Euronaval 2024 – SeaShield, an underwater coastal surveillance sonar by DSIT Solutions of Israel
DSIT Solutions, the Rafael subsidiary specialised in defensive systems against underwater threats, unveiled at Euronaval 2024 its SeaShield fixed very long-range underwater coastal surveillance sonar
“Detecting submarines at very long distances has been until now a capability in the hands of superpowers, due to its cost. With our SeaShield we give the opportunity to a wide range of potential customers to acquire a similar capability at a very affordable price,” Amir Alon, Vice-President Marketing and Business Development at DSIT Solutions tells EDR On-Line in one of the few Israeli booths present at Euronaval, as the companies of that nation were given the green light for participating in a “degraded mode” to the Paris naval exhibition only a few days before this opened its doors at the Parc des Expositions in Villepinte, at short distance from the Charles de Gaulle airport.
The SeaShield™ was designed to increase the underwater domain awareness, which aims first to detect submarines. “Our system is a tailor-made solution, and therefore two systems will never be identical, as when we design it, we consider the customer arena as well as well as the threat he considers,” Amir Alon explains.
It is quite obvious that the shallow waters of the Baltic Sea are quite different from those of the Mediterranean which are dissimilar from that of other oceans or seas. “To finetune our product we play with the transducers, with the frequencies, to reach the best performances,” he adds. Should the main threat come from underwater unmanned vehicles (UUVs) or swimmer delivery vehicles (SDVs) DSIT Solutions would adapt its system to targets much smaller than conventional submarines that operate at different speed.
The SeaShield comes in the form of two horizontal receive linear arrays with a length of around 40 metres each, deployed at an angle of 240°, with a vertical transmit array at their interception. The latter, which is 3 metres high with a diameter of around 1 metre, emits omnidirectional high source-level standard and coded pulses; to simplify maintenance DSIT kept ashore as many components as possible, therefore transmit power amplifiers are installed on land, acoustic energy being transferred to the transmit array via an underwater cable. The system can operate in passive mode, its receiving arrays ensuring detection and classification based on DEMON (Detection of Envelope Modulation on Noise), narrowband analysis and audio. When the transmit array is activated detection and classification are based on Doppler, target size, target dynamics and imagery. “We can do DEMON and we can do active imagery of every contact, as we have very sophisticated algorithms that help the operator in the decision process of the classification,” Amir Alon tells us, adding that these algorithms obviously contain some artificial intelligence elements, including machine learning, the latter allowing automatic database updating as well as constant improvements in the knowledge of the specific arena conditions, the mammals present in the area, etc.
The SeaShield can obviously be integrated with other systems, providing a multi-layered defence structure. “We can for example deploy our AquaShield Diver Detection Sonar System, which has a relatively short range, around 1 km against divers, and can be installed inside ports, naval bases, or onto oil and gas rigs. Then comes the Long Range AquaShield, which is more oriented towards midget submarines, SDVs and large UUVs, which can be detected at around 5 km. Then comes the SeaShield, which range is over 50 km,” the DSIT Business Development Manager says, EDR On-Line understanding that tests have proved ranges well over those declared. The next step will be to connect all this into a network.
Beside the obvious defensive advantages, the SeaShield provides also other advantages. It can for example allow sending messages to one’s own submarines, allowing them to navigate with utmost accuracy, the active “ping” acting like a beacon. Sea bottom surveillance is another possible use, quite popular nowadays. “One of the other aspects of our SeaShield is that it is a strong deterrence asset,” Amir Alon says. “The sonar ‘ping’ can happen at random intervals, hence the enemy cannot know if and when this will happen, which generates uncertainty in the opponent.
Deploying the SeaShield allows reducing considerably the use of antisubmarine warfare naval and air assets, which permits considerable saving. To keep the cost under control, DSIT Solutions strongly advises to deploy the wet end installation at 30 metres depth, which allows divers with standard compressed air bottle to reach the system for maintenance.
With a customer already using the system, now DSIT Solutions is strongly promoting its SeaShield, which was unveiled at the Paris exhibition.
Image courtesy DSIT Solutions
