Fukushima Robots Shed Their Cables After Decade of Wired Restriction

Inside the Fukushima Daiichi Nuclear Power Plant, the robots move carefully through corridors where no human should go. They crawl through rubble, photograph fuel debris, and map contamination — and for the past decade they have done most of it trailing cables behind them like umbilical cords. That may be changing.

Researchers at the Institute of Science Tokyo (Science Tokyo) — a university formed in 2024 from the merger of Tokyo Institute of Technology and Tokyo Medical and Dental University — have developed a 2.4 GHz Wi-Fi receiver chip that survives a cumulative radiation dose of 500 kilograys (kGy) a TechXplore report. That number matters because it puts wireless communication within reach of environments that would fry conventional electronics almost instantly. The chip was presented at the 2026 IEEE International Solid-State Circuits Conference (ISSCC) in San Francisco in February.

The lead researchers are graduate student Yasuto Narukiyo and Associate Professor Atsushi Shirane of Science Tokyos Institute of Innovative Research, in collaboration with Associate Professor Masaya Miyahara at the High Energy Accelerator Research Organization (KEK) in Japan.

"Such tolerance addresses the requirements of nuclear power plant decommissioning, which involves exposure to intense gamma radiation emitted from fuel debris," Shirane said in the EurekAlert press release. "Introducing such a wireless system eliminates the need for complex cabling and enables efficient and seamless operation of a large number of robots."

The scale of the problem theyre solving is large. According to the International Atomic Energy Agency (IAEA), nearly half of the 423 nuclear power reactors currently in operation worldwide are expected to enter decommissioning by 2050. Fukushima became the proving ground for remote-controlled nuclear robotics after the 2011 disaster, and what became clear there is that the cables are a real constraint — they limit how many robots you can run at once, create chaos in confined spaces, and slow operations down in ways that translate to extended human exposure and higher costs.

An AAAS Science report found that the cables are a real constraint — they limit how many robots you can run at once, create chaos in confined spaces, and slow operations down in ways that translate to extended human exposure and higher costs.

The standard approach to making chips radiation-hardened usually involves expensive specialized fabrication processes or physical shielding. The Science Tokyo team took a different route: they redesigned the chips circuit architecture to reduce its vulnerability in the first place. The key moves were removing transistors where possible and replacing them with passive inductors. Transistors trap charge when hit with gamma radiation, causing electrical leakage and signal degradation. Inductors dont. In both the variable-gain amplifier and the RF amplifier stages of the receiver, radiation-sensitive transistors were swapped out for inductors. The remaining transistors were made physically larger — bigger devices are less affected by edge-related leakage that radiation tends to create.

The results after 500 kGy of cumulative gamma exposure: signal gain dropped by only 1.4 decibels, noise figure increased by at most 1.26 decibels, and power consumption actually decreased slightly by about 2 milliwatts. By those numbers, the chips communication performance stayed comparable to standard commercial Wi-Fi receivers. Thats the point — not just surviving radiation, but surviving it without becoming useless.

"By realizing Wi-Fi chips that operate stably even under ultra-high-dose radiation environments, wireless remote operation using robots and drones will be promoted, enabling reductions in worker radiation exposure risk and advances in work sophistication," Shirane said.

The human angle here is direct. Decommissioning a nuclear plant takes more than 20 years on average. Workers have to be rotated to manage cumulative radiation dose — time near the contaminated core is rationed. Every hour a robot can operate autonomously and wirelessly, covering more ground without a handler dragging cable, is an hour fewer humans spend at elevated risk. Multiply that across a decommissioning pipeline that is about to scale dramatically.

The chip also has a secondary application the team flagged: the radiation tolerance is actually higher than what electronics typically face in space. That makes it potentially useful for deep-space missions and satellite systems — a market already interested in radiation-hardened RF components, as Science Tokyos own prior work on Ka-band satellite chips demonstrates.

The paper is titled "A 500kGy Radiation-Hardened 2.4GHz Wi-Fi Receiver for Innovative Nuclear Power Plant Decommissioning" and was published February 19, 2026 at ISSCC. The next step is getting a chip like this into an actual decommissioning robot — a jump from chip demo to field deployment that involves qualification testing, system integration, and the institutional caution of nuclear operators. That gap is real, and it can take years. But the foundational spec — 500 kGy, standard Wi-Fi band, comparable performance to commercial receivers — makes the engineering path look credible in a way earlier radiation-hardened designs did not.