1. A summer training presentation
on
“ telecommunication”
By
Saroj choudhary

2. BSNL Overview
BSNL is India's oldest and largest communication service 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 Mahanagar Telephone 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 Mobile Telephone Services
WLL-CDMA Telephone Services
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 that enable voice communication
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 character alphanumeric data transmission
to/from the mobile terminal
 Unified Messaging Services(UMS)
 fax
 Voice mailbox
 Electronic mail

8. Supplementary Services
Call related services :
• Call Waiting- Notification of an incoming call while on the handset
• Call Hold- Put a caller on hold to take another call
• Call Barring- All calls, outgoing calls, or incoming calls
• Call Forwarding- Calls can be sent to various numbers defined by the user
• Multi Party Call Conferencing - Link multiple calls together
• CLIP – Caller line identification presentation
• CLIR – Caller line identification restriction
• CUG – Closed user group

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

10. Advantages of GSM over Analog system
 Capacity increases
 Reduced RF transmission power and longer battery life.
 International roaming capability.
 Better security against fraud (through terminal validation
and user authentication).
 Encryption capability for information security and privacy.
 Compatibility with ISDN,leading to wider range of services

11. GSM Applications
 Mobile telephony
 GSM-R
 Telemetry System
- Fleet management
- Automatic meter reading
- Toll Collection
- Remote control and fault reporting of DG sets
 Value Added Services

12. Future Of GSM
 2nd Generation
 GSM -9.6 Kbps (data rate)
 2.5 Generation ( Future of GSM)
 HSCSD (High Speed ckt Switched data)
 Data rate : 76.8 Kbps (9.6 x 8 kbps)
 GPRS (General Packet Radio service)
 Data rate: 14.4 - 115.2 Kbps
 EDGE (Enhanced data rate for GSM Evolution)
 Data rate: 547.2 Kbps (max)
 3 Generation
 WCDMA(Wide band CDMA)
 Data rate : 0.348 – 2.0 Mbps

13. CDMA
 Multiple Access in CDMA:
 Each user is assigned a unique PN code.
 Each user transmits its information by spreading with
unique code.
 Direct Sequence spread spectrum is used.
 Users are separated by code not by time slot and freq
slot.

14. CDMA
 Concept of CDMA
 Users share same
bandwidth
 User axis shows
cumulative signal strength
of all users
Code 1
Code2
Code 3
Code 4
Freq
User

15. CDMA
 Spread Spectrum and Multiple Access:
 Spread Spectrum
 In Spread spectrum data is transmitted with BW in excess to
minimum BW necessary to send it.
 Spread spectrum is achieved by spreading with PN code at
transmitter . Same code is used to dispread the received signal
at receiver
 How do we get increased spectrum
X
Narrow band
input signal
Wide band
code seq
Wide band
Spreaded seq

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

17. OPTICAL FIBER
• The main object of optical fiber is to guide light waves
with minimum of attenuation(loss of signal).
• It is composed of fine threads of glass in layer called
core and cladding.

18. PRINCIPLE OF OPTICAL FIBER
• It’s works on total internal reflection with in a fiber
core.
• The core has higher refractive index then then
cladding.
• The beam that strikes the surface at more then the
critical angel to be reflected.

19. TOTEL INTERNAL REFLECTION

20. Introduction (Cont…)
 Core – thin glass center of the fiber where light travels.
 Cladding – outer optical material surrounding the
core
 Buffer Coating – plastic
coating that protects
the fiber.

21. How Does Optical Fibre Transmit
Light??
 Total Internal Reflection.
 Fibre Optics Relay Systems has
-Transmitter
-Optical Fibre
-Optical Regenerator
-Optical Receiver

22. Type of Fibers
Optical fibers come in two types:
 Single-mode fibers – used to transmit one signal 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.

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

24. Areas of Application
Telecommunications
Local Area Networks
Cable TV
CCTV
Optical Fiber Sensors

25. BROADBAND TECHNOLOGY
It indicates a means of connectivity at a high or
“broad” bandwidth. There are various ways to
define the broadband:-
• Provides signal switched facility offering integrated
access to voice,data,vadeo and interactive delivery
service.

26. BROADBAND TECHNOLOGY
TYPES
• It can be divided in to following categories:
• Wire line technology
• Wireless technology

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

28. WIRELESS TECHNILOGY
• Satellite Media
• Terrestrial Wireless
• 3G Mobile
• Wi-Fi(Wireless Fidelity)
• WiMax

29. GPRS
General Packet Radio Service
GSM Service for end-to-end packet switching
Reuse of existing infrastructure
Works with existing Circuit-Switched serve.

30. GPRS user Benefits
-Higher speeds
– Global access
– Fast access time
– Cost efficient
– Convenient

32. Questions ?