DSN的介绍
Every U.S. deep space mission is designed to allow continuous radio communication with the spacecraft. Continuous 24-hour coverage for several spacecraft requires several Earth-based stations at locations that compensate for the Earth's daily rotation. The locations in Spain, Australia, and California are approximately 120 degrees apart in longitude, which enables continuous observation and suitable overlap for transferring the spacecraft radio link from one complex to the next.
The Australian complex is located 40 kilometers (25 miles) southwest of Canberra near the Tidbinbilla Nature Reserve. The Spanish complex is located 60 kilometers (37 miles) west of Madrid at Robledo de Chavela. The Goldstone complex is located on the U.S. Army's Fort Irwin Military Reservation, approximately 72 kilometers (45 miles) northeast of the desert city of Barstow. Each complex is situated in semi-mountainous, bowl-shaped terrain to shield against radio frequency interference.
Each complex consists of at least four deep space stations equipped with ultrasensitive receiving systems and large parabolic dish antennas. There are:
One 34-meter (111-foot) diameter High Efficiency antenna.
One 34-meter Beam Waveguide antenna.
(Three at the Goldstone Complex)
One 26-meter (85-foot) antenna.
One 70-meter (230-foot) antenna.
Five new 34-meter beam waveguide antennas were added to the system in the late 1990's. Three were located at Goldstone, and one each in both Canberra and Madrid. To support the growing demands on the DSN, another antenna is currently under construction at the Madrid site.
The ability to array several antennas was installed to improve the data returned from the Galileo spacecraft. The array electronically links the 70-meter antenna at the Deep Space Network complex in Goldstone, CA, with an identical antenna located in Australia, in addition to two 34-meter (111-foot) antennas at the Canberra complex. The California and Australia sites concurrently pick up communications with Galileo.
All the stations are remotely operated from a centralized Signal Processing Center at each complex. The Centers house the electronic subsystems that point and control the antennas, receive and process the telemetry data, transmit commands, and generate the spacecraft navigation data.
Once the data is processed at the complexes, it is transmitted to JPL for further processing and distribution to science teams over a modern ground communications network.
都是用于与空间飞船联系的射电天线
