SUBCON REVIEW 2024: KEY CHALLENGES IN SUBMARINE CONSTRUCTION
The 8th Submarine Conference (SubCon) took place in Kiel from September 17 to 19, 2024. This year, the International Submarine Conference focused on global threat scenarios under the motto “SETTING THE PACE IN UNDERWATER DOMINANCE”. PLATH S&I contributed to the discussion with a presentation on “Reliable Intelligence Systems in a Complex World”, looking to the future.
Early warning capability at the highest level

One of the main challenges in submarine construction is the often very long time of up to 10 years between the start of design and delivery of the boat. As the technical possibilities develop rapidly, the overall system becomes increasingly complex. The long duration of such projects raises the question of whether technology should be delivered according to the original configuration or state-of-the-art. With this article, PLATH encourages discussion of these topics in this context: Obsolescence management, change and configuration management and the fact that technical progress does not stop after the start of a project.
Using a maritime use case, Business Case Manager Frederic Thewes demonstrated capabilities in the area of SIGINT systems (Signal Intelligence) for communication detection on state-of-the-art submarines. The units are difficult to detect and can operate covertly close to shore. In combination with a high-performance SIGINT system, this represents a new reconnaissance capability that can conduct reconnaissance of both naval forces and land-based activities. In tactical use, such a built-in system offers an early warning capability at the highest level if basic reconnaissance / intelligence has already been carried out beforehand.
At the same time, a submarine can reconnoitre maneuvers or troop movements on land and thus provide valuable insights.
Self-protection and maximized early warning time

Modern submarines have a very low self-signature for self-protection. In order to receive signals for reconnaissance, it is sufficient to record a signal sample during a brief surfacing and only evaluate this when the boat is already submerged again. This process can also be automated.
The maximized early warning time that can be achieved with a given antenna specification was carried out using a use case from the naval sector. With superstructures optimized for the platform, ships can read out data such as the energy signature or the modulation type of the communication and decode the signal content in a time window of 30 seconds from a distance of 26 NM. A further 20 seconds later, the voice and text analysis by the operator can already be completed and the transmitter can be categorized as hostile or friendly with a high degree of probability.
With one or more approaching helicopters, the reconnaissance described above can be carried out in the same time window and at distances of 144 NM or more. The optimized early warning time for helicopters is between 26 min and 64 min. The calculations are always dependent on the installed antenna height of the deployment device and the average mast heights or flight altitudes of the transmitting objects.
In a short retrospective, the 70 years of experience that PLATH has in radio reconnaissance were looked back on. In the middle of the last century, one sensor was required for each signal. Automation did not yet exist; the operator had to remain seated at the device in order not to miss the decisive signals after hours of radio silence. As the number of functions of the receivers and sensors increased, additional control units were required, which still took up a lot of space. This technology was still too large for submarines. Today, the systems are not only much smaller and can therefore be installed in submarines as well as smaller aircraft, they also support the operator extensively with automated functions. After automatic classification and demodulation of signals, manual evaluation can be prepared by decoding known signals and preparing unknown signals for evaluation. New features are constantly being added to further improve support for evaluation. These include AI speech enhancement, voice identification, network identification and reporting.
Collaborative design approaches
When looking at collaborative design approaches with other partners, the first thing to realize is that system engineering is a process in which every step must be executed for the project to be successful.
When integrating the systems, the required functions define the necessary sensor hardware and these sensor hardware functions then define the necessary software capabilities. Finally, the software requirements result in the necessary server performance. The submarine builder's engineering team then needs these server and sensor hardware configurations to design the vessel. It should be emphasized here that PLATH S&I, as an independent system integrator, does not limit itself to hardware from the PLATH Group, but always makes use of all the latest technologies available on the market in order to implement customer wishes and mission requirements in a cost-efficient and modern way.
While the speaker discusses the current system design for submarines, he mentions the massive server footprint that current systems leave behind, both for systems that are only used for reconnaissance of content and especially those that also enable direction finding or tracking. Depending on the frequency, the latter require larger antennas and the server power correspondingly more energy for the calculations, which results in increased waste heat. The optimal design and configuration of such systems, taking into account the application scenario, is one of the core elements of the PLATH Systems & Integration experts.
The integration of SIGINT systems goes hand in hand with system-to-system integration, such as the connection to the CMS. The immense number of interfaces and functionalities, as well as the dependencies of certain signals and cycles, increase the level of complexity. In the mission system, weapon control and the compilation of sensor data for a reliable, evaluated maritime situation picture (Recognized Maritime Picture) and the EW/SIGINT cluster must be coordinated with each other.
Change and obsolescence management
Of central importance

Change and obsolescence management, whose core elements were outlined in the presentation, are also of central importance. The message of PLATH is summarized in one sentence: As changes become more expensive if they are implemented later, it is advisable to discuss desired functions and requirements as early as possible. For example, if further functions are desired that require additional server power, the cooling concept will need more capacity. Even small changes to subsystems can have an impact on the auxiliary systems.
As soon as hardware is defined, it should be included in obsolescence management. This also applies to software, which must be updated as soon as it is released in order to remain maintainable during the platform's service life.
Therefore, contact the experts as early as possible in the process. PLATH S&I is a trusted advisor in this area and can contribute from design and conceptualization to implementation.
New architectural design approaches in the context of Software Defined Defense
In the following, we would like to explain the concept of virtualization of server hardware in the context of submarine construction. While in previous generations each subsystem had its own server, which was selected individually for the performance of the system and therefore generally meant different types, the concept of virtualization already exists in the construction phase.
The software of the subsystems runs on a server landscape provided by the system integrator. Software Defined Defense means that the software of the subsystems works in containers, similar to applications on a cell phone.
PLATH makes a contribution to development and uses containers in this approach, which will make it easier to exchange software and hardware. This also results in a smaller server footprint.
The advantage of this system approach is the decoupling of hardware and software. This makes it easier to adapt the software. Other advantages include optimized data storage, additional applications for evaluation and the ability to remove unnecessary components in order to keep the system efficient. In summary, it can be said that the standard containers are still under development. But if there is a need among end users to shape this concept, now is the time to get involved!
New types of communication require new sensors

More information is being exchanged through new means of communication. For example, the role of satellite-based communication in the maritime sector is increasing rapidly. Possible destinations now use additional frequency bands or use existing ones differently. For example, mobile phone networks must now also be taken into account when communicating on ships. Further functions are possible due to technical improvements.
If, for example, UAVs (Unmanned Aerial Vehicles) are controlled from ships, the signals are completely different, as is the way they use the frequency. However, technical progress also enables COMINT with submarines far beyond the line of sight and the 12 nm zone by further improving the hardware.
Typical procurement cycle for a permanently installed COMINT system
Finally, we would like to make a small digression on the typical procurement cycle for a permanently installed COMINT system. In relation to the Naval platform, this can be ten years or more. We would like to mention that PLATH has its rapidly deployable platform-independent system NEMO in its portfolio. It enables the same functionalities of precise reconnaissance and evaluation of signals in the area of interest. The mobile, turnkey NEMO solutions offer automatic signal detection, broadband direction finding, recording and automatic decoding. Contact the PLATH team to discuss the rapid deployment of a demo system for your platform.
To summarize, three points are central:
Technical development
Technical progress requires a new concept for the sensor system - this represents an opportunity to realize flexibility and upgradeability
Future threats will change
Current conflicts show that sensor capabilities need to be quickly adapted to new emitters and patterns
AI will change our operational principles of fraud prevention
A system design based on the concept of Software Defined Defence offers the opportunity to easily integrate AI and enable customization along the development.
About PLATH S&I
PLATH's Business Division Systems & Integration (S&I) is the central hub for the realization of systems for data-based early crisis detection and addresses these issues. Its experts implement systems for various platforms and applications according to customer requirements.