TECH

With the help of a single blue LED, the French dispersed the LiFi network at record speed

Researchers at the CEA-Leti Institute have set a bandwidth record for LiFi communications using only a blue micrometer-sized GaN LED. Thus, the previous record of bandwidth at the 5.1 Gbit / s level was broken and a new one was established - around 7.7 Gbit / s.
The LiFi of communication (fidelity to light) promises to become a “safe WiFi” in rooms and vehicles. The data on LiFi networks are transmitted in the visible light band, which eliminates or makes it extremely difficult to intercept information outside the facilities where this network is implanted. LiFi will also help to deploy high-speed wireless networks, where electromagnetic radiation can harm sophisticated electronic equipment - in hospitals, at the workplace or on board an aircraft.
The singularity of the experiment at CEA-Leti lies in the fact that, for the first time, high-speed communication was performed using a single blue LED of gallium nitride with a size of 10 μm. This promises high integration of LiFi transceivers and decent energy efficiency, although a similar array of LEDs is needed to transmit data over medium and long distances.



This technology has enormous potential for mass market applications ”, says Benoit Miscopein, a researcher at CEA-Leti. Systems with multiple LEDs can replace Wi-Fi, but widespread adoption will require a standardization process to allow interoperability between systems from different manufacturers. To encourage the industry to implement this standard, the LiFi Alliance was created in 2019. ”
The bandwidth of a single LED with a size of 10 μm is 1.8 GHz. To save this range for each microLED in an array of thousands of micro-LEDs, hybrid solutions will be required, namely, matrix integration light emitting with control drivers, where each pixel will be controlled by logic with minimal delays. Drivers cannot be placed away from the LiFi light-emitting array, otherwise the transmission speed will decrease markedly. But this hybrid system will provide multiple secure access to the “light” network, but there is still a lot to be done on this path.

AVnews