NexGen NPOESS Wind Observing Sounder: NASA/GSFC IDL Study and Findings Prepared for Mr. Dan Stockton, Program Executive Officer Program Executive Office

NexGenNPOESS Wind Observing Sounder: NASA/GSFC IDL Study and Findings

Prepared for

Mr. Dan Stockton, Program Executive OfficerProgram Executive Office for Environmental Satellites

Presented by

Dr. Wayman BakerNOAA/NASA/DoD Joint Center for Satellite Data Assimilation

and

Mr. Bruce GentryNASA/GSFC/Laboratory for Atmospheres

Working Group for Space Based Wind Lidar

Wintergreen, VA

2

Background Why Measure Global Winds from Space? Wind Lidar Societal Benefits NOAA Programs Requiring Atmospheric Winds Space-based Wind Lidar Roadmap GWOS/NWOS Comparisons with ADM Aeolus Instrument Development Laboratory (IDL) Study for a

NexGen NPOESS Wind Observing Sounder (NWOS) Concluding Remarks Next Steps/Recommendations

Overview

3

Background ESA planning to launch first DWL in 2009: Atmospheric Dynamics Mission (ADM) - Only has a single perspective view of the target sample volume - Only measures line-of-sight (LOS) winds A joint NASA/NOAA/DoD global wind mission offers the best opportunity for the U.S. to demonstrate a wind lidar in space in the coming decade - Measures profiles of the horizontal vector wind for the first time NASA and NOAA briefings given to:

- USAF (March 20, 2007); letter sent from AF Director of Weather on August 1, 2007 to NASA HQ stating:

- Of the 15 missions recommended by the NRC, global tropospheric wind measurements was most important for the USAF mission

- Willingness to endorse Space Experiments Review Board support via the DoD Space Test Program

- USAF Space Command (May 8, 2007)- Army (May 10, 2007)- NOAA Observing Systems Council (NOSC – June 8, 2007; June 18, 2008) - Navy (June 11, 2007); supporting letter sent on August 8, 2007- Joint Planning and Development Office and FAA (June 18, 2007)- FAA (May 16, 2008)- NOAA Research Council (May 19, 2008)

4

Background (Cont.)

The National Research Council (NRC) Decadal Survey report recommended a global wind mission

The NRC Weather Panel determined that a hybrid Doppler Wind Lidar (DWL) in low Earth orbitcould make a transformational impact onglobal tropospheric wind analyses.

“Wind profiles at all levels” is listed as the #1 priority in the strategic plan for United States Integrated Earth Observing System (USIEOS).

Cost benefit studies have identified economic benefits >$800M/year with the measurement of global wind profiles from space1,2

1 Cordes, J. (1995), “ Economic Benefits and Costs of Developing and Deploying a Space-Based Wind Lidar,

Dept of Economics, George Washington University, D-9502.

2 Miller, K. (2007), “Societal Benefits of Winds Mission,” Lidar Working Group, http://space.hsv.usra.edu/LWG/Index.html

5

Why Measure Global Windsfrom Space ?

The Numerical Weather Prediction (NWP) community

unanimously identifies global wind profiles as the

most important missing observations.

Independent modeling studies at NCEP, ESRL,

AOML, NASA and ECMWF have consistently shown

tropospheric wind profiles to be the single most

beneficial measurement now absent from the

Global Observing System.

6

Why Wind Lidar?Societal Benefits at a Glance…

Improved Operational Weather Forecasts

Civilian Military

Hurricane Track Forecast Ground, Air & Sea OperationsFlight Planning Satellite LaunchesAir Quality Forecast Weapons DeliveryHomeland Security Dispersion Forecasts forEnergy Demands & Nuclear, Biological, Risk Assessment & Chemical ReleaseAgriculture Aerial RefuelingTransportationRecreation

* K. Miller, “Societal Benefits of Winds Mission,” Lidar Working Group Meeting, February 8, 2007, Miami FL, http://space.hsv.usra.edu/LWG/Index.html

** AF aviation fuel usage estimate provided by Col. M. Babcock

• Estimated potential benefits greater than $800M per year*• Including military aviation fuel savings greater than $100 M/year**

7

NOAA ProgramsRequiring Atmospheric Winds*

* Data provided by TPIO / CORL Team

GOAL Program Priority 1 Priority 2 Totals

Climate (CL) Climate Observations & Modeling (COM) 1 1

Commerce & Transportation

(C&T)

Aviation Weather (AWX) 4 4

Marine Weather (MWX) 1 1

Surface Weather (SWX) 2 2

Weather & Water (W&W)

Mission Support (MS)

Air Quality (AQL) 1 1

Hydrology (HYD) 1 1

Local Forecasts & Warnings (LFW) 3 1 4

Modeling and Observing Infrastructure (MOBI)/Environmental Modeling (EMP)

1 1

Total: 4 Goals 8 PROGRAMS 13 2 15

NexGen Hybrid Doppler Wind Lidar - NWOS

NPOESS Wind Observing System For Vertical Wind Profiles

• 3D Tropospheric Winds mission called “transformational” and ranked #1 by Weather panel. 3D Winds also prioritized by Water Cycle panel.

“The Panel strongly recommends an aggressive program early on to address the high-risk components of the instrument package, and then design, build, aircraft-test, and ultimately conduct space-based flights of a prototype Hybrid Doppler Wind Lidar (HDWL).” “The Panel recommends a phased development of the HDWL mission with the following approach:

– Stage 1: Design, develop and demonstrate a prototype HDWL system capable of global wind measurements to meet demonstration requirements that are somewhat reduced from operational threshold requirements. All of the critical laser, receiver, detector, and control technologies will be tested in the demonstration HDWL mission. Space demonstration of a prototype HDWL in LEO to take place as early as 2016.

– Stage II: Launch of a HDWL system that would meet fully-operational threshold tropospheric wind measurement requirements. It is expected that a fully operational HDWL system could be launched as early as 2022.”

GWOS

NWOS

2007 NAS Decadal SurveyRecommendations for Tropospheric

Winds

GWOS(2016)

Demo 3-D global wind

measurements

Operational 3-D global wind

measurements

NexGenNWOS(2026)

DWL Airborne Campaigns, ADM Simulations, etc.

TODWL(2002 - 2008)

TODWL: Twin Otter Doppler Wind Lidar [CIRPAS NPS/NPOESS IPO]ESA ADM: European Space Agency-Advanced Dynamics Mission (Aeolus) [ESA]GWOS: Global Winds Observing System [NASA/NOAA/DoD]NexGen: NPOESS [2nd] Generation System [PEO/NPOESS]

ADM Aeolus (2010)

Single LOS global wind

measurements

9

GWOS/NWOS Comparisons with ADM Attribute ADM GWOS NWOS

Orbit Altitude 400 400 824

Orbit Inclination 98 98 98

Day/Night Night only Day/Night Day/Night

Components per profile

Single –Model estimated second component

Two components - full horizontal vector

Two components - full horizontal vector

Horizontal Resolution

200 kmbetween single LOS’s

300 kmwith full profile both sides of ground track

300 kmwith full profile both sides of ground track

Vertical Resolution PBL 0.25 – 0.5 kmTroposphere 1 km

PBL 0.25 - 0.5km Tropo 2 – 3 km

PBL 0.25 - 0.5 Tropo 2 – 3 km

Collector Diam. 1.5 m (1x) 0.5 m (4x) 0.7 m (4x)

Instrument Design Laboratory [IDL] Studyfor a

NexGen NPOESS Wind Observing Sounder (NWOS):An Operational follow-on to the

Global Wind Observing Sounder (GWOS)Advanced Mission Concept

Sponsored by

Mr. Dan Stockton, Program Executive OfficerProgram Executive Office for Environmental Satellites

NASA Goddard Space Flight Center—Integrated Design Center11

Integrated Design Laboratory—Capabilities and Services

Capabilities:– Instrument families ranging from telescopes, cameras, geo–chemistry, lidars,

spectrometers, coronographs, etc.– Instrument spectrum support from microwave through gamma ray– LEO, GEO, libration, retrograde, drift away, lunar, deep space, balloon, sounding

rockets and UAV instrument design environments– Non-distributed and/or distributed instrument systems

Services:– End-to-end instrument architecture

concept development– Existing instrument/concept architecture

evaluations – Trade studies and evaluation – Technology, risk, and independent

technical assessments– Requirement refinement and verification– Mass/power budget allocation – Cost estimation

12

GWOS IDL Instrument

GWOS Payload Data

Telescope Modules (4)

GPS

Nadir

Star Tracker

Dimensions 1.5m x 2m x 1.8m

Mass 567 Kg

Power 1,500 W

Data Rate 4 Mbps

GWOS in Delta 2320-10 Fairing

Dimensions (mm)

• Orbit: 400 km, circ, sun-sync, 6am – 6pm• Selectively Redundant Design• +/- 16 arcsec pointing knowledge (post-processed)• X-band data downlink (150 Mbps); S-band TT&C• Total Daily Data Volume 517 Gbits

The coherent subsystem provides very accurate (<1.5m/s) observations when sufficient aerosols (and clouds) exist.

The direct detection (molecular) subsystem provides observations meeting the threshold requirements above 2km, clouds permitting.

When both sample the same volume, the most accurate observation is chosen for assimilation.

The combination of direct and coherent detection yields higher data utility than either system alone.

Hybrid DWL Technology Solution

13

Hybrid DWLTechnology Maturity

Roadmap

GWOS

2 micron laser 1988

Autonomous Aircraft Oper

WB-57

Aircraft Operation DC-8

Compact Packaging

2005

Space Qualified

Pre-Launch Validation

Packaged Lidar Ground Demo. 2007

Conductive Cooling

Techn. 1999

Operational NexGen NPOESS

Autonomous Oper. Technol.2008 (Direct)

Space Qualif.

Pre-Launch Validation

2-Micron Coherent Doppler Lidar

Laser Risk Reduction Program

IIP-2004 Projects

Past Funding

Diode Pump Technology

1993

Inj. Seeding Technology

1996

Autonomous Oper. Technol. Coh.

1 micron laser

Compact Laser

Packaging 2007

Compact Molecular

Doppler Receiver 2007

Conductive Cooling Techn.

Diode Pump Technology

Inj. Seeding Technology

High Energy Technology

1997

High Energy Laser

Technology

Lifetime Validation

Lifetime Validation

0.355-Micron Direct Doppler Lidar

TRL 6 to TRL 7

2014 - 2016

2026

TRL 7 to TRL 9

2011 - 20132008 - 2012

TRL 5

ROSES-2007 Projects

NWOS IDL Study User Team

15

Key Findings

The NWOS IDL designs which follow have shown that the Hybrid Doppler Wind Lidar can be operated at a reasonable electrical power and with reasonable reliability for the 5-year mission on board the NPOESS second generation satellite, NexGen.

There are no tall poles in any of the technical developments needed in the future to develop an NWOS.

Because the proof-of-concept GWOS flight is in advance of the NWOS, there should be good opportunity to verify the assumed requirements.

NWOS IDL Study Summary Study Objectives

Study the feasibility of modifying the original IDL design for GWOS at 400 km altitude to work at an 824km altitude on an NPOESS platform

Consider 3 instrument configurations in a trade space that trades telescope aperture, laser duty cycle, pulse power/repetition rate

Examine impact of new technologies, estimate improvements in laser performance, identify technology tall poles.

Minimize power, volume, and mass, as much as possible (in that order)

Consider redundancy for a multi-year lifetime

Key Study Assumptions

824 km, sun-synchronous, dawn-dusk, 1730 ascending node local time, 98.7 deg. Inclination orbit.

5 yr life, 85% reliability goal

2/1 backup lasers direct/coherent

1/0 backup laser electronics direct/coherent

1 backup receiver for each (direct & coherent)

Both coherent and direct lidars either 100% duty cycle (Configurations 1 & 3) or

50% duty cycle (Configuration 2)

Used 10-year beyond 2008 projections for laser efficiencies:x 2 (direct), x 2.25 (coherent)

Either 4 fixed telescopes (Configurations 1 & 2) or 1 holographic element

(Configuration 3)

I n t e g r a t e d D e s i g n C a p a b i l i t y / I n s t r u m e n t D e s i g n L a b o r a t o r y

Aerosol ()

DOP

Preliminary Instrument Design ResultsNexGen Hybrid Doppler Wind Lidar -

NWOSNPOESS Wind Observing System For Vertical Wind

ProfilesDesign Study Objectives

• Study the feasibility of modifying the original ISAL design for GWOS at 400 km to work at an 824km altitude on an NPOESS platform

• Consider 3 instrument configurations in a trade space that tweaks telescope aperture, direct laser duty cycle, and direct laser pulse power/rep rate

– Create multiple mechanical, thermal, and optical models

– Each discipline engineer consider the impacts of all 3 configurations to their subsystems

• Minimize power, volume, and mass, as much as possible (in that order)

• Consider redundancy for a 5 year lifetime

DOPPLER RECEIVER:Multiple Choices

drive science/technology trades• Coherent ‘heterodyne’ (e.g. SPARCLE-NASA/LaRC) • Direct detection “Double Edge” (e.g. Zephyr-NASA/GSFC)• Direct detection “Fringe Imaging” (e.g. Michigan Aerospace)

Molecular ()

Backscattered Spectrum

Frequency

Lidar BackscatterFrom Aerosols & Molecules

NWOS Wind Measurement Concept

Requirements

• Spacecraft accommodations for NWOS: (IDL Study Starting Assumptions)

– Mass - 650 kg – Power - 1000 W – Dimensions in cm (X, Y, Z) - (170,

170, 170)– Data Rates - 10 Mbps – On-orbit life - 5 years– NWOS Location – Nadir deck

• Orbital Altitude: 824km

• Ascending Node: 1730 local (Sun-synchronous dawn-dusk orbit)

• Orbital inclination: ~98.7o

• Orbital period: ~101minutes, 14 orbits/day

These requirements held for all configurations under

consideration.

NPOESS NexGen



ProfilesI n t e g r a t e d D e s i g n C a p a b i l i t y / I n s t r u m e n t D e s i g n L a b o r a t o r y

Configuration 1 and 2(Inverted GWOS)

Configuration 3(ShADOE)

NWOS HDWL Instrument Configurations

NPOESS LAN 1730 S/C Sensor Configuration

= Space Considered for NWOS

4.5 m

5.7 m

3.75 m dia.

Launch Concept for the Atlas 5 - 4 m Diameter Fairing

NPOESS 1730 LAN Spacecraft

Configuration #1

Configuration #2 Configuration #3

Optical Design

Shared, Inverted GWOS,4

azimuths 100 % Duty Cycle

Shared, Inverted

GWOS,4azimuths 50 % Duty

Cycle

Common Aperture,ShADOE,4 azimuths

100 % Duty Cycle

Mass [kg] 595 595 661

Telescope Module Dimensions(ht x dia)

100x160cm 100x160cm 127x160

Structural Assem.

Dimensions72.5 x 170 x 170cm

Telescope Primary Diameter

0.7m (0.5m

Coherent)

0.7m (0.5m Coherent)

1.24m (0.72m

Coherent)

Orbital Avg Power [W] 1382 898 1382

Peak Power [W]

1382

1382

1382Standby Power [W] 719

Warmup Power [W] 861

NWOS HDWL Instrument Trade Summary

No contingency added (+30%)

Configuration #1

Configuration #2

Configuration #3

Direct Laser - Number of Sources - Rep. Rate - Pulse energy - FOV - Detector

355nm3100 Hz 0.9 – 1J @1064nm<100uradEMCCD array



Coherent Laser - Number of Sources - Rep Rate - Pulse energy - FOV - Detector

2microns25 Hz1.2 JDiffraction LimitedInGaAs photodiode



On-board Computational Requirements

RAD6000 Processor @ 3.9Mbs

Vibrational Modes Gen.

Fidelity of structural model not high enough to predict

Unique S/Interface IEEE 1394A



Profiles

NWOS HDWL Instrument Parameters

I n t e g r a t e d D e s i g n C a p a b i l i t y / I n s t r u m e n t D e s i g n L a b o r a t o r y

4.5 m

5.7 m

3.75 m dia.





NWOS HDWL Instrument Configurations

Configuration #1


Optical Design

Shared, Inverted GWOS,4

azimuths 100 % Duty Cycle

Shared, Inverted

GWOS,4azimuths 50 % Duty

Cycle

Common Aperture,ShADOE,4 azimuths

100 % Duty Cycle

Mass [kg] 595 595 661

Telescope Module Dimensions(ht x dia)

100x160cm 100x160cm 127x160

Structural Assem.

Dimensions72.5 x 170 x 170cm


0.7m (0.5m

Coherent)

0.7m (0.5m Coherent)

1.24m (0.72m

Coherent)

Orbital Avg Power [W] 1382 898 1382

Peak Power [W]

1382

1382



NWOS HDWL Instrument Trade Summary

No contingency added (+30%)

19

The NWOS IDL design study has shown that the Hybrid Doppler Wind Lidar can be operated at a reasonable electrical power and with reasonable reliability for the 5-year mission on board the NPOESS second generation satellite.

There are no tall poles that depend on unforeseen technical developments in the future.

Because the proof-of-concept GWOS flight is in advance of the NWOS, there should be good opportunity to verify the assumed requirements.

NWOS IDL Study Conclusions

Return

2020

NPOESS evaluation of ADM data

Participate on ESA’s ADM Aeolus Team [Launch 2009] to help establish good data/products and to enable

Aeolus data gathering/usage for NWOS studies

Perform study investigating the utility / impact of NWOS data for NexGen using Aeolus data as proxy data and the NWOS projected capabilities from the previous ADM potential impact studies

NWOS concept development

Estimate NWOS Instrument Cost - use NWOS detailed Parts List developed from IDL NWOS Study

Perform mission conceptual design study - NWOS Study User Team & GSFC MDL (Mission Design Laboratory)

Next Steps/Recommendations

21

Supporting Material

22

Observations Needed as a Function of Forecast Length

Return

23

Which Upper Air ObservationsDo We Need ?

Numerical weather prediction requires independent observations of the mass (temperature) and wind fields

The global three-dimensional mass field is well observed from space

No existing space-based observing system provides vertically resolved wind information => horizontal coverage of wind profiles is sparse

24

Current Mass & Wind Data Coverage

Upper AirMass Observations

Upper AirWind Observations

25

Mean (29 cases) 96 h 500 hPa height forecast error difference (Lidar Exper minus Control Exper) for 15 - 28 November 2003 with actual airborne DWL data. The green shading means a reduction in the error with the Lidar data compared to the Control.

The forecast impact test was performed with the ECMWF global model.

DWL measurements reduced the 72-hour forecast error by ~3.5% This amount is ~10% of that realized at the oper. NWP centers worldwide in the past 10 years from all the improvements in modelling, observing systems, and computing power Total information content of the lidar winds was 3 times higher than for dropsondes

Forecast ImpactUsing Actual Aircraft Lidar Winds

in ECMWF Global Model(Weissmann and Cardinali, 2007)

Green denotes positive impact

26

Airborne Doppler Wind LidarsIn T-PARC/TCS-08 Experiment

in Western North Pacific Ocean (2008) to investigate tropical cyclone formation, intensification, structure change and satellite validation

ONR-funded P3DWL (1.6 um coherent) PI is Emmitt (SWA)Will co-fly with NCAR’s ELDORA and dropsondes

Wind profiles with 50 m vertical and 1 km horizontal resolution

Multi-national funded 2 um DWL on DLR Falcon PI is Weissmann (DLR) Will fly with dropsondes

T-PARC: THORPEX Pacific Asian Regional CampaignTCS-08: Tropical Cyclone Study 2008

u,v,w,TAS, T,P,q

Lidar horizontalwind speed

W'

u,vDropsondesu, v ,P, T, q

Data will be used to investigate impact of improved wind data on numerical forecasts

27

Simulated Impactof Space-based Wind Lidar Observations

on a Hurricane Track Forecast (R. Atlas et al.)

Hurricanes TracksGreen: Actual track

Red: Forecast beginning 63 h before landfall with current data

Blue: Improved forecast for same time period with simulated DWL data

Note: A significant positive impact was obtained for both land falling hurricanes in the 1999 data; the average impact for 43 oceanic tropical cyclone verifications was also significantly positive

28

• Reduce preventable property damage ~ $212 M/year 2,3

• Reduce over-warnings ~ $74 M/year 2,3

• 17% less landfall warning error for average of 2 storms/year 1

• Typically warn ~ 350 miles of coast, over-warn 220 miles • Estimate 17% reduction in over-warning with lidar winds, 37 miles• @ $1M / mile precautionary costs saves $37M/storm, $74M/year

Lidar WindsWill Improve Hurricane Forecasts

41 Storm climatology and simulations

for global 3D winds in NWP2 Cordes, J. J., “Economic Benefits

and Costs of Developing and Deploying A Space-Based Wind Lidar,” GWU, NOAA Contract 43AANW400233, March 1995

3 K. Miller, “Societal Benefits of Lidar Winds”, Lidar Working Group,” February 8, 2007

4 www.ncdc.noaa.gov/billionz.html

29

Summary of Benefits Estimates($M/year)*a

* K. Miller, “Societal Benefits of Winds Mission,” Lidar Working Group Meeting, February 8, 2007, Miami FL, http://space.hsv.usra.edu/LWG/Index.html

2006 EstHurricane Overwarning 74Preventable Hurricane Damage 212Off Shore Drilling 39General Forecasting 137Airline Aviation Fuel 243Military Aviation Fuel 101Total 806

I n t e g r a t e d D e s i g n C e n t e r / I n s t r u m e n t D e s i g n L a b o r a t o r y

30

NWOS Study Objective

•Study the feasibility of modifying the original ISAL design for GWOS at 400km to work at an 824km altitude on an NPOESS platform•Consider 3 instrument configurations in a trade space that tweaks telescope aperture, direct laser duty cycle, and direct laser pulse power/rep rate– Create multiple mechanical, thermal, and optical models

– Each discipline engineer consider the impacts of all 3 configurations to their subsystems

•Minimize power, volume, and mass, as much as possible (in that order)•Consider redundancy for a 5 year lifetimeReturn


Doppler Lidar Measurement Concept

DOPPLER RECEIVER - Multiple flavors - Choice drives science/technology trades• Coherent ‘heterodyne’ (e.g. SPARCLE/LaRC) • Direct detection “Double Edge” (e.g. Zephyr/GSFC)• Direct detection “Fringe Imaging” (e.g. Michigan Aerospace)

Molecular ()

Aerosol ()

Backscattered Spectrum

Frequency

DOP

Return

Goddard Space Flight Center 32

NWOS Hybrid Doppler Wind Lidar Measurement Geometry: 824 km

7.4 km/s

824 km1253 km

889 km

626 km

626 km

45

53

45180 ns (27 m) FWHM (76%)

8 m (86%)

1/5 s = 1319 m1/200 s = 33 m

Return light: t+6.6 ms, 62 m, 8.7 microrad

First Aft Shott + 190 s

60/2400 shots = 12 s = 78 km

90° fore/aft anglein horiz. plane

FOREAFT

Second shot: t+200 ms, 5 ms1489 m, 207 microrad37 m, 5.3 microrad

2 lines LOS wind profiles1 line “horiz” wind profiles

45 deg azimuth Doppler shiftfrom S/C velocity ±3.6 GHz ±21 GHz

Max nadir angle tostrike earth62.3 deg

Return


33

NWOS Requirements–Spacecraft and Orbit

• Spacecraft accommodations for NWOS: (starting assumptions)– Mass - 650 kg – Power - 1000 W – Dimensions in cm (X, Y, Z) - (170,

170, 170) cm – Data Rates - 10 Mbps – On-orbit life - 5 years– NWOS Location – Nadir deck– Reliability Goal – 85%

• Orbital Altitude: 824km• Ascending Node: 1730 local

(Sun-synchronous dawn-dusk orbit)

• Orbital inclination: ~98.7o

• Orbital period: ~101minutes, 14 orbits/day

These requirements hold for all configurations under

consideration.

Courtesy D. Evans

From GWOS Systems

Return


34

NWOS System Configurations(Courtesy M.Clark and D.Palace)



Return


35

NPOESS LAN 1730 S/C Sensor Configuration

= Space Considered for NWOSReturn


36

3.75 m dia.

4.5 m

5.7 m



Return


37

NWOS System Description (1 of 2)

Configuration #1 Configuration #2 Configuration #3

Optical DesignShared, Inverted GWOS,4 azimuths100 % Duty Cycle

Shared, Inverted GWOS,4 azimuths100 % Duty Cycle

Common aperture, ShADOE, 4 azimuths100 % Duty Cycle

Mass [kg] 595 595 661

Telescope Module Dimensions

(height x diameter)100x160cm 100x160cm 127x160

Structural Assembly Dimensions 72.5 x 170 x 170cm


0.7m

(0.5m Coherent)

0.7m

(0.5m Coherent)

1.24m

(0.72m Coherent)

Orbital Average Power [W] 1382 898 1382

Peak Power [W]

1382

1382



* No contingency added (+30%)

Return


38

NWOS System Description (2 of 2)

Configuration #1


Direct Laser

- Number of Sources

- Rep. Rate

- Pulse energy

- FOV

- Detector

355nm

3

100 Hz

0.9 – 1J @1064nm

<100urad

EMCCD array

355nm

3

100 Hz

0.9 – 1J @1064nm

<100urad

EMCCD array

355nm

3

100 Hz

0.9 – 1J @1064nm

<100urad

EMCCD array

Coherent Laser

- Number of Sources

- Rep Rate

- Pulse energy

- FOV

- Detector

2microns

2

5 Hz

1.2 J

Diffraction Limited

InGaAs photodiode

2microns

2

5 Hz

1.2 J

Diffraction Limited

InGaAs photodiode

2microns

2

5 Hz

1.2 J

Diffraction Limited

InGaAs photodiode

On-board Computational Requirements RAD6000 Processor @ 3.9Mbs

Vibrational Modes Generated

Fidelity of structural model not high enough to predict

Unique Spacecraft Interface IEEE 1394A

Return

Documents

NexGen NPOESS Wind Observing Sounder: NASA/GSFC IDL Study and Findings Prepared for Mr. Dan Stockton, Program Executive Officer Program Executive Office