Abstract

Communication systems are not as advanced in water as they are in the air, which leads to numerous difficulties in underwater communication. The aim of this work was therefore to develop a wireless communication system for underwater use. In the course of my work, ultrasonic waves turned out to be the most suitable carrier waves for this application, as they have both a high data transmission rate and a long range.

The piezoelectric effect was used for underwater communication, as it allows the mechanical ultrasonic waves to be translated into a measurable voltage. Since PVDF films and PZT ceramics exhibit this effect, these two materials were used for the construction of a transmitting and receiving antenna.

My work covers the construction of the ultrasonic antennas, experiments related to communication using ultrasound, various data transmission attempts and the construction of a submarine controlled by ultrasound. A frequency generator, oscilloscope, spectrum analyser, 3D printer and various additional circuits were used for this purpose.

The conclusion of this work is that communication with ultrasound is possible and that data can be transmitted precisely. PVDF resulted in a more specific antenna that is sensitive to 100 kHz and PZT in one with a larger bandwidth. The PVDF antenna was used for further applications as it was able to receive the data more precisely and interfering signals were filtered out more effectively. This communication system could be applied to various applications in the field of metrology, ultrasonic control of equipment and general transmission of information.