• Oleksandr Romanov Institute of Telecommunication Systems of Igor Sikorsky Kyiv Polytechnic Institute, Ukraine
  • Gleb Miklaiv Institute of Telecommunication Systems of Igor Sikorsky Kyiv Polytechnic Institute, Ukraine



Light-Fidelity (Li-Fi), throughput, feedback, refresh interval, VLC


Background. Wi-Fi has many disadvantages, such as how the maximum bandwidth is limited by the frequency of the range. The work uses Li-Fi technology, which uses visible light for data transmission. The frequency range of Li-Fi is 1000 times greater than the entire radio range. Feedback is used to increase the throughput. But the feedback decreases the bandwidth of the downstream signal.

Objective. The purpose of the paper is to analyse what parameters are advisable to change to increase the throughput of the Li-Fi system.

Methods. Study of the simulated dependence of the optimal interval change for using the feedback, and using this interval plot the dependence of the throughput on the change in the parameters of the Li-Fi system with a mobile user.

Results. With an increase in the area of the photodiode and its refractive index, the throughput increases. As the receiver speed increases, the throughput decreases slightly <0.1%. Reducing the angle of the photodiode field of view and the half-angle of radiation significantly increases the throughput (by 50%) only when decreasing to small angles (<10 °).

Conclusions. It is advisable to make photodiode from a material with a high refractive index, with a big area. Since mobile devices are often used in the office Li-Fi network, it is not advisable to reduce the receiver's viewing angle, as well as to reduce the half-angle of radiation. It may also be beneficial to give mobile users more download throughput than upload throughput.


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