1

International EOS/NPP International EOS/NPP Direct Readout MeetingDirect Readout Meeting

October 2005October 2005

National Polar-orbiting Operational National Polar-orbiting Operational Environmental Satellite SystemEnvironmental Satellite System

(NPOESS)(NPOESS)Direct Readout MissionDirect Readout Mission

2

Direct Readout Lab Roadmap to NPP and Beyond

3

DMSP (Defense Meteorological

Satellite Program)

EOS (Earth Observing

System)

NPOESS (National Polar-orbiting

Operational Environmental Satellite System)

Sensor data rate: 1.5 MbpsData latency: 100-150 min.

1.7 GigaBytes per day (DMSP)6.3 GigaBytes per day (POES)

15 Mbps sensor data rateData latency: 100-180 min.Data availability: 98%Ground revisit time: 12 hrs.

2.6 TeraBytes per day (EOS)2.4 TeraBytes per day (NPP)

20 Mbps sensor data rateData latency: 28 min.Data availability: 99.98%Autonomy capability: 60 daysSelective encryption/deniabilityGround revisit time: 4-6 hrs.

8.1 TeraBytes per day

POES (Polar Orbiting

Operational Environmental Satellites)

NPP (NPOESS

Preparatory Project)

1960 - 2010 2000 - 2010 2010 – 2020+

NPOESS Satisfies Evolutionary Program Needs with Enhanced CapabilitiesNPOESS Satisfies Evolutionary Program Needs with Enhanced CapabilitiesNPOESS Satisfies Evolutionary Program Needs with Enhanced CapabilitiesNPOESS Satisfies Evolutionary Program Needs with Enhanced Capabilities

Data Volume Evolution

4

RF Communications Subsystem Overview

LRD• L-band, earth coverage

spacecraft antenna• Channel rate at 7.76 Mbps

HRD• X-band, earth coverage

spacecraft antenna• Channel rate of 40 Mbps

DRR Wideband ground communications

LRD FTS Sites

SafetyNet SMD Downlink• Ka-band, biaxial steerable

spacecraft antenna• High rate mission data and real-

time and/or stored telemetry provided with low latency worldwide

C3S

Svalbard, Norway• Primary T&C

HRD FTS Sites

Command• S-band, omni antenna• Encryption/Authentication Telemetry• S-band, omni antenna

Command and Uploads• S-band, omni antenna• Encryption/Authentication Telemetry• S-band, omni antenna• Both real-time and stored

telemetry channels

TDRS • LEO&A• On-orbit backup

5

Overview Spacecraft Iso-view

S-band Antenna (Zenith)

CMIS Antenna Unit

VIIRS

ADCS Antenna-Tx

ATMS CRIS

SESS HORUS

HRD Antenna

LRD AntennaSARSAT Antenna-Tx

S-band Antenna (Nadir)

TSIS

Altimeter CRIMSS

SARSAT/ADCS Antenna-Rx

NPOESS Spacecraft(1730 Orbit Shown)

6

HRD RF Downlink Characteristics

Parameter Value/CharacteristicsCarrier Frequency 7.834 GHz, nominal

Polarization RHCP

Antenna Axial Ratio < 5 dB (within antenna FOV of + 62 degrees)

Modulation SQPSK

Pulse Shaping Square root raised cosine (SRRC)pulse shaping ( = 0.5)

Channel Data Rate 40 Mbps(Includes all CCSDS, Reed-Solomon and convolutional encoding overhead)

Decoded BER <10-8

Link Availability > 99.6% at worst-location(Using ITU-R P. 618-8 orbit averaging)

7

HRD RF Downlink CharacteristicsCoding/Randomization

Parameter Value/CharacteristicData Format NRZ-M (Prior to convolutional encoding)

Reed-Solomon Coding (255, 223) with Interleave Depth = 4

Convolution Coding:

- Coding Rate (R)

- Constraint Length

- Connection Vectors

- Phase Relationship

- Symbol Inversion

- Number of Encoders

(CCSDS 101.0-B-6)

1/2

7

G1=1111001, G2=1011011

G1 symbol before G2 symbol

G2

1

Data Randomization:- Generator

(CCSDS 101.0-B-6)

h(x)=x8+x7+x5+x3+1

8

HRD EIRP vs. Nadir Angle

6789

10111213141516171819202122232425262728293031

0 5 10 15 20 25 30 35 40 45 50 55 60 65

Nadir Angle (deg)

EIR

P (

dB

Wi)

PFD Limit

RF Comm Subsystem Spec

• Shaped beam antenna compensates for space & rain loss variation (function of ground antenna elevation angle) to provide near constant PFD at surface of Earth

9

HRD Downlink Spectral Mask

-50

-45

-40

-35

-30

-25

-20

-15

-10

-5

0

-107.8 -92.4 -77.0 -61.6 -46.2 -30.8 -15.4 0.0 15.4 30.8 46.2 61.6 77.0 92.4 107.8

Relative Frequency (MHz)

dB

NTIA Mask

SQPSK (Alpha = 0.5, TWTA)

• SRRC pulse shaping provides bandwidth efficient spectral occupancy

10

HRD Long-Term Orbit-Averaged Availability

Orbit-Average availability over any short-term period may be different than long-term average

11

LRD RF Downlink Characteristics

Parameter Value/CharacteristicsCarrier Frequency 1.707 GHz, nominal

Polarization RHCP

Antenna Axial Ratio < 3 dB (within antenna FOV of + 62 degrees)

Modulation SQPSK

Pulse Shaping Square root raised cosine (SRRC)pulse shaping ( = 0.5)

Channel Data Rate 7.76 Mbps(Includes all CCSDS, Reed-Solomon and convolutional encoding overhead)

Decoded BER <10-8

Link Availability > 99.9% at worst-location(Using ITU-R P. 618-8 orbit averaging & exclude ionosphere scintillation)

12

LRD RF Downlink CharacteristicsCoding/Randomization

Parameter Value/CharacteristicData Format NRZ-M (Prior to convolutional encoding)

Reed-Solomon Coding (255, 223) with Interleave Depth = 4

Convolution Coding:

- Coding Rate (R)

- Constraint Length

- Connection Vectors

- Phase Relationship

- Symbol Inversion

- Number of Encoders

(CCSDS 101.0-B-6)

1/2

7

G1=1111001, G2=1011011

G1 symbol before G2 symbol

G2

1

Data Randomization:- Generator

(CCSDS 101.0-B-6)

h(x)=x8+x7+x5+x3+1

13

LRD EIRP vs. Nadir Angle

• Shaped beam antenna compensates for space and rain loss Variation (function of ground antenna elevation angle) to provide near constant PFD at surface of Earth

23456789

10111213141516171819202122

0 5 10 15 20 25 30 35 40 45 50 55 60 65

Nadir Angle (deg)

EIR

P (

dB

Wi)

PFD Limit

RF Comm Subsystem Spec

14

LRD Downlink Spectral Mask

• SRRC pulse shaping provides bandwidth efficient spectral occupancy

-50

-45

-40

-35

-30

-25

-20

-15

-10

-5

0

-23.28 -19.40 -15.52 -11.64 -7.76 -3.88 0.00 3.88 7.76 11.64 15.52 19.40 23.28

Frequency (MHz)

dB

NTIA Mask

SQPSK (Alpha = 0.5, SSPA)

15

LRD Long-Term Orbit-Averaged Availability

Orbit-Average availability over any short-term period may be different than long-term average

16

NPOESS / NPP Sensor Manifest

1330 - NPOESS 1730 - NPOESS 2130 - NPOESS1030 - NPP

VIIRSVIIRS

CMISCMIS

CrISCrIS

ATMSATMS

SESSSESS

SSSS

SARSATSARSAT

ADCSADCS

ERBSERBS

OMPSOMPS

VIIRSVIIRS

CMISCMIS

VIIRSVIIRS

CMISCMIS

SSSS

SARSATSARSAT

ADCSADCS

ALTALT

TSISTSIS

VIIRSVIIRS

CrISCrIS

ATMSATMS

SSSS

CrISCrIS

ATMSATMS

APSAPS

SARSATSARSAT

CERESCERES

OMPSOMPS

SESSSESS SESSSESS

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LRD Data Content Balances Performance and Provides Flexibility

Limited LRD Bandwidth

3.88 Mbps

Programmable LRD downlink Programmable LRD downlink provides flexibility for the futureprovides flexibility for the futureProgrammable LRD downlink Programmable LRD downlink

provides flexibility for the futureprovides flexibility for the future

1330 & 1730 2130

-

500,000

1,000,000

1,500,000

2,000,000

2,500,000

3,000,000

3,500,000

4,000,000

1 2 3 4

VIIRS**

CMIS*

CrIS*

ATMS*

Margin

Ancillary*

ALT

ADCS

DMDM

TOD

Encryption

CCSDS-

500,000

1,000,000

1,500,000

2,000,000

2,500,000

3,000,000

3,500,000

4,000,000

1 2 3 4

CrIS

CMIS

VIIRS

Selection of compression (6:1) applied to selected VIIRS mission data for increased mission data throughput in downlink

-

500,000

1,000,000

1,500,000

2,000,000

2,500,000

3,000,000

3,500,000

4,000,000

1 2 3 4

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Field Terminal Ancillary Data Approach

Dynamic ancillary data contained within LRD and HRD downlinks to meet specified performance levels

Data for six pressure levels from the NWP forecast model - Temperature- Humidity- Surface pressure- Standard pressure levels- Wind speed, wind direction- Precipitable water

For SESS EDR production• Effective sunspot number and global geomagnetic Kp

NPOESS mission support data server, accessible via internet

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Ancillary Data DownlinkGraphical Representations

• 16 points spaced 200 kilometers apart at right angles to the ground track

• Completely covers the area viewed by all sensors

• Successive lines 200 kilometers apart

• Each line transmitted twice to ensure receipt by the ground

Path of the satellite

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21

EDRs with Key Performance Parameters

VIIRSCMISCrIS/ATMSOMPSSESGPSOSERBSTSISALTAPS

2519

31

1325134

NPOESS High Rate Data (HRD)Environmental Data Records (EDRs)

Atm Vertical Moisture ProfileAtm Vertical Temp Profile

Imagery

Sea Surface TemperatureSea Surface Winds

Soil Moisture

Active Fires

Aerosol Particle SizeAerosol Refractive IndexAlbedo (Surface)Auroral BoundaryAuroral Energy DepositionAuroral ImageryCloud Base HeightCloud Cover/LayersCloud Effective Particle SizeCloud Ice Water PathCloud Liquid Water

Cloud Optical ThicknessCloud Particle Size/Distribution

Cloud Top Height

Aerosol Optical Thickness

Cloud Top Pressure

Cloud Top Temperature Downward LW Radiance (Sfc)Downward SW Radiance(Sfc)

Electric FieldElectron Density ProfileEnergetic Ions

Geomagnetic Field Ice Surface TemperatureIn-situ Plasma FluctuationsIn-situ Plasma Temperature

Ionospheric ScintillationMedium Energy Charged ParticlesLand Surface Temperature

Net Heat FluxNet Solar Radiation (TOA)Neutral Density ProfileOcean Color/ChlorophyllOcean Wave CharacteristicsOutgoing LW Radiation (TOA)

Ozone; Total Column/ProfilePrecipitable Water

Precipitation Type/Rate Pressure (Surface/Profile)Sea Ice CharacterizationSea Surface Height/Topo.Snow Cover/DepthSolar Irradiance

Supra-Thermal-Auroral Part.Surface TypeSurface Wind StressSuspended MatterTotal Water ContentVegetation Index

22

EDRs with Key Performance Parameters

VIIRSCMISCrIS/ATMSOMPSSESGPSOSERBSTSISALTAPS

2519

31

1325134

NPOESS Low Rate Data (LRD)Environmental Data Records (EDRs)

Atm Vertical Moisture Profile #3Atm Vertical Temp Profile #2

Imagery #1

Sea Surface Temperature #8Sea Surface Winds #4

Soil Moisture

Active Fires (P)

Aerosol Particle SizeAerosol Refractive IndexAlbedo (Surface)Auroral BoundaryAuroral Energy DepositionAuroral ImageryCloud Base Height #5Cloud Cover/Layers #6Cloud Effective Particle SizeCloud Ice Water Path (P)Cloud Liquid Water

Cloud Optical ThicknessCloud Particle Size/Distribution

Cloud Top Height

Aerosol Optical Thickness

Cloud Top Pressure (P)

Cloud Top Temperature Downward LW Radiance (Sfc)Downward SW Radiance(Sfc)

Electric FieldElectron Density ProfileEnergetic Ions

Geomagnetic Field Ice Surface TemperatureIn-situ Plasma FluctuationsIn-situ Plasma Temperature

Ionospheric ScintillationMedium Energy Charged ParticlesLand Surface Temperature

Net Heat FluxNet Solar Radiation (TOA)Neutral Density ProfileOcean Color/ChlorophyllOcean Wave CharacteristicsOutgoing LW Radiation (TOA)

Ozone; Total Column/ProfilePrecipitable Water

Precipitation Type/Rate Pressure (Surface/Profile) #7Sea Ice CharacterizationSea Surface Height/Topo.Snow Cover/DepthSolar Irradiance

Supra-Thermal-Auroral Part.Surface Type (P)Surface Wind StressSuspended MatterTotal Water ContentVegetation Index (P)

23

Field Terminal Data Flow

Signal Processing Subsystem

Data Processor Element

MissionApplicationSubsystem

Post ProcessingVisualization

Tracking Antenna

LNADownConverter/

FilterReceiver/

DemodulatorBit

SynchronizerViterbi

Decoder

CCSDS Processing

FrameSynchronizer

CADUs

Derandomization

Reed SolomonDecoding

VCDU Processing

Ingest

GranulateHRD/LRD MissionData and MissionSupport DataGenerate RDRs

Data ManagementStore and Retrieve xDRs

Data Delivery

Convert xDRs toHDF5, Deliver toMAS

Infrastructure

Work Flow Management

APs

ProcessingGenerate SDRs, TDRs,EDRs

CVCDUs

VCDUs

AES DecryptionVCDUs

MissionSupport

DataServer

MSD fornetwork

connectedField

Terminals

Downlink FromSpacecraft

24

Direct Readout Interfaces

Field Terminal Segment

Mission Support Data Server (C3S)

• Ancillary Data• Auxiliary Data• TLE

SPE-DPE Interface

Streaming APs

Data Processor Element

• DPE Hardware- Processing- Storage

> Mission Data> Mission Support Data> Static Data

• DPE Software- ING, PRO, INF, DMS, DDS

FT Operator

Mission Application Element

• User-defined HDF Product Display

FT Operator or User

FT-MSDS Interface(Optional)

DPE-MAE Interface

Product requests & HDF files

Satellite Down Link

Field Terminal Data Flow

Optional FT Data Flow

NPOESS Developed

NPOESS Defined

Optional FT Interfaces

FT Interfaces

Satellite - SPE Interface

Legend

NPOESS / NPP SatellitesMission and Ancillary

Data(HRD/LRD Downlink)

Satellite-SPE Interface

Signal Processing Element

• Antenna / RF Processing • GPS and Timing• Satellite Scheduler• CCSDS Processing

- Mission Data- Mission Support Data- Satellite Pass Storage- TLE Extraction

• Decryption

FT Operator

25

Field Terminal Data Processor Element Software Design

•Open Systems Group standards compliance at interfaces minimizes configurations

•Programmable LRD downlink favors 8 Priority EDRs

•Onboard VIIRS data compression rates by APID for LRD

•Flexible ancillary data approach • Dynamic ancillary data via satellite downlink • NPOESS Mission Support Data Server via Internet access

26

FTS EDR Performance

HRD EDR performance• 99% of performance attributes meet or exceed performance

thresholds• Latency requirements achievable with current COTS multiple

CPU workstations • Designed to recognize missing channels and ancillary data• Lossless RICE compression on VIIRS

LRD EDR performance• 0.8 km resolution imagery and programmable downlink• Produces 8 high priority EDRs at or near LRD objective levels• Produces 15 lower priority EDRs and required predecessor

EDRs• Designed to recognize missing channels and ancillary data• Lossless and Lossy JPEG2000 compression on selected APIDs

27

FTS Latency Analysis for Stress-case

• FTS Latency Requirement: max latency is 15 minutes. • SYS013235 & SYS013230 - Field Terminal software, when installed on NPOESS-

specified HRD field terminal hardware, shall produce the Imagery EDR in less than or equal to 2 minutes and all other EDRs as specified in Appendix E in less than or equal to 15 minutes after receipt of data from the FT Signal Processing Subsystem.

• A large number of factors impact FTS processing. • Terrain - Land or ocean• Day versus Night sensor characteristics• Weather - Cloudy, Partial Cloudy, Clear• Satellite Orbits & FTS emplacement (Latitudes)• FTS Hardware: CPUs (3 GHz NPP era)

28

FTS Simulation (e.g. 45N/00):1 day 15 Passes with 3 NPOESS S/C

1330 1730 2130

FTS Contacts with NPOESS S/C

(1440 minutes = 1 days)

Contact Durations:Max 13.1 minsAvg 10.5 minsMin 2 mins<4mins 2.3%

Back-to-back contacts

29

Overlapping S/C contacts don’t occur due to spacecraft orbital phasing.

Smallest gap of 10.2 minutes has minimal impact to FTS latency.

Above 60N there is a large increase in contacts and EDRs.

Back-to-back S/C Contacts

Max gap is 2.1 orbits at equator

Gap Time Between Contacts

Analyzed STK 1330/1730/2130 contact data

60N

30

Orbital Position Defines Dynamic Scene Content in Sensor Data

Orbital Position defines Sensor Nadir NCEP Weather Data Base

Scene in VIIRS View

Ocean

Cloudy

Snow/Ice

Dynamic Processing

31

Land/Ocean, Day/Night, and Clear/Cloudy Data

Land has process loads comparable to ocean.

Day data is 4x night data processing. Day-only algorithms are: • ACO/OCC • Vegetation Index • Surface Types• Aerosols (large load)• Surface Albedo (large load)

Clear Data is most stressing Clear-only algorithms are: • ACO/OCC • Vegetation Index • Land/Ice Surface & Sea Surface Temp• Surface Types• Aerosols (large load)• Surface Albedo (large load)• CMIS/CrIS AVT/MP (large load)

Used Land, Day and 100% Clear data

Day

Night

EDR Processing

EDR Processing

32

FTS Latency StatusAll EDRs & Imagery EDR

Comparison of 2.6 GHz and 5.0 GHz HRD Results

HRD - Full NPOESS EDR Set - 100% Level

0.00

5.00

10.00

15.00

20.00

25.00

30.00

4 5 6 7 8 9 10 11 12 13 14 15 16 17 18

Number of PRO Processors

Gra

nule

Lat

ency

(min

utes

)

2.6 GHz Power5

5.0 GHz Power5

33

NPOESS Field Terminal Segment Schedule

Build 2.3Build 2.2Build 2.1Build 1.4Build 1.3Build 1.2

Tech Specs PDR

VersionMay 2005

FT NPOESS FTTS, ICD &

FTDSCDR Version

Apr 2006

NPP Ground

ReadinessJul 2007

NPP HRD Demo NLT

April2009

FTS FAT 2.2

Sept 2008

FTS 2.3 S/W Final Release

June 2009

FTS FATBuild 2.3

April 2009

NPOESS C1

LaunchJul 2010

NPP LaunchApril2008

IDPS FAT Build 2.2May 2008

FTS 2.2 S/W

Release Oct 2008

FT NPOESS

ICDPDR

VersionApr 2005

IDPS FAT 2.3

Feb 2009

PDAMar 2005

PDRJun 2005

2004 201020072005 2006 2008 2009

34

NPOESS Direct Readout Mission Points of Contact

Direct Readout Mission POCs: • John Overton: (301) 713-4747• Bill Munley: (301) 713-4782• Joe Mulligan: (301) 713-4803• John van de Wouw: (310) 812-0800

NPOESS websites• Http://www.npoess.noaa.Gov• Http://npoesslib.ipo.noaa.Gov/ (electronic bulletin board)