GSM Overview with pratical call setups

7/30/2019 GSM Overview with pratical call setups

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By saurabh ShuklaBT ET 69

Base Station SystemBSS

Located at MTNL Shadipur Switch.


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About MTNL BSS ( Shadipur )

MTNL is a leading Public sector player in telecomdomain.

It provides fixed line,

mobile and internet

services.

The exchange at shadipur

( Delhi ) covers a wide area

and catersto almost 75k Users.


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About MTNL BSS ( Shadipur )

It houses the BSS, which is responsible forcontrolling GSM mobile operations in thecell at or near shadipur, karol bagh area.

They have installed BTS , VLR , HLR andother subsytem from reputed firms likeHuawei , Alcatel and Motorola.

These high performance systems do allnecessary operation so that order andstability is maintained throughout the

system.


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What is GSM?

Generation of GSM

Fundamental of GSM

Architecture of GSM

BSS and its components.

Topics Covered


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The Global System for Mobile communications

is a digital cellular communications system.

It was developed in order to create a commonEuropean mobile telephone standard but it has

been rapidly accepted worldwide.

GSM was the brainchild of Bell labs ( US ).

What is GSM ?


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Generations of GSM1st generation:- Analog mobile technologies

2nd generation:- digital mobile technologies :- GSM ,

CDMA

2.5generation:- Enhancement of GSM:- GPRS

3rd generation:- 3G mobile telephony


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GSM STANDARDS

GSM-900 Standard

The GSM-900 standard is a standard fordigital voice transmission in the 900 MHzband.

GSM-1800 Standard

In GSM-1800, 1800 MHz band was allocatedfor digital mobile telephone services

GSM-1900 Standard

GSM-1900 is the standard for the 1900MHzband.


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GSM Multiplex structure

GSM works on a combination of FDM andTDM for providing multiple access.

GSM utilizes a cellular concept, in which a

geographical area is divided into planned radiocells .

It Provides one BTS per cell with which amobile can make contact.

The cell radius can vary according to user

density from 300 mtrs to 35 Kms.


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BSS ( Base Station System )

Comprises of two main components : -

BTS

BSC


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BSS ( Base Station System )

The BSS is a set of BS equipments that areresponsible for communicating with MS's in a

certain area.

The BSS includes two types of machines: theBTS in contact with the MS's through the

radio interface and the BSC, the latter being

in contact with the MSC.

A BTS transmits and receives radio signal

from a mobile interface.

A BSC is a component that functions for the

control of one or more BTS.


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Mobile station(MS)

It represents the terminal equipment used by thewireless subscriber supported by the GSM Wirelesssystem.

SIM (Subscriber identity Module) - It is basically a

removable smart card .It includes a microprocessorwith all the subscriber-related information .

At MTNL MS can be any cellular device that uses

SIM card.

Each BTS controls many MSs.


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BTS ( Base Transciever Station)

BTS is a network element withtransmission and reception devices(transceivers) to and from the MS.

It can be considered as a complex radiomodem controlled by the BSC.

Multiplex the information to be

transmitted over each carrier. Responsible for frequency hoping


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Live BTS Transceiver


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BSC ( Base System Controller )

A BSC is a network component in thePLMN that function for control of one ormore BTS.

Control and supervise the

BTSs. The fig shows a BSC.

Manages traffic and supervises

congestion and sometimes eases it.


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ConclusionFrom this presentation I arrive at a conclusion thatGSM is a very economic mobile telephony system andalso it provides flexibility and portability.

The BSS at MTNL Shadipur is a state of the art basestation system providing high end mobile services to

the masses.

GSM Overview with pratical call setups

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