SEMINAR ON

1. SEMINAR ON RADAR JAMMING PRESENTED BY K PAVAN KUMAR SATEESH KUMAR P REG NO.:0501222118 REG NO.:0501222049

2. INTRODUCTION • Radar jamming is the intentional emission of radio frequency signals to interfere with the operation of a radar by saturating its receiver with noise or false information.

3. RADIO TRANSMITTER • A radio transmitter is a device that oscillates an electrical current so the voltage goes up and down at a certain frequency. This electricity generates electromagnetic energy and this energy travels through the air as an electromagnetic wave. A transmitter also has an amplifier that increases the intensity of the electromagnetic energy and an antenna that broadcasts it into the air.

4. EMISSION OF RADIO WAVES

5. Contd.. • A radio receiver is just the reverse of the transmitter: It picks up electromagnetic waves with an antenna and converts them back into an electrical current. • Radar is the use of radio waves to detect and monitor various objects. The simplest function of radar is to tell you how far away an object is by emitting radio waves and listen for echo.

6. RADAR

7. PRINCIPLE OF RADAR OPERATION • Radar is a system that uses electromagnetic waves to identify the range, altitude, direction or speed of both moving and fixed objects such as aircraft, ships, motor vehicles and weather information.

8. JAMMING PRINCIPLE Jamming can be achieved by two principles : • Either by reflect or re-reflect radar energy back to the radar to produce false target returns on the operator's scope. • Radiate interfering signals toward an enemy's radar, blocking the receiver with highly concentrated energy signals.

9. JAMMING TECHNIQUE According to the principle of operation there are 2 types of jamming techniques : • Mechanical jamming • Electronic jamming

10. MECHANICAL JAMMING • Mechanical jamming is caused by devices which reflect or re-reflect radar energy back to the radar to produce false target returns on the operator's scope.

11. MECHANICAL JAMMING DEVICES Mechanical jamming devices mostly use the following components • Chaff • Corner reflectors • Decoys

12. CHAFF • Chaff is made of different length metallic strips, which reflect different frequencies, so as to create a large area of false returns in which a real contact would be difficult to detect

13. METALPLATES NEAR THE TOP CONFIGURED AT RIGHT ANGLES TO REFLECT RADAR SIGNAL

14. CORNER REFLECTORS • Corner reflectors have the same effect as chaff but are physically very different. • Corner reflectors are multiple-sided objects that re-radiate radar energy.

15. FIG. OF CORNER REFLECTOR

16. DECOYS • Decoys are maneuverable flying objects that are intended to deceive a radar operator into believing that they are actually aircraft.

17. FIG. OF DECOY

18. ELECTRONIC JAMMING • Electronic jamming is a form of Electronic Attack where jammers radiate interfering signals toward an enemy's radar, blocking the receiver with highly concentrated energy signals. • The two main technique styles are noise techniques and repeater techniques.

19. NOISE JAMMING The three types of noise jamming • Spot jamming. • Sweep jamming. • Barrage jamming. • Base jamming.

20. SPOT JAMMING • Spot jamming occurs when a jammer focuses all of its power on a single frequency. A frequency agile radar would hardly be affected because the jammer can only jam one frequency. (Terrorist Trap™ VIP 16 Jamming System)

21. SWEEP JAMMING • Sweep jamming is when a jammer's full power is shifted from one frequency to another. • While this has the advantage of being able to jam multiple frequencies in quick succession, it does not affect them all at the same time, and thus limits the effectiveness of this type of jamming. • Although, depending on the error checking in the device(s) this can render a wide range of devices effectively useless.

22. BARRAGE JAMMING • Barrage jamming is the jamming of multiple frequencies at once by a single jammer. • The advantage is that multiple frequencies can be jammed simultaneously; however, the jamming effect can be limited because this requires the jammer to spread its full power between these frequencies.

23. DEVICE FOR BARRAGE JAMMING • This device is designed for • Making spot, spot-barrage and barrage jamming. • Detection of the executive device receiver parameters

24. BASE JAMMING • Base jamming is a new type of Barrage Jamming where one radar is jammed effectively at its source at all frequencies. However, all other radars continue working normally

25. DRFM JAMMING • Digital radio frequency memory or DRFM jamming or Repeater jamming is a repeater technique that manipulates received radar energy and retransmits it to change the return the radar sees. This technique can change the range the radar detects by changing the delay in transmission of pulses.

26. COUNTERMEASURES • Modern jammers can track a predictable frequency change, so the more random the frequency change, the more likely it is to counter the jammer. • Cloaking the outgoing signal with random noise makes it more difficult for a jammer to figure out the frequency that radar is operating on.

27. APPLICATIONS • Military use. • Civilian world use.

28. CONCLUSION • Jammers radiate interfering signals toward an enemy's radar, blocking the receiver with highly concentrated energy signals. • How different jamming techniques create false target for self defence . • Radar jamming is mainly used in Military bases, Air force and Armed forces.

29. THANK YOU