Department of E&TC Engineering Academic Year:-2015-16 Semester:-II

“MOBILE TELEPHONE SWITCHING CENTRE- BSNL”

on

7th MARCH 2016

Resource Person

Coordinator Prof. Madan Veer

Department of Electronics &

Industrial Visit Report

Date:07 /03/2016 To, The Principal, D.Y. Patil College of Engineering, Ambi , Pune.

Subject: “Mobile Communication” industrial visit Report Respected Sir,

We had organized an Industrial Visit on “Mobile Communication” on 7th March,2016.The main objective of the Industrial Visit was to get interact with the expert in the field & explore the fundamentals of mobile switching centre and achievements of BSNL. The details of “Industrial Visit” are as follows: Resource Person Mr.Bamane Organization/Institute BSNL Mobile Switching Centre,Chinchwad, Pune. Cell No 9028710202 Subject Mobile Communication Class BE Date 7th to 8th March.2016. Time 9.30 PM- 3:30 PM Topic Covered Global System For Mobile System,Mobile Switching Centre,Details Of Power Supply,Base Station Controller,Base Transceiver Station,Home Location Register,Visit Location Register,Switching Functions Of Mobile System,Working Principles Of Mobile System etc. Present No. of Students 55

Thanking you.

Dr. R. P. Borole HOD, E&TC Encl: 1. Purpose Of Visit 2. Achievements Of BSNL 3. Introducing BSNL 4. Power Supply 5. Global System For Mobile 6. Snap shots(Digital Copies sent by mail)

1.Purpose Of Visit

On the occasion of science day,the nearly 55 students and two teaching and non-teaching staff of DYPCOE have visited Bharat Sanchar Nigam Limited on 7th March,2016.

The initial phase of telecom reforms began 1984 with operation of central centre for department of telematrics(C-DDT) for developing indigenous technologies and private manufacturing of customer premise equipment.soon after,the Mhanagar Telephone Nigam Limited(MTNL) and Videsh Sanchar Nigam Limited(VSNL) were getup in 1986.the telecom comission was established in 1989.a crusial aspect of the institutional reform of the Indian Telecom Sector was setting up of an independent regulatory body in 1998.the Telecom Regulatory Authority Of (TRAI) to assure investors that the sector would be regulated in a balanced.In 2000 DOT corporatized its service and creating Bharat Sanchar Ngam Limited.

2. Achievements Of BSNL

BSNL has customer base over a core and 15 the fourth largest integrated telecom operator in the country.

BSNL in the market leader in broadband landline and national transmission network.BSNL is also the only operator covering over 5 lakh village with telecom connectivity area of operation of BSNL is all India except & .

3.Introducing BSNL

GSM:

Global System for Mobile(GSM) is a second generation cellular standard developed to cater voice services and data recovery using digital modulation.

GSM Services

Teleservices:

Telecommunication services that voice communication via mobile phones.

Offered Services

•

• Emergency Calling

Bearer Services:

Include various data services for information transfer between GSM and other networks like PSTN,ISDN etc at rates from 300 to 9600Bps.

Short Message Services:

Upto 160 character alphanumeric data transmition to from the mobile terminal.

• voice mailbox

• electronic mail

Supplementary Services:

Call related services-

• Call waiting

• Call hold

• Call barring

• Call forwarding

• Multi party call conferencing

• Caller line identification presentation

• Caller line identification restriction

• Closed user group

4. Power Supply Room: First we went power supply room was devided into two rooms.1st room had 440v Ac 3phase supply which was given to SMPS in reverse manner like negative was given to positive and vice versa and constant 54v/200A was drawn from SMPS set of SMPS were used and all were connected in parallel.the individual oad capacity of a in parallel.the individual load capacity of SMPS was 65v/200A,but due to parallel connection the load capacity gets distributed and total supply drawn 65v/570A from 600v/2400A. In 2nd room the series connection from SMPS was given to VRLA batteries for backup if main supply fails VRLA batteries ued because they does not allow to escape qas from battery container and there load capacity was 3000AH.in power supply room everything was double from SMPS to battery,to prevent the system down due to power failure,if any single supply fails,second will keep the system.

5. Global System For Mobile

System Archietechture Mobile Station(MS)

The mobile station is made up of two entities Mobile Equipment(ME) and Subscriber Identity Module(SIM).

1.Mobile Equipment

• Portable,vehicle mounted,hand held device

• Uniquely Identified by an IMEI(Internet Mobile Equipment Identity)

• Voice and data transmission

• Monitoring power and signal quality of surrounding cells for optimum handover

• Power level-0.8wto20w

160 character long SMS

System Architechture Base Station Subsystem

Base station subsystem is composed of two parts that communication across the standars Abis interface allowimg operation between components made by different suppliers.

Authentication Centre(AUC)

Protects against intruders air interface.maintains authentication keys and algorithm and provides security triple.

Equipment Identity Register(IER)

Database that is used in track handset is using the IMEI(International Mobile Equipment Identity).made up of three subclasses –

• The white list:list of valid mobile equipment

• The black list:list of mobile for which services offered

• The gray list:list of suspected mobile under observation.

GSM Specification-

GSM 900:

Uplink : 890-915Mhz

Downlink : 935-960Mhz

B.w:2.25Mhz

GSM 1800:

Uplink : 1710-1785Mhz

Downlink : 1805-1880Mhz

B.w : 2.75Mhz

Home Location Register(HLR):

Permanent database about mobile subscribe in large service area

Visitor Location Register(VLR):

Temporary database which update whenever new MS enters its area,by HLR database.

Base Transreceiver Station(BTS):

• Encode,encrypts,multiplexers,modulates and feeds the RF signals to the antenna.

• Frequency hopping.

• Communicate with mobile station and BSC.

• Consists of transreceiver station.

Base Station Controller(BSC):

• Manage radio resources for BTS.

• Assigns frequency and time slots for all MS in its area.

• Handles call setup.

• Transcoding and Rate adaption functionality.

• Handover for each MS.

Mobile Switching Centre:

• Heart of the network.

• Manages communication between GSM and other networks.

• Call setup function and basic switching.

• Call Routing.

• Billing information and collection.

Snap shots (Digital Copies sent by mail)

1.Snap Shots: