Researchers
研究者名
Harada, Hiroshi
研究者名
Reo Gakumi
Overview
A research group led by Professor Hiroshi Harada and doctoral student Reo Gakumi of the Graduate School of Informatics, Kyoto University has developed and demonstrated common firmware that enables two international wireless communication standards to operate concurrently using a single radio transceiver: Wi-SUN FAN, which is applicable to the outdoor-side communications between electric power smart meters and electric utilities (Route A), and Wi-SUN HAN, which is used for the in-home communications between smart meters and home energy management systems (HEMS) (Route B). The technology adds two new functions to the common firmware for both standards announced in May 2026: a “radio sharing arbiter” that allocates radio time between the two standards, and “fast PHY switching”, which switches the communication scheme in approximately 1 millisecond for a complete FAN-to-HAN-to-FAN switching cycle while maintaining the connection state of both standards.
Using a wireless module running the developed firmware, the group conducted demonstration experiments in two use cases involving smart meters and HEMS devices. In the smart meter application, the group confirmed that the module can both transmit meter-reading data to the electric utility via Wi-SUN FAN and respond to electricity usage data requests from HEMS devices via Wi-SUN HAN. In the HEMS device application, the module read electricity usage data from a smart meter via Wi-SUN HAN while connected to an independent IoT wireless network using Wi-SUN FAN, achieving a data delivery rate of 99.99% or higher on the Wi-SUN FAN side and an on-time response rate of 99.95% for power-value reads at 10-second intervals on the Wi-SUN HAN side. These results are expected to help reduce the cost and size of the wireless communication units in smart meters and HEMS devices, and are expected to find application not only in next-generation smart metering systems but also in joint metering of electricity, gas, and water utilizing electric power smart meter networks, as well as in wide-area energy management systems.
Key points
- Developed common firmware that operates Wi-SUN FAN and Wi-SUN HAN simultaneously on a single radio unit. Implemented a “radio sharing arbiter”, which coordinates the radio usage time of the two standards, and a “fast PHY switching” function, which switches the communication scheme in approximately 1 millisecond per complete switching cycle while maintaining the connection state of both standards.
- In a demonstration of the smart-meter use case, confirmed that a single radio unit can both transmit meter-reading data to the electric utility via Wi-SUN FAN and respond to power-value read requests from HEMS devices via Wi-SUN HAN.
- In a demonstration of the HEMS use case, achieved both the reading of electricity usage data from a smart meter via Wi-SUN HAN and connection to an independent IoT wireless network using Wi-SUN FAN. Confirmed a data delivery rate of 99.99% or higher on the Wi-SUN FAN side and an on-time response rate of 99.95% on the Wi-SUN HAN side.
