DC7 – Physical Layer Security using Directional Modulation

1. MSCA Mobility rule

To be eligible for this PhD position, applicants must not have resided or carried out their main activity (work, studies, etc.) in the country of their first recruiting beneficiary (France or United Kingdom) for more than 12 months during the 36 months immediately preceding the recruitment date — unless this period was part of a compulsory national service or a procedure for obtaining refugee status under the Geneva Convention.

2. Description of the Work Project

Physical layer security is becoming increasingly critical in emerging satellite networks, which support vital services like global communications, Earth observation, and resilient navigation. Unlike
traditional encryption methods that rely on computational complexity and are vulnerable to future
quantum attacks, physical layer wireless security technologies encrypt the conveyed information
through the physical properties of radio signals themselves. This can be achieved by employing either the inherently random nature of wireless channels or the purposely generated random signals. This approach offers a quantum-resistant safeguard, as it does not depend on mathematical problems that quantum computers could crack efficiently. In satellite systems, where long-range links and open broadcast environments heighten exposure to eavesdropping and jamming, physical layer security provides a lightweight, scalable, and inherently robust defence mechanism. As satellite constellations expand and interconnect, embedding security directly into the physical transmission layer ensures enduring protection against both current and next-generation threats.
Advancing physical layer security in satellite networks requires an interdisciplinary approach, with
a strong emphasis on the joint development of radio frequency (RF) hardware and signal processing techniques. Unlike terrestrial systems, satellites operate in highly dynamic and often unpredictable environments, where rapidly changing channel conditions and long-range vulnerabilities can be exploited by adversaries. Achieving secure and reliable communication under these conditions demands RF front-ends capable of adapting to environmental variations while maintaining signal integrity and confidentiality—necessitating innovations in antenna design, beamforming, and frequency agility. At the same time, signal processing methods must evolve to compensate hardware imperfection and signal dynamics, e.g. the changing Doppler effects. The role of AI is also an emerging enabler. Because hardware performance and algorithmic strategies are deeply interdependent, independent development is inadequate; instead, integrated design methodologies are essential to create practical and resilient physical layer security solutions across diverse satellite architectures and mission requirements.

3. Core activities

1. Identify a use case where physical layer security can provide added value to existing or emerging satellite services
2. Investigate suitable analogue, RF and digital technologies that provide pertinent solution for this use case
3. Demonstrate by means of experimental and simulated results the performance of the proposed physical layer security system