• Offered services
- Mobile telephony
- Emergency calling

7. Data Services
⚫Include various data services for information transfer
between GSM and other networks like PSTN, etc at rates
from 300 to 9600 bps
⚫Short Message Service (SMS)
⚫up to 160 characteralphanumericdata transmission
to/from the mobile terminal
⚫Unified Messaging Services(UMS)
⚫ fax
⚫Voice mailbox
⚫Electronic mail

8. GSM System Architecture
BSC
BSC
MSC
MS
MS
MS BTS
BTS
BTS EIR
AUC
HLR
VLR

9. Advantages of GSM over Analog system
⚫Capacity increases
⚫Reduced RF transmission powerand longer battery life.
⚫International roaming capability.
⚫Bettersecurityagainst fraud (through terminal validation
and userauthentication).
⚫Encryption capability for information securityand privacy.
⚫Compatibilitywith ISDN,leading to wider range of services

10. CDMA
⚫MultipleAccess in CDMA:
⚫Each user isassigned a unique PN code.
⚫Each user transmits its information by spreading with
uniquecode.
⚫Direct Sequence spread spectrum is used.
⚫Users are separated bycode not by timeslot and freq
slot.

11. CDMA
⚫Conceptof CDMA
Users share same
bandwidth
Useraxis shows
cumulativesignal strength
of all users
Code 4
Code 3
Code2
Code 1
Freq
User

12. CDMA
⚫Spread Spectrum and MultipleAccess:
⚫Spread Spectrum
⚫ In Spread spectrum data is transmitted with BW in excess to
minimum BW necessaryto send it.
⚫ Spread spectrum is achieved by spreading with PN code at
transmitter . Same code is used todispread thereceived signal
at receiver
⚫How do we get increased spectrum
X
input signal
Wide band
code seq
Narrow band Wide band
Spreaded seq

13. CDMA
Code 4
Code 3
Code2
Code 1
Freq
⚫Advantages of spread spectrum:
⚫ Multipath Rejection
⚫ Immunity to interference and jamming
⚫ Multiple access
User

14. OPTICAL FIBER
• The main objectof optical fiber is toguide lightwaves
with minimumof attenuation(lossof signal).
• It is composed of fine threadsof glass in layercalled
coreand cladding.

15. PRINCIPLE OF OPTICAL FIBER
• It’sworkson total internal reflection with in a fiber
core.
• Thecore has higher refractive index then then
cladding.
• The beam thatstrikes the surfaceat more then the
critical angel to be reflected.

16. Introduction (Cont…)
⚫Core – thin glasscenterof the fiberwhere light travels.
⚫Cladding – outeroptical material surrounding the
core
⚫ BufferCoating – plastic
coating that protects
the fiber.

17. Type of Fibers
Optical fibers come in two types:
⚫Single-mode fibers – used to transmit onesignal per
fiber (used in telephone and cable TV). They have
small cores(9 microns in diameter) and transmit
infra-red light from laser.
⚫Multi-mode fibers – used to transmit many signals
per fiber (used in computer networks). They have
larger cores(62.5 microns in diameter) and transmit
infra-red light from LED.

18. Advantages of Optical Fibre
Thinner
Less Expensive
Higher Carrying Capacity
Less Signal Degradation& Digital Signals
Light Signals
Non-Flammable
Light Weight

19. BROADBAND TECHNOLOGY
It indicatesa meansof connectivityata high or
“broad” bandwidth. There are various ways to
define the broadband:-
• Provides signal switched facilityoffering integrated
access to voice,data,vadeo and interactive delivery
service.

20. BROADBAND TECHNOLOGY
TYPES
• Itcan bedivided in to following categories:
• Wire line technology
• Wirelesstechnology

21. WIRELINE TECHNOLOGY
• Digital subscriber line(DSL) on copper loop
• Optical fiber technology
• CableTV networking
• PLC(power line communication)