What is Li-Fi?

Li-Fi is wireless communication technology which utilises light to transmit data and position between devices.

The technology is like Wi-Fi and the key technical difference is Wi-Fi uses radio waves to transmit data and Li-Fi uses light.

This sounds like sorcery, but the technology is nearly 20 years old, in fact the term Li-Fi was coined in 2009.

Using light to transmit data allows Li-Fi to offer several advantages over Wi-Fi

  1. A wider bandwidth meaning more data can be carried on the same signal.
  2. The ability to safely function in areas otherwise susceptible to electromagnetic interference (hospitals etc)
  3. And offering higher transmission speeds

Unlike 5G, there has been no inference about Li-Fi and its effects (or not) on virus transmission or adverse health implications.

How does Li-Fi work?

Li-Fi works by switching the supplied electrical current to the LEDs on and off at a very high speeds, too quick to be noticed by the human eye, thus, it does not present any flickering.

Although Li-Fi LEDs would have to be kept on transmitting data. Lights can be dimmed to below human visibility while still emitting enough light to carry data. 

Li-Fi has the advantage of being useful in electromagnetic sensitive areas such as in aircraft cabins, hospitals and nuclear power plants without causing electromagnetic interference

LiFi compared to 5G and WiFi

4G tops out at a theoretical 100 megabits per second (Mbps), 5G tops out at 10 gigabits per second (Gbps).  That means 5G is a hundred times faster than the current 4G technology—at its theoretical maximum speed. 

LiFi in comparison has reached data transmission rates over 200 Gbps which makes it “faster” than 4G, 5G.

Most of the broadband speeds in the UK are less than 10 Mbps. Wi-Fi is close to full capacity and is experiencing a “spectrum crisis”, with bandwidths congested and often overlapping.

Li-Fi has almost no limitations on capacity as the visible light spectrum is 10,000 times larger than the entire radio frequency spectrum.

Li-Fi is expected to be ten times cheaper than Wi-Fi, so what is the catch?

Downsides of Li-Fi

 In a nutshell, short range, low reliability and high installation costs.

Li-Fi is not ideally adjusted for mobile communications. Li-Fi is currently more expensive than Wi-Fi solutions and requires the modification of an existing Wi-Fi network to implement.  Li-Fi transmitters must be installed on the network as well as on user devices to facilitate communications.

Li-Fi is also limited in its transmission area. The receiver on the user’s device must be directly in the line of sight of the network transmitter or signal as; light reflected off walls can achieve 70 Mbps. The light signals that Li-Fi produces cannot pass through walls and obstacles. Because of this, there must be a Li-Fi transmitter in every room where devices will be used.

Because of this “hand offs” between access points and devices can become an issue if the user wishes to roam within the building or join a public network with their device.

However, if you are not in a price sensitive scenario and are looking for a more solution, as Li-Fi cannot be hacked through walls like Wi-Fi, then Li-FI may be a good option.

Conclusion

The current development of Li-Fi products has several limitations, but with further development this could be a revolutionary new product that completely replaces traditional Wi-Fi.  With modifications on the network, Li-Fi could be a hybrid and complimentary solution to existing networks to increase security.

Li-FI could become a key complementary technology, handling data in areas where its limitations aren’t a problem and lessening the load on radio frequency spectrum in the process.

The potential for Li-Fi is obvious and many companies have trials in place. For anyone who can successfully integrate the technology to multiple use cases the benefits are obvious with a market projected at £65 million over the next five years.

For now, hybrid 4/5G and Wi-Fi solutions are here to stay.