LiFi (optical wireless transmission, light fidelity) enables mobile communication with light. LiFi is used as a complement to radio, where higher user density requires more capacity. Moreover, LiFi fulfills special safety and electromagnetic compatibility requirements. Nowadays, a LiFi cell has 1-10 m diameter and delivers data rates from 100 Mbit/s to 1 Gbit/s. LiFi is based on commercially available high-performance LEDs, which are also used for lighting, and large-area photodiodes. Technology and costs are similar to those in radio: orthogonal frequency division multiplexing (OFDM) and adaptive transmission are used as well as multiple-input multiple-output (MIMO), relay function and handover between adjecent access points.
The Fraunhofer HHI has developed LiFi from its basics, is contributing to standardization and supports its transfer into applications. Pilot projects are currently taking place with end users in real operating environments.
Currently applications of LiFi are investigated in the commercial sector (business-to-business, B2B) but can also be increasingly address the public and private environment (business-to-customer, B2C).
Further fields of application are networking street lights (smart city), underwater, in medical facilities and in airplanes.