4-FSK High-Speed Underwater Acoustic Communication System

Oceans all over the world are an important way of sustainability in the lives of many people and have a high impact on the economy of most of the coastal countries. With the growth of underwater activity provided by the development of autonomous and remotely controlled vehicles and with the appearance of new underwater sensors, there is also a need to develop and design more robust underwater wireless networks to provide better and faster communications among the devices connected to the network. Nowadays several technologies provide wireless underwater communications. In this work, we address acoustic technology and the implementation of an acoustic communication system which applies a version of frequency modulation. The main goal of this work is to study the 4-FSK modulation technique and verify the efficiency of the communication system according to variables such as communication distance and baud rate. This implementation uses FPGA systems and Xilinx Vitis Model Composer software and MATLAB Simulink software for simulation. The developed communication system was tested in a controlled environment at two stages: aquarium and pool. The tests were carried out transmitting at 3 different baud rates (40, 100 and 200 kbps) in a distance of 100 cm in the aquarium and 5 meters in the pool.