Taller de Diseño de Picosatélites (CUBESATS) y Estaciones de Tierra Segmento de Tierra Ana Laverón Simavilla E-USOC/Dpto. de Vehículos Aeroespaciales ETSI de Aeronáuticos, UPM Taller de Diseño de Picosatélites (CUBESATS) y Estaciones de Tierra. AuthorsNames 1 Contents • Introduction • Basic description of the Ground Segment • Design considerations – – – – – – – Coverage required per S/C Type of orbit/mission Number of S/Cs Number of P/Ls and data processing needs Manned or unmanned missions Number and location of Ground Stations Security issues • Ground Segment requirements • Cost reduction scenarios Taller de Diseño de Picosatélites (CUBESATS) y Estaciones de Tierra. Ana Laverón Simavilla 2 Contents • • • • Ground segment definition and functions High level architecture. Core elements Alternative architectures for different missions Ground segment phases Taller de Diseño de Picosatélites (CUBESATS) y Estaciones de Tierra. Ana Laverón Simavilla 3 INTRODUCTION Taller de Diseño de Picosatélites (CUBESATS) y Estaciones de Tierra. Ana Laverón Simavilla 4 Space system • Space segment • Ground segment – Infrastructure and systems needed to operate the space segment – Link between the final users and the space segment • Users segment Taller de Diseño de Picosatélites (CUBESATS) y Estaciones de Tierra. Ana Laverón Simavilla 5 Relevance of the Ground Segmet • Importance of Ground Segment in Satellite Communications – Until not long ago, satellites were based on a relatively simple architecture, i.e., the bent-pipe design – The introduction of some satellite constellations and on-board processing started to become really complicated for the satellite industry • Some architectures have very complex Space Segment • Some architectures adopted simpler Space Segment and more complex Ground Segment – According to ESA • 80% of the satellite communications market is in the ground segment - sale of satellite terminal equipment and provision of valueadded services • 20% space segment itself - satellite production, launch and operations – The satellite and space industry lives in a contradiction: while people’s attention is often focused on the space segment, it is the ground segment that does a lot of the work that adds value to satellite communications Taller de Diseño de Picosatélites (CUBESATS) y Estaciones de Tierra. Ana Laverón Simavilla 6 Relevance of the Ground Segment • Criticality of SW design Ground Space Requirements Functionality Real-time embedded Interoperability P/L specific Autonomy Reuse bus Architecture Distributed network Processor constrained Integration More COTS Standard bus interfaces More external interfaces Team Dispersed 1 or 2 teams Different processes Code size 2.0-4.0 M SLOC 0.01-0.5 M SLOC Taller de Diseño de Picosatélites (CUBESATS) y Estaciones de Tierra. Ana Laverón Simavilla Ground Software is Highest Risk!!! 8 BASIC DESCRIPTION OF THE GROUND SEGMENT Taller de Diseño de Picosatélites (CUBESATS) y Estaciones de Tierra. Ana Laverón Simavilla 9 Space system main blocks Ground segment Operations support Spacecraft operations Payload operations Space segment End users Mission operations TM/TC Users data Data management TM/TC Ground Station TM/TC Taller de Diseño de Picosatélites (CUBESATS) y Estaciones de Tierra. Ana Laverón Simavilla 10 Ground Segment main elements • • • Ground Stations – Tracking – Reception of TM (HR & LR from P/L & S/C) – Uplink of TC (P/L & S/C) Control Centers – Mission Control – P/L Operations – S/C Operations – Coordination of Ground Stations – Data archiving – Data processing Final users – Telecommunication users – Scientists – … Taller de Diseño de Picosatélites (CUBESATS) y Estaciones de Tierra. Ana Laverón Simavilla 11 Data management paths Ground segment Command & Tracking data Requests Operations support Mission data H&S TM End users Mission data Data Relay Space segment Mission data Taller de Diseño de Picosatélites (CUBESATS) y Estaciones de Tierra. Ana Laverón Simavilla 12 DESIGN CONSIDERATIONS Taller de Diseño de Picosatélites (CUBESATS) y Estaciones de Tierra. Ana Laverón Simavilla 13 Design considerations • Coverage required per S/C • Type of orbit/mission • Number of S/Cs • Number of P/Ls and data processing needs • Manned or unmanned mission • Number and location of Ground Stations • Security issues Taller de Diseño de Picosatélites (CUBESATS) y Estaciones de Tierra. Ana Laverón Simavilla 14 Design considerations • Coverage required per S/C • Type of orbit/mission • Number of S/Cs • Number of P/Ls and data processing needs • Manned or unmanned mission • Number and location of Ground Stations • Security issues Taller de Diseño de Picosatélites (CUBESATS) y Estaciones de Tierra. Ana Laverón Simavilla 15 Coverage required per S/C 1/6 • Coverage: frequency and amount of time per orbit that a S/C needs to be linked to the GS – It depends on many factors • Amount of data to be transferred – TC and housekeeping TM is not an issue – P/L data can be an issue – Data rate of the downlink • S/C Autonomy – Lack of onboard command storage – Requirement to receive mission data • Manned missions • Need of continuous access, e.g. telecommunications S/Cs • Phase of the mission (e.g. LEOP) – It can determine the number and location of the Ground Stations Taller de Diseño de Picosatélites (CUBESATS) y Estaciones de Tierra. Ana Laverón Simavilla 16 Coverage required per S/C 2/6 • Coverage study – Circle of accessibility: it depends on the Ground Station (, minimum elevation) and the S/C (h, altitude) Taller de Diseño de Picosatélites (CUBESATS) y Estaciones de Tierra. Ana Laverón Simavilla 17 Coverage required per S/C 3/6 Coverage area from Torrejón and Maspalomas (=5º) – Solid lines – INGENIO (Sun-synchronous, 667,78 km) – Dashed lines – PAZ (Sun-synchronous, 510 km) Taller de Diseño de Picosatélites (CUBESATS) y Estaciones de Tierra. Ana Laverón Simavilla 18 Coverage required per S/C 4/6 – Passes over the station (e.g. EURECA daily passes) • Number of consecutive passes • Duration of the passes Taller de Diseño de Picosatélites (CUBESATS) y Estaciones de Tierra. Ana Laverón Simavilla 19 Coverage required per S/C 5/6 Three first orbits of ERS-1 ( i=98.5º, h=785 km) during the Launch and Early Orbit Phase (LEOP) Taller de Diseño de Picosatélites (CUBESATS) y Estaciones de Tierra. Ana Laverón Simavilla 20 Coverage required per S/C 6/6 • How can the coverage influence the Ground Station design or selection? 1. Determine the P/L data to be transfered (e.g. Biomass) a) P/L data rate (e.g.: 102 Mbps ) b) Duty cycle (e.g.: 20%) 2. Select a Ground Station location (e.g. Svalbard, Norway for Biomass) a) Study the coverage i. ii. 3. 4. Frequency of the passes Duration of each pass From 1. and 2. determine the downlink data rate needed (e.g. 100-250 Mb/s) Does the selected Ground Station meet the requirement? Taller de Diseño de Picosatélites (CUBESATS) y Estaciones de Tierra. Ana Laverón Simavilla 21 Design considerations • Coverage required per S/C • Type of orbit/mission • Number of S/Cs • Number of P/Ls and data processing needs • Manned or unmanned mission • Number and location of Ground Stations • Security issues Taller de Diseño de Picosatélites (CUBESATS) y Estaciones de Tierra. Ana Laverón Simavilla 22 Type of orbit/mission 1/6 • Each type of orbit/mission can make use of different communication links, each type of link require different Ground Station setups – LEO, MEO Store and forward link Crosslink in communication satellite systems Make use of available communication services Air Force Satellite Control Network (AFSCN) NASA Tracking and Data Relay Satellite System (TDRSS) – Molniya – GEO Store and forward link Ground Station relays Crosslink in communication satellite systems Taller de Diseño de Picosatélites (CUBESATS) y Estaciones de Tierra. Ana Laverón Simavilla 23 Type of orbit/mission 2/6 – Space Science missions Store and forward link Make use of available communication services ESA Tracking Stations Network (ESTRACK) NASA Deep Space Network (DSN) Taller de Diseño de Picosatélites (CUBESATS) y Estaciones de Tierra. Ana Laverón Simavilla 24 Type of orbit/mission 3/6 • LEO with store and forward link – High transmission delay for communications with 1 S/C (Starsys) – Constellations with many gateways (Globalstar) – Reduced transmitter power due to low altitude – If the data amount is high • Many Ground Stations • Very high data rates Taller de Diseño de Picosatélites (CUBESATS) y Estaciones de Tierra. Ana Laverón Simavilla 25 Type of orbit/mission 4/6 • LEO with crosslink – – – – – – Used in communication satellite systems Large coverage area Possibility of polar coverage Highly survivable due to mutiple paths Reduced jamming susceptibility due to limited Earth view area Reduced transmitter power due to low altitude Taller de Diseño de Picosatélites (CUBESATS) y Estaciones de Tierra. Ana Laverón Simavilla 26 Type of orbit/mission 5/6 • GEO with GS relay • • • • • • No need to switch between satellites No need of antenna tracking High-cost launch High-cost satellite High-coverage No polar regions coverage Taller de Diseño de Picosatélites (CUBESATS) y Estaciones de Tierra. Ana Laverón Simavilla 27 Type of orbit/mission 6/6 • Molniya orbit – – – – – Coverage in high latitudes Low-cost launch Complex network control Need for GS antenna pointing Need for S/C handover Taller de Diseño de Picosatélites (CUBESATS) y Estaciones de Tierra. Ana Laverón Simavilla 28 Design considerations • Coverage required per S/C • Type of orbit/mission • Number of S/Cs • Number of P/Ls and data processing needs • Manned or unmanned mission • Number and location of Ground Stations • Security issues Taller de Diseño de Picosatélites (CUBESATS) y Estaciones de Tierra. Ana Laverón Simavilla 29 Number of S/Cs • Overlaps of S/Cs at the same Ground Station • Gaps between S/Cs passes – Should be enough to enable the change from one S/C to the other • Complex operations Taller de Diseño de Picosatélites (CUBESATS) y Estaciones de Tierra. Ana Laverón Simavilla 30 Design considerations • Coverage required per S/C • Type of orbit/mission • Number of S/Cs • Number of P/Ls and data processing needs • Manned or unmanned mission • Number and location of Ground Stations • Security issues Taller de Diseño de Picosatélites (CUBESATS) y Estaciones de Tierra. Ana Laverón Simavilla 31 Number of P/Ls and data processing needs 1/3 • The data user’s requirements determine the complexity of the distribution systems – Acceptable error rate – Acceptable delay receiving the • TM – “TM available in less than 3 hours after sensing” (impact on coverage requirement) • processed TM in different levels – “Level 3 TM available in less than 5 hours after sensing” (impact on data handling and P/L CC) • Number of final users • Location of the final users Taller de Diseño de Picosatélites (CUBESATS) y Estaciones de Tierra. Ana Laverón Simavilla 32 Number of P/Ls and data processing needs 2/3 • If the S/C has several instruments each user will probably need – – – – all the data from one of the P/Ls a small portion from the other P/Ls a portion of housekeeping TM a portion of Flight Dynamics TM • Different users will need data processed in different Levels • The data processing for higher levels require the knowledge and cooperation of scientists Taller de Diseño de Picosatélites (CUBESATS) y Estaciones de Tierra. Ana Laverón Simavilla 33 Number of P/Ls and data processing needs 3/3 • Committee on Data Management, Archiving and Computing (CODMAC) Data Level Definitions – Level 0: reconstructed, unprocessed instrument/payload data at full resolution; raw engineering measurements (any and all communications artifacts, e.g. synchronization frames, communications headers, duplicate data removed) – Level 1: reconstructed, unprocessed instrument data at full resolution, timereferenced, and annotated with ancillary information, including radiometric and geometric calibration coefficients and georeferencing parameters, e.g., platform ephemeric, computed and appended but not applied to the Level 0 data – Level 2: derived geophysical variables at the same resolution and location as the Level 1 source data – Level 3: variables mapped on uniform space-time grid scales, usually with some completeness and consistency – Level 4: model output or results from analyses of lower level data (i.e., variables derived from multiple measurements) • Some others – Raw TM: as downlinked from the S/C – Level 1B: Level 1 data processed to sensor units Taller de Diseño de Picosatélites (CUBESATS) y Estaciones de Tierra. Ana Laverón Simavilla 34 Design considerations • Coverage required per S/C • Type of orbit/mission • Number of S/Cs • Number of P/Ls and data processing needs • Manned or unmanned mission • Number and location of Ground Stations • Security issues Taller de Diseño de Picosatélites (CUBESATS) y Estaciones de Tierra. Ana Laverón Simavilla 37 Manned or unmanned mission • Security requirements • Safety requirements • Safe return of astronauts • 24x7 Ops coverage vs. Automated Ops Taller de Diseño de Picosatélites (CUBESATS) y Estaciones de Tierra. Ana Laverón Simavilla 38 Design considerations • Coverage required per S/C • Type of orbit/mission • Number of S/Cs • Number of P/Ls and data processing needs • Manned or unmanned mission • Number and location of Ground Stations • Security issues Taller de Diseño de Picosatélites (CUBESATS) y Estaciones de Tierra. Ana Laverón Simavilla 39 Number and location of Ground Stations • Existing or new • Dedicated or shared • Fixed or mobile Taller de Diseño de Picosatélites (CUBESATS) y Estaciones de Tierra. Ana Laverón Simavilla 40 Design considerations • Coverage required per S/C • Type of orbit/mission • Number of S/Cs • Number of P/Ls and data processing needs • Manned or unmanned mission • Number and location of Ground Stations • Security issues Taller de Diseño de Picosatélites (CUBESATS) y Estaciones de Tierra. Ana Laverón Simavilla 41 Security issues • End-to-end lines • Use of the www Taller de Diseño de Picosatélites (CUBESATS) y Estaciones de Tierra. Ana Laverón Simavilla 42 GROUND SEGMENT REQUIREMENTS Taller de Diseño de Picosatélites (CUBESATS) y Estaciones de Tierra. Ana Laverón Simavilla 43 Ground segment requirements 1/2 • Ground segment requisites – Support the operations, data processing and handling with • High reliability • High availability • High fidelity • High flexibility • High security – Cost reasons will reduce some/all of the above characteristics of the GS • Cost considerations – Operations 30-40% of the overall programme Taller de Diseño de Picosatélites (CUBESATS) y Estaciones de Tierra. Ana Laverón Simavilla 44 Ground segment requirements 2/2 • Type of requirements – No loss of data • No missing passes • No missing data – Fast return of critical data – Regular return of bulk data – Rapid response for critical commanding – Ease of access to data – Data management security • Compromises to reduce redundacies and cost – Acceptance of small loss of passes (1 in 1000) – Acceptance of small loss of data (<1%) – No rapid return of non-urgent data (data available <3 hours after sensing) Taller de Diseño de Picosatélites (CUBESATS) y Estaciones de Tierra. Ana Laverón Simavilla 45 COST REDUCTION SCENARIOS Taller de Diseño de Picosatélites (CUBESATS) y Estaciones de Tierra. Ana Laverón Simavilla 46 Cost reduction scenarios 1/3 • Reliability – Some small passes loss and data loss should be accepted as they should not risk the mission, and enable important cost reduccions in redundant HW, SW and operations costs – This is not applicable to manned missions • Data availability – Real-time and near real time data is expensive, and should be reduced to the critical phases of the mission • Commisioning • Troubleshooting… – Processing and transferring the data in very short times is also very expensive by means of human resources (24x7) and communication links (bandwidths) Taller de Diseño de Picosatélites (CUBESATS) y Estaciones de Tierra. Ana Laverón Simavilla 47 Cost reduction scenarios 2/3 • Data management security – Security policies are also very expensive and its need should be evaluated carefully • Dedicated communication links • Operation support tools in secure networks • SW development – Increasing the ammount of COTS SW should reduce the development costs – Reuse of SW from previous similar missions should also be increased Taller de Diseño de Picosatélites (CUBESATS) y Estaciones de Tierra. Ana Laverón Simavilla 48 Cost reduction scenarios 3/3 • Increase autonomy of operations to reduce manpower costs – – – – – – – – – Tracking Automatic retuning of the frequency set-up Automatic reception and storage of downlinked TM Automatic conversion of critical raw data to engineering units Automatic checking of critical data Automatic dialing to on-call engineers Automatic distribution of data to end users Automatic production of summary TM quality Uplink of automated procedures Taller de Diseño de Picosatélites (CUBESATS) y Estaciones de Tierra. Ana Laverón Simavilla 49 GROUND SEGMENT DEFINITION AND FUNCTIONS Taller de Diseño de Picosatélites (CUBESATS) y Estaciones de Tierra. Ana Laverón Simavilla 50 Ground segment Definition ECSS-E-70 all ground facilities and personnel involved in the preparation or execution of mission operations Taller de Diseño de Picosatélites (CUBESATS) y Estaciones de Tierra. Ana Laverón Simavilla 51 Mission operations Comprise the subset of mission engineering activities identifiable for: – flight operations – ground operations – logistics engineering required to operate the space segment. Taller de Diseño de Picosatélites (CUBESATS) y Estaciones de Tierra. Ana Laverón Simavilla 52 Ground segment composition Ground Segment Domain Ground Segment Entity A Ground Operations Organization Element Element Element Space Operations Organization Element Element Element Organization A Entity B Ground Systems Space Segment Facility A Element Element Element Element Element Organization B Element Element Element Facility B Taller de Diseño de Picosatélites (CUBESATS) y Estaciones de Tierra. Ana Laverón Simavilla 53 Mission operations and mission success • Ground systems and operations are key elements of a space system and as such play an essential role in achieving mission success. • Mission success is defined as the achievement of the target mission objectives as expressed in terms of the quantity, quality and availability of delivered mission products and services within a given cost envelope. • Mission success requires successful completion of a long and complex process covering the definition, design, implementation, validation, in flight operations and post operational activities, involving both the ground segment and also space segment elements. • It involves technical activities, as well as human and financial resources, and encompasses the full range of space engineering disciplines. Moreover it necessitates a close link between the design of the ground segment and the space segment in order to ensure proper compatibility between both elements of the complete space system. Taller de Diseño de Picosatélites (CUBESATS) y Estaciones de Tierra. Ana Laverón Simavilla 54 Ground systems Definition ECSS-E-70 All ground infrastructure elements that are used to support the preparation activities leading up to mission operations, the conduct of mission operations and all post-operational activities Taller de Diseño de Picosatélites (CUBESATS) y Estaciones de Tierra. Ana Laverón Simavilla 55 Functions of the Ground Segment • Maintain RF communications links • Provide S/C control to ground operators • Process and archive telemetry (Tracking, Health & Safety) • Provide P/L control to ground operators • Process and archive telemetry (P/L data) • Support Mission Operations • Provide P/L data to the end users • Provide communications between CCs Taller de Diseño de Picosatélites (CUBESATS) y Estaciones de Tierra. Ana Laverón Simavilla 56 Functions of the Ground Segment • Provide S/C control to ground operators – Number of S/C and orbital configurations – Tracking methods • Range and range rate • Antenna viewing angles • External tracking network • Spacecraft autonomy • Provide P/L control to ground operators – Number of P/Ls – Number and location of P/L control centers Taller de Diseño de Picosatélites (CUBESATS) y Estaciones de Tierra. Ana Laverón Simavilla 57 Functions of the Ground Segment • Process and archive telemetry (P/L data) – – – – Number and location of expert centers Amount of data generated by the P/Ls Delay between data acquisition and data submittal to users Processing complexity • On board • On ground Taller de Diseño de Picosatélites (CUBESATS) y Estaciones de Tierra. Ana Laverón Simavilla 58 Functions of the Ground Segment • Provide P/L data to the end users – Number and location of users – Amount of data to be delivered to the users – Direct link or processed data • Communications between CCs – – – – – TM TC Voice Video Mail Taller de Diseño de Picosatélites (CUBESATS) y Estaciones de Tierra. Ana Laverón Simavilla 59 HIGH LEVEL ARCHITECTURE. CORE ELEMENTS Taller de Diseño de Picosatélites (CUBESATS) y Estaciones de Tierra. Ana Laverón Simavilla 60 Ground system elements • The facilities point of view • The data flow point of view • The SW elements point of view • The functional point of view • … Taller de Diseño de Picosatélites (CUBESATS) y Estaciones de Tierra. Ana Laverón Simavilla 61 Ground system elements MPS STC EGOS ESA Ground Operations Software System Taller de Diseño de Picosatélites (CUBESATS) y Estaciones de Tierra. Ana Laverón Simavilla 62 Ground system elements 1. Mission control system (MCS) 2. Mission exploitation system (MES) 3. Ground station system (GSTS) 4. Ground communication subnet (GCS) 5. Space & Ground simulation system (SGSS) 6. Electrical ground support equipment (EGSE) Ground Segment GCS Mission Control System (MCS) Ground Communications Subnet (GCS) Ground Station System (GSTS) Space & Ground Simulation System (SGSS) Space subnet link Space subnet link GCS Mission Exploitation System (MES) Space Segment GCS Electrical Ground Support Equipment (EGSE) Platform Payload AIT subnet Taller de Diseño de Picosatélites (CUBESATS) y Estaciones de Tierra. Ana Laverón Simavilla Assembly integration and test subnet 63 Ground system elements 1. Mission control system (MCS) 2. Mission exploitation system (MES) 3. Ground station system (GSTS) 4. Ground communication subnet (GCS) 5. Space & Ground simulation system (SGSS) 6. Electrical ground support equipment (EGSE) Ground Segment GCS Mission Control System (MCS) Ground Communications Subnet (GCS) Ground Station System (GSTS) Space & Ground Simulation System (SGSS) Space subnet link Space subnet link GCS Mission Exploitation System (MES) Space Segment GCS Electrical Ground Support Equipment (EGSE) Platform Payload AIT subnet Taller de Diseño de Picosatélites (CUBESATS) y Estaciones de Tierra. Ana Laverón Simavilla Assembly integration and test subnet 64 Mission control system (MCS) Elements required to control the mission and to exploit the products, which are: - Operations control system (OCS) a. Flight dynamics (FDS) - Payload control system (PCS) - Data distribution - Data base - Mission exploitation system (MES) Taller de Diseño de Picosatélites (CUBESATS) y Estaciones de Tierra. Ana Laverón Simavilla 65 Mission control system (MCS) Operations control system (OCS) supporting a. Flight operations b. Ground operations c. Mission control d. Analysis of performance of the mission e. Analysis of the performance of the system f. Control over the system configuration Taller de Diseño de Picosatélites (CUBESATS) y Estaciones de Tierra. Ana Laverón Simavilla 66 Mission control system (MCS) Flight dynamics system (FDS) a. Prediction of orbital elements b. Attitude determination c. Manoeuvres planning and specification of all the operational stages - LEOP - DRIFT - Commissioning - Nominal operations d. Prediction of antenna visibility e. Acquisition and processing of external geophysical and dynamical data f. Prediction of relevant operational events Taller de Diseño de Picosatélites (CUBESATS) y Estaciones de Tierra. Ana Laverón Simavilla 67 Mission control system (MCS) Payload control system (PCS) supporting a. Planning of the payload elements b. Monitoring and control of the payload elements c. Performance evaluation of the payload elements Taller de Diseño de Picosatélites (CUBESATS) y Estaciones de Tierra. Ana Laverón Simavilla 68 Ground system elements Relations between main MCS elements le le du du he he sc k sc ry TC lin to s e h i s su l t ac Sp TC re TC Tr ac TM An N ki n te av g nn ig da a atio ta po n int el ing em co e n m ts m an ds OCS Navigation requests FDS MPS Flight schedules, updates & plans Taller de Diseño de Picosatélites (CUBESATS) y Estaciones de Tierra. Ana Laverón Simavilla 69 Mission control system (MCS) Data distribution - Repository of all the data collected during the mission lifetime Mission data Base - Definition of all the mission data Taller de Diseño de Picosatélites (CUBESATS) y Estaciones de Tierra. Ana Laverón Simavilla 70 Data distribution system (DDS) • Instrument data processing for 3 instruments Mission Data 1 Mbps Instrument A Data Buffer & Deconmutator User A Conmutator 500 kbps 520 kbps Recorder 520 kbps Decrypter 10 kbps 1 Mbps Instrument Data Deconmutator Instrument B Data Buffer & Deconmutator User A Conmutator 700 kbps 722 kbps Recorder 722 kbps 8 kbps 12 kbps Instrument B Data Buffer & Deconmutator 1 Mpbs User A Conmutator 1018 kpbs Taller de Diseño de Picosatélites (CUBESATS) y Estaciones de Tierra. Ana Laverón Simavilla Recorder 1018 kpbs 71 Data distribution system (DDS) • Data processing Ground Segment FOCC FO Data HK Data MCC P/L CC SC Data HK Data Deconmutator for Instrument A, Data Buffer, & Processing Decrypter FO Data Deconmutator for Instrument A, Data Buffer, & Processing Calibration/ Data Instrument A Expert Center 1 Mbps Instrument Data Deconmutator Data for Other Instruments Instrument A Data Buffer, Deconmutator & Processing Instrument A Data Buffer, Conmutator & Processing Instrument A Data for other instruments Other Instruments Data Instrument A Data Buffer, Conmutator & Processing Taller de Diseño de Picosatélites (CUBESATS) y Estaciones de Tierra. Ana Laverón Simavilla Requests/ Processed Data Users community 72 Ground system elements 1. Mission control system (MCS) 2. Mission exploitation system (MES) 3. Ground station system (GSTS) 4. Ground communication subnet (GCS) 5. Space & Ground simulation system (SGSS) 6. Electrical ground support equipment (EGSE) Ground Segment GCS Mission Control System (MCS) Ground Communications Subnet (GCS) Ground Station System (GSTS) Space & Ground Simulation System (SGSS) Space subnet link Space subnet link GCS Mission Exploitation System (MES) Space Segment GCS Electrical Ground Support Equipment (EGSE) Platform Payload AIT subnet Taller de Diseño de Picosatélites (CUBESATS) y Estaciones de Tierra. Ana Laverón Simavilla Assembly integration and test subnet 73 Mission exploitation system (MES) Provide users with mission products - Raw data (images, TM) Rectified data (geometrically and radiometrically) using satellite housekeeping TM and other PL housekeeping TM Long term archive, for generation of products and for dissemination to users Statistic about the quality of the data, and reports of the mission performance Supporting the users establishing high level production plan Taller de Diseño de Picosatélites (CUBESATS) y Estaciones de Tierra. Ana Laverón Simavilla 74 Ground system elements 1. Mission control system (MCS) 2. Mission exploitation system (MES) 3. Ground station system (GSTS) 4. Ground communication subnet (GCS) 5. Space & Ground simulation system (SGSS) 6. Electrical ground support equipment (EGSE) Ground Segment GCS Mission Control System (MCS) Ground Communications Subnet (GCS) Ground Station System (GSTS) Space & Ground Simulation System (SGSS) Space subnet link Space subnet link GCS Mission Exploitation System (MES) Space Segment GCS Electrical Ground Support Equipment (EGSE) Platform Payload AIT subnet Taller de Diseño de Picosatélites (CUBESATS) y Estaciones de Tierra. Ana Laverón Simavilla Assembly integration and test subnet 75 Ground Station system (GSTS) It is the direct interface with the space segment while in orbit, and with the MCS. It provides support functions for controlling the space segment elements and exploiting the mission products Logical instances: a. GSTS-SSC: in support of space segment control for the platform and payload b. GSTS-ME: in support of mission exploitation Taller de Diseño de Picosatélites (CUBESATS) y Estaciones de Tierra. Ana Laverón Simavilla 76 Ground station system (GSTS) − RF chains (uplink/downlink) dealing with the transmission/reception of signal to/from the space segment Ground Station Antenna − Baseband units performing modulation/demodulation of the signals to/from the space segment RF Equipment TM/TC Processors − RF and baseband units performing the tracking Station M & C Taller de Diseño de Picosatélites (CUBESATS) y Estaciones de Tierra. Ana Laverón Simavilla 77 Ground station system (GSTS) • Routine navigation of a spacecraft around the Solar System relies on two tracking methods: ranging and two-way Doppler - Precisely measuring the time it takes radio signals to travel to and from a spacecraft gives the distance from the ground station;‘two-way range’. (Random errors down to 1 m) - measuring the signal’s Doppler shift provides the craft’s velocity along that line-of-sight; ‘range-rate’. (Random errors down to 0,1 mm/s) Taller de Diseño de Picosatélites (CUBESATS) y Estaciones de Tierra. Ana Laverón Simavilla 78 Ground station system (GSTS) • The other two position coordinates, against the sky background, are obtained only indirectly from the motion of the ground station as the Earth rotates • The craft’s velocity components in the plane-of-sky are not measured and can only be found from how the position changes from day to day Taller de Diseño de Picosatélites (CUBESATS) y Estaciones de Tierra. Ana Laverón Simavilla 79 Ground station system (GSTS) • Angular spacecraft positioning can be measured using two widely separated antennas to simultaneously track a transmitting probe: Differential One-way Range (DOR) – Delta-DOR corrects errors “tracking” a quasar in a direction close to the spacecraft for calibration. (Errors down to 500 billionths of a degree/nanoradian) Taller de Diseño de Picosatélites (CUBESATS) y Estaciones de Tierra. Ana Laverón Simavilla 80 Ground station system (GSTS) − Processing elements to perform the handling of the data sent by the MCS that has to be transmitted to the space segment Ground Station Antenna − Processors dealing with the formating of the data structures (packets) to be transmited to the MCS RF Equipment TM/TC Processors Station M & C − Processors/processes dealing with the monitoring and control of the network elements − Calibration units to verify the station performances − Test units Taller de Diseño de Picosatélites (CUBESATS) y Estaciones de Tierra. Ana Laverón Simavilla 81 Ground station system (GSTS) − From the reception stand-point Ground Station a. b. c. d. e. Antenna RF Equipment Conditioning Filtering Sychronisation Demultiplexing Packetization of the downlinked data TM/TC Processors Station M & C − From the transmition point of view a. Check data streams generated within the GS b. Modulate the signals c. Amplify the signals Taller de Diseño de Picosatélites (CUBESATS) y Estaciones de Tierra. Ana Laverón Simavilla 82 Ground system elements 1. Mission control system (MCS) 2. Mission exploitation system (MES) 3. Ground station system (GSTS) 4. Ground communication subnet (GCS) 5. Space & Ground simulation system (SGSS) 6. Electrical ground support equipment (EGSE) Ground Segment GCS Mission Control System (MCS) Ground Communications Subnet (GCS) Ground Station System (GSTS) Space & Ground Simulation System (SGSS) Space subnet link Space subnet link GCS Mission Exploitation System (MES) Space Segment GCS Electrical Ground Support Equipment (EGSE) Platform Payload AIT subnet Taller de Diseño de Picosatélites (CUBESATS) y Estaciones de Tierra. Ana Laverón Simavilla Assembly integration and test subnet 83 Ground communications subnetwork (GCS) It connects all operational ground facilities. a. Commnunications equipment to send/receive data b. Communication lines and services Other subnetworks are: a. Space link subnet b. AIT subnet Taller de Diseño de Picosatélites (CUBESATS) y Estaciones de Tierra. Ana Laverón Simavilla 84 Ground system elements 1. Mission control system (MCS) 2. Mission exploitation system (MES) 3. Electrical ground support equipment (EGSE) 4. Ground station system (GSTS) 5. Ground communication subnet (GCS) 6. Space & Ground simulation system (SGSS) Ground Segment GCS Mission Control System (MCS) Ground Communications Subnet (GCS) Ground Station System (GSTS) Space & Ground Simulation System (SGSS) Space subnet link Space subnet link GCS Mission Exploitation System (MES) Space Segment GCS Electrical Ground Support Equipment (EGSE) Platform Payload AIT subnet Taller de Diseño de Picosatélites (CUBESATS) y Estaciones de Tierra. Ana Laverón Simavilla Assembly integration and test subnet 85 Space and ground simulation facility (SSF) - It supports the validation of critical operational data a. Databases b. Procedures Radiometer auxiliary data - It supports training activities Gr ou m nd s on e ito gm ri n e n g t t en m g g se r i n e to ac oni p S m et g mn e s s ce Spa mmand co Ground s e g mn e t c o mma nds SSF Taller de Diseño de Picosatélites (CUBESATS) y Estaciones de Tierra. Ana Laverón Simavilla 86 Ground system elements 1. Mission control system (MCS) 2. Mission exploitation system (MES) 3. Ground station system (GSTS) 4. Ground communication subnet (GCS) 5. Space & Ground simulation system (SGSS) 6. Electrical ground support equipment (EGSE) Ground Segment GCS Mission Control System (MCS) Ground Communications Subnet (GCS) Ground Station System (GSTS) Space & Ground Simulation System (SGSS) Space subnet link Space subnet link GCS Mission Exploitation System (MES) Space Segment GCS Electrical Ground Support Equipment (EGSE) Platform Payload AIT subnet Taller de Diseño de Picosatélites (CUBESATS) y Estaciones de Tierra. Ana Laverón Simavilla Assembly integration and test subnet 87 Electric ground support equipment (EGSE) It is part of the overall ground support equipment (GSE), supporting the verification of the space segment during assembly, integration and test (AIT) It supports operations in the use of the GMs MDB M&C Simulator EGSE Taller de Diseño de Picosatélites (CUBESATS) y Estaciones de Tierra. Ana Laverón Simavilla 88 ALTERNATIVE ARCHITECTURES FOR DIFFERENT MISSIONS Taller de Diseño de Picosatélites (CUBESATS) y Estaciones de Tierra. Ana Laverón Simavilla 89 • James Webb Telescope GS (launch 2013) • MSG GS – Facilities diagram – Functional block diagram • ISS GS – Columbus GS – ATV GS • COTS GS Taller de Diseño de Picosatélites (CUBESATS) y Estaciones de Tierra. Ana Laverón Simavilla 90 JWT GS Science and Operations Center (SOC) S ban - Recorder data - Nominal TM stream X-band d Ephemerides - Commands Observations Observation plan FSW loads Ranging/tracking Contingency TM stream DSN schedule Commands FSW loads Recorder data files Observation plans Flight Operations Center (FOS) Command & Telemetry System (CTS) Actuators Cmds Proposal Planning System (PPS) Recorder Data files Proposals Payload control system TM Goldstone - Recorder data files - TM stream - Ranging/tracking Observatory test-bed (OTB) Camberra Ephemerides Madrid Cmd Level 0 processing of recorder data Project Reference Database Management System (PRD MS) FSW loads PRD Data TM PL image data Data Management System (DMS) Data products PRD Data PRD Data - Commands - Ranging/tracking New development Ranging/tracking Ephemerides Jet Propulsion Laboratory (JPL) Flight Dynamics Facility (FDF) Flight SW development labs JWT & NGST development Other developtmens - Cache recorder data - Schedule DSN resources Taller de Diseño de Picosatélites (CUBESATS) y Estaciones de Tierra. Ana Laverón Simavilla 91 MSG GS • Facilities diagram - Tracking - TM/TC (back-up) EGSE Back-up and Ranging Ground Station (BRGS) LEOP - TM/TC - Tracking Primary Ground Station (PGS) Back-up Satellite control center (BSCC) Central Facility (CF) Image Processing Facility (IMPF) Rectified images Satellite M&C Data Acquisition and Dissemination Facility (DADF) Products Meteorological Products Extraction Facility (MPEF) Products Rectified images Space and Ground Simulation Facility (SGSF) Raw & rectified images TM MSG Archive and Retrieval Facility (U-MARF) Ground Segment M&C Communications backbone Taller de Diseño de Picosatélites (CUBESATS) y Estaciones de Tierra. Ana Laverón Simavilla 92 MSG GS • Functional block diagram ete rd a tre m TM TC g Rangin Ra m dio s ata LEOP TM Image acquisition and processing S/C Monitor & Control Radiometer aux. data Flight dynamics data EGSE TC & TM Simulation data TC Space and Ground Segment Simulation Rectified & raw data Metereological product extraction Retrieval of products Products Archiving & Retrieval Retrieval of products Schedules & actiivities Calibration data Rectified data Retrieval of data Mission Planning & Scheduling GS Monitor & Control Operations preparation End user support center Simulation data M&C Retrieval of products Taller de Diseño de Picosatélites (CUBESATS) y Estaciones de Tierra. Ana Laverón Simavilla 93 ATV GS Taller de Diseño de Picosatélites (CUBESATS) y Estaciones de Tierra. Ana Laverón Simavilla 94 Columbus GS Taller de Diseño de Picosatélites (CUBESATS) y Estaciones de Tierra. Ana Laverón Simavilla 95 GROUND SEGMENT PHASES Taller de Diseño de Picosatélites (CUBESATS) y Estaciones de Tierra. Ana Laverón Simavilla 96 Ground segment phases 1/3 0/A B Mission analysis and feasibility Ground segment preliminary design - Identify characteristics, constraints, conceps. - Assess feasibility (GS perspective) - Precise definition of the GSB to confirm feasibility, prepare choice of suppliers, start the implementation - The GS is decomposed into its main elements PHASE OBJECTIVE ACTIVITIES REVIEWS INPUTS/OUTPUTS GS Requirements Review Mission RD GSRR GS Preliminary Design Review Mission Ops Concept (D) Customers RD (D) EGSE Requirements from the SSC Space-to-Ground ICD (D) GSPDR Customer RD GS Baseline Definition System definition Taller de Diseño de Picosatélites (CUBESATS) y Estaciones de Tierra. Ana Laverón Simavilla 97 Ground segment phases 2/3 PHASE C D GS Detailed design GS Production and Validation OBJECTIVE ACTIVITIES REVIEWS Production - GS Design to element level and start implementation -Definition of the ops. Org. And start of production of mission operations data Procure GS facilities and elements Integration and technical verification and validation Includes preliminary validation of mission data GSCDR Operational validation Train personnel Validate full GS ORR Ground Segment Implementation Operations Taller de Diseño de Picosatélites (CUBESATS) y Estaciones de Tierra. Ana Laverón Simavilla 98 Ground segment phases 3/3 PHASE OBJECTIVE ACTIVITIES REVIEWS E F Operations execution Disposal LEOP & commissioning Acquire mission orbit/configuration and quality space segment Routine operations Operate and exploit mission inorbit IOQR IOORs Space and Ground Segment disposal MCOR Operations Taller de Diseño de Picosatélites (CUBESATS) y Estaciones de Tierra. Ana Laverón Simavilla 99 GS preparation process Taller de Diseño de Picosatélites (CUBESATS) y Estaciones de Tierra. Ana Laverón Simavilla 100 BIBLIOGRAPHY Taller de Diseño de Picosatélites (CUBESATS) y Estaciones de Tierra. Ana Laverón Simavilla 101 Bibliography 1. Ground systems and operations – Part 1: Principles and requirements 2. Ground systems and operations – Part 2: Document requirements definition 3. James Webb Space Telescope Project. Mission Operations Concept Document 4. MSG Ground Segment Design Specification (GSDS) 5. EGOS, ESA Ground operations Software System, SpaceOps 2004, N. Peccia 6. Space mission analysis and design, J.R. Wertz and W.J. Larson 7. Spacecraft systems engineering, P. Fortescue and J. Stark Taller de Diseño de Picosatélites (CUBESATS) y Estaciones de Tierra. Ana Laverón Simavilla 102