The tracking network system consists of earth stations with antennas and transmitters/receivers, the station control system that remotely surveys and controls the earth stations, the planning system that plans and manages the operation plans, and the backbone network that connects these systems and users. The role of the Backbone Network Maintenance Team is to maintain and control these systems so they work in harmony with the tracking controls. The tracking network must work perfectly 24 hours a day, 265 days a year to support the operation of satellites in each of their respective orbits. The team has the responsibility to live up to this standard.

The Technology Development Team performs R&D for every aspect of space tracking and controls, from antenna to network operations. In recent years there have been two significant developments: The “Ka” antenna that enabled high-speed data communications and the Misasa 54m antenna used for deep space exploration and more. The continued development and experimentation with DTN technology will help enhance the quality of communications and expand their functions. We have accumulated advanced technology and a lot of experience in the communication and data handling fields, and we will continue to meet the needs of more advanced space communications on a daily basis.

Space Debris is recognized as a major threat to the operation of spacecraft. The Orbit Team members receive and analyze data about space debris that poses a threat to a satellite from the US. If the collision risk is high, a change to the satellite’s orbit is suggested to the satellite manager. In recent years, avoiding space debris has become important enough to say it is a common feature of all satellite operations. In response to this, JAXA’s SSA equipment will be tested in FY2022. A more accurate risk assessment is now possible because data reinforcing the approach information of space debris can be obtained from the US. So, we believe that safe spacecraft operation and sustainable space development will be possible. The space debris collision avoidance support tool called “RABBIT” has been made available free of charge in Japan and for other countries. This raises the level of technology from JAXA, and their highly accurate risk assessments will be available even when an orbit specialist is unavailable. In addition, there is a small and modestly priced laser distance measurement reflector called “Mt. FUJI” that can be used universally, for any satellite or rocket in a low earth orbit. We have been recognized for this achievement globally.

The Katsuura Tracking and Communications Station, the Matsuda Tracking and Communications Station, and the Okinawa Tracking and Communications Station in the JAXA Tracking and Communications Center, are the facilities required for tracking and controls of satellites or spacecraft etc. Each of these Stations has two or more large parabolic antennas and they configure the earth network for JAXA’s tracking and control operations in the operation facilities. Our job is to manage these space communication facilities.
The Katsuura Tracking and Communications Station, the Matsuda Tracking and Communications Station, and the Okinawa Tracking and Communications Station, also do a lot of public relations and information dispatch activities for the general public, as part of JAXA’s operation facilities. The public relations exhibition facilities at each of these Tracking and Communications Stations, have the opportunity to conduct events, etc. in their local municipalities. They really make an effort to initiate projects to help people become more familiar with JAXA’s activities.

The Usuda Deep Space Center was constructed to transmit operational commands to deep-space probes that approach and observe astronomical bodies such as comets, planets and asteroids, and receive the observation data from the probes. This site was selected in order to receive the weak signals from probes in deep space. The distance is so immense that there needed to be very low radio wave interference and other such noise common to a city. This Center opened in October 1984. The large parabolic antenna at the core of the facility has a reflecting mirror with a diameter of 64m and the total weight is 2,000 tons. Communications with spacecraft are performed using band S (2GHz) and band X (8GHz). The US (NASA), Russia, ESA, CHINA and India own antennas designed for the same purpose. Previously, a parabolic antenna with a diameter of 10m was used to obtain the VLBI (Very Long Baseline Interferometry) observation data from the Radio Astronomical Satellite “HALCA” that orbits the earth. Now however, it is used for various experiments for VLBI or high-speed data transmission. An antenna with a diameter of 64m is used for spacecraft high precision orbit determination of using VLBI technology, and also high precision antenna position land survey and astronomical observation.

The GREAT-2 project has surpassed the GREAT project completed in May 2021. This will further enhance the reliability and operability of the Misasa Deep Space Station, and new functions to receive mission support from overseas organizations have been added. These new functions help promote the mutual cooperation and support of NASA and ESA, which has been encouraged for many years. More functions will be added to NASA’s “Nancy Grace Roman Space Telescope” or ESA’s “Hera”, etc.

JAXA formed the SSA (Space Situational Awareness) Project Team in 2016 to maintain the space debris observation system, as space debris is increasingly becoming a serious problem for space development. The SSA Project Team continually renews and improves its observation equipment to observe ever-smaller pieces of space debris. They are also developing a new and improved analysis system called “SAKURA”. Their works are now in the final stage, aiming to start operations in 2023.

The Planning Team’s jobs are roughly divided into three categories. The first is planning the tracking network operations for JAXA and budget management. The second is to promote cooperation with overseas space organizations and the development of discussion about technology to enhance the mutual operability of communication methods. The third is preparation, adjustment and operation planning for the tracking network with users in and out of JAXA. The main operations in the first category are operational promotion and adjustment. However, the main operations in the second and third categories are to propose new ways to solve issues in the present, or imagine future challenges. They must also provide a tracking network appropriate for users’ needs. So, the Planning Team can be thought of as a “coordinator”, whose job it is to come up with ideas regarding the future of space communications. They do this by meeting the needs of the related organizations and the people using the tracking network technology.