The presentation is about a research made by a German student who have found a new way to make 3D hologram using Wi-fi.

1. Holography through walls using
Wi-fi to overcome hostage crisis
[ Computer Graphics ]

2. Holography
Definition:
Holography is a photographic technique which records the light
scattered from the object and then creates a 3D image of the object using
the recorded information.
Holograms can be created by recording light scattered through objects using
Sound waves, X-rays, gamma rays, neutrons and cold atoms but use of Wi-fi
radiation is quite an elusive area.

3. Holography of Wi-fi Radiations
On 5th May 2017, a research paper was published by German
researchers Philipp Holl and Friedemann Reinhard which says that
holography can be also performed by bandwidth that is used for Wi-fi.
That means radiations from Wi-fi routers stores information
regarding 3D images of its surroundings. This information can be used
to create the 3D hologram.
Paper on Holography using Wi-fi .pdf

4. Holography of Wi-fi Radiations
Process:
(1) When the radiations generated by Wi-fi router propagates, the radiation
have data about the object at its wave front. Group of such radiations can
be used to create the 2D image of the object.
(2) Analysing the same wave front at different point of time can be used to
generate the 3D hologram.

5. Holography of Wi-fi Radiations
According to Philipp Holl, The Process can be implemented using
arrays of antennas or drones. Large number of data receiving antennas
make the 3D reconstruction process faster and easier. This way a 3D
hologram of objects within a building can be generated in 20 to 30 seconds.
The video here may help us understand a few points:

6. Applications
The method can be useful for many purposes like ..
(1) Analysing presence and movement of living beings or object for
security enforcement
(2) Creating responsive holograms to understand properties of objects
(3) Understanding the propagation of Wi-fi signals to make its usage
more effective

7. Security Enforcement
Brett Scharringhausen, the technology scout with Central Command
[ The group which oversees US military operations for the Department
of Defence in 20 countries located throughout the Middle East, northern
Africa, and parts of Asia. ] has taken interest in this holography technology.
Mr. Scharringhausen wants to share the technology with US armed
forces to enforce security.

8. Our Idea .. !!
The 3D hologram which is generated after the data processing can
only be seen on the devices having specific software. If we are able to show
the same hologram using glasses then it can be quite useful for armed forces
to deal the situations like hostage crisis, terrorist attacks, etc.
To implement the idea the hologram should be modified according to
viewer’s perspective. Directions, accuracy and processing speed is still a big
challenge.

9. Dependencies
(1) Looking at the current scenario, the idea is not much economical
(2) Adjusting viewer’s perspective is also a hurdle.
(3) Time taken for processing cannot show real time image.