Usuda Deep Space Center
Coordinates: 36 ° 7 ′ 59 ″ N , 138 ° 21 ′ 44 ″ E
The Usuda Deep Space Center (UDSC, Japanese 臼 田 宇宙空間 観 測 所 , Usuda Uchū Kūkan Kansokujo , German "Usuda Space Observatory") is a facility of the Japan Aerospace Exploration Agency (JAXA) near Usuda , in Nagano Prefecture , Japan . Usuda is now part of the city of Saku .
General
The station went into operation in 1984 and has two antennas, a third has been under construction since 2016. The facility is located far away from transmitter masts, flight routes, settlements and traffic arteries at an altitude of 1456 meters above sea level and the location is chosen so that the surrounding mountains shield off unwanted radio signals. The facility is temporarily open to the public. A visitor reception building with a small exhibition belongs to the site. Along the approach there is a small planetary path on a scale of 1: 5.5 billion, which, however, for reasons of space only extends from the sun to Jupiter. There are also buildings for administration and data processing. All systems comply with the provisions of the CCSDS , so data exchange and cooperation with the antenna networks of other space agencies is possible.
64 meter main antenna
The main antenna is a 64 meter antenna weighing 2000 tons. The antenna is equipped for communication in the S band (approx. 2–4 GHz) and in the X band (approx. 8–12 GHz). Usuda large antenna was the first large Cassegrain beam wave guide antenna ever built. With these antennas, the received signals are directed via the secondary mirror and a hole in the primary mirror via various reflectors into the substructure of the antenna, where the corresponding receivers and transmitters are kept ready. The receivers and transmitters are protected from the weather and unwanted radiation, can be cooled better and are more easily accessible and can be serviced or replaced without the use of a crane. The construction of the movable bowl is relieved of the weight of the transmitter and receiver. This technology was revolutionary at the time and brought an improved noise level compared to the 64-meter antennas of NASA's own Deep Space Network (DSN) and easier handling. Newer antennas are mainly built according to this principle.
In view of the ongoing space missions, the antenna is to be expanded with an additional receiver in the Ka-band.
10 meter antenna
For Very Long Baseline Interferometry (VLBI) there is a 10-meter antenna that is set up a little apart.
54 meter antenna (GREAT)
This antenna, named Ground Station for Deep Space Exploration and Telecommunication (GREAT) and a diameter of 54 meters, has been under construction since 2016. The main mirror was installed towards the end of 2018, and the technology has been installed and tested since then. It is scheduled to go into full operation in April 2021. 36 ° 8 '27.1 " N , 138 ° 21' 7.8" E
The location at an altitude of 1580 m is 1.3 km away from the previous antenna in order to prevent unwanted interference. It should take over the tasks of the 65-meter antenna, which is now over 30 years old and has already exceeded its planned service life by more than ten years. Despite its smaller diameter, the new antenna should be on a par with the older antenna in terms of performance. It is designed in such a way that solar radiation, snowfall, rain and wind loads only have a minimal effect on its function. A particularly precisely shaped antenna dish and stronger directional effect, as well as more precise alignment and state-of-the-art receivers should compensate for the smaller diameter. With a deviation from the ideal shape of only about 0.6 mm maximum, the value of the old antenna is clearly undercut with deviations of up to 5 mm.
Technical specifications:
Cassegrain antenna with adaptive surface adaptation, weight 2200 t
Frequencies:
- X-band transmission for tracking and controlling spacecraft (7145 MHz to 7235 MHz)
- X-band reception (8400 MHz to 8500 MHz)
- Ka-band reception (31800 MHz to 32300 MHz)
- X-band reception for VLBI (8200 MHz to 8700 MHz)
X-band transmission gain: 69.62 dBi or more
X-band transmit power: 20 kW or more ( EIRP 142.5 dBm or more)
Received power:
- X-band G / T: 53.35 dB / K or more at an elevation angle of 15 ° to 80 °
- Ka-band G / T: 59.33 dB / K or more at an elevation angle of 15 ° to 80 °
The new antenna will play an important role in the BepiColombo mission jointly undertaken by ESA and JAXA . Both Usuda and the ESTRACK network are preparing antennas for this mission to receive large amounts of data in the Ka-band . Upon arrival, the MMO magnetospheric orbiter MIO will communicate with Usuda, while ESOC will focus on the Mercury Planetary Orbiter. The majority of the probe data should be sent via the Ka-band.
Supported missions
All stations comply with the provisions of the CCSDS , so data exchange with the systems of other space agencies is possible despite different technical equipment. Usuda's 64-meter antenna was part of the Voyager 2 mission . The reception capacities of the antennas of NASA's Deep Space Network were not sufficient to receive the data during the encounter with Neptune . In addition to the DSN, the 27 25-meter antennas of the Very Large Array of the National Radio Astronomy Observatory in New Mexico, the 64-meter antenna of the Parkes Observatory in Australia and the 64-meter antenna in Usuda were used.
Support was given to Japan's first interplanetary space probes Sakigake and Suisei , the lunar orbiter Kaguya , the asteroid probe Hayabusa and the Venus probe Akatsuki . Usuda played a significant role when communication with Hayabusa was temporarily lost.
Supports will Hayabusa 2 . Communication in the Ka-band has been done via the DSN since the beginning, but is to take place from Usuda after GREAT is put into operation.
Other antenna systems
In the event of an emergency, the 20-meter and the powerful 34-meter parabolic antenna of the Uchinoura Space Center can serve as a backup in the S and X bands. The Katsuura Tracking and Communications Station is equipped for satellite tracking with four parabolic antennas with diameters of 20 meters, 13 meters, 11 meters and 10 meters. The Okinawa Tracking and Communications Station is also used for satellite tracking. For tracking there is an 18-meter and a 10-meter antenna, as well as a 30-meter antenna. Two 7.5-meter bowls are each in a radome . JAXA also operates four tracking stations outside of Japan in Kiruna (Sweden), Santiago (Chile), Mingenew (Australia) and Maspalomas (Canary Islands).
literature
- JP Goodwin: Usuda Deep Space Support for ICE , TDA Progress Report 42-84, pp. 186-196, October-December 1995.
- JAXA (Ed.): GREAT ： GRound station for deep space Exploration And Telecommunication . ( jaxa.jp [PDF]). , with no publication date.
Individual evidence
- ↑ Usuda Deep Space Center. JAXA, Japan Aerospace Exploration Agency, accessed August 26, 2017 .
- ↑ D. Neff: Use of a 2.3 Ghz Traveling-Wave Maser on the Usuda 64-Meter Antenna. March 1987, accessed August 26, 2017 .
- ↑ Usuda Deep Space Center. ISAS, Institute of Space and Astronautical Science, accessed on August 26, 2017 .
- ↑ JAXA | GREAT, Ground Station for Deep Space Exploration and Telecommunication . In: JAXA | Japan Aerospace Exploration Agency . ( jaxa.jp [accessed August 30, 2017]).
- ↑ Kenji Numata: Toward a New Era of Deep Space Exploration Kenji Numata Project Manager, Ground Station for Deep Space Exploration and Telecommunication Project . Ed .: JAXA. ( jaxa.jp [accessed August 30, 2017]).
- ↑ GREAT の 概要 - 深 宇宙 探査 用地 上 局 プ ロ ジ ェ ク ト. Retrieved June 13, 2020 .
- ↑ Usuda Deep Space Center Joins Voyager 2 Mission. Retrieved August 26, 2017 .