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Cell Phone Jammer
RONSON CALVIN FERNANDES

Mail To : ronson425@gmail.com

110919053
MIT – MANIPAL
11/18/2013

1
Contents
 Introduction

 Cell Phone Jamming device
 How Cell Phone Jamming Works
 Types Of Jammer Device

 Applications of Cell Phone Jamming
 Legal Issues related to Cell Phone Jamming
 Conclusion

11/18/2013

2
Introduction
 Cell phone jammers are devices that create a temporary "dead zone" to all cell
phone traffic in their immediate proximity.

 A jamming device transmits - same radio frequencies of greater power as the
cell phone, disrupting the communication between the phone and the cellphone base station in the tower.
 It's a called a denial-of-service attack.
11/18/2013

3
Introduction ( Continued . . )
 Disrupting a cell phone is the same as jamming any other type of radio

communication.
 A cell phone works by communicating with the service network through a cell

tower as base station.
 Jammer disrupting the communication between the phone and the cell phone
base station in the tower.
11/18/2013

4
Cell Phone Jamming Device
 Jamming devices overpower the cell phone by transmitting a signal on the
same frequency.
 Power of the signal should be high enough so that the two signals collide and

cancel each other out.
 The phone is tricked into thinking there is no service because it can receive

only one of the frequencies.
11/18/2013

5
Jamming Device ( Continued . . )
 Less complex devices block only one group of frequencies, Some of the high-

end devices block all frequencies at once.
 Low-powered jammers block calls in a range of about
30 feet (9 m).

 Higher - powered units - as large as a football field.
 Law enforcement jammer units - up to 1 mile
(1.6 km) from the device.

11/18/2013

6
Components of Jamming Device
 The simplest just have an on/off switch and a light that indicates it's on.
 Complex devices have switches to activate jamming at different frequencies.

 Main Components :
 Power Supply
 Circuitry
 Antenna
11/18/2013

7
Components ( Continued . . )
Circuitry
The main electronic components of a jammer are:

 Voltage-controlled oscillator

 Tuning circuit
 Noise generator
 RF amplification

11/18/2013

8
How Cell Phone Jammers Work ?
 Cell phone jammers work in a similar way to radio jammers by sending out the

same radio frequencies that cell phones operate on.
 This creates enough interference so that a call cannot connect with a cellphone.
 2 types of jammers. The first type are usually smaller devices that block the
signals coming from cell phone towers to individual cell phones.

11/18/2013

9
How Jammers Work ? (
Continued . . )
 Can block signals within about a 30-foot radius. Cell phones within this range
simply show no signal.
 The second type of cell phone jammer is usually much larger in size and more
powerful.
 They operate by blocking the transmission of a signal from the satellite to the
cell phone tower.
11/18/2013

10
How Jammers Work ? (
Continued . . )

11/18/2013

11
Types of cell phone jammer device
 Cell Phone Jammer

 Portable Cell Phone Jammer
 Remote Control Cell Phone Jammer
 Adjustable Cell Phone Jammer
 School & Prison Phone Jammer
 Explosion - Proof Cell Phone Jammer
 Police & Military Phone Jammer

11/18/2013

12
Applications of Cell Phone
Jamming
 Cell phone jamming devices were originally developed for law enforcement
and the military to interrupt communications by criminals and terrorists.

 During a hostage situation or drug raid police can control when and where a
captor can make a phone call.

 Cell-phone jammers can be used in areas where radio transmissions are
dangerous.
11/18/2013

13
Applications ( Continued . . )
 Corporations use jammers to stop corporate espionage by blocking voice
transmissions and photo transmissions from camera phones.
 Can be used in the areas like Schools or Academic areas , Exam centers ,
Medical facilities , Public libraries.
 Can be used in Govt. offices and High security areas like Prisons , Courts ,
Scientific research labs and Military facilities.
11/18/2013

14
Cell Phone Jamming Legal Issues
 Cell phone jammers are illegal in most countries — except to military, law
enforcement and certain governmental agencies.
 It’s a “Property Theft”.

 It also represents a “Safety Hazard”.

11/18/2013

15
Legal Issues ( Continued . . )
 In India - legal, Government, Religious Places, Prisons and Educational
Institutions use jammers
 India has installed jammers in parliament and some prisons.

 It has been reported that universities in Italy have adopted the technology to
prevent cheating. Students were taking photos of tests with their camera
phones and sending them to classmates.
11/18/2013

16
Conclusion
 We can say every device is acts as good aspects as well as bad aspects.

 Operating or even owning a cell phone jammer is illegal in most municipalities
and specifically so in the United States.
 Jamming is seen as Property Theft, Safety Hazard.

 In many place cell phone jammer is useful but at many place it is a problem .
 But it’s overall performance is very good and helpful in our life.
11/18/2013

17
References
[1] "Zone of silence [cell phone jammer]," Spectrum, IEEE , vol.42, no.5, 18,
May 2005
[2] Sami Azzam, Ahmad Hijazi, Ali Mahmoudy. ”Smart Jammer for mobile phone
systems”
[3] Mobile & Personal Communications Committee of the Radio Advisory Board of

Canada, “Use of jammer and disabler Devices for blocking PCS, Cellular & Related
Services”
[4] www.HowStuffWork.com

11/18/2013

18
11/18/2013

19

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Cell phone jammer ppt

  • 1. Cell Phone Jammer RONSON CALVIN FERNANDES Mail To : ronson425@gmail.com 110919053 MIT – MANIPAL 11/18/2013 1
  • 2. Contents  Introduction  Cell Phone Jamming device  How Cell Phone Jamming Works  Types Of Jammer Device  Applications of Cell Phone Jamming  Legal Issues related to Cell Phone Jamming  Conclusion 11/18/2013 2
  • 3. Introduction  Cell phone jammers are devices that create a temporary "dead zone" to all cell phone traffic in their immediate proximity.  A jamming device transmits - same radio frequencies of greater power as the cell phone, disrupting the communication between the phone and the cellphone base station in the tower.  It's a called a denial-of-service attack. 11/18/2013 3
  • 4. Introduction ( Continued . . )  Disrupting a cell phone is the same as jamming any other type of radio communication.  A cell phone works by communicating with the service network through a cell tower as base station.  Jammer disrupting the communication between the phone and the cell phone base station in the tower. 11/18/2013 4
  • 5. Cell Phone Jamming Device  Jamming devices overpower the cell phone by transmitting a signal on the same frequency.  Power of the signal should be high enough so that the two signals collide and cancel each other out.  The phone is tricked into thinking there is no service because it can receive only one of the frequencies. 11/18/2013 5
  • 6. Jamming Device ( Continued . . )  Less complex devices block only one group of frequencies, Some of the high- end devices block all frequencies at once.  Low-powered jammers block calls in a range of about 30 feet (9 m).  Higher - powered units - as large as a football field.  Law enforcement jammer units - up to 1 mile (1.6 km) from the device. 11/18/2013 6
  • 7. Components of Jamming Device  The simplest just have an on/off switch and a light that indicates it's on.  Complex devices have switches to activate jamming at different frequencies.  Main Components :  Power Supply  Circuitry  Antenna 11/18/2013 7
  • 8. Components ( Continued . . ) Circuitry The main electronic components of a jammer are:  Voltage-controlled oscillator  Tuning circuit  Noise generator  RF amplification 11/18/2013 8
  • 9. How Cell Phone Jammers Work ?  Cell phone jammers work in a similar way to radio jammers by sending out the same radio frequencies that cell phones operate on.  This creates enough interference so that a call cannot connect with a cellphone.  2 types of jammers. The first type are usually smaller devices that block the signals coming from cell phone towers to individual cell phones. 11/18/2013 9
  • 10. How Jammers Work ? ( Continued . . )  Can block signals within about a 30-foot radius. Cell phones within this range simply show no signal.  The second type of cell phone jammer is usually much larger in size and more powerful.  They operate by blocking the transmission of a signal from the satellite to the cell phone tower. 11/18/2013 10
  • 11. How Jammers Work ? ( Continued . . ) 11/18/2013 11
  • 12. Types of cell phone jammer device  Cell Phone Jammer  Portable Cell Phone Jammer  Remote Control Cell Phone Jammer  Adjustable Cell Phone Jammer  School & Prison Phone Jammer  Explosion - Proof Cell Phone Jammer  Police & Military Phone Jammer 11/18/2013 12
  • 13. Applications of Cell Phone Jamming  Cell phone jamming devices were originally developed for law enforcement and the military to interrupt communications by criminals and terrorists.  During a hostage situation or drug raid police can control when and where a captor can make a phone call.  Cell-phone jammers can be used in areas where radio transmissions are dangerous. 11/18/2013 13
  • 14. Applications ( Continued . . )  Corporations use jammers to stop corporate espionage by blocking voice transmissions and photo transmissions from camera phones.  Can be used in the areas like Schools or Academic areas , Exam centers , Medical facilities , Public libraries.  Can be used in Govt. offices and High security areas like Prisons , Courts , Scientific research labs and Military facilities. 11/18/2013 14
  • 15. Cell Phone Jamming Legal Issues  Cell phone jammers are illegal in most countries — except to military, law enforcement and certain governmental agencies.  It’s a “Property Theft”.  It also represents a “Safety Hazard”. 11/18/2013 15
  • 16. Legal Issues ( Continued . . )  In India - legal, Government, Religious Places, Prisons and Educational Institutions use jammers  India has installed jammers in parliament and some prisons.  It has been reported that universities in Italy have adopted the technology to prevent cheating. Students were taking photos of tests with their camera phones and sending them to classmates. 11/18/2013 16
  • 17. Conclusion  We can say every device is acts as good aspects as well as bad aspects.  Operating or even owning a cell phone jammer is illegal in most municipalities and specifically so in the United States.  Jamming is seen as Property Theft, Safety Hazard.  In many place cell phone jammer is useful but at many place it is a problem .  But it’s overall performance is very good and helpful in our life. 11/18/2013 17
  • 18. References [1] "Zone of silence [cell phone jammer]," Spectrum, IEEE , vol.42, no.5, 18, May 2005 [2] Sami Azzam, Ahmad Hijazi, Ali Mahmoudy. ”Smart Jammer for mobile phone systems” [3] Mobile & Personal Communications Committee of the Radio Advisory Board of Canada, “Use of jammer and disabler Devices for blocking PCS, Cellular & Related Services” [4] www.HowStuffWork.com 11/18/2013 18

Editor's Notes

  1. Cell-phone users don't know they're being jammed. The phones just indicate that there's no service or no signal from the network. The jammer simply interrupts the phone's ability to establish a link with the nearest cell-phone tower.
  2. Cell phones are designed to add power if they experience low-level interference, so the jammer must recognize and match the power increase from the phone. The actual range of the jammer depends on its power and the local environment, which may include hills or walls of a building that block the jamming signal
  3. Jamming Devices are very basic devices.Power supply Smaller jamming devices are battery operated. Some look like cell phone and use cell-phone batteries. Stronger devices can be plugged into a standard outlet or wired into a vehicle's electrical system. Antenna Every jamming device has an antenna to send the signal. Some are contained rical cabinet. On stronger devices, antennas are external to provide longer range and may be tuned for individual frequencies.
  4. Voltage-controlled oscillator - Generates the radio signal that will interfere with the cell phone signal Tuning circuit - Controls the frequency at which the jammer broadcasts its signal by sending a particular voltage to the oscillator Noise generator - Produces random electronic output in a specified frequency range to jam the cell-phone network signal (part of the tuning circuit) RF amplification (gain stage) - Boosts the power of the radio frequency output to high enough levels to jam a signal
  5. The frequency blocked is somewhere between 800MHz and 1900MHz. Cell-phone users don't know they're being jammed. The phones just indicate that there's no service or no signal from the network. The jammer simply interrupts the phone's ability to establish a link with the nearest cell-phone tower.
  6. Some powerful models can block cell phone transmissions within a 5 mile radius. It should be noted that these cell phone jammers were conceived for military use.
  7. The bombs that blew upcommuter trains in Spain in March 2004, as well as blasts in Bali in October 2002 and Jakartain August 2003, all relied on cell phones to trigger explosives.The TRJ-89 jammer from Antenna System & Supplies Inc.carries its own electrical generator and can block cellular communications in a 5-mile (8-km)radius.
  8. According to the U.S. the FCC (Federal Communications Commission) When an end-user pays to use that spectrum, jamming the signal is paramount to 'property theft.‘People can't tell the difference between being jammed and simply having poor signal strength.“safety hazard” because jamming blocks all calls in the area,not just the annoying ones. Jamming a signal could block the call of a babysitter franticallytrying to contact a parent or a someone trying to call for an ambulance.
  9. Jamming is seen as property theft, because a private company has purchased the rights to the radio spectrum, and jamming the spectrum is akin to stealing the property the company has purchased. a safety hazard because jamming blocks all calls in the area, not just the annoying ones. Jamming a signal could block the call of a babysitter frantically trying to contact a parent or a someone trying to call for an ambulance.