Japan Accelerates Development of Over-the-Horizon Radar to Monitor Chinese Activities from Mainland

Policy for Practical Application After 2029

The Japanese government is promoting a plan to install an Over-the-Horizon (OTH) radar on an island in the western part of Okinawa Prefecture to strengthen surveillance of Chinese military activities. The OTH radar is equipment capable of detecting movements of objects beyond the horizon.

Yonaguni Island, Okinawa Prefecture, Japan. [Image source=Yonhap News]

According to the Yomiuri Shimbun on the 12th, Japan's Acquisition, Technology & Logistics Agency (ATLA) will accelerate research and development of OTH radar that can monitor activities beyond the horizon, which cannot be detected by existing radars. ATLA plans to start prototype production on Yonaguni-jima in Okinawa Prefecture by March next year at the earliest and aims to put it into practical use after 2029.

Yonaguni-jima is located about 110 km from Taiwan, and the distance to the Senkaku Islands (called Diaoyu Dao in Chinese), over which Japan and China have a territorial dispute, is about 150 km.

If the OTH radar is deployed on Yonaguni-jima, Yomiuri's analysis suggests that it will be possible to monitor vessels navigating around the Senkaku Islands from the ground. It also has the advantages of low operating costs and the ability to continuously monitor a wide area.

Yomiuri reported, "Since aircraft and satellites cannot always monitor all areas, it is necessary to combine various equipment to strengthen surveillance and monitoring posture," adding, "There is information that China has also installed OTH radar."