It was learned on Feb. 15 that the government has decided to set up a system with Vietnam, the Philippines, and Indonesia for monitoring radio jamming by China and North Korea. Japan will provide top-of-the-line Japanese-made shortwave monitoring devices to these countries to enable more accurate detection of the source of jamming signals. The plan is to start the operation of this joint project from FY20.
In light of the territorial disputes of Vietnam, the Philippines, and Indonesia with China in the South China Sea, radio systems of ships and aircraft passing through the South China Sea often suffer interference by beams from China which disrupt navigation.
Japanese ships have also suffered from jamming from China in the East China Sea, and the government has repeatedly asked the Chinese government to stop such action, since this may impede safe navigation. While jamming would be reduced after the requests were made, they have tended to resume after a while.
North Korea has also jammed the shortwave broadcast beamed at North Korea, Radio Shiokaze [Radio Sea-Breeze] operated by a Japanese private group, the Investigation Commission on Missing Japanese Probably Related to N. Korea (COMJAN), on some 50 occasions since 2009, particularly in March 2017.
In response to radio jamming by China and North Korea, the government has set up monitoring facilities to determine the source of signals in Aso (Kumamoto Prefecture), Ishigaki (Okinawa Prefecture), and three other locations nationwide. However, it is particularly difficult to track jamming signals beamed at the East China Sea and Japan’s southwest.
By operating a joint monitoring system with the governments of Vietnam, the Philippines, and Indonesia, “it will be possible to determine the source more accurately through joint investigations with the other countries,” according to a senior government official. If the source of jamming signals can be determined with accuracy, it would be possible to strongly demand that China refrain from jamming.