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SLS AREA REPORT. SLS-OPT: Optical Communications Working Group Problem and Issues: None. However, schedule for standards publication is very aggressive. Planning: The following books have been started: Blue Book for Optical Communications Physical Layer
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SLS AREA REPORT • SLS-OPT: Optical Communications Working Group • Problem and Issues: • None. However, schedule for standards publication is very aggressive • Planning: • The following books have been started: • Blue Book for Optical Communications Physical Layer • Blue Book for Optical Communications Coding & Synchronization • Green Book for Optical communications Concepts and Terminologies • Green Book for Real-Time Weather and Atmospheric Characterization Data • Other planned books are • Green Book for Optical Communications Physical Layer • Green Book for Optical Communications Coding and Synchronization • Blue or Magenta Book(s) for Real-Time Weather and Atmospheric Characterization Data
SLS AREA REPORT SLS-OPT: Optical Communications Working Group (Continued) • Summary Progress: • ESA and DLR presented material on the TESAT Lasercom Terminal (LCT) implementation for possible consideration as part of the standard(s) • ESA and DLR derived a subset of the presented implementation as proposed input to the CCSDS Blue Books. • Space agencies were asked to review this proposal and provide complementary or any counter proposals prior to the Fall 2014 Meeting • NASA presented work done on the Lunar Laser Communication Demonstration (LLCD) and the Deep Space Optical Terminal (DOT) to help guide the discussion towards a low photon flux (high photon efficiency) standard • A lot of discussion and progress was made on the Green Book for Real Time Weather and Atmospheric Characterization Data • Planning for Fall 2014 Face-to-Face Meeting: • Space agencies have been invited to introduce a complimentary or counter proposal to the ESA / DLR proposal for the High Photon Flux (e.g. Near Earth) scenario • NASA will introduce a proposed standard to cover the Low Photon Flux (e.g. Deep Space trunk line) scenario • Continuation of work in the Blue and Green Books • 1st Draft of the Green Book for Real Time Weather will be reviewed
SLS AREA REPORT BACKUP
SLS AREA REPORT SLS-OPT: Optical Communications Working Group • ESA and DLR Proposal for High Photon Flux: • Base the standard on the European Data Relay Satellite System (EDRS) Laser Communication Terminal • User data rate at 1.8 Gbps • EDRS data relay service (EDRS-A, EDRS-C,…) will be operational in orbit for 20 plus years from 2015 • Preoperational tests with LCT on Alphasat since launch (July 2013) • Initial EDRS LEO users: Sentinel 1&2 series (A,B,C,D…) of Copernicus (EU- earth observation satellite prog.) • Sentinel 1A launch scheduled April 3rd 2014, 11pm EDRS Photo: ESA Sentinel 1A Photo: TAS-I/ ESA
SLS AREA REPORT SLS-OPT: Optical Communications Working Group • Green Book on Real-Time Weather and Atmospheric Characterization Data: • The Working Group defined a set of SIX minimum required measurements that can be collected using 4 specialized instruments, plus standard weather instruments: • Minimum measurements needed – Instruments required: • 1. Cloud/no cloud- Whole Sky Imager (Visible and Infrared , WSI) • 2. Attenuation - WSI / Ceilometer • 3. Cloud base height - Ceilometer • 4. Seeing parameters (r0) 24X7 (i.e., turbulence) - Differential Image Motion Monitor (DIMM) • 5. Aerosol/sky radiance - Sun photometer • 6. Standard Meteorological Parameters (u,v,p,t, q-- i.e., wind, pressure, temperature, specific humidity) and rain • We will also include information about other data types and instruments that are optional.
SLS AREA REPORT SLS-OPT: Optical Communications Working Group • Blue Books Organization: • The Working Group has decided to organize the Blue Books as follows • Original proposal for Blue Book on Physical Layer (Example): • Chapter X: High Photo Flux Scenario • Modulation(s) • Chapter Y: Low Photon Flux Scenario • Modulation(s) • Agreed to format (Example): • Chapter X: Phase Shift Keying • Chapter Y: Pulse Position Modulation • Chapter Z: On-Off Keying • Etc. • The Blue Book on Optical Communications and Synchronization will be formatted similarly • Phrases like High Photon Flux and Low Photon Flux (or High Data Throughput and High Photon Efficiency) will only be used in the Green Books. The Green or Magenta Books will explain which modulation is recommended to be used with which coding for a particular scenario