Скачать презентацию NASA Mars Exploration Mission Operations Concepts Greg Kazz Скачать презентацию NASA Mars Exploration Mission Operations Concepts Greg Kazz

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NASA Mars Exploration Mission Operations Concepts Greg Kazz Chad Edwards NASA/JPL 18 Jan 2007 NASA Mars Exploration Mission Operations Concepts Greg Kazz Chad Edwards NASA/JPL 18 Jan 2007 Mars Bo. F - CCSDS Jan 2007 Meeting - Colorado Springs cde-

MER (Spirit and Opportunity) • Telecom configuration – X-band: 15 W SSPA; LGA, 28 MER (Spirit and Opportunity) • Telecom configuration – X-band: 15 W SSPA; LGA, 28 cm steered HGA – UHF: CE-505 txcvr; monopole antenna • EDL – X-band MFSK tones to DSN (~1 bps effective info rate) – 8 kbps UHF simplex – link to MGS after backshell separation • Surface ops – Low-latitude landing sites - Spirit (15˚S, 175˚E), Opportunity (2˚S, 354˚E) – X-band DFE commanding each Martian morning – Afternoon telemetry return via X-band DTE and/or UHF relay via ODY (reliable) or MGS (unreliable) to support next sol(s) planning • At this point, nearly all data return is via ODY relay – Additional telemetry return via overnight ODY/MGS relay passes as allowed by rover energy budget – Typical 100 -200 Mb/sol data return via 1 -2 UHF relay passes • Most passes @ 128 kbps; some ODY passes supportable at 256 kbps – Prox-1 User-defined data mode (bitstream structured as DTE TM frames) Mars Bo. F - CCSDS Jan 2007 Meeting - Colorado Springs 2 18 Jan 2007

Mars Reconnaissance Orbiter • MRO represents the latest instance of a core Mars Exploration Mars Reconnaissance Orbiter • MRO represents the latest instance of a core Mars Exploration Program strategic science orbiter, equipped with relay capability – Long lifetime (6 yrs nominal; consumables for 10 yrs) – First flight of Electra UHF transceiver, Software-Defined Radio with in-flight reprogrammability – Low-altitude polar orbit for science, 3 PM/3 AM orbit plane • End-to-end protocol suite – CCSDS Prox-1 protocol on prox link • Reliable and unreliable modes supported • Currently only user-defined data mode supported • Post-launch upgrade to implement Adaptive Data Rate functionality is planned for support of MSL – Deep space link • AOS link layer • Unacknowledged CFDP provides pass-level accountability information – Relay operations • Nadir attitude, or roll steering (up to +- 30 deg) for enhanced relay performance Mars Bo. F - CCSDS Jan 2007 Meeting - Colorado Springs 3 18 Jan 2007

Phoenix (PHX) • Telecom configuration – UHF-only after cruise stage separation – CE-505 UHF Phoenix (PHX) • Telecom configuration – UHF-only after cruise stage separation – CE-505 UHF txcvr, helix and monopole antennas • EDL – 8, 32 kbps UHF simplex link to MGS (open loop carrier detect, closed loop demod), MRO (open loop demod), MEX (open loop carrier detect) • Surface ops – High-latitude site (65˚ - 72˚N) offers many contact opportunities from polar relay orbiters (ODY and MRO) – 90 sol surface lifetime – Requirements: • 60 Mb/sol telemetry return in 2 passes (>30 Mb in afternoon LMST pass for overnight planning of next sol); • 1 Mb/sol command load each morning (LMST) – Prox link configuration: reliable link, 8 k uncoded forward/128 k coded return; user-defined data mode (bitstream structured as DTE TM frames) Mars Bo. F - CCSDS Jan 2007 Meeting - Colorado Springs 4 18 Jan 2007

Mars Science Laboratory (MSL) • Telecom configuration – X-band: 100 W TWTA (cruise/EDL), 15 Mars Science Laboratory (MSL) • Telecom configuration – X-band: 100 W TWTA (cruise/EDL), 15 W SSPA (surface); LGA, MER-class steered HGA – UHF: Electra-Lite txcvr; quadrifilar helix antenna • EDL – X-band DTE MFSK tones from cruise stage sep thru landing or occultation (~1 bps effective info rate) – High rate (≥ 2 kbps) UHF simplex link to MRO • Surface ops – Landing site TBD (± 45˚ latitude range) – 1 Mars Year design surface ops lifetime – Nominal ops concept: • X-band DFE command pass each Martian morning (225 kb/sol) • 3 PM MRO UHF relay pass for return critical telemetry to support planning for next sol; additional MRO relay return at 3 AM MRO pass • 250 Mb/sol aggregate data return requirement • Prox link configuration (MRO primary): reliable link, Adaptive Data Rate, 1 - 1024 kbps, user-defined data mode (bitstream structured as DTE TM frames) Mars Bo. F - CCSDS Jan 2007 Meeting - Colorado Springs 5 18 Jan 2007

2 nd Decade Missions • 2011 Mars Scout – NASA has selected two aeronomy 2 nd Decade Missions • 2011 Mars Scout – NASA has selected two aeronomy science orbiters for further study; downselect in late ‘ 07 – Per AO, selected mission will carry single-string Electra payload and serve as additional Mars relay asset after completion of orbiter’s primary science mission • 2013 Mars Science Orbiter (MSO) – Long-lived core strategic science orbiter w/ relay capability • 10 -yr design lifetime; redundant Electra relay payload • Orbit driven by science objectives (at least for primary science phase) – Science TBD based on ‘ 07 Science Definition Team • 2016/2018 Mission Candidates – Astrobiology Field Laboratory • Baseline ops concept based on MSL – Network Landers • Four or more small static landers (a la previous Netlander concept) Mars Bo. F - CCSDS Jan 2007 Meeting - Colorado Springs 6 18 Jan 2007

Current Proximity Link Baseline (MRO) Forward Link Forward link • Send a file(s) containing Current Proximity Link Baseline (MRO) Forward Link Forward link • Send a file(s) containing the stream of bits to be received by the lander to MRO - MRO can store & forward up to 10 files • MRO uses Prox-1 reliable bit-stream to delivery file contents Mars Bo. F - CCSDS Jan 2007 Meeting - Colorado Springs 7 18 Jan 2007

Current Prox Link Baseline (MRO) Return Link • Accept stream of bits from lander Current Prox Link Baseline (MRO) Return Link • Accept stream of bits from lander using Prox-1 reliable bitstream – Encapsulates the received data into a series of CFDP PDUs which are stored on-board. – The data are reliably transferred to JPL for file processing – At JPL, the CFDP PDUs are processed into the file of received bits from the lander for the identified pass. This file is transferred to the User’s POCC. Mars Bo. F - CCSDS Jan 2007 Meeting - Colorado Springs 8 18 Jan 2007

Proposed Electra Prox-1 Upgrades NOTE: No NASA missions have expressed requirements for changes. 1. Proposed Electra Prox-1 Upgrades NOTE: No NASA missions have expressed requirements for changes. 1. Provide Packet Service – – – 2. Transmit/Receive Packets (Enables messaging) Anticipate Need for Interoperability with ESA Exo. Mars Rovers Packet Service requires variable length frames (to encapsulate packets) • Requires modification to Electra Transmitter; Receiver handles now If Packet Service is added, multiple Port-IDs required – CCSDS already defines Well-defined Port-IDs: • • 3. 0 = Bit Stream 1 = H/W Commands (FWD Link Only) 2 = Packets 3. . 7 = Currently Unassigned Segment/Re-assemble Packets – Helps Electra control frame size (to balance Forward and Return Frame rates) • – Useful to handle unbalanced link conditions Allows users to send packets > 2043 bytes Mars Bo. F - CCSDS Jan 2007 Meeting - Colorado Springs 9 18 Jan 2007

Future Comm capabilities enabled by CFDP and Prox-1 • Prox-1 Message Transfer – Designate Future Comm capabilities enabled by CFDP and Prox-1 • Prox-1 Message Transfer – Designate a port ID for transferring status/control messages between vehicle controllers over proximity link (data for consumption around Mars) – Requires Packet Service on both ends of the I/F – Requires implementation of Multiple port IDs • Some ports consumed in local Mars Environment • Data over other ports for consumption on Earth • Individual File transfer and data management – Current baseline (MRO) is pass file transfer using unacknowledged CFDP/transfer frame retransmission – Data collected by MRO is collected and managed as one pass file – Mars Enterprise defined CFDP metadata and orbiter data manager enables • Individual file prioritization • Increased file accountability (including the orbiter) • Increased ability to manage E 2 E data latency Mars Bo. F - CCSDS Jan 2007 Meeting - Colorado Springs 10 18 Jan 2007

Some Key Issues – – – – – Electra baseline is a bit stream, Some Key Issues – – – – – Electra baseline is a bit stream, but ESA requires packet interface. If packet service is used, do we need global APID management scheme or rely upon other mechanisms such as CFDP – one CFDP APID and use CFDP file names? Use of defined international hailing frequency for hailing. What about working channel assignments? What kind of frequency use therefore bandwidth does Exomars plan on? Need for future Modulations? Coding? NASA/ESA Compatibility with the existing Prox-1 std? End to End accountability and traceability – on frame, packet, product basis Use of CFDP ? Security ? What needs to be put in place in order to exchange command telemetry data operationally for ESA/NASA missions – going beyond the MER/MEX demos? Mars Bo. F - CCSDS Jan 2007 Meeting - Colorado Springs 11 18 Jan 2007