10 Gbps Li-Fi system shows wireless data transfer in a new light

Li-Fi technology

What is Li-Fi technology?

Li-Fi technology is a ground-breaking light-based communication technology, which makes use of light waves instead of radio technology to deliver data

Li-Fi can compensate as the radio spectrum becomes overloaded

Using the visible light spectrum, Li-Fi technology can transmit data and unlock capacity which is 10,000 times greater than that available within the radio spectrum.

The visible light spectrum is plentiful, free and unlicensed, mitigating the radio frequency spectrum crunch effect.

The future internet

Li-Fi technology will in future enable faster, more reliable internet connections, even when the demand for data usage has outgrown the available supply from existing technologies such as 4G, LTE and Wi-Fi. It will not replace these technologies, but will work seamlessly alongside them.

Using light to deliver wireless internet will also allow connectivity in environments that do not currently readily support Wi-Fi, such as aircraft cabins, hospitals and hazardous environments.

Light is already used for data transmission in fibre-optic cables and for point to point links, but Li-Fi is a special and novel combination of technologies that allow it to be universally adopted for mobile ultra high speed internet communications.

A dual use for LED lighting

The wide use of solid state lighting offers an opportunity for efficient dual use lighting and communication systems.

Innovation in LED and photon receiver technology has ensured the availability of suitable light transmitters and detectors, while advances in the modulation of communication signals for these types of components has been advanced through signal processing techniques, such as multiple-input-multiple-output (MIMO), to become as sophisticated as those used in mobile telecommunications.

An integrated communication solution

Li-Fi technology is being developed into a ubiquitous systems technology, consisting of application specific combinations of light transmitters, light receivers including solar cells, efficient computational algorithms and networking capabilities that can be deployed in a wide range of communication scenarios and in a variety of device platforms.

More about Li-Fi Technology

Light might be the preferred option for transmitting data over long distances via cables, but when it comes to short range wireless, radio waves rule in the form of Wi-Fi and Bluetooth. Now Mexican company Sisoft, working with researchers from the Autonomous Technological Institute of Mexico (ITAM), has developed a wireless technology that transmits data in visible light emitted from LED lamps, while lighting the room at the same time.

Called Li-Fi, which is short for light fidelity, the technology is what is known as Visible Light Communication (VLC). Unlike infrared-based systems, VLC involves transmitting data using light visible to the human eye. In this case it is transmitted as intermittent, imperceptible flickers of light emitted by LEDs.

The team started out with audio, cabling up a protoboard table to a smartphone via its 3.5 mm audio jack. The protoboard table converted the audio signal into an optical signal that is transmitted by a special emitter across the spectrum of light generated by an LED lamp. At the receiving end, a receptor located in a speaker captured the signal and converted it back into an audio signal that was played by the speaker.

For wireless internet transmission, the principle is the same but makes use of a receptor device designed to be placed above a router. The router incorporates an LED lamp to transmit data so anyone falling within the halo of light emitted by the LED will be in range. However, only those with a receptor/transmitter device will be able to send and receive the signal.

The Sisoft team says it has used the technology to transmit audio, video and internet at rates of up to 10 gigabits per second. This is an improvement over similar Li-Fi systems developed at Siemens and Pennsylvania State University that achieved transfer rates of 500 Mbps and 1.6 Gbps, respectively.

In addition to its impressive transfer rate, Sisoft also highlights other benefits of the technology. Since the data is transferred via light, there is no way to hack it, making it safer, (although no mention is made of how easy it would be to take a peek at the data someone else is receiving). Additionally, it could be used in areas such as hospitals where radiation equipment can block or disrupt wireless signals. And of course, it provides illumination at the same time.

Source: Sisoft de Mexico