Today, in connection with the growing interest in the resources of the world ocean, there is also interest in wireless underwater communication systems. There are programs dedicated to researches in the field of telecommunication systems for solving the problems of the Technology Platform “Ocean Development”. Wireless optical communication lines have great potential for development – this is the only technology that can be used to create a high-speed communication channel in an aquatic environment.
The key advantages of this type of communication are:
– high speed of information transfer;
– stealth, inability to listen;
– mobility, there is a connection between mobile objects.
– data collection from stationary sensors (sensor networks);
– control of unmanned underwater vehicles (collection and transmission of information, setting the survey route);
– group communication of automated unmanned underwater vehicles.
In 2013, Mostcom CJSC conducted a research on the development of a wireless optical communication system. The result of the work was the working mock-up, at which the tests, necessary to confirm the correctness of the laid technological solutions and the prospects for the further development of the PIC systems, were carried out.
Experimental measurements were carried out under laboratory conditions and in full-scale tests.
In the laboratory, radiation was passed through an 800-mm-long aquarium filled with the test liquid. The line budget, the spatial characteristics of the receiving and transmitting channels were measured to determine the requirements for the guidance system and the algorithms for processing target designations, as well as the possibility of transmitting the video image in real time.
To simulate different types of water, a solution of magnesium oxide (MAALOX) was used. This substance has a small absorption coefficient, but it also models the scattering processes well. For different concentrations, the angular parameters of the transceivers
Full-scale tests were conducted in a swimming pool. Two transceiver modules were placed at a depth of about two meters and at a distance of 15 meters from each other. In this position, the entire system was inspected, including the hermeticity of the enclosure
The results of our tests shows, that:
There is real technical feasibility and economic efficiency of the underwater wireless optical communication line;
Underwater free-space optics terminals will be competitive in comparison with wired fiber-optic communication lines that limit the maneuverability of underwater robotic objects and their dynamic operation capabilities, including the joint operation of several underwater objects.