Visible Light Communication

You can use light to send data across the room. This type of communication is called Visible Light Communication. LEDs are used in this type of communication. Advantages:

• LEDs are currently penetrating many areas of our everyday life. They are likely to replace high energy consuming light bulbs in private and business homes and even in street lamps. Moreover, they can be used in headlights of planes and trains, front and back lights in cars and trains, and for object illumination in museums, etc.
  
  
• Bandwidth is not limited. So ultra high data rates.
  
  
  
  
• Existing local powerline infrastructure can potentially be utilised.
  
  
• Transmitters and receivers devices are cheap, and there is no need for expensive RF units.
  
  
• As lightwaves do not penetrated through objects or walls. It is very difficult for an intruder to pick up the signal from outside the room.
  
  
• Visible light radiations are undoubtedly free of any health concerns Therefore, these systems will receive acceptance for use in hospitals, private homes, etc.
  
  
• Furthermore, no interference with RF based systems exist, so that the use in airplanes is uncritical.
  
  
• No harmful effects like cellular tower.

The basic block diagram is shown below.

A model for this is shown below.



Visible Light Communication uses the frequencies between 400THz to 800 THz. Different types of modulation techniques can be used. It has both partial and full solution of limited bandwidth.

Applications:

• Smart Home Network.
  
  Enabling smart domestic or industrial lighting, home wireless communication including media streaming and internet access.
  
  
• Hospitals and Helthcare.
  
  Enable mobility and data communication in hospitals. No harmful effects.
  
  
• Defense and Military applications.
  
  High data rate wireless communications within military vehicles and aircraft.
  
  
• Under water communications.
  
  It can communicate between divers and remote vehicles.
  
  
• Hazardous Environment.
  
  Enable data communications in environments where RF is potentially dangerous. Such as oil and gas, petrochemicals and mining.
  
  
• Wi-Fi spectrum release.
  
  Providing additional bandwidth in environments where licensed or unlicensed Communication bands are conjusted.
  
  
• Commercial Aviation.
  
  Enables wireless data communications such as in-flight entertainment and personal communication.
  
  
• Security.
  
  Provides the use of wireless networks where wifi presents security risc.