WIRELESS SIGNAL JAMMING

By

Eng. Mahmoud Abdeen Mohammed

Agenda2

1. Introduction2. Jamming Types and Forms3. Components4. GSM Jamming Jamming techniques Comparison between techniques. Use of Jamming 4. Future step .

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- Jamming ( prevent victim to receive data(

- Spying ( receive data & ability to decryption (

- Attack ( transmit fake data && control on victim network(

Wireless Attack Phases

What is Jammer

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is a device that transmit signal on the same frequency at which the wireless system operates, the jamming success when the receiver in the area where the jammer is located are disable to receive data

Beginning

Communication jamming devices were first developed and used by military. Where tactical commanders use RF communications to exercise control of their forces

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Jamming types 7

Obvious jamming - can be heard on the receiving equipment - easy to detect Subtle jamming - Just noise is transmitted - everything seems normal to the operator - use in modern equipment

Components

- Noise Source- Voltage Controlled Oscillator (VCO)- frequency Tuner Circuit - RF Amplification Unit - Transmitting Antenna

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Jamming Forms

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Wifi & Bluetooth Jamming

Satellite Jamming- Libyan Revolution

Radio Jamming- Used in 2nd world war

GSM mobile Jamming

Figure show signal jamming

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About GSM

Global System For MobilesSpectrum range: 890Mhz - 915MHz [uplink] 935Mhz - 960MHz [downlink]Short message service [SMS]

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Jamming techniques• Type "A" Device: JAMMERS

• Type “B” Device: INTELLIGENT CELLULAR DISABLERS

• Type “C” Device: INTELLIGENT BEACON DISABLERS

• Type “D” Device: DIRECT RECEIVE & TRANSMIT JAMMERS

• Type “E” Device: EMI SHIELD - PASSIVE JAMMING

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Type "A" Device: JAMMERS

- several independent oscillators transmitting ‘jamming signals’[from 890 to 960 MHz] capable of blocking frequencies used by paging devices

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Type “B” Device: INTELLIGENT CELLULAR DISABLERS

device works as a detector, and it capable to communicate with the cellular base station, When the device detects the presence of a mobile phone in the "silent" room; a prevention of authorization of call establishment is done by the software at the base station. 

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Type “C” Device (Intelligent Beacon Disablers)

• The device, when located in ’quiet’ area, functions as a ’beacon’ and any compatible terminal is ordered to disable its ringer or disable its operation.• handset must re-enable its normal function as it leaves the coverage area of the beacon.

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Type “D” Device (Direct Receive & Transmit Jammers)

This jammer is similar to type "A" , but jam signal would only stay on as long as the mobile trying to make a link with the base station; otherwise there would be no jamming transmission.

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 Type E Device (EMI Shield - Passive Jamming)

This technique is using EMI suppression techniques to make a room into what is called Faraday cageFaraday cage essentially Blocks or greatly attenuates all electromagnetic radiation from entering or leaving the cage.

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Comparison between techniques

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GSM jammer Use :-

Disabling mobile phones in specific places where the ringing of cell phone would be disruptive as-:

-worship places (Mosque, Church, ... ) -university lecture rooms

-libraries -hospitals

-concert halls -meeting rooms

and any other places where silence is appreciated

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Future Step …..