• iot systems
• meandered pifa antenna
• rectenna
• rf energy harvesting
• ultra-low power chip
• wireless power transfer

This thesis investigates radiofrequency energy harvesting (RF-EH) and wireless power transfer (WPT) as enabling technologies for battery-less IoT nodes. The work begins with an overview of the transition from battery-assisted systems to energy-autonomous devices, highlighting the main energy harvesting techniques and their role in the development of sustainable and long-lasting IoT solutions. A focus is placed on rectenna-based architectures, discussing their fundamental components, antenna, matching network and rectifier, and positioning them within the context of existing literature and commercial solutions.

Building on this foundation, the thesis proposes two rectenna designs optimized for distinct operating conditions. The RF-EH rectenna is tailored for very low input power scenarios, enabling the supply of simple sensing and lightweight computation tasks. The WPT rectenna, instead, addresses higher input power levels to support more complex operations, while both solutions share a common antenna design and diverge only in their rectification stages.

Finally, experimental measurements are conducted on the AX-E0 microprocessor developed by Arox, a custom ultra-low-power chip designed for IoT applications. By testing different workloads, the feasibility of integrating RF-EH and WPT with real computational platforms is evaluated, demonstrating a flexible strategy for adapting energy availability to the computational demands of next-generation IoT devices.