"Multipurpose Deep Space Radio Tracking Station (URSA)"
Project title Multipurpose Deep Space Radio Tracking Station (URSA) Key words: Space, surveillance, sensor, satellite, radio Project summary Space surveillance provides information on what is orbiting Earth. Space surveillance networks are mostly based on electro-optical and radar sensors. However, the existing networks of sensors have limited capacity and coverage, especially for deep-space tracking applications. Another problem is that radar and electro-optical sensors cannot provide all needed information regarding a space object (the satellite status can be active or not, for instance). It is why the monitoring of radio broadcasts is required to accomplish the full operational picture of artificial satellites. This task can be accomplished including passive radio sensors in space surveillance networks. The main purpose of the URSA project is to develop Romanian scientific capabilities and to join ongoing European initiatives in the field of Space Surveillance. The project will explore the deployment of electro-optical and radio ground-based passive orbital activity surveillance sensors and the development of connected applications in the field of space and security research. The project objectives are: 1. Setup of an integrated electro-optical and radio space surveillance system 2. System validation 3. Explore the scientific applications of URSA. This deep space surveillance system can provide information concerning the main characteristics of satellites or any other space object (e.g. orbital parameters, transponders activity, and broadcasts analysis). It can also give support to small scientific satellite missions, providing tracking services. Another important output of the project is a package of applications supported by URSA, in the field of radioastronomy and space communication experiments, and targeting (especially) the Romanian scientific community, since no such facility is available at national level. Relevance of the project URSA is the first Romanian facility for space surveillance experiments, fully designed and deployed by a multi-disciplinary Romanian team of researchers. It’s electro-optical and radio tracking capabilities can contribute to national or international space & security research projects (for instance, URSA can give support to future scientific satellite missions - such as the Romanian nanosatelites for space exploration). Other applications supported by URSA and targeting the Romanian scientific community are radioastronomy and space radio communication experiments. URSA can also provide information concerning the main characteristics of satellites (e.g. orbital parameters, transponders and activity status, broadcasts analysis) for security applications. Project description 1. S/T current stage in the field The combined tasks of the detection, characterization, correlation, and orbit determination of space objects describe the scope of ”space object surveillance”. Most of the data on space objects is collected by the United States Space Command (USSPACECOM) using its Space Surveillance Network. This network of electro-optical sensors (also known as the URSA Project Ground-Based Electro-Optical Deep Space Surveillance system or GEODSS) and radar sensors detects, tracks, and identifies Earth orbiting objects, which are maintained in a space objects catalogue, and published in different formats. Electro-optical and radar sensors have something in common: all of them detect an (optical or radio) signal emitted by some external source and reflected by the satellite. Radars are primarily used for LEO, and optical systems are used for GEO surveillance and tracking. Apart from the US (supported by their SSN), Russia has a significant operational capability (supported by their Space Surveillance System, SSS). Also France has an experimental surveillance system, the bi-static GRAVES installation. The related catalogue is limited to objects of typically 1 m size and larger, in low Earth orbits (LEO). Apart from sensors which are involved in routine space surveillance (SSN and SSS), there are also sensors which track known objects with higher accuracy (e.g. FGAN/TIRA and Monge/ARMOR), and sensors which acquire more detailed statistical information on small-size objects (e.g. EISCAT). However, the existing network of ground sensors has limited capacity and coverage for deep-space tracking, and this is especially true for the eastern hemisphere of the geosynchronous belt. During the past decade, European research and development related to space surveillance has made significant progress. The existing experimental and operational radar and optical sensors, in conjunction with corresponding hard- and software for measurement data processing, have demonstrated their suitability as corner stones, or at least as stepping stones for future developments of a coordinated European space surveillance program. By the end of 2005, NATO RTO Space Science and Technology Advisory Group (SSTAG) included Space Objects Surveillance among its recommendations for (international) collaborative research. Several Romanian organizations have scientific knowledge in technologies involved in the deployment of space surveillance systems: ⇒ Optical tracking of low orbit satellites (Astronomical Observatories) ⇒ Radio communication technologies and radio-wave propagation (Universities) ⇒ Operation of low and medium-range military radars (Ministry of Defense) ⇒ Satellite communications (especially private companies). The Romanian Aerospace and Security programs supported in 2005 and 2006 a couple of preparatory projects which explored geostationary satellite detection techniques and their applications in space surveillance. 2. Contribution of the project to the development of the knowledge in the specific field Satellites (as well as any other active artificial space object) do not only reflect optical and radio signals, they are radio sources as well. All satellites, telecommunication, surveillance, GPS, etc., with orbits ranging from low to high altitudes, have something in common: each satellite uses at least one transponder that provides the connection between the satellite and some Earth station. Radar and electro-optical sensors can detect and track space objects but cannot provide too much information regarding the satellite’s (or other artificial space object’s) mission and status (active or not). It is why, the monitoring and analysis of space object broadcasts is required to accomplish its full operational picture. URSA is a complex system which integrates: passive electro-optical and radio sensors, orbital tracking and space radio communication technologies. The setup and deployment of URSA requires a wide range of expertise: astronomy and space geodesy, electro-optical systems, radio communications, satellite tracking technologies, electronics, software. URSA Project URSA is certainly the first such facility in Romania and among the very few (more or less) similar deployed in Europe. 3. General and specific objectives of the project The general objective of the URSA project is to setup and explore the scientific applications of an integrated electro-optical and radio space surveillance system. URSA range for electro-optical and radio surveillance of satellites covers the belts between LEO – GEO - HEO orbits. LEFT. The average altitude boundaries for the GEO satellites is actually a very thin belt, determined by the ideal orbit altitude such that the satellites will orbit the Earth in exactly one sidereal day. At 35,850 kilometres ideally. GEO satellites reside in the belt depicted in the figure, and orbit within Earth's equatorial plane. RIGHT. Average altitude boundaries for HEO satellites. The red boundary denotes the lowest average altitude. The blue boundary denotes the highest average altitude. This figure does not imply that HEO satellites can only reside within these boundaries. Their orbit semi-major axes do reside here. The highest boundary is actually the Moon's average altitude of 400,000 kilometres. The project has three specific objectives: Setup of an integrated electro-optical and radio space surveillance system System validation Explore the scientific applications of URSA The first objective will focus on system requirements and architecture, existing technology overview, electro-optical and radio sub-systems setup and test, system integration. The second objective concerns system deployment and tests. The third objective will explore the main applications supported by URSA (in the field of space surveillance, space communication experiments and radioastronomy) and will develop a package of applications for other interested organizations. 4. Detection methods and system components description The system uses passive optical and RF sensors that can detect and track space object’s electromagnetic emissions (such as the reflected Sun light or transponder radio emissions). 4.1 The electro-optical sub-system The electro-optical sub-system scans sky areas in order to detect and acquire information concerning space object orbital parameters. These data are important as input for the radio sensor tracking sub- system for the following reasons: 1. The orbital position of an unregistered satellite is not available. In such cases, the tracking system cannot rely on NORAD TLE or other similar data. 2. Having direct visibility to a satellite does not necessarily involve that its transponders are inside URSA Project the RF sensor field of view. 3. The radio sensor might not cover the frequencies of the satellite transponder. URSA detects space object’s electromagnetic emissions There are, as well, cases in which the radio sensor detects a transponder but the electro-optical sub- system fails in detecting the satellite (for instance, nights around full Moon). It is why these two sub- systems are complementary and should work together. The main electro-optical sub-system components are: 1. An az-el mount telescope (40 cm mirror recommended) with automatic search and track capabilities 2. The az-el mount command block 3. A high performance CCD camera 4. Data recording and processing block. Optical detection of geostationary satellites experiment at the Astronomical Observatory Feleacu (left) and geostationary satellites photo (right). The points are satellites and the lines are stars. URSA preparatory action, end of 2006. 4.2 The radio sub-system The radio sub-system scans sky areas around orbital positions where a satellite might be found. Orbital data are provided by third sources (such as NORAD TLE) for registered satellites or by the optical sub- system. A step track algorithm can be used as well to scan orbital positions for satellites with unknown orbital parameters and which cannot be observed by optical means. After a satellite has been detected, the radio sub-system scans the satellite transponders that are within its FOV. A minimal configuration for the radio sub-system is: 1. An az-el mount broadband antenna (type, frequencies and size/midband gain depending on applications) 2. The az-el mount command block for automatic search and track URSA Project 3. Low-band amplifier and spectral analyzer 4. Digital data processing block. In order to increase the signal-to-noise ratio and the capacity to detect far (low elevation) satellites, URSA is planned to be installed at high altitude. In fact, the project consortium already has two available testbeds for space surveillance experiments. Setup of a 3.8 m high gain C/Ku-band motorized antenna for radio detection of inclined orbit satellites at GEO altitudes. URSA preparatory action, BITNET CCSS, end of 2006. 4.3 URSA system architecture 5. Work plan, role and responsibilities of each partner per activity WP No. Activity No. Partners Responsibilities WP1 1.1 System requirements analysis and design; project presentation 1.1.1 UTCN, BITNET System requirements analysis 1.1.2 UTCN, BITNET System architecture design 1.1.3 UTCN, BITNET Web site 1.2 Electro-optical and radio tracking sub-systems setup 1.2.1 Experimental GEO/HEO electro-optical tracking sub-system setup 220.127.116.11 OA Automatic tracking block setup 18.104.22.168 OA Electro-optical block setup 1.2.2 Experimental GEO/HEO radio tracking sub-system setup 22.214.171.124 BITNET Automatic tracking block setup 126.96.36.199 BITNET, UTCN Radio block setup 1.2.3 Experimental LEO electro-optical tracking sub-system setup 188.8.131.52 OA Automatic tracking block setup 184.108.40.206 OA Electro-optical block setup 1.2.4 Experimental LEO radio tracking sub-sytem setup 220.127.116.11 BITNET, ASR Automatic tracking block setup 18.104.22.168 UTCN, ASR Radio block setup 1.2.5 URSA telecom infrastructure setup URSA Project BITNET Telecom infrastructure setup 1.3 System integration BITNET, OA Sub-systems integration and preliminary tests WP 2 2.1 System deployment 2.1.1 OA Electro-optical sub-system installation in the field 2.1.2 BITNET Radio sub-systems installation in the field 2.2 Operation tests and performance analysis 2.2.1 OA Optical tracking of LEO & GEO satellites 2.2.2 BITNET, UTCN, ASR Radio tracking and broadcasts analysis of LEO & GEO sat. WP 3 3.1 Scientific applications 3.1.1 BITNET, OA, ASR Space surveillance experiments and applications development 3.1.2 UTCN, BITNET Space com. experiments and applications development 3.1.3 OA, UTCN Radioastronomy experiments and applications development 3.2 UTCN, BITNET, URSA exploitation plan ASR, OA 3.3 BITNET, OA Public demonstration UTCN, ASR Promotion PROJECT CALENDAR R1 R2 R3 R4 R5 Project impact Security related impact It is important to point out that Romania is completely dependent on space object, mission and orbit information provided by international organizations. For instance, Romania is not able to detect a reconnaissance satellite that surveys its territory. This serious capability gap may be reduced, and ultimately resolved, with the installation of a (future) operational facility and the participation to the European Space Surveillance network. URSA is the first pre-operational space surveillance system developed by Romanian organizations. The main security applications of such a system are: ⇒ monitor the satellites on which relay the national communication and information network ⇒ track reconnaissance satellites ⇒ verify the application of international treaties in outer space ⇒ strategic evaluation of technological and operational capabilities of other countries/organizations; ⇒ provide decision makers with pertinent information regarding the situation in space within the decision process or the planning/conducting of operations. Scientific and technological impact URSA Project The project gives an opportunity for national and international expertise exchange, know-how, organizational and human resources development in the field of space surveillance technologies and their applications, in order to join existing European programs and further develop them. Social impact The project gives an opportunity to several young researchers to specialize in space applications related technologies. Description of the consortium UTCN – The Technical University of Cluj-Napoca / Department of Telecommunications has a long experience in research, education and participation to EU projects. It brings to the consortium its scientific competences in radio communication technologies. It is responsible for the project co-ordination, it will document radio communication technologies and will take part to the radio surveillance system setup, validation and scientific applications development. UTCN is member of the Integral SatCom Initiative and eMobility platforms. During last 15 years through the Radio Communications Group of the Telecommunications Department, UTCN coordinated or participated as partner to more then 30 research projects at national and international level. BITNET Research Center on Sensors & Systems Ltd. is a 14 years old private technological research company. International experience in space technology applications projects and satellite telecommunication services provider. Main responsibility within the project: provide and deploy satellite technology, radio tracking systems setup and deployment, applications development. Over the years, coordinator of several space research projects within national programs. Member of the Integral SatCom Initiative platform. OA - The Astronomical Observatory of The Romanian Academy / Cluj Branch will provide the infrastructure for the optical surveillance subsystem. It is responsible for the electro-optical system setup, installation and operation. It will also participate to common optical & radio satellite tracking experiments. The Feleacu (Cluj) Observatory was included in the COSPAR World List of Satellite Tracking Stations (station no. 1132). ASR – The Romanian Space Agency is the Romanian Space Authority and it is deeply involved in national and international space research projects. It is mainly responsible for the preparatory actions regarding consortium participation to future FP7 and ESA projects. ASR is also participating to the system validation and applications development, the dissemination and promotion of project results and networking with other international space projects. It will explore potential space applications and possible developments of the satellite surveillance system. URSA Project