Li-Fi, short for Light Fidelity, is a wireless communication technology that uses visible light, infrared, or ultraviolet spectrum to transmit data, unlike Wi-Fi, which relies on radio waves. It works by modulating the intensity of light emitted by LEDs (or similar light sources) at extremely high speeds, imperceptible to the human eye, to encode and transmit data.
A photodetector, such as a photodiode in a receiving device, captures these light signals and converts them back into data.
Important Features of Li-Fi:
• Speed: Li-Fi can achieve data transfer rates exceeding 100 Gbps in lab conditions, significantly faster than typical Wi-Fi speeds.
• Security: Since light cannot penetrate walls, Li-Fi signals are confined to a specific area, reducing the risk of unauthorized access compared to Wi-Fi.
• Interference: Li-Fi operates in the light spectrum, avoiding the crowded radio frequency spectrum, thus minimizing interference from other devices.
• Applications: Suitable for environments where radio signals are impractical, such as hospitals, aircraft, or secure facilities. It’s also explored for high-speed internet in homes, smart cities, and underwater communication.
Limitations of Li-Fi:
• Line-of-Sight: Li-Fi requires a direct or reflected line of sight between the transmitter and receiver, as light cannot pass through obstacles.
• Range: Limited to the area illuminated by the light source, typically a few meters.
• Infrastructure: Requires compatible LED lighting systems and receivers, which are not yet widely adopted.
Li-Fi is still in the developmental phase, with ongoing research and pilot projects, but it’s not yet a mainstream alternative to Wi-Fi. It’s often considered a complementary technology for specific use cases rather than a full replacement.