CALIPSO Commissioning Status

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CALIPSO Commissioning Status
Carl Weimer, Lyle Ruppert, Justin Spelman Ball
Aerospace Technologies Corp.
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CALIPSO Satellite is Operational On-Orbit
CALIOP Lidar First Light
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Wide Field Camera
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(No Transcript)
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On-Orbit Program Structure

• Principal Investigator is Dave Winker PI, co-PIs
  Jacque Pelon and Patrick McCormick Payload
  Project Manager Kevin Brown
• Satellite Operation Command Center (SOCC) is
  operated by CNES out of Toulouse
• Mission Operation Command Center (MOCC) is
  operated by NASA LaRC out of VA
• Ball is a partner for Payload operations
• ASDC handling science data is at LaRC
• Calibration/Validation Campaign coordinated out
  of Hampton University
• Includes a Quid Pro Quo sharing of data between
  different ground and airborne systems with
  CALIPSO program
• NASA LaRC has started flying its airborne High
  Spectral Resolution Lidar for validation studies

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Commissioning Progress on Platform

• Alcatel Proteus Spacecraft is fully operational
• Survival Heaters functioning properly to protect
  Payload
• Lithium Batteries are performing well (new to
  LEO)
• S-Band communication system for Command and
  Telemetry is functional (Kiruna)
• Hydrazine Propulsion system is functional and has
  been used
• Power System is nominal Currently 34 V to 36 V
  over an orbit solar array mechanisms nominal
• Nadir Pointing control held to required 0.08
  degrees, achieving 600 m control on ground.
• Orbit Corrections complete, CALIPSO is in the
  A-Train as of May 31
• Gyro Calibration Complete Series of off-nadir
  rotations made, science data was collected to
  study ocean lidar return
• GPS and Attitude (from Startrackers) Bulletins
  being provided to Payload for data geolocation
• Spacecraft commissioning is complete

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Commissioning Progress on Payload

• Ball/NASA Payload is fully operational
• Baseline plan of 45 days was met. Included
  extended period of outgassing and being powered
  off for spacecraft health checks and orbit
  correction maneuvers
• Sequential approach was used to bring up each
  subsystem and verify its functionality
• All subsystems powered up properly, power use
  agrees with predictions for each with minor
  variances
• Thermal performance of subsystems has agreed well
  with pre-launch models.
• Good thermal stability can be achieved within a
  day of powering off/on. Safe to Data Acquisition
  in 3 orbits.
• Laser thermal balancing completed on June 9

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Different Views of Payload
Wide Field Camera BATC CT-633
X-Band Antenna
Sun Shade
Star Tracker Assembly - French
X-Band Transmitter
Payload Controller
Laser Electronics Unit - Fibertek
Imaging Infrared Radiometer -Sodern
Integrated Lidar Transmitter - Fibertek lasers
Lidar Receiver Electronics
Receiver Power Supply
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Lidar Core Transmitter and Receiver
Adjustable Boresight Mechanism
APD
PMTs - LaRC
Laser Radiator
Optical Bench
Laser Optics Modules
Telescope
Beam Expander Optics
ILT (Integrated Lidar Transmitter)
ILR (Integrated Lidar Receiver)
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Lidar Transmitter

• Two redundant NdYAG lasers each capable of full
  mission life
• 110mJ at both 532nm and 1063 nm _at_ 20 Hz
• Lasers were delivered by Fibertek in 2002. Total
  of 80 million shots (4 of mission) fired during
  IT
• Laser has been operational since May 23,
• 27 million shots on-orbit as of June 23
• Conductively cooled, thermal performance has been
  excellent slight shift in operating points from
  those on ground indicating subtle thermal effects
• O-ring sealed pressure decay on units
  observable but meeting lifetime requirements
• Following data shows energy stability starting on
  June 9 (last heater adjust) through June 21

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Laser Pulse Energy
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Lidar Receiver - Detectors

• Photomultipliers (Parallel/Perpendicular 532 nm
  ) and Avalanche Photodiode (1064 nm) are healthy
• High Voltage power supplies showing excellent
  stability lt0.1 over an orbit
• Built in Test System (using LEDs) has verified
  sensitivity and timing response
• Signal levels from Rayleigh are slightly higher
  than predicted based on radiometric math models
  of instrument
• Detector noise levels pass requirements (outside
  of South Atlantic Anomaly)
• Background light measurement made in high
  altitude regions is used to remove offset for
  each shot. Agrees with performance on ground.

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Etalon

• 532 nm channel uses an etalon to limit bandwidth
  in order to reduce daytime background light
• Etalon bandwidth is matched to laser linewidth
  0.035 nm 35 pm 37 GHz
• Finesse of 18
• Etalon is a fixed, match-polished sandwich
  style made by Coronado, in a Ball mount.
• Angle tuned and locked into place on bench.
  Temperature tunable over one linewidth on-orbit
• On-orbit performance agrees with ground
  performance for both center wavelength and
  linewidth.
• Uses main 532 nm lidar signal from
  upper-atmosphere to produce a steady signal to
  allow etalon to be tested

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Etalon Spectral Tuning Raw Data
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Lidar Receiver - Data Processing

• Onboard Data Processing of lidar data is
  functioning properly
• Merge and Scale dual ADCs for each channel to
  achieve 23 bit dynamic range
• Remove offsets and baselines (if needed)
• Aligns all range bins then performs vertical
  and horizontal averaging to reduce data volume
• Calculates a reduced data set to downlink on
  S-band
• Attaches all header information on a shot-to-shot
  basis e.g. laser shot energy, pierce point
  lat/long, range to mean sea level, etc.
• Achieves a lidar data compression of a factor of
  25
• Requires high-performance rad-tolerant computer
• First Flight of General Dynamics PC603 running at
  160 MHz utilizing direct memory access and quad
  processors
• Extensive Error Detection and Correction (EDAC)
  Algorithms are keeping up with radiation induced
  upsets, 5/day.
• Memory testing shows no problems due to radiation
  or weak bits

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Lidar Receiver- Science Data Handling

• Lidar Data is merged with the WFC and IIR data
• Science Data
• Stored in a 48 Gbit solid state recorder on
  Payload
• Downlinked to Alaska (backup in Hawaii) over an
  X-band link once per day
• United Space Networks receives and processes
  before shipping to NASA
• Achieving gt99 data throughput on X-band
• 4.8 GByte/ Day delivered to NASA with 24 hour
  latency looking into reducing this.
• NASA ASDC is generating Level 1 with 24 hour
  latency
• Command and Telemetry Data
• Commands uplinked up to 6 times/day during
  commissioning (during normal ops, this has to be
  scheduled)
• Stored on Platform
• Downlinked on S-band to Kiruna
• Delivered to LaRC with latency 30-45 minutes

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Lidar Transmitter/Receiver Alignment

• Active Boresight Mechanism allows the lidar
  overlap function to be adjusted on-orbit
• Goal is to use once to correct for shifts due to
  launch, thermal, humidity, and 1-g effects
• Extensive testing on ground prior to launch
  including two full atmospheric tests
• Adjusts pointing based on main lidar signal
  strength
• On-Orbit - autonomous search algorithm succeeded
  in 4 minutes (requirement lt 24 hours) fine align
  succeeded in 10 minutes (requirement lt 20
  minutes)
• Alignment repeated multiple orbits to verify
  performance results agreed within limits of
  algorithm approximately 7 microrads within
  requirements
• More stability testing may be done later to look
  at different orbit times (different temperature
  gradients)

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Lidar Polarization Testing Preliminary

• Photomultiplier tubes are collecting
  cross-polarized data at 532 nm
• Primary objective is to distinguish water from
  ice clouds
• Required extensive polarization design, testing
  and alignment of full system
• Wedged quartz depolarizer mounted on a mechanism
  can be inserted into beam to calibrate the two
  channels
• Residual instrument polarization effects lt 0.7,
  measured using Clear- Air depolarization from
  stratospheric Rayleigh scattering (25-35 km)
• Depolarizer gain calibration has shown to be good
  to lt 2 independent of scene the lidar is seeing
• Final polarization characterization will be
  reported in future by Chris Hostetler (NASA LaRC)

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Summary

• CALIPSO is up and running and in the science
  assessment phase
• All subsystems are operating nominally
• Design and performance information on CALIPSO is
  available from Ball to support Wind Lidar trades
  and development
• See attached additional Lidar First Light
  images from Dave Winker
• Acknowledgments Thanks for Inputs from
• Dave Winker, Bill Luck, Bill Hunt, Mike
  Cisewski, Dave Rosenbaum, Alan Little, Rob
  DeCoursey, Dave MacDonnell, Ron VerHappen, from
  NASA
• Ryan Melton, Mike Wallner, Jim Leitch, Brian
  Johnson, and Leela Hill from Ball