Design and Implementation of More Than 50m Real-Time Underwater Wireless Optical Communication System

Abstract

In this paper, the mathematical model of underwater wireless optical communication (UWOC) is built, the design method and implementation process of the system are described, and the related variables in the system design are quantitatively analyzed, which provide a theoretical basis for the system implementation and experimental verification. In the process of system implementation, three methods are proposed. In the first method (Atmospheric equivalent channel), the underwater channel can be equivalent to the atmospheric channel with the same channel attenuation, so that the power budget verification can be carried out before the system is watertight, and the flexibility of system debugging can be improved. Water quality has a great influence on UWOC, so water quality measurement in uncharted water has become a critical technology. The second method (Water quality measurement) can measure the attenuation coefficient and attenuation of unity distance (AUD) through communication experiments. The system designed in this paper can achieve 32 m/80 Mbps communication in the artificial pool (Firewater, the AUD is 0.55 dB/m by the second method), and the bit error rate (BER) is 8.6×10 <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">−6</sup> . Since the target scene is the deep sea, to reduce the difficulty of the experiment, the third method (Calculation of distance in the deep sea) can calculate the communication distance of the deep sea according to the communication distance of the experimental water. The system can complete more than 50 m/80 Mbps communication in deep sea (The AUD is 0.25 dB/m), and the BER is less than 1×10 <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">−5</sup> .