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Optical Communications Systems for NASA's Human Space Flight Missions

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Optical Communications Systems for NASA's Human Space Flight Missions https://ntrs.nasa.gov/search.jsp?R=20180007088 2019-08-31T18:09:13+00:00Z Optical Communications Systems for NASA’s Human Space Flight Missions Antonios Seas, Bryan Robinson, Tina Shih, Farzana Khatri, and Mark Brumfield Agenda • Introduction • Objectives & L1 Requirements • High Level System Architecture/Operational Characteristics • Modular, Agile, Scalable Optical Terminal (MAScOT) • Conclusion Laser-Enhanced Mission Communications Navigation and Operational Services (LEMNOS) LEMNOS Project Slide 2 LEMNOS Introduction • Space-based Optical Comm demonstrated on LADEE LLCD • LCRD is an Optical Comm Pathfinder LLCD Laser Comm • ILLUMA-T will establish a complete Optical Comm System on LADEE/Lunar Orbit LCRD/GEO O2O Laser Comm ILLUMA-T on Orion/Lunar Laser Comm Orbit O2O will take Terminal on ISS/LEO the next step LEMNOS Project Goal: and use optical Implement Optical Communications communications starting with demonstrations of for the Orion operational utility on Orion EM-2 (O2O) spacecraft as a and ISS (ILLUMA-T) Development Test Objective ILLUMA-T will be the first • (DTO) Ground Stations LEO user of the LCRD system • End to End operational demonstration of Optical Communication • 50 Mbps link to ISS from ground ** LLCD: Lunar Laser Communication Demonstration ** ILLUMA-T: Integrated LCRD LEO (Low-Earth Orbit) User Modem and Amplifier Terminal ** LCRD: Laser Communication Relay Demonstration ** LEMNOS: Laser-Enhanced Mission Communications Navigation and Operational Services ** O2O: Orion EM-2 Optical Communications Terminal LEMNOS Project Slide 3 Agenda • Introduction • Objectives & L1 Requirements • High Level System Architecture/Operational Characteristics • Modular, Agile, Scalable Optical Terminal (MAScOT) • Conclusion LEMNOS Project Slide 4 LEMNOS Projects ILLUMA-T O2O (Integrated LCRD LEO User Modem and Amplifier Terminal) (Orion EM-2 Optical Comm) Develop an optical communications Employ optical communications user terminal to demonstrate data capability for Orion series of transfer between low Earth orbit and spacecraft, starting with the the ground through a demonstration of operational geosynchronous relay utility on EM-2. 1.2 Gbps return 80 Mbps return 51 Mbps forward 20 Mbps forward To Ground via LCRD relay Direct to ground (WSC, TMF) Feb 2021 delivery to GSFC Nov 2020 delivery to KSC Mar 2022 Launch on SpaceX Dragon (TBR) June 2022 Launch on Orion/SLS ~ 6 months mission 8-21 day mission LEMNOS Project Slide 5 O2O Objective and L1 Requirements Objective: Implement optical communications capability for Orion series of spacecraft, starting with a demonstration of operational utility on EM-2 1.0 Develop an Optical Comm System to plan and demonstrate an operational optical comm link for Orion EM-2 2.0 Maintain a development path to a fully operational Optical Comm System 3.0 Flow data from Orion through the Optical Comm Fight Terminal to the Optical Comm Ground Terminal 4.0 Flow data from Optical Comm Ground Terminal to Optical Comm Fight Terminal and forward to Orion 5.0 Distribute data to/from Orion MCC real time or store and distribute later 6.0 Flight terminal conforms to the Orion accommodations, mission objectives, and environments 7.0 Ground terminal and data system developed with operational interfaces LEMNOS Project Slide 6 ILLUMA-T Objective and L1 Requirements Objective: The ILLUMA-T project shall develop an optical communications user terminal to demonstrate data transfer between low Earth orbit and the ground through a geosynchronous relay The ILLUMA-T project shall demonstrate a duplex optical communications link from the 1.1 ILLUMA-T terminal located on the ISS to a ground station via the LCRD satellite The ILLUMA-T user terminal shall operate up to 1.244 Gbit/s on the return link 1.2 (ISS to Ground) and up to 51 Mbps on the forward link (Ground to ISS) The ILLUMA-T protoflight terminal shall be developed using an approach that includes 1.3 participation of commercial companies and enables the transfer of optical communications technology to industry 1.4 The ILLUMA-T terminal orientation shall support line of sight to a ground station The ILLUMA-T terminal shall support a bi-directional data connection of at least 1.0 Gbit/s 1.5 (i.e. 100/1000 Mbps Ethernet connection) LEMNOS Project Slide 7 Agenda • Introduction • Objectives & L1 Requirements • High Level System Architecture/Operational Characteristics • Modular, Agile, Scalable Optical Terminal (MAScOT) • Conclusion LEMNOS Project Slide 8 O2O Implementation Crew Module Adaptor (CMA) 150° 120° Phased Array O2O Optical Module (OM) O2O Controller Antenna (PAA) (bracket interface TBD) Electronics Module (CEM) LEMNOS Project Slide 9 O2O Architecture LEMNOS Project Slide 10 ILLUMA-T Implementation ILLUMA-T Location on ISS (JEM-EF #3) ILLUMA-T (JEM-EF #3) LEMNOS Project Slide 11 ILLUMA-T Architecture LCRD ILLUMA-T Payload RF link Optical Data Links: Infrastructure TDRSS ISS Data I/F: Return: 1.2 Gbps Controller Ethernet Forward: 51 Mbps Electronics LCRD ISS Modem Infrastructure Optical RF link Module RF link Power Cmd & TLM I/F: Convertor Mil-STD-1553 JEM-EF Housing SN OGS-2 OGS-1 White Sands ILLUMA-T Operations Huntsville ILLUMA-T Located LCRD Operations Laser Space Lasercom Mission at White Support Center Terminal Console Ops Center (LMOC) (HOSC) (LSTC) Sands Located at MSFC Data to and from HOSC Laser Performance Analysis Center (LPAC) LEMNOS Project Slide 12 ILLUMA-T Payload Configuration ILLUMA-T Payload LEMNOS Project Slide 13 ILLUMA-T Space Terminal Elements Grapple H-Fixture Payload Controller Electronics (CE) Fiber Spool Assembly JEM Enclosure Interface Unit (FSA) (PIU) Sled Subassembly Modem (MM) Power Converter Unit (PCU) Dragon SC MAScOT (OM) Instrument Sled Interface OM Isolation & ATCS Cold Plates LEMNOS Project Slide 14 Agenda • Introduction • Objectives & L1 Requirements • High Level System Architecture/Operational Characteristics • Modular, Agile, Scalable Optical Terminal (MAScOT) • Conclusion LEMNOS Project Slide 15 Lasercom Terminal Evolution Assembled MAScOT EDU Latched MAScOT EDU LLCD Optical LCRD Modular, Agile, Module Optical Scalable Optical on LADEE Module Terminal (MAScOT)* 2009-2014 2011-Present 2013-Present NASA/MITLL developed Industry “build to print” of NASA/MITLL concept, industry- and demonstrated during LLCD-based terminal; to built; to be used in new Lunar Laser Comm Demo be used for Laser Comm programs with ISS and Orion; (LLCD) Relay Demo (LCRD) incorporates lessons learned from LLCD/LCRD *T. Shih, et al, “A Modular, Agile, Scalable Optical Terminal Architecture for Space Communications”, ICSOS 2017. LEMNOS Project Slide 16 Modular, Agile, Scalable Optical Terminal(MAScOT) Deep Space • Generic MAScOT goals: GEO 1. Increased coverage with faster slew rates • Accommodates short/fast LEO orbit links • Does not require spacecraft pointing to achieve comm link LEO 2. Modular • Customizable for given application • Lower reproduction/recurring costs • Enables future technology swap-outs 3. Scalable • Modularity helps make subsystems more readily scalable Modular, Agile, Scalable • Can accommodate near-Earth and/or Optical Terminal Deep Space applications without full- up architecture changes (MAScOT) 10-cm Terminal Architecture LEMNOS Project Slide 17 OM Subassembly Breakdown Fold Mirror Industry Assembly Telescope and Telescope Assembly (not shown) Relay Assembly Telescope Fold Mirror Star Tracker Star Tracker Relay Industry Elevation Yoke Latch Gimbal Assembly Relay Assembly Latch (not Azimuth Latch and Gimbal Assembly shown) Housing Assembly MIT LL Backend Optics Backend Assembly Optics Isolation MIT LL Assembly LEMNOS Project Slide 18 Agenda • Introduction • Objectives & L1 Requirements • High Level System Architecture/Operational Characteristics • Modular, Agile, Scalable Optical Terminal (MAScOT) • Conclusion LEMNOS Project Slide 19 Conclusion • The LEMNOS team represents a world recognized group aiming to advance the use of optical communications system for space communications • LEMNOS projects embody important opportunities to demonstrate key characteristics of optical communications based systems and are natural precursors to planned deployment of the next generation communications relay system (Optical TDRS) and Deep Space optical communications • By 2022 the LEMNOS project will deliver two optical communications terminals demonstrating operational utility of laser communications in both relay and direct to Earth scenarios GO LEMNOS! LEMNOS Project Slide 20 BACKUP SLIDES LEMNOS Project Slide 21.
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