Abstract
Aim: this paper discusses a VLC system with a simple and cheap model design for transmitting audio and digital signals using LiFi technology to illustrate Li-Fi technology, which has become the future of wireless communications.

Methods: Visible light communication (VLC) is wireless communication using visible light as a means of transmitting information. Light is an electromagnetic wave with a wavelength ranging from 375 Nm to 780 Nm or a frequency spectrum ranging from 400 Hz to 800 Hz. Thus, it has become an important pillar and requirement in the development of wireless communications, and therefore, it has become one of the foundations of 5G communications. In the VLC system, the light-emitting diode (LED) is used as a transceiver to send and receive data, not to mention as lighting. The LED has a longer lifespan, low power consumption, a high tolerance to moisture, and a smaller size. So, it is more environmentally friendly and does not cause any harm to living organisms. And as the LED is used for lighting, it can also be used for communication. Thus, they are growing rapidly due to low energy consumption and high efficiency.

Results: The prototype was successful in achieving the aim of this study. As the VLC audio transceiver using an optical transceiver has been designed to demonstrate the functioning of the VLC system. The analysis of the designed system and output is presented. The designed system by using a microcontroller overcomes the critical problem with occurrence due to the intensity of the background light.

Conclusion: The field of data transmission needs rapid and effective development due to the large amount of data required to be transferred quickly to meet technological developments, especially in communications and data transmission applications. This will not be achieved using current technologies, but they must be developed, such as using the light field. Therefore, Li-Fi has become a pillar of harmless development and rapid and effective progress. Light also has a wide spectrum, which allows different uses in the transmission, reception, and monitoring of various types of data, as well as in the generation, production, and transmission of energy. Light is also capable of transmitting data at an incredible speed compared to other media used for this purpose, such as metals and electromagnetic fields. Thus, it became the recommended light field.

Key words: Light Fidelity (Li-Fi), Visible Light Communication (VLC), light-emitting diode (LED), Photodiode, Field Programmable Gate Array (FPGA), Audio communication, Digital Signal Communication.