mobile jammer

Mobile Jammer

By- Saurabh Kumar Gupta

(1120739)

Contents:

What is mobile jammer

History

How it works?

What’s inside jammer

Block diagram of jammer

Type of mobile jammer

Mobile jammers

Application

Future scope and Legal issue

conclusion

Bibliography

What is mobile jammer:

Mobile jammer is used to prevent mobile phones from receiving or

transmitting signals with the base stations.

Mobile jammers effectively disable mobile phones within the defined

regulated zones without causing any interference to other

communication means.

Mobile jammers can be used in practically any location, but are used in

places where a phone call would be particularly disruptive like temples,

libraries, hospitals, cinema halls, schools & colleges etc.

Mobile jammers block mobile phone use by sending out radio waves

along the same frequencies that mobile phones use. This causes

enough interference with the communication between mobile phones

and communicating towers to render the phones unusable.

Upon activating mobile jammers, all mobile phones will indicate “NO

NETWORK”. Incoming calls are blocked as if the mobile phone were off.

When the mobile jammers are turned off, all mobile phones will

automatically re-establish communications and provide full service.

How it works:

Disrupting a cell phone is the same as jamming any other type of radio

communication. A cell phone works by communicating with its service

network through a cell tower or base station. Cell towers divide a city

into small areas, or cells. As a cell-phone user drives down the street,

the signal is handed from tower to tower.

A jamming device transmits on the same radio frequencies as the cell

phone, disrupting the communication between the phone and the cell-

phone base station in the tower. It’s a called a denial-of-service attack.

The jammer denies service of the radio spectrum to the cell-phone

users within range of the jamming device

History:

Cell phone jamming devices were originally developed for law enforcement

and the military to interrupt communications by criminals and terrorists.

Some were also designed to foil the use of certain remotely detonated

explosives.

The civilian applications were apparent, so over time many companies

originally contracted to design jammers for government use switched over to

sell these devices to private entities.

Since then, there as been a slow but steady increase in their purchase and

use especially in major metropolitan areas

What’s inside jammer:

Components of a mobile jammer include:

1-Voltage Controlled Oscillator(VCO)

2-Tuning Circuit

3-Noise Source

4-RF Amplification Unit

5-Transmitting Antenna

1-Voltage Controlled Oscillator(VCO):-

It is like a heart of our jammer. VCO’s can be built using op-amps, resistors

and capacitors . VCO produces RF signal which will interact with the blocked

device. Firstly we must select frequencies which will be used in our signal

blocking device.

2-Tuning Circuit:-

can be of two types:

• open-loop

• feedback

a)Open-loop is quite simple and requires just a few op-amps with additional

passive components.

b)It is a saw tooth-wave generator which makes VCO to go from lowest to

highest frequency. The feedback is using PLL to adjust the VCOs frequency

constantly. For this purpose we need to use microcontroller.

c)It is programmed once and then connected to the VCO, thus it is not

adjustable it.

3-Noise generator:-

Produces random electronic output in a specified frequency range to jam the

cellphone network signal (part of the tuning circuit).

4-RF Amplification Unit:-

RF Amplification Unit is what we need when we wish to increase the area

covered by our jammer along with its signal blocking power. The more power

has our signal blocker, the bigger radius it jams. The cost is, as we may

guess, battery working time. More power equals less time for battery to live.

5-Transmitting Antenna:-

a)Transmitting Antenna is a tool which transmits signals produced by your

jammer.

b)The main characteristic of antenna is VSWR (Voltage Standing Wave

Ratio). If your antenna has VSWR of 3 or lower, then this is what you need,

because the return loss of this antenna is minimal.

6-Power Source:-

Power Source makes our creation to become alive. Generally mobile phone

jammers use 5VDC to operate. Thus you may use Lithium-ion battery to

supply our creation.

IF Section

RF Section

Power Supply

BLOCK DIAGRAM OF MOBILE JAMMER

Type of mobile jammer:

There are various types of jamming devices available which are

using different 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

1. Type "A" Device: JAMMERS -

This type of device comes equipped with several independent

oscillators transmitting ’jamming signals’ capable of blocking

frequencies used by paging devices as well as those used by cellular

systems control channels for call establishment

2.Type “B” Device: INTELLIGENT CELLULAR DISABLERS-

Unlike jammers, Type ”B” devices do not transmit an interfering signal

on the control channels. The device, when located in a designated

’quite’ area, functions as a ’detector’. It has a unique identification

number for communicating with the cellular base station.

3. Type “C” Device (Intelligent Beacon Disablers)-

Unlike jammers, Type C devices do not transmit an interfering signal on

the control channels. The device, when located in a designated ’quiet’

area, functions as a ’beacon’ and any compatible terminal is instructed

to disable its ringer or disable its operation, while within the coverage

area of beacon.

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

This jammer behaves like a small, independent and portable base

station, which can directly interact intelligently or unintelligently with

the operation of the local mobile phone. The jammer is predominantly in

receive mode and will intelligently choose to interact and block the cell

Phone directly if it is within close proximity of the jammer.

5. Type E Device (EMI Shield - Passive Jamming)-

This technique is using EMI suppression techniques to make a room into

what is called Faraday cage. Although labor intensive to construct, the

Faraday cage essentially Blocks or greatly attenuates, virtually all

electromagnetic radiation from entering or leaving the cage - or in this

case a target room

Mobile Jammers:

Mobile jamming is the delivery of the radio signals that interrupt

communications by decreasing the radio signals to noise signal ratio.

Mobile phone intentional communications jamming is generally focused on

to radio signals to interrupt control of battle expectations.

Warranty: 1 year

Shipping time:1-2 working days

Cod services: Available in Delhi & NCR only

Battery backup: 2-3 hours

Courier Via: Blue Dart & DTDC Total output power: 0.4Watt

Effective range: Radius Up to 10 Meters.

Whole Weight: 68g.

Work time: 150 minutes.

1-POCKET PHONE JAMMER

IT’S FEATURES

2- WIRELESS SPY CAMERA JAMMER

AA wireless jammer is a widget used to maintain interrupt or disrupt radio

or camera signals. It is generally used to dislocate transmitting and

receiving signals. Generally People whether in any organization or any

personnel business need to have role playing detective using spy camera,

spy audio in the entire area.

Warranty: 1 Year Warranty

Battery backup: 2-3 Hours


Shipping Time: 1-2 working days

COD Services: Available in Delhi & NCR only

Courier via: Blue Dart & DTDC

Total output power: 2.7Watt

Effective range: Radius Up to 20 Meters.

Work time: 90 minutes

Whole Weight: 0.68KG

IT’S FEATURES

When the high power mobile phone jammer is installed as well as on at the

restriction workplace then it obstructs all incoming signals from the

station to the mobile phones and from the mobile phones to the station.

Generally when we are conducting any high profile business meeting

where the communication over mobile phone is totally expelled during the

business meeting duration, the mobile phone jammer is the boon at that

time.





Output Power: 10 Watts

Affected Radius: up to 40 meters

Power Source: Wall plug or car adapter

Antenna Length: 211 mm

Catalog Ref: Cell phone jamming

3-HIGH POWER MOBILE JAMMER

IT’S FEATURES

The mobile signal jammer is a circuit device that is generally used to

blockade the communication of the mobile phone signals within a certain

entire range and any restricted nearby workstations.

A mobile signal jammer is such kinds of device which have different kinds

of frequencies depending on the different types of models by which you

could operate the suitable frequency signals in consider of you have need.





Total Power: 12watt

Power Supply: AC 110-240V / DC 5V

Shielding Radius: Up to 40 meters

Weight: 3 KG

Size: 263(L)*140(W)*50(H)mm

4-MOBILE SIGNAL JAMMER

( HIGH POWER 4G)

IT’S FEATURE

Dual Mode Jammer less complex, high frequency jamming device

effectively blocks mobile phone signal within the radius of 30 meter this

still depends on strength of signal in given area, while sophisticated

jammers can block several types of networks at once dual-mode or tri-

mode phones that automatically switch among different network types to

find an open signal.





Total output power: 10W

Jamming range: Radius up to 30m

Power: AC110V~~240V, DC 12V/5A

Working time: Can work 24-7 continuously

Dimension :( L * W* H): 250*170*70mm

Full Set Weight: 1.27KG

5-DUAL MODE PHONE JAMMER

IT’S FEATURES

Application:

To maintain the complete silence in library and lecture hall.

To avoid fraud in examination hall.

For, providing security in business conference, board of directors

rooms , seminars, etc.

For providing calm and peaceful atmosphere in Hospitals.

Church/Mosques/Cathedral/Temple/Religious establishment

During a hostage situation, police can control when and where a

captor can make a phone call. Police can block phone calls during a

drug raid so suspects can't communicate outside the area.

jammers can be used in areas where radio transmissions are

dangerous, (areas with a potentially explosive atmosphere), such as

chemical storage facilities or grain elevators.

Corporations use jammers to stop corporate espionage by blocking

voice transmissions and photo transmissions from camera phones.

Cell phone jamming devices were originally developed for

law enforcement and the military to interrupt communications

by criminals and terrorists

The bombs that blew up commuter trains in Spain in March

2004, as well as blasts in Bali in October 2002 and Jakarta in

August 2003, all relied on cell phones to trigger explosives.

Future scope:

While the law clearly prohibits using a device to actively disrupt

a cell-phone signal, there are no rules against passive cell-

phone blocking.

Companies are working on devices that control a cell phone but

do not jam the signal.

Since these jammers actively broadcast radio signals, they may or

may not be legal to possess or operate based on the specific laws

of the area one is in.

United States: Cell phone blocking devices are used by federal

officials under certain circumstances.

Germany: illegal, but installation in jails has been proposed.

India: legal, Government, Religious Places, Prisons and

Educational Institutions use jammers.

Pakistan: It’s illegal to operate a jammer without the N.O.C. from

Ministry of Interior and Ministry of Telecom

Legal issues:

Conclusion:

Every device is acts as good aspects as well as bad aspects.

In many place cell phone jammer is useful but at many place it

is a problem.

Jamming is seen as property theft, safety hazard.

But it’s overall performance is very good and helpful in our life.

Good Aspect

Bad Aspect-

Bibliography:

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

2. http://blog.jammer-store.com/2009/11/how-mobile-jammers-

work/

3. Google Search and Image search

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

mobile jammer

Engineering