The document discusses different types of cell phone jammers, including their principles of operation, design parameters, functional units, and jamming techniques. It describes how jammers work by transmitting radio frequencies to interfere with cell phone signals and disrupt communication between phones and towers. The document outlines the advantages of jammers for situations like exams or sensitive meetings, but also notes the disadvantages like inconvenience and inability to make emergency calls. It concludes by discussing potential future improvements and both useful and problematic aspects of cell phone jamming technology.

1. Komal Ambedika
Presented By...

2.  Introduction
 Principle of Operation
 Design Parameters
 Functional Units
 Jamming Techniques
 Advantages
 Disadvantages
 Future scope of improvements
 Conclusion

3.  Cell Phone Jammer is a device which creates a
temporary “Dead Zone” to all cell phone’s traffic in
its immediate proximity.
 Practically it can be used at any location but used
mostly in places where silence is expected.
 Disrupting a cell phone is same as jamming any
other type of radio communication.
 Originally developed for law enforcement and the
military to interrupt communications by criminals
and terrorists.

4.  The Jamming Device transmits
same radio frequencies with
greater power as the cell phone.
 It causes enough interference
with the communication
between cell phone and base
stations in the tower .
 Thus it renders the cell phone
unusable . It is called ‘denial-
of-service attack’.

6.  The frequency bands:-
900MHz or 1800MHz
 Distance to be jammed (D) :-
output power of the jammer depends on the area that we need to
jam.
 Free space loss {F}= path loss (dB):-
32.44 + 20 log d(km) + 20log f(MHz)
 Jamming to Signal ratio(J/S):-
Usually, a successful jamming attack requires that the jammer
power is roughly equal to or greater than signal power at the receiver

7. The main electronic components of a jammer are:
 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 by a particular voltage to the
oscillator.
 Noise generator:– Produces random electronic output in a
specified frequency range to jam the telephone network signal
(part of tuning circuit) .
 RF amplification (gain stage) :– Boosts the power of radio
frequency output to high levels for jamming the signal.

8. CONTINUED …
 Antenna :-
 Every jamming device has an antenna to send the signal.
 On stronger devices, antennas are external to provide
longer range and may be tuned for individual
frequencies.
 Power supply :-
 Smaller jamming devices are battery operated.
 Stronger devices can be plugged into a standard outlet or
wired into a vehicle's electrical system.

9. Micro
Controller VCO
Noise
M
Power
Supply
Integrator
Band pass
filter
Amplifier
RF
antenna

10. There are various types of
jamming devices available which
are using different jamming
techniques.
 Type "A" device
 Type "B" device
 Type "C" device
 Type "D" device
 Type "E" device
Type "A" device
 Type "A" devices are simple
jammer.
 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.

11. Type "B" device
 Type "B" devices are also
known as 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.
Type "C" device
 Type "C" devices are also known
as 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 with in the
coverage area of beacon.

12. Type "D" device
 Type "D" devices are
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.
Type "E" device
 Type "E" devices are used
for EMI Shield - Passive
Jamming.
 This technique is using
EMI suppression
techniques to make a
room into what is called
faraday cage.

13.  Police can block phone calls during a drug raid so
suspects can't communicate outside the area.
 Restricts explosion of cell phone triggered bombs .
 Provides security in business conference, board of
director’s rooms, seminars, etc.
 Avoids fraud in examination hall.
 Provides calm and peaceful atmosphere in Hospitals
, churches , temples etc.

14.  Cost oriented.
 Requires special hardware.
 People feel inconvenience.
 V.I.P.’s may loose some important calls.
 As cell phone jammer blocks all the signals within its
working range, there may be grave consequences in an
emergency.

15.  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.

16.  Every device has good as well as bad aspects.
 In many situations cell phone jammer is useful but at many
places it creates problems.
 Cell phone jammers are very useful to the society for
protecting from anti-social elements.
 It’s overall performance is very good and helpful in our lives.

17.  "Zone of silence [cell phone jammer]," spectrum, IEEE , vol.42,
no.5,
18, may 2005
 www.Howstuffworks.com
 Wikipedia .Org /wiki/mobilephonejammer
 Http://whatisacellphonejammer.com
 Http://blog.Jammer-store.Com/2009/11/how-mobile-
jammers-work