“In Japan, navigation technology is now mainly based on satellite positioning technology”

Kiyokazu Minami and Takeyasu Sakai of Japan Institute of Navigation discuss the scenario of navigation technologies in Japan in an interview with Coordinates magazine

Kiyokazu Minami Secretary General, Executive Director, Japan Institute of Navigation

Takeyasu Sakai Member, Leader of GPS/GNSS research group, Japan Institute of Navigation

What are the objectives of the Japan Institute of Navigation (JIN)? Would you like to highlight some recent activities and the achievements of the JIN?

The purpose of JAPAN Institute of Navigation (JIN) is to contribute to the development our country and to improve the lives of our people by considering and improving the science of navigation. JIN was established in1948. Its research fields include not only technologies for the safe navigation technologies but also more recently research into satellite navigation technologies, both at sea and on land, and ocean development technologies, including topics that are currently attraction a lot of attention. In 2018, JIN managed the 16th word congress of the International Association of Institutes of Navigation (IAIN) in Makuhari, Chiba, JAPAN, which brought together much research in the field of navigation from around the world. In Asia, JIN also organizes the Asia Navigation Conference (ANC) every year in cooperation with navigation-related societies in China and Korea, where research results that contribute to the development of maritime technology are presented.

What is the general scenario of navigation technology in terms of status, trends and challenges in Japan?

In Japan, navigation technology is now mainly based on satellite positioning technology, which is now widely used for land and sea operations. Japan has planned a navigation satellite system called the Quasi-Zenith Satellite System (QZSS), which has been in operation since 2017; the satellite MICHIBIKI has been launched since 2010 and the system currently consists of a total of four satellites. With this system, Japan is using GNSS and QZSS launched abroad to develop technologies using various satellite positioning systems. Navigation uses these satellite-positioning systems to control active land-based vehicles (cars and agricultural equipment). Automobiles are in operation on the condition that vehicles that can be driven automatically are allowed to navigate on public roads and that the steering lab is immediately transferred to the driver. On the other hand, for ships, demonstrative tests of automation have been repeated on domestic vessels navigating regular routes, and tests have been carried out on cargo ships and ferries, where automated navigation has been achieved without incident. Challenges include improving safety and reliability. In addition, it is necessary to develop technologies to ensure these, reduce costs, operate efficiently, and reduce the environmental impact. Navigation plays a major role in improving safety, and in particular the development of technology to safely control moving vehicles needs to be identified and implemented as soon as possible.

What is the update on the MTSAT Satellite Augmentation System (MSAS)?

MSAS is now version 2. The old MSAS, sometimes called MSAS V1, terminated its operation by the end of March 2020. The current MSAS, MSAS V2, has been in operation since the beginning of April 2020. MSAS V2 has fully new facilities, including a geostationary satellite QZS- 3, modern master station with a backup, and 13 ground monitor stations.

What is the status of Quasi-Zenith Satellite System (QZSS)?

Now we have a new satellite QZS-1R which is the replacement of QZS- 1 launched in 2010. By the end of year 2024, we will have three additional satellites, QZS-5, -6, and -7, to complete the QZSS 7-satellite constellation.

What are key application areas emerging in Japan in positioning and navigation technologies?

Recently location-based services using smart phone seems quite attractive. Also, they are trying application of drone or UAV in various fields.

What are focus areas of research in general in academia in positioning and navigation technology?

It might be signal processing by SDR including application to positioning using LEO satellites.

This is a world of mult-GNSS systems. What advantages do you see about this scenario?

It solves the problem due to the number of satellites in urban applications.

With increasing dependence on GNSS, how do you perceive the threats like interference, jamming and spoofing?

In Japan, attacks to satellite navigation systems are not reported yet. Perhaps they have some doubt about such threats; Is it really possible to spoof GPS for mobile users? Of course, technically the answer is yes, but we need to consider cost-benefit balance.

How do you think the GNSS positioning technology can take the advantages of other positioning technologies cell phones, Bluetooth and WiFi, etc?

GNSS positioning is well-defined, easy-to-use positioning means. GPS-specialized chips is available and cheap, and popular than other means.

What influences you envisage in satellite navigation in the near future given the advancements in the field of AI, Autonomous Vehicles, etc.?

Safety is the most important function of positioning systems. The provider of Autonomous Vehicles will use the GNSS as long as it has some precise position (approx. 10cm-level). So the question is how reliable and available position GNSS can provide. AI technology will also be used in the field of GNSS.