How the li-fi technology came into existence.How it works and what are the advantages and disadvantages of li-fi technology. For new topics visit my blog http://tulasikrishnaravi.blogspot.in/

2. wi-fi
• WiFi, is a local area wireless technology that
allows an electronic device to exchange data
or connect to the internet using radio waves.

3. Present challenge
• Radio Spectrum is congested but the demand
for wireless data double each year .Every
thing, it seems want to use wireless data but
the capacity is drying up.
• So what can carry this excess demand in the
future .

4. Who can replace radio waves
for wireless communication

6. What is li-fi?
LI-FI is transmission of data through illumination ,sending data through
a LED light bulb that varies in intensity faster than human eye can
follow.

7. History
• The technology truly
began during the 1990's
in countries like Germany,
Korea, and Japan where
they discovered LED's
could be retrofitted to
send information. Harald
Haas continues to wow
the world with the
potential to use light for
communication

8. How it works ?
• operational procedure is very simple, if the led is on, you
transmit a digital 1, if its off you transmit a 0. The LEDs can be
switched on and off very quickly, which gives nice
opportunities for transmitting data. Hence all that us required
is some LEDS and a controller that code data into those LEDs.

12. Advantages
• Lighting points Used as Hotspots
• Can be used in hospitals and even underwater

13. Disadvantages
• Li-Fi doesn’t work in the dark or outdoors.
• Li-Fi has a big drawback compared to Wi-Fi,
unlike wi-fi we cannot move to other rooms
unless there are wired bulbs too.