In a remarkable feat of engineering, researchers have unveiled a Wi-Fi receiver chip designed to withstand the extreme conditions found inside a nuclear reactor. This innovation aims to facilitate wireless communication for robotics deployed in the challenging task of decommissioning reactors.
Robust Design for Harsh Environments
Presented by Yasuto Narukiyo, a graduate student at the Institute of Science Tokyo, at the IEEE International Solid-State Circuits Conference (ISSCC) in February, this receiver has withstood a radiation dose of 500 kilograys, far exceeding the tolerance levels of conventional electronics used in outer space.
The impetus for this development arose after the 2011 Fukushima Daiichi disaster, which highlighted the need for robots to assist in site characterization and cleanup. Traditional methods often rely on local area network (LAN) cables, which can become tangled and cumbersome. Narukiyo’s team, including advisor Atsushi Shirane and Masaya Miyahara from Japan’s High Energy Accelerator Research Organization (KEK), is working towards a wireless system that can effectively control robots in these hazardous environments.
The Need for Decommissioning Solutions
As nuclear power plants age, the necessity for safe dismantling and decontamination becomes critical. According to a 2024 study, of the 204 reactors that have been closed, only 11 with a capacity over 100 megawatts have been fully decommissioned. With 200 more reactors projected to reach the end of their operational lifetimes within the next two decades, the demand for robotic assistance is increasingly urgent.
Engineering Innovations in Radiation Hardening
To enhance the resilience of the 2.4-gigahertz Wi-Fi receiver against radiation, the research team modified its component mix, reduced the number of transistors, and adjusted the geometry of the remaining transistors. The silicon MOSFETs used in the design are particularly susceptible to radiation damage, as gamma rays can trap positive charges in the oxide layer, leading to performance degradation.
By increasing the size of the transistor gates and minimizing the use of PMOS transistors, which are more vulnerable to radiation, the team improved the receiver’s durability. They tested the device by exposing it to radiation sources, measuring its performance before and after exposure to doses of 300 kGy and 500 kGy. Post-exposure results indicated a minor performance drop of approximately 1.5 decibels at the highest dose.
Looking ahead, Narukiyo aims to enhance the receiver’s capabilities further and is also developing a transmitter for two-way communication. This task presents additional challenges due to the need for high current levels to generate the Wi-Fi signal, with previous attempts failing under radiation exposure. The team is exploring alternative materials, such as diamond, to improve the transmitter’s resilience.
This article was produced by NeonPulse.today using human and AI-assisted editorial processes, based on publicly available information. Content may be edited for clarity and style.
