Transcript

A Scenario of Mobile Communications in

hazardous situations and physical disasters

by

Mr. Alexander Soulahakis

Supervisor

Prof. Madjid Merabti

Overview

Objectives• Scenario• Theory GSM• Design Decisions• 802.11 Wireless Lan• SMS without

network support• Experiment – Phases• Conclusions

•Papers

•Standards

•Books

•Books Wireless Lan

•Books GSM

•Mobile Radio Networks

•Caution Project

•Tools / Simulator Manuals

Literature Review

Objective of the project

• The scope of the project is an alternative way of GSM communications, by proposing Ad hoc networking and 802.11 as a suitable communication mean.

• Transmit SMS over 802.11

• Receive SMS on GSM device through 802.11

Scenario

• September 11th 2002New York WTC attack

• September 7th 1999Athens Earthquake

In both situations mobile communications were not available as the networks were overloaded by 400-500%

Scenario

Network

Subscriber

Network

Subscriber

Normal Network Operation

Overloaded Network Operation

Scenario

Network

Subscriber

Network

Subscriber

Normal Network Operation

Overloaded Network Operation

Scenario

Network

Subscriber

Network

Subscriber

Normal Network Operation

Overloaded Network Operation

Scenario

Network

Subscriber

Network

Subscriber

Normal Network Operation

Overloaded Network Operation

Scenario

Network

Subscriber

Network

Subscriber

Normal Network Operation

Overloaded Network Operation

Scenario

Network

Subscriber

Network

Subscriber

Normal Network Operation

Overloaded Network Operation

BOOM !!!

Scenario

Network

Subscriber

Overloaded Network Operation

•Overload

•Congestion

Companies assume that only a fraction of their Subscribers will call simultaneously

•Normal operation•Peak times•Occasionally

GSM •Blocks outgoing calls•Interrupts incoming calls•VERIZON – Mobile Cells - Router

CASES•Wired Network Destroyed•Wireless Network Destroyed

•Partial Failure•Complete Failure

Techniques for avoiding congestionSectorizationStatistics- Modelling – Increase BandwidthCaution AI

Theory GSM

• Basic Model

MSC

BSC

BSC

BSC

MH

BTS

BTS

BTS

BTS

BTSMH

MH

MH

MHPSTN

•Authentication•Localization•Call Handling•SMS Management•Connects to PSTN

Mobile HostCELL

PSTN

DESIGN DESICIONSGSM

•Transceiver•GSM probes only CELL site• Mobile phone cannot communicate direct with other mobile phones•Changing software of the mobile device :

REPROGRAM GSM DEVICE

HARDAWARE CHANGES FOR

DIRECT COMMUNICATION

WITH OTHER MOBILES

CHANGE BASIC TUNING SYSTEM -

MODULATION

CHANGE BTS SOFTWARE IN

ORDER TO COMMUNICATE WITH MOBILES

CHANE GSM SOFTWARE IN MSC

STANDIRIZE NEW PROTOCOL

ALL VENDORS MUST AGREE TO NEW STANDARD

OLD MOBILES MUST BE SUBSTITUTED WITH NEW ONES

DESIGN DESICIONSBLUETOOTH

•Up too 8 users•Connection through piconents will be slow•Range is 100 -200 meters•Rooting ?

Class 3    -    1 mW         (0dBm)         with a 'typical range' of 10mClass 2    -    2.5 mW      (4dBm)         with a 'typical range' of 20m

Class 1    -    100 mW    (20dBm)        with a 'typical range' of 100m Link data rate -  a maximum link baseband data rate of 723.2 kb/

802.11 Wireless Lan

802.11 Wireless Lan

Stations can communicate among each other (Ad hoc Mode) or with stations beyond their direct communication range with the support of an infrastructure (Infrastructure Mode).

•Ad Hoc Capabilities•Support Infrastructure•Privacy•Transparency

‘Infrastructure' mode, a communication method that requires a wireless access point.

(802.11b) may communicate with each other without a wireless access point –'Ad Hoc' mode

802.11 Wireless Lan

Two of the advantages of the standard are the following: It provides privacy of user information The services are compatible with ad hoc and infrastructure service. For current scenario the transfer rate will be used is 1Mbit/second though 802.11 specification allows up to 54Mbits/second. Its frequency bands are 902-928 MHz, 2400-2483.5 MHz and 5725-5850 MHz. A great issue is that a mobile station is able to communicate with any other mobile or wired station transparently, which means that above the MAC layer 802,11 appears like any other 802.x LAN and offers comparable services.

802.11 Wireless Lan•Range•Speed – Bandwidth•Power consumption

Power Consumption

• Atheros AR5004 chipsets also improve power consumption by 60% over 802.11b chipsets. The chipsets enable a multi-phase approach to signal processing that dramatically extends the battery life of mobile devices. The new design controls the power of different sections of the wireless device according to the level of system and network activity.

http://www.atheros.com/pt/index.html

SMS without network support

GSM PHONE

802.11

No network support

· SMS· IMEI· Phone number

SIM

DISPLAY

802.11

GSM PHONE

802.11

Experiment - Phases

GSM PHONE

802.11

GSM PHONE

PDA WITH 802.11

Phase 1 Implementation on 802.11

Phase 2 Bridge GSM Device with 802.11

Current Status

Experimental PhasePhase 1 • Implementation on 802.11

Phase 2 • Bridge GSM Device with 802.11

Phase 3• Testing

Decision •Libraries •Software •Simulation•Equipment

Conclusions

• Bridge GSM -802.11

• Send SMS without network support through 802.11 (ad hoc mode)

• Send FREE SMS through 802.11 to other users

The End


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