Wi-Vi technology, developed at MIT, allows the detection of motion and simple gestures through walls using low-power Wi-Fi signals. It consists of a transmitter with two antennas and a single receiver, operating on principles similar to radar and sonar. This emerging technology has various applications, including personal security and firefighting, and holds potential for further development in seeing through solid materials.

1. WIRELESS VISION (WI-VI) technology
K.R.SHYAM
114P1AO438
ELECTRONICS AND COMMUNICATION ENGINEERING
YOGANANDA INSTITUTE OF TECHNOLOGY AND SCIENCES
MOHAN REDDY NAGAR, ELAMANDYAM (V), RENIGUNTA (M), TIRUPATI.

2. CONTENTS
• INTRODUCTION
• HISTORY
• CONSTRUCTION
• BASIC PRINCIPLE
• WORKING
• APPLICATIONS
• FUTURE DEVELOPMENTS
• CONCLUSION

3. INTRODUCTION
 Wi-Fi can also extend our senses, enabling us to see moving objects through walls and behind closed
doors.
 In particular, we can use such signals to identify the number of people in a closed room and their relative
locations.
 We can also identify simple gestures made behind a wall. This is called the Wi-Vi Technology.
 Wi-Fi signals are typically information carriers between a transmitter and a receiver.

4. HISTORY
 MIT researchers have developed a sort of x-ray vision device that can
detect motion behind walls or other large objects.
 Wi-Vi was created by Dina Katabi, a professor in MIT’s.
 Wi-Vi was first introduced in the year 2013.
Dina Katabi

5. WHAT CAN WI-VI DO?
 Detects the number of moving humans in a closed room.
 Determine the relative locations of moving image.
 Enable Communication through wall carrying wireless device.
 Identify simple gestures from behind the wall.

6. WI-VI CONSTRUCTION
Wi-Vi like any other system essentially consists of a Transmitter and a Receiver.
A Wi-Vi system constitutes-
• Two transmitting antennas.
• Single receiver.

7. EXPERIMENTAL SETUP

8. WHY USE WI-FI SIGNALS?
 Wi-Fi signals can easily penetrate through walls.
 Wi-Vi relies on a simple hardware of 2.4 GHz Wi-Fi radios
 Small enough to be portably used.
 Integrated in hand held devices.
 Low power Wi-Fi signals are used.

9. BASIC PRINCIPLE
 Based on the principle of RADAR and SONAR imaging.
 WI-VI is potentially an X-Ray vision created with low power Wi-Fi
signals
 RADAR and SONAR work on the Doppler effect.
 This technology uses reflected Wi-Fi signals to track the movement
of people behind walls.

10. Automatically Detecting the Number of Moving Objects
Detected
Actual
0 1 2 3
EFFICIENCY:
0 100% 0% 0% 0%
1 0% 100% 0% 0%
2 0% 0% 85% 15%
3 0% 0% 10% 90%

11. IDENTIFYING MOTION

12. WORKING
 Wi-Vi uses two transmitting antennas and a single receiver.
 Transmitting signals are low power Wi-Fi signals
 Two antennas transmit almost identical signals, except the second antenna’s signal is the inverse of
the first, resulting in interference.
 Any static objects that the signals hit including the wall create identical reflections.
 As the person moves through the room, his or her distance from receiver changes.

13. GESTURES AS DETECTED BY WI-VI

14. WI-VI OUTPUTS

15. PRACTICAL WI-VI

16. ADVANTAGES OF WI-VI
 Wi-Vi requires only a few MHz of bandwidth and operates in the same range as Wi-Fi. It operates
in ISM band.
 Wi-Vi can perform through-wall imaging without access to any device on the other side of the
wall.
 Wi-Vi employs signals whose wavelengths are 12.5 cm.
 Extend human vision beyond the visible electromagnetic range, allowing us to detect object in the
dark or in smoke.

17. APPLICATIONS
Police avoid ambush Firefighters check for humans
Personal security Gesture interface from behind a wall

18. FUTURE DEVELOPMENTS
 Wi-Vi technology has just been introduced.
 It is an emerging technology with a wide range of
applications.
 In the possible future we would be able to see through
solid materials by using smart phones

19. CONCLUSION
 The possibilities are numerous and can be explored further.
 If this technology can be put into practical use, It can be used in a variety of applications.
 We will proceed toward the cleaner, greener, safer and brighter future.
 Wi-Vi technology can change our world before we realize it.

20. REFERENCES
 http://people.csail.mit.edu/fadel/wivi/design.html
 http://mcdonnellqumba.blogspot.in/2013/06/get-xray-vision-with-wivi-technology.
html
 http://geekshots.in/2013/12/16/wi-vi-wifi-vision-vision-behind-the-walls/
 http://www.redorbit.com/news/technology/1112886700/wivi-uses-wifi-to-see-through-
walls-062813/

21. ANY QUESTIONS?

22. Sri Venkateswara University
Near Sri Padmavati Mahila Visvavidyalayam, Prakasam Nagar Colony, Tirupati, AP 517502