1 calipso lidar working group 18jul02 cloud-aerosol lidar and infrared pathfinder satellite...

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CALIPSCALIPSOO

Lidar Working Group18Jul02

Cloud-Aerosol Lidar and Infrared Pathfinder Satellite Observations

Space-Qualified Hardware for the CALIPSO Lidar

Ron Schwiesow Ball Aerospace and Technologies Corp.

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2Lidar Working Group18Jul02


CALIPSO is a pathfinder for the GTWS mission

Flight-qualified Nd:YAG lasers demonstrated to 2109 pulses

Laser beam expanders with anti-feedback provision

1-m beryllium telescope (OCA/Corning) Flight-qualified PMT and APD detectors with

associated preamps High-speed digitizer Powerful, flight-qualified computer with fault

tolerance (General Dynamics PowerPC™ 603R) Auxiliary instruments for context imaging

(Wide-field Camera and Imaging Infrared Radiometer)

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The payload includes 3 instruments

Telescope Sunshade

Integrated Lidar Transmitter

Wide Field Camera

Star Tracker Assembly X-Band Antenna

Imaging InfraredRadiometer

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The payload includes 3 instruments

Platform Electrical Interface Bracket

Payload Controller

Star Tracker Assembly

Lidar Receiver Electronics

X-Band Transmitter

Laser Electronics Unit

Receiver Power Supply

Wide Field Camera

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Monolithic optical bench supports the lidar

ILT (Integrated Lidar Transmitter)

ILR (Integrated Lidar Receiver)

Lidar Instrument Core

Beam Expander

Optics

Active Boresight

Mechanism

Laser Optics

Modules

Laser Radiator

PMTs

Telescope

Optical Bench

APD

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Risk-reduction laser proved concept

2109 pulses demonstrated

validated contamination-control procedures

verified KTP doubler operation

established misalignment tolerance

showed benefits of derated components

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Laser optics modules are tested and delivered

Flight Laser #2 Prior to Lid Closure Flight Laser #1 in Sealed Canister

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Laser burn-in is part of the qualification process

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Beam-expander optics are delivered and tested

All-reflective design Mounts to laser

optics module Beam expansion

13x f/1.4 primary mirror >0.98 reflectivity at

532 and 1064 nm

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Laser vibration test is done with mass model of beam expander

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Laser functional test verifies performance

110 mJ each wavelength

20.25-Hz PRF 25-pm linewidth

at 532 nm 6-8 mm-mrad

beam quality polarization

purity 3700:1

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All-beryllium telescope has fast primary and f/4.7 secondary

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Tested telescope assembly has been delivered from vendor

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First fold mirror assembly includes field stop and flexure mounts

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Refractive collimator and flexure mounts tested as a subassembly

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Dichroics, mirrors, and polarizing beamsplitter tested separately

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Sandwich etalon filter for 532 nm provides good optical performance

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Sandwich etalon passed thermal and mechanical qualification

Housing provides thermal stabilization and uniformity

Etalon polished to approximate wavelength, angle-tuned to precise wavelength, thermal tuned to track changes

Bandpass 42 pm Peak transmission >0.81 Contrast ratio >160 Birefringence <0.001 crosstalk

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Flight APD includes preamp and stabilization circuitry

Based on MOLA design

QE 0.40 Noise

0.004 pW Hz-½

Bandwidth 4 MHz

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Cabling mockup prepares for final integration and test

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Structures include optics bench, sunshade, and housing

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Composite structure is assembled for testing

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The composite structure is qualified with mass models in place

Structure includes sunshade

Components mounted to outside of payload housing

Optical bench floats inside housing

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Optical bench is a monolithic composite structure

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Optical bench is also tested with mass models of components

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Wide-field camera is based on standard CT-633 star tracker

Flt Lens Assembly

–Longer lens, narrower FOV than CT-633

–Neutral density filter with full aperture

–Bandpass filter 620 - 670 nm

–512x512 CCD as push-broom scanner

–RS-422 synchronous serial I/O

Standard CT-633

Flight PWAs

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Imaging infrared radiometer is developed by SODERN

Housing Structure Eng Model

Mirror Mechanism EM

Flight Infrared Sensor Module (IASI)

Based on Boeing microbolometer arrays

Mirror for 2-point calibration

6464 snapshot array

3 spectral channels sequential

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Payload Simulator

Allows testing of interface to spacecraft platform

Currently in service at Alcatel in France

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Launch planned for April04

Dual launch with CloudSat on dual launch adapter fitting

Delta II 7420 launch vehicle 3-m standard fairing

1 calipso lidar working group 18jul02 cloud-aerosol lidar and infrared pathfinder satellite...

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