Li-Fi (light-based wireless networking)

Also known as LiFi, Light fidelity, Visible light communication (VLC), IEEE 802.11bb light communications

Li-Fi sends data by rapidly switching the light from LEDs or lasers, and the IEEE 802.11bb light-communications standard was approved in 2023. Single-emitter laboratory links have exceeded 9 Gb/s over short distances, but the link needs an unobstructed path, and the uplink from small devices remains a design challenge.

Pilot and early commercialDemonstratedReviewed 22 Oct 2026
AI illustration · Illustrative scene, not a photograph of the specific device or experiment.

In plain language

Li-Fi sends data by changing the brightness of a light very quickly. An LED is switched on and off faster than the eye can notice, and a light sensor, usually a photodiode, reads the pattern and turns it back into digital data. Because the light is visible, the same lamp that lights a room can also carry a signal.

The main constraint is that the light has to reach the receiver. Walls block it, so Li-Fi usually works room by room, and a device that moves out of the beam can lose its connection. Device orientation also affects performance. A standard for this, IEEE 802.11bb, was approved in 2023.

Technical explanation

Light-based links modulate the output of an LED or laser diode, and a receiver converts the incoming optical power into an electrical signal with a photodiode. LEDs have limited modulation bandwidth, so high-speed systems often use orthogonal frequency-division multiplexing (OFDM), which spreads data across many subcarriers, combined with equalisation and adaptive bit loading to match each subcarrier to the channel. Tsonev and colleagues (2014) used this approach with a single 50 µm gallium nitride LED to exceed 3 Gb/s. The abstract does not give the link distance. Jin and colleagues (2025) reported 9.06 Gb/s at 0.2 m, 8.14 Gb/s at 1 m and 6.23 Gb/s at 3 m with a green micro-LED, using SNR-gap-dependent bit and power loading. In both cases the result is for a single emitter in a laboratory link. The Jin result is only meaningful together with its distance.

IEEE 802.11bb extends the 802.11 family to light. The project covers uplink and downlink operation in the 800 nm to 1,000 nm band, which is near-infrared rather than visible light. The mandatory common-mode physical layer is based on the single-input single-output (SISO) 20 MHz profile from 802.11ax. The scope also lists hybrid coordination function (HCF) channel access, overlapping network detection and coexistence, and existing power-management modes. The working group approved the project authorisation request in January 2018, and the IEEE Standards Board approved the standard on 4 June 2023.

Uplink is a difficult part of the design. A mobile device has limited transmit power, and Dehghani Soltani and colleagues evaluate uplink energy efficiency under a transmit power constraint (arXiv preprint). Oledcomm states that its LiFiMAX Compact kit reaches up to 150 Mb/s in each direction for up to 16 users. These are maker claims, and the page does not say whether line of sight is required.

What the evidence says

Each statement is typed by the strength of its evidence and linked to the source that supports it.

Demonstrated Shown in a published experiment, test or shipping product.

The IEEE Standards Board approved IEEE P802.11bb, the light communications project for IEEE 802.11, on 4 June 2023.

Sources: [1] · Approval notification text

The 802.11bb project covers uplink and downlink operation in the 800 nm to 1,000 nm band, which is outside visible light.

Sources: [2] · Scope section

The 802.11 working group approved the project authorisation request in January 2018, and the IEEE Standards Board approved creating the light communications amendment in May 2018.

Sources: [2] · Approval and publication dates section

Tsonev and colleagues report wireless transmission above 3 Gb/s from a single 50 µm gallium nitride LED, using pre- and post-equalisation and adaptive data loading with OFDM. The abstract does not give the link distance.

Sources: [3] · Abstract

Jin and colleagues report 9.06 Gb/s at 0.2 m, 8.14 Gb/s at 1 m and 6.23 Gb/s at 3 m, with a green micro-LED, bit and power loading, and bit error rates between 3.2 and 3.7 × 10⁻³ at those distances.

Sources: [4] · Abstract

Reported, unverified Stated by a company or team but not independently confirmed.

Oledcomm states that its LiFiMAX Compact kit has upload and download rates of up to 150 Mb/s each, with up to 16 users. The page states these as maximums and does not say whether line of sight is required.

Sources: [5] · Specification section · medium confidence

Oledcomm states that LiFi relies on line-of-sight communication, that light cannot penetrate walls, that large areas may need several light sources, that LiFi is generally more expensive than Wi-Fi, and that it requires specialised hardware such as photonic antennas and receivers.

Sources: [6] · Disadvantages section

Oledcomm states that moving a device from one room to another may disrupt the connection for a few seconds.

Sources: [6] · Disadvantages section · medium confidence

Dehghani Soltani and colleagues evaluate LiFi uplink energy efficiency analytically under a transmit power constraint on the user device.

Sources: [7] · Abstract · medium confidence

Limitations and open problems

  • Line of sight and walls: light does not pass through walls, so coverage is usually limited to one room, and large areas may need several light sources, according to the vendor Oledcomm.
  • Mobility: moving a device between rooms may disrupt the connection for a few seconds, according to Oledcomm.
  • Uplink: transmit power on a mobile device is constrained, according to Dehghani Soltani and colleagues (arXiv preprint).
  • Evidence base: the high rates come from single-emitter laboratory links that use specific equalisation and bit-loading methods. They are not general room-scale rates.
  • Cost and hardware: Oledcomm says LiFi is generally more expensive than Wi-Fi and needs specialised hardware, such as photonic antennas and receivers.

Possible future uses

Speculative

Ideas, not predictions. None of these has been demonstrated.

  • Speculative: data links in hospitals, aircraft cabins or other places where radio emissions are restricted. No source reviewed here tests this use.
  • Speculative: indoor positioning that uses existing light fittings as reference points. No source reviewed here tests this use.
  • Speculative: short, room-scale links for sensitive rooms where signals should not leave the walls. No source reviewed here tests this use.

Timeline

  1. Apr 2014Tsonev and colleagues report wireless transmission above 3 Gb/s from a single 50 µm gallium nitride LED in IEEE Photonics Technology Letters. Sources: [3]
  2. May 2018The IEEE Standards Board approves the creation of the light communications amendment, after the 802.11 working group approved the project authorisation request in January 2018. Sources: [2]
  3. 4 Jun 2023The IEEE Standards Board approves IEEE P802.11bb (light communications), according to the IEEE approval notification dated 5 June 2023. Sources: [1]
  4. 27 Sept 2024Jin and colleagues publish online in the Journal of Lightwave Technology a green micro-LED link that reaches 9.06 Gb/s over 0.2 m. Sources: [4]

Futures this could help bring about

AI illustration
How far away?

Internet cables that carry light through air

Pilots · 2 of 6 steps done

Glossary

Visible light communication (VLC)
Sending data by modulating visible light, which is the wavelength range people can see.
OFDM
Orthogonal frequency-division multiplexing, a method that splits data across many narrow subcarriers so that a limited-bandwidth device can carry more data.
Micro-LED
A very small light-emitting diode that can be switched fast enough to carry high-speed data.
Uplink
Data sent from a user device back to the network. In Li-Fi it is often sent on infrared light.

Sources

  1. other
    IEEE 802.11bb approval notification (forwarded to the IEEE 802.11 mailing list)
    Karen Evangelista, Dorothy Stanley. IEEE 802.11 Working Group mailing list (STDS-802-11), 5 Jun 2023. Accessed 22 Oct 2026.
  2. other
    IEEE P802.11 Light Communication Task Group status page
    IEEE 802.11 Working Group, 22 Oct 2026. Accessed 22 Oct 2026.
  3. peer reviewed paper
    A 3-Gb/s single-LED OFDM-based wireless VLC link using a gallium nitride μLED
    Dobroslav Tsonev, Hyunchae Chun, Sujan Rajbhandari et al.. IEEE Photonics Technology Letters, Apr 2014. DOI: 10.1109/LPT.2013.2297621. Accessed 22 Oct 2026.
  4. peer reviewed paper
    Green Micro-LED With a Bandwidth Exceeding 2 GHz for 9-Gbps Visible Light Communication Based on SNR Gap-Dependent Bit and Power Loading
    Zuxin Jin, Runze Lin, Xuyang Liu et al.. Journal of Lightwave Technology, 27 Sept 2024. Accessed 22 Oct 2026.
  5. company announcement
    LiFiMAX Compact: High-Speed LiFi Kit Solutions
    Oledcomm, 22 Oct 2026. Accessed 22 Oct 2026.
  6. company announcement
    Advantages And Disadvantages Of LiFi - Complete Guide
    Oledcomm, 22 Oct 2026. Accessed 22 Oct 2026.
  7. preprint
    Bidirectional Optical Spatial Modulation for Mobile Users: Towards a Practical Design for LiFi Systems
    Mohammad Dehghani Soltani, Mohamed Amine Arfaoui, Iman Tavakkolnia et al.. arXiv, 2 Dec 2018. Accessed 22 Oct 2026.

Revision history

3 changes since this profile was created.

Changes on 22 Oct 2026
Published on owner instruction (content loop iteration 62)0bb7456
Sources and claims re-checked against originals409337d
Initial profile drafted from primary sourceseaac9eb