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CELL PHONE JAMMER

Presented By:P.Likhitha

Under the esteemed guidance ofMr.G.Guru Prasad, M.Tech.,Assistant ProfessorDepartment of ECE

SREE VIDYANIKETHAN ENGINEERING COLLEGE (AUTONOMOUS)

Sri Sainathnagar, A.Rangampet, Tirupathi-517102

A mini project presentation on

2 CONTENTS: Objective Introduction How Cell Phone Jammer works? Jamming Techniques Block Diagram Circuit Diagram Working Specifications Advantages & Disadvantages Applications Conclusion References.

OBJECTIVE:

The objective of this project is to prevent the cellular phone from receiving and transmitting the mobile signals to the base station, which is now a necessity for accomplishing a more cultured society because there is a growing demand for silence at hospitals, libraries, temples and meeting room.

4 CELL PHONE JAMMER

JAMMER

NONO

NETWORK

5 INTRODUCTION:

An adversary is empowered to launch a severe DOS attack by blocking the wireless medium is through Jamming.

Cell Phone Jammer: A Cell phone jammer is a device used to prevent cellular phones from

receiving signals from base stations. It is a device that transmit signal on the same frequency at which the

GSM system operates, the jamming is success when the mobile phones are disabled in the area where the jammer is located.

6 How Cell Phone Jammer works?

A jamming device transmits - same radio frequencies of greater power as the cell phone, disrupting the communication between the phone and the base station. It's a called a denial-of-service attack.

7 This causes interference with communication of cell phones and towers to render the phones unusable. On most phones, the network would be out of range.

So Jammers work by either disrupting phone to tower frequency or tower to phone frequencies.

8 JAMMER 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

9 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.

10 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.

 

11 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.

12   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.

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

This technique is using EMI suppression techniques to make a room .Although labour intensive to construct, this shield essentially Blocks or greatly attenuates, virtually all electromagnetic radiation from entering or leaving the cage - or in this case a target room.

 

14 Block Diagram:

RF SECTION: In this section there will be a RF amplifier which amplifies the signal from the

tuned circuit.IF SECTION: It includes the tuned circuit which generates noise for the circuit.

If section Rf section Jamming signals

Power supply

15 POWER SUPPLY:

16CIRCUIT DIAGRAM:

Q1BF494

C24.7pF

C34.7pF

L122nH C1

1.42pFR239K

C4102PF

C7103pF

C5

1.0u

3V

C6

2.2pF

ANTENNA (GSM 900)

R1100K

17COMPONENTS:Component Number

Value Usage

R1 100K ohm Emitter Loading

R2 39K ohm Base Biasing

C1 15pf Frequency Generating

C2 4.7pf Feedback

C3 4.7pf Feedback

C4 102pf Noise Reducing

C5 1uf Coupling

C6 2.2pf Coupling

C7 103pf Decoupling

Q1 BF 494 Amplification

L1 22nH Frequency Generating

Antenna GSM 900 Radiates radio frequencies

18 WORKING: Here in this circuit ,when the antenna receives a signal ,if the

frequency of the input signal matches with the tuned circuit frequency then transistor will be on active region and the input signal has grounded.

Whenever the frequency of the signal received doesn’t match with the tuned circuit then it will not be blocked and it doesn’t disrupt the communication between sender and receiver.

19 SPECIFICATIONS:

S.NO Features Values1. Frequency Band 900MHz

(Up Link:890-915MHz, Down Link:935-960MHz)

2. Diameter to be Jammed 10 Meters3. Free space loss {F}= Path Loss

(dB)= 32.44 + 20 log D(km) + 20log f(MHz)

51dB

20 ADVANTAGES:

Portable, Reliable Provide security For Peace By using cell phone jammers in the vehicles, we can overcome

accidents problem, which will be helpful to people.

21 DISADVANTAGES:

Jammers can be used by criminals who break into houses. People feel inconvenience People may lose some important calls.

22 APPLICATIONS: To maintain the complete silence in library and lecture hall To avoid fraud in examination hall To avoid disturbance in class room For providing security in business conference, board of directors

rooms, seminars, etc., For providing calm and peaceful atmosphere in Hospitals

Church/Mosques/Cathedral/Temples.

23 CONCLUSION: Every technology has good aspect as well as bad aspect the

important thing is, how we are using it. Cell phone jammers are very useful to the society from the anti-

social elements. we can restrict the communication network between the anti-social elements by using the Mobile jammers. Cell phone jammers prevent the students from carrying cell phones to the colleges.

24 REFERENCES: Peter Briggs, Rajesh Chundury , Jonathan Olsson, “Carrier Ethernet

for Mobile Backhaul” IEEE Communications Magazine, October 2010

Schiller, " Mobile Communication ",Pearson Education,1 Edition,7th reprint-2011

Ahmed Jisrawi, "GSM 900 Mobile Jammer", undergrad project, JUST, 2010

John Scourias, Overview of the Global System for Mobile Communications, University of Waterloo.

https://en.wikipedia.org/wiki/Mobile_phone_jammer http://electronics.howstuffworks.com/cell-phone-jammer1

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QUERIES?