Metoder för hantering av dynamiska interferensmiljöer

Reliable communication systems are crucial in order for the armed forces to fulfil their mission. Despite assuring electromagnetic compatibility (EMC) for subsystems on a platform, there are risks for intersystem interference. These problems can manifest both between different radio communication systems, and between a communication system and other systems vital for the mobility, effect and protection of the platform. The main objective of the project KORINT is to answer the following question: How can the required reliability of the communication systems on board military platforms be guaranteed, when compromises in system integration need to be made with the premise of not degrading the performance of the primary functions of the platform (protection, effect and mobility)? KORINT and previous projects at FOI have shown that the four most prominent factors affecting the reliability of the communication systems on military platforms are: Limited access to frequency spectrum: Affects protection against electromagnetic warfare and the ability to handling problems due to co-location and interference effectively. Insufficient standards for out-of-band emissions: Current standards are insufficient and need to be modified according to the actual demands for reliable communication systems. Insufficient management of the entire process for procurement of new (and modification of old) systems: In previous projects, the concept of a person responsible for the system integration of a platform was introduced. This concept is still valid with the addition of methodological support for making the compromises made well-documented and traceable. Too many emitters of electromagnetic radiation on small platforms: Only those systems crucial for the task of the platform should be active and the set of allowed systems should be task-specific. It is important to point out that total reliability of the communication systems on a platform cannot be guaranteed. This is because a platform is a complex system-ofsystems where factors such as legacy equipment, civilian commercial components, lack of frequency spectrum and many actors with varying knowledge and experience, leads to difficulties in procuring, using and maintaining all systems. This report is primarily concerned with dynamic situations where the electromagnetic environment and signal propagation vary over time, for instance due to changing environments or unexpected co-location scenarios. Several presented technics in the report have a potential to improve communication systems reliability, for example adaptive demodulation in impulse noise environments, dynamic spectrum and power allocation as well as full duplex techniques for reducing out-of-band emissions. In terms of methodology, our assessment is that some parts of a more systematic process that contributes to better overall system integration is possible to apply, despite the difficulties associated with such processes.