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SEMINAR PRESENTATION

Presented By:-

SWATI JAIN

ECE-B

0816431410

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M.J.M=Mobile(which are moving)

J=Jammer(which are controllable)

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Contents

What is it? Introduction Usefulness of jammers Can it be destructive? Working Development over time Jamming techniques

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Continued…

Applications Advantages and disadvantages Conclusion Sources

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What is it?

Cell phone jamming is the use of an electronic device to prevent the transferring of data through a wireless phone.

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INTRODUCTION

JAMMING is the act of intentionally directing electromagnetic energy at a communication system to disrupt or prevent signal transmission.

The GSM Jammer is a device that transmit signal on the same frequency at which the GSM system operates, the jamming success when the mobile phones in the area where the jammer is located couldn’t make or receive call phones.

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Is Jamming useful?

Jammers can be used practically anywhere. Jammers are used primarily where silence is

necessary or data transfer might be destructive.

Jammers are simple to build and use.

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Why might cell phone use be destructive?

As wireless phones rapidly overtook society in the 21st century, many problems arose with the quick, easy option to transfer data either by voice or files through them such as : Espionage, Exposure of images, Recording conversation or video remotely, Cheating

(Academically), etc.

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How do they work?

Jammers simply overflow the frequency used by wireless phones with radio waves

Enough interference caused by these waves will prevent communication between a wireless phone and a base tower

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Some Jammers are small, hand-held sized devices while others can be very large

Smaller Jammers interfere mostly with the wireless phones themselves while devices with larger radii may interfere with the towers directly

Size of jammers.

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Some Quick Numbers…

Wireless phone network ranges generally from 800-1900Mhz.

Small Jammers block all communication in this range for a 30 Ft. radius.

Commercial size Jammers can block all communication for 5 miles.

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Originally much of the technology associated with jamming was developed for military purposes

A huge part of security in the military is data security; Jamming communications signals locally can prevent the loss of data.

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Law Enforcement and Military both use Jammers for preventing signals from certain kinds of remote explosive detonation devices

Some Law Enforcement agencies use Jammers to prevent criminals from communicating

Continued…

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Development Over Time Jammers originally worked on

analog signals

Eventually Jamming was necessary on digital networks

Newer Jammers will block AMPS, CDMA, GSM etc networks.

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Can I have one?

Of course not (legally)! Jammers are highly illegal to civilians in the US

Worldwide they are used in Libraries, Banks, Prisons, Hospitals, Churches, Movie theaters, and other places where locals or govt. have deemed wireless phone use more of a problem.

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JAMMING Techniques.

Type “A”: JAMMERS Type ”B”: Intelligent Cellular Disablers Type “C”: Intelligent Beacon Disablers Type ”D”: Smart JAMMERS Type ”E”: Faraday Cage ( EMI Suppression

Techniques)

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1. “JAMMERS”

This device comes equipped with several independent oscillators transmitting ‘jamming signals’ capable of blocking frequencies used by communicating devices.

But the drawback is that these have poor frequency selectivity and so interfere with a larger spectrum.

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2. “INTELLIGENT CELLULAR DISABLERS”

These function as a DETECTOR. It has a unique identification number for communicating with the base station.

It filters i.e. prevents the authorization of call establishment at the base station.

Messages can be routed to user’s voice mail-box if the users have subscribed to it.

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3.“INTELLIGENT BEACON DISABLERS”.

It functions as a ‘beacon’ and any compatible terminal is instructed to disable its ringer or operation while with in the coverage area of the beacon.

This technology does not require any separate receiver for the beacon system.

The emergent users are informed of a ‘bypass terminal key sequence’.

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4. “DIRECT RECEIVE AND TRANSMIT JAMMERS”

This jammer behaves like a small, independent and portable base station which can directly interact intelligently with the operation of the local mobile phone.

The jammer is predominantly in receiving mode and will block the cell phone directly if it is in close proximity of the jammer.

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5. “EMI SHIELD- PASSIVE JAMMING”

It uses EMI suppression techniques to make a room into what is called a Faraday cage which essentially blocks or attenuates all electromagnetic radiation from entering or leaving the cage.

This passive configuration is currently legal in CANADA for any commercial or residential location.

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Design and Implementation GSM Mobile JAMMER

Power Supply5 V

IF Section

RFSection

Block diagram of the mobile Jammer

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APPLICATION

1. Religious places like temple

2. In Hospitals.

3. During a hostage situation.

4. To stop corporate espionage.

5. Law Enforcement and military security.

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ADVANTAGES

1.Easy to operate

2.Peace and quiet equipment

3.Block any cell phone signal

4.They prevent many lives

5.Prevent people from being destructive by the phone

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DIS-ADVANTAGES

Loss of information

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Conclusion.

Thus through this presentation we intent to prevent the usage of mobile phones in places inside its coverage without interfering the communication channels outside its range. Thus reliable and cheap method of blocking communication in restricted areas. The jammers include intelligent jammers which directly communicates with the GSM provider so that smart phones can be handled as well.

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Sources

http://electronics.howstuffworks.com/cell-phone-jammer.htm

http://wireless.fcc.gov/services/index.htm?job=operations_2&id=cellular

http://en.wikipedia.org/wiki/Mobile_phone_jammer

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ThanksThanks for patience full listing.

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Questions?