The Universitat Oberta de Catalunya (UOC) in Barcelona, Spain, is offering a fully funded PhD position focused on enabling energy-autonomous connectivity for Ambient IoT communication. The successful candidate will join the Doctoral School and work on the cutting-edge GAIA project, which aims to develop sustainable, biodegradable IoT devices with minimal ecological impact. The research will address major challenges in large-scale Ambient IoT deployments, including boosting the link budget of passive devices, developing novel backscatter mechanisms, and designing efficient energy harvesting protocols using environmental sources like solar energy. The project is coordinated by UOC faculty members Joan Melià and Xavier Vilajosana, and offers collaboration opportunities with top European labs and the possibility of an internship at Aalborg University. Applicants should have an MSc in Telecommunications, Computer Science, Electrical Engineering, or a related field, with strong programming skills and experience in wireless networks and signal processing. The position provides a 3-year full-time contract, access to advanced SDR, RF, and AIoT infrastructure, and is part of a larger initiative funded by Horizon Europe EIC Pathfinder. The interdisciplinary environment combines hardware, networks, and materials science, and supports responsible research and innovation. Applications should be sent to [email protected], including a CV, motivation letter, and academic transcript. The starting date is flexible, with a target of mid-2026.