ESTRACK tracking stations
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The ESA tracking stations network - ESTRACK - is a worldwide system of ground stations providing links between satellites in orbit and our Operations Control Centre at ESOC. The core ESTRACK network comprises 13 terminals sited at nine stations in six countries.
The essential task of all ESA tracking stations is to communicate with our missions, up-linking commands and down-linking scientific data and spacecraft status information. ESTRACK stations also gather radiometric data to help mission controllers know the location, trajectory and velocity of their spacecraft.
ESTRACK stations provide additional services, including searching for and acquiring newly launched spacecraft, auto-tracking, frequency and timing control using atomic clocks and gathering atmospheric and weather data. Some stations are also equipped with GPS receivers connected to our GPS Tracking and Data Analysis Facility at ESOC, enabling highly precise orbit and geophysical calculations.
Each ESTRACK station hosts one or more terminals, each of which comprises an antenna and its associated signal processing equipment. Stations can support multiple missions and ESTRACK also shares resources with other agencies and satellite operators.
ESTRACK Core Network
The Core Network comprises nine ESTRACK stations: Kourou (French Guiana), Maspalomas, Villafranca and Cebreros (Spain), Redu (Belgium), Santa Maria (Portugal), Kiruna (Sweden) and Perth and New Norcia (Australia).
ESTRACK station locations During routine operations, stations are remotely operated from the ESTRACK Control Centre (ECC) at ESOC.
ESTRACK technology
All stations host 13-, 13.5- or 15-metre antennas, except New Norcia and Cebreros, equipped with new 35-metre deep-space antennas, and Santa Maria, with a 5.5m antenna. Older stations communicate using a mix of S-, Ka- and X-Bands (2025-2300 MHz, 18.1-32.3 GHz, 7145-8500 MHz, respectively), while the two new 35m DSA stations primarily use the newer X-band.
Data rates vary greatly depending on the mission, direction (up-link or downlink) and other factors, but typically range from 256 Kbit/s (kilobits per second) to 8 Mbit/s (megabits per second).
Six ESTRACK stations are equipped with GPS (global positioning satellite) receivers and are connected to ESA's sophisticated GPS-based Tracking & Data Analysis Facility, while the two deep-space stations are equipped with extremely accurate delta-DOR (delta-Differential One-way Range) spacecraft tracking technology.
Santa Maria joined ESTRACK in January 2008 to track launches from ESA's Spaceport in Kourou, initially supporting the ATV launch on Ariane 5.
The ESTRACK Core Network typically provides over 44 000 hours of tracking support each year, and enjoys an enviable 99-percent availability rate.
 | | | New Norcia: DSA 1 |
ESA Deep Space Network
ESTRACK's new 35m stations at New Norcia (Deep Space Antenna - DSA 1) and Cebreros (DSA 2) form the European Deep Space Network.
The new stations provide the improved range, radio technology and data rates required by current and next-generation exploratory missions such as Mars Express, Venus Express, Rosetta and BepiColombo.
| | | Cebreros: DSA 2 |
Deep-space missions typically orbit more than 2 million kilometres from the Earth, and communicating at such distances requires highly accurate mechanical pointing and calibration systems.
DSA 1 and 2 also have facilities for radio science experiments, allowing scientists to study the characteristics of matter through which the spacecraft-ground communication signals travel.
New Norcia was completed in November 2002; Cebreros was completed in September 2005. These will be complemented with a third station to be built in the 2010-11 time-frame at an American longitude, possibly in South America.
ESTRACK Augmented Network
The ESTRACK system also includes terminals operated by external organisations on ESA's behalf:
- MAL-1 in Malindi (Kenya)
- SG-3 in Svalbard (Norway)
- AGO-1 in Santiago (Chile)
These provide additional support for certain missions (typically, XMM-Newton, Envisat, ERS-2), during routine operations, as well as during LEOP.
Additional stations are used in some cases, including Alaska (ASK), Dongara (DON) and Weilheim (WHM-1/9; used most recently for SMART-1).
ESTRACK Cooperative Network
Additional ESTRACK Cooperative Network stations are provided on a resource-sharing basis by other organisations, including CNES (France), DLR (Germany), NASA's Deep Space Network and Goddard Space Flight Centre and JAXA (Japan).
These stations have supported Mars Express, Integral, Venus Express and Rosetta, among many others.
| | | NASA deep-space station Canberra |
This global network allows ESA missions to make use of a wide number of ground terminals in geographically advantageous locations, mainly during LEOP or other critical mission phases.
Conversely, ESTRACK resources are also shared with other agencies to maximise efficiency and enhance scientific returns.
For example, ESA presently has specific Memorandum of Understanding (MOU) agreements in place for NASA Deep Space Network (DSN) support to Mars Express, Venus Express and Rosetta.
EU, International regulations and standards
ESTRACK terminals operate in the ITU (International Telecommunications Union) frequency bands allocated to the "space science services" and to the "fixed-satellite service" in the case of Artemis - ESA's telecommunications satellite - supported from Redu.
| | | Use of radio frequencies is regulated by the ITU |
In accordance with ITU radio regulations and agreements between ESA and the station host countries, ESTRACK terminals respect the requirements on minimum elevation angle and maximum power radiated toward the Earth surface, as well as any site-specific constraints included in these agreements.
Individual frequency licenses are obtained for any missions to be supported by ESTRACK. ESTRACK stations are designed in accordance with the European Cooperation for Space Standardisation (ECSS) standards.
Typical ESTRACK station technical profile
The table below provides the technical profile of a typical ESA S- or X-band ground station. Note for comparison that a typical 'high-speed' home DSL Internet connection in Western Europe provides a download data rate of 1.5-5 mbps.
| Characteristic | Typical range |
| Antenna dish diameter | 15m, 35m |
| Transmit frequency |
| S-band | 2025-2120 MHz |
| X-band | 7145-7235 MHz |
| Receive frequency |
| S-band | 2200-2300 MHz |
| X-band | 8400-8500 MHz |
| Telemetry (downlink) |
| Normal data rate | up to 1 Mbps |
| Maximum data rate | up to 105 Mbps |
| Telecommand (up-link) |
| Normal data rate | 2 Kbps |
| Tracking |
| Range accuracy | 1 m |
| Range rate accuracy | 0.1 mm/s |
Last update: 21 January 2008 | 
Tracking station videos
