Digital underwater communication in maritime shipbuilding
03 March, 2021
In recent years, many efficient transmission methods have been developed for mobile communications. Electromagnetic waves for wireless data transmission now enable large bandwidths and data rates of several GBit per second in this area - even over long distances.
Digital underwater communication is an exception. We spoke to Dr. Till Wiegand, Head of Center of Competence "Underwater Communications" and Senior Systems Engineer at our subsidiary ATLAS ELEKTRONIK, about the challenges of digital underwater communications and the development of a holistic solution for communication via sonar antennas.
Working together for successful underwater communications
Dr. Till Wiegand heads the Center of Competence Underwater Communications at thyssenkrupp Marine Systems. In his team, experts from various disciplines are driving the topic of digital underwater communications forward.
The task of the Center of Competence is to take a holistic view of the potential of various technologies for underwater communications and to bundle activities within thyssenkrupp Marine Systems.
The challenges of digital communication under water
Compared to mobile communications, technologies for digital underwater communications have to serve quite different conditions. "Due to difficult propagation conditions, we cannot simply adopt the standard procedures of mobile communication for underwater use," explains Dr. Till Wiegand. "Instead, we have to use sound waves in the lower frequency range of a few Hz to a hundred kHz to bridge large distances." However, this frequency range only allows a low bandwidth and correspondingly lower data rates.
This is where digital underwater communication comes into play. It enables the transmission of digital information via sound waves using digital modulation methods. The overriding goal of the experts at thyssenkrupp Marine Systems is to integrate submerged underwater vehicles - especially submarines - in networked operations. "In this context, digital underwater communications is an enabler technology for expanding operational capabilities and developing new applications," says Wiegand. "Key drivers are the support of modern cooperative positioning procedures, the exchange of tactical information and situational awareness, and the possibility of machine-to-machine communication, e.g., in emergency situations."
The experts are currently developing an integrated component for sonar systems in upcoming projects. "The use of highly sensitive submarine sonar antennas promises a significant performance gain compared to standard systems with only single or a few hydrophones," explains Wiegand. A critical research project for cross-media communication is a wireless gateway buoy that could be used as a universal link between mobile surface and subsea units.
From point-to-point communication to adaptive networks
In addition, navies also place increasing importance on networked operations in underwater communications, says Wiegand. Communications must increasingly include unmanned underwater vehicles. "Communication methods are increasingly evolving from a pure point-to-point connection to adaptive networks that must allow for a flexible number of users and constantly changing environments," adds the expert. Also, the aspect of tap-proof and encrypted transmission is gaining importance. In special applications, communication must take place covertly.
Dr. Till Wiegand, Head of Center of Competence "Underwater Communications" at ATLAS ELEKTRONIK GmbH
Networks can include autonomous underwater vehicles that independently forward their recorded information to cooperating units. thyssenkrupp Marine Systems is already represented as an industrial partner in this field in the Smart Adaptive Long- and Short-range Acoustic Network (SALSA) project of the European Defence Agency (EDA) with a total of five participating nations.
According to Dr. Till Wiegand, the extent to which digital underwater communication will be used in the maritime sector in the future depends not only on research of the necessary methods, but also on national and international standardization in this area.
"Different communication procedures have already been developed by individual nations in recent years," continues Wiegand. Among them were two NATO standards that are already represented in upcoming thyssenkrupp Marine Systems projects. The experts in Wiegand's team are actively accompanying this process and developing algorithms and systems for the most promising procedures.
A system house for holistic solutions
In the future, digital underwater communication is to become an integral part of existing and future thyssenkrupp Marine Systems products. "Our aim is to be able to offer holistic solutions for naval shipbuilding as a systems house," says Wiegand. Here, both bidirectional underwater-to-underwater and surface-to-underwater communication capabilities will play a crucial role.
At thyssenkrupp Marine Systems, digital underwater communication is the responsibility of the subsidiary ATLAS ELEKTRONIK. As experts in hydroacoustics, sensors and information technology, ATLAS ELEKTRONIK is the preferred supplier to numerous naval and civilian customers worldwide and is the market and technology leader for underwater acoustics.