FUSION EXPERTISE FOR BETTER GLOBAL CONNECTIVITY

This story is about expertise developed in fusion research and later applied in a different domain. Julio Calvo built this background during his PhD at CIEMAT, the Spanish public research centre for energy, environment and technology, and later expanded it at CERN. Today, he applies it at the International Telecommunication Union, where spectrum management requires rigorous modelling, analysis, and software development.

The starting point was the fusion research environment linked to the IFMIF DONES programme. At CIEMAT, Julio Calvo worked on the design and implementation of control systems for linear accelerators used to test materials for future fusion reactors. This work required a strong combination of physics, engineering, computation, and system validation in a demanding technical setting.

Partial view of LIPAc, the Linear IFMIF Prototype Accelerator, at the Rokkasho BA site in Aomori, Japan. LIPAc is a joint EU–Japan project aimed at validating the design of the IFMIF deuteron accelerator up to 9 MeV / 125 mA CW and provides the operational context for the control system developed throughout Julio Calvo's doctoral thesis.

His expertise later grew at CERN, where he contributed to simulation tools such as TRACS. These tools were used to model charge transport and radiation damage in silicon detectors operating in intense radiation environments. This work strengthened his experience in numerical modelling, C++ programming, data analysis, and the validation of complex electromagnetic systems.

Transient Current Technique (TCT+) station of the Detector Technologies group at CERN. A focused pulsed laser injects charge locally into the silicon detector while the induced transient current is recorded at the electrodes; these measurements are the ones reproduced and fitted by the TRACS simulator, developed by Julio within the RD50 collaboration during his fellowship at CERN, following his previous work at CIEMAT and EUROfusion.

Today, this background is used in a different context. At the ITU, Julio Calvo applies these methods to technical studies on spectrum use, compatibility between terrestrial and satellite systems, and software tools that support international coordination procedures. The subject is different, but the underlying challenges are similar: complex physical interactions must be analysed carefully, results must be robust, and decisions must rely on sound technical evidence.

The value of this background is significant. Methods developed in fusion and accelerator research help improve the accuracy and reliability of technical assessments in telecommunications. This supports better decisions, reduces the risk of interference between systems, and strengthens the technical capacity of the ITU in a field where precision is critical.

The impact reaches beyond technical level. Reliable spectrum management supports mobile communications, satellite services, navigation, climate monitoring, and emergency response systems. In that sense, expertise developed for fusion research now contributes to a more efficient and more equitable use of a shared global resource.

This case also shows the broader value of fusion research. It trains experts able to work on complex physical systems, manage uncertainty, and develop robust software tools. These capabilities are highly transferable and can create value far beyond the original research field.

The ITU Radio Regulations (2020 edition). These four volumes, Articles, Appendices, Resolutions and Recommendations, and ITU-R Recommendations incorporated by reference form the international treaty that governs how countries share the radio-frequency spectrum and satellite orbits. At the ITU Radiocommunication Bureau (BR), Julio works on the TerRaSys software which supports the coordination, notification and recording procedures for terrestrial systems submitted by administrations under these rules, applying the C++ skills he acquired and refined throughout his doctoral thesis.