Li-Fi Based Autonomous Underwater Vehicle with Integrated Optical Communication and Obstacle detection

Subha Priyadharshini; Chandrasambavi SM; Kabilesh C; Krishnapreetha M; Vignesh C

doi:10.29284/8m485457

Authors

Subha Priyadharshini Department of Electronics and Communication Engineering Coimbatore Institute of Technology, Coimbatore, Tamilnadu, India
Chandrasambavi SM Department of Electronics and Communication Engineering, Coimbatore Institute of Technology, Coimbatore, Tamilnadu, India
Kabilesh C Department of Electronics and Communication Engineering, Coimbatore Institute of Technology, Coimbatore, Tamilnadu, India
Krishnapreetha M Department of Electronics and Communication Engineering, Coimbatore Institute of Technology, Coimbatore, Tamilnadu, India
Vignesh C Department of Electronics and Communication Engineering, Coimbatore Institute of Technology, Coimbatore, Tamilnadu, India

DOI:

https://doi.org/10.29284/8m485457

Keywords:

Autonomous Underwater Vehicle (AUV), On-Off Keying (OOK), laser Li-Fi, radio frequency (RF)

Abstract

Underwater communication remains a significant challenge due to the severe attenuation of radio frequency signals in water. This paper presents the design and implementation of a compact underwater obstacle detection and real-time image transmission system using laser-based Light Fidelity (Li-Fi) technology. The proposed system employs a Raspberry Pi Pico microcontroller to coordinate obstacle detection, optical modulation, and signal processing. A laser-based reflection mechanism is utilized to detect obstacles within short range underwater environments. Upon detection, an image of the obstacle is captured and enhanced using contrast improvement and edge enhancement techniques to improve visibility under low-light and scattering conditions. The processed image is resized and converted into binary format for efficient transmission. The binary data modulates a laser diode, where ON–OFF keying represents digital ‘1’ and ‘0’ states, enabling optical wireless communication through the water medium. At the base station, a photodiode coupled with an amplification circuit detects the modulated laser pulses and reconstructs the transmitted image. The received image is displayed on an embedded LCD and a PC interface for monitoring purposes. Experimental evaluation in controlled water conditions demonstrates reliable short-range data transmission with improved image clarity through enhancement techniques. The proposed system offers a low-cost, energy-efficient, and scalable solution for underwater robotics, vessel monitoring, marine inspection, and surveillance applications, providing an alternative to conventional acoustic or wired underwater communication systems.

References

[1] A. Al Guqhaiman, O. Akanbi, A. Aljaedi, and C. E. Chow, “A survey on MAC protocol approaches for under water wireless sensor networks,” IEEE Sensors Journal, vol. 21, pp. 3916–3932, 2021.

[2] A. Saha, S. Chatterjee, and A. Kundu, “Analysis on data transmission using Li-Fi,” in Proc. 1st Int. Conf. Convergence in Engineering (ICCE), 2020, pp. 352–356

[3] R. Bharathi and T. R. Megha, “An image transfer using NI-USRP,” International Journal of Engineering Applied Sciences and Technology, vol. 5, no. 4, pp. 191–195, 2020.

[4] R. Devi Priya, R. Sivaraj, A. Abraham, T. Pravin, P. Sivasankar, and N. Anitha, “Multi-objective particle swarm optimization based preprocessing of multi-class extremely imbalanced datasets,” International Journal of Uncertainty, Fuzziness and Knowledge-Based Systems, vol. 30, no. 5, pp. 735–755, 2022

[5] E. Ifada and N. T. Surajudeen-Bakinde, “Implementation of a data transmission system using Li-Fi technology,” in Proc. 2nd Int. Conf. IEEE Nigeria Computer Chapter, vol. 1, 2019, pp. 1–7.

[6] C. Gamal, M. Elsayed, A. Samir, H. A. Tageldien, S. Chatzinotas, M. M. Fouda, and B. M. Elhalawany, “Reliability of spectrum-efficient mixed satellite-underwater systems,” IEEE Open Journal of the Communications Society, vol. 3, pp. 2237–2244, 2022.

[7] N. S. Harikant, M. A. K. P., M. A. V., N. Sridhar, and K. Venkateswaran, “Development of data transmission model for underwater communication using Li-Fi technology,” in Proc. 5th Int. Conf. Communication and Electronics Systems (ICCES), 2020, pp. 317–321.

[8] S. Salvi, V. Geetha, H. Maru, N. Kumar, and R. Ahmed, “An image transmission technique using low-cost Li-Fi test bed,” in Proc. 2nd Int. Conf. Secure Cyber Computing and Communications (ICSCCC), 2021, pp. 114–119.

[9] S. Sandoval-Reyes, “Transmission and reception of text and images using visible light,” in Proc. Centro de Investigación en Computación, Instituto Politécnico Nacional, Ciudad de México, Mexico, pp. 335–345, 2019.

[10] G. Wu, T. Xu, Y. Shun, and J. Zhang, “Review of multiple unmanned surface vessels collaborative search and hunting

based on swarm intelligence,” International Journal of

Advanced Robotic Systems, 2022.

[11] Y. Ata, H. Abumarshoud, L. Bariah, S. Muhaidat, and M. A. Imran, “Intelligent reflecting surfaces for underwater visible light communications,” IEEE Photonics Journal, vol. 15, no. 1, pp. 1–10, 2023.

[12] M. Zhang and H. Zhou, “Real-time underwater wireless optical communication system based on LEDs and estimation of maximum communication distance,” Sensors, vol. 23, no. 17, pp. 7649, 2023.

[13] Y. Mou and S. Liu, “Channel estimation for underwater visible light communication: A sparse learning perspective,” in Proc. IEEE Int. Conf. Communications Workshops (ICC Workshops), May 2023, pp. 943–948.

[14] M. Janarthanan and S. Gauni, “Optimization of underwater visible light communication transmission using multilevel regression modelling,” Ocean Engineering, vol. 309, pp. 117988, 2024.

[15] Y. Di, A. Xu, and L.-K. Chen, “Performance enhancement via real-time image-based beam tracking for WA-OWC with dynamic waves and mobile receivers,” Journal of Lightwave Technology, vol. 42, no. 19, pp. 6671–6678, 2024.

[16] S. Rehman, Y. Rong, and P. Chen, “Designing an adaptive underwater visible light communication system,” Sensors, vol. 25, no. 6, pp. 1801, 2025.

[17] K. Kuwahara, K. Tanaka, A. Kariya, S. Hayashida, and T. Kodama, “Underwater invisible light communication network with beam steering technology for dynamic switching between aerial and underwater optical paths,” Sensors, vol. 25, no. 4, pp. 1053, 2025.

[18] V. L. Jayaweera et al., “Visible light communication for underwater applications: Principles, challenges, and future prospects,” Photonics, vol. 12, no. 6, 2025.

[19] C. Subha Priyadharshini, C., & A. Rajeswari,” High-Capacity Optical Communication Systems using 4D Spatial-Wavelength-Zero Cross Correlation Encoding”. IETE Journal of Research, 71(8), 2593–2605, 2025.

[20] V. L. Jayaweera et al., “Visible light communication for underwater applications: Principles, challenges, and future prospects,” Photonics, vol. 12, no. 6, 2025.