ATTACHMENT B - PORD 1.pdf
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DRAFT/GeoXO Flight Project OCX
OCXPORD
418-XO-OCXPORD-0119, RM Version, Geostationary Extended Observations (GeoXO) Ocean Color (OCX) Performance and Operational Requirements Document (PORD) Phase B
Version: 0.5 Printed by: hlhedger Printed on: Tuesday, June 27, 2023
No filter applied.
No sort applied.
Generated from DOORS 9.7.2.4
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Contents
1 1Scope
1.1 1Identification
1.2 1Mission Review
1.3 1Document Overview
1.4 1Terminology
1.5 2Definitions
1.6 4Requirement Applicability
2 5Documents
2.1 5Applicable Documents
2.2 5Reference Documents
3 6Sensor Requirements
3.1 6Sensor Definition
3.1.1 6OCX Modes
3.1.1.1 6Safe Mode
3.1.1.2 7Normal Operational Mode
3.1.1.3 7Instrument Diagnostic Mode
3.1.1.4 8Outgassing
3.1.2 8On-Orbit Operations
3.1.2.1 8Operational Zones
3.1.2.1.1 8Performance Zone
3.1.2.2 8Imaging the Sun
3.1.2.3 8Operations After Maneuvers
3.1.2.3.1 8Yaw Flip
3.1.2.3.2 8Stationkeeping
3.1.2.3.3 9Post Storage Activation
3.1.2.4 9Detector Operating Temperatures
3.2 9Normal Operational Mode Sensor Requirements
3.2.1 9Coverage
3.2.1.1 9Coverage Rate
3.2.1.2 10Flexible and Efficient Imaging Pattern
3.2.1.3 10Field of Regard
3.2.1.4 11Simultaneity
3.2.1.5 11Data Latency
Project: GeoXO Flight Project OCX Module: OCXPORD Baseline Version: 0.5
Contents ii
3.2.2 11Channel Definitions, SNR, Dynamic Range
3.2.2.1 11Baseline
3.2.2.2 12System Spectral Response
3.2.2.2.1 12Spectral Response Envelope
3.2.2.2.2 13Within Channel Spectral Response Uniformity
3.2.2.2.3 13Channel Center Wavelength Knowledge
3.2.3 13Spatial Resolution and Sampling
3.2.3.1 13System Modulation Transfer Function
3.2.3.2 13Spatial Response Uniformity
3.2.3.3 14Ringing from a Sharp Edge
3.2.4 14Image Navigation and Registration
3.2.4.1 14Star Sensing
3.2.4.2 14INR Performance Requirements
3.2.4.2.1 14Navigation
3.2.4.2.2 14Frame-to-Frame Registration
3.2.4.2.3 15Within Frame Registration
3.2.4.2.4 15Channel-to-Channel Registration
3.2.5 15Radiometric Accuracy and Precision
3.2.5.1 15Repeatability
3.2.5.1.1 15Pixel-to-Pixel
3.2.5.2 15Coherent Noise
3.2.5.3 16Calibration of Channels
3.2.5.4 17Spatial Uniformity of Data
3.2.5.5 17Crosstalk
3.2.5.5.1 17Channel-to-Channel
3.2.5.5.2 17Within Channel
3.2.5.6 17Blooming
3.2.5.7 18Quantization Step Size
3.2.5.8 18Polarization
3.2.5.8.1 18Polarization Control
3.2.6 18System Linearity
3.2.7 18Data Compression
3.2.7.1 18Lossless Data Compression
3.2.7.2 18Lossy Compression
3.3 19Visualization Algorithm
4 20Design Requirements
4.1 20Reliability
4.2 20Redundancy
Contents iii
4.2.1 20Redundant Component Selectabiltiy
4.2.2 20Interchangability of Flight Model Units
4.2.3 20Cryocooler Operation
4.3 20Mechanical Requirements
4.3.1 20Design Limit Loads
4.3.2 21Yield Strength
4.3.3 22Ultimate Strength
4.3.4 22Unit Stiffness
4.3.5 23Critical Members Design Values
4.3.6 23Redundant Members Design Values
4.3.7 23Selective Design Values
4.3.8 23Fracture Control
4.3.9 23Mechanisms
4.3.10 24Pressurized Units
4.3.11 25Alignment Reference
4.3.12 25Precision Component Assembly
4.4 25Thermal Requirements
4.4.1 25Mission Allowable Temperatures
4.4.2 25Thermal Gradients
4.4.3 25Non-Operational Temperatures
4.4.4 26Thermal Control Hardware
4.4.5 26Detector Cooling Margin
4.4.6 26Radiator
4.4.7 26Heat Pipe (Two-phase Heat Transfer Device)
4.5 27Power Requirements
4.5.1 27Power Regulators and Supplies
4.5.2 27Fuses
4.5.3 27Covers for test Connectors
4.5.4 27Keyed Connectors
4.6 27Onboard Processors Requirements
4.6.1 28Flight Load Non-Volatile Memory
4.6.2 28Commandable Reinitialization
4.6.3 28Deterministic Power-on Configuration
4.6.4 28Fail-safe Recovery Mode
4.7 28Flight Software Requirements
4.7.1 28Language and Methodology
4.7.2 28Flight Software Upload
4.7.3 28Flexibility and Ease of Software Modification
Contents iv
4.7.4 29Version Identifiers
4.7.5 29Flight Processor Resource Sizing
4.7.6 29Software Event Logging
4.7.7 30Warm Restart
4.7.7.1 30Processor Re-Start
4.7.7.2 30Autonomous Re-Start
4.7.8 30Memory Integrity
4.7.8.1 30Memory Verification
4.7.8.2 30Bit Error Detection and Correction
4.7.9 30Memory Dump
4.7.10 30Telemetry Cadence and Dwell Control
4.7.11 30Long-Duration Test
4.7.12 31Unnecessary and Unreachable Software
5 32Ground Support Equipment and Development
5.1 32Electrical System Test Equipment
5.2 32Flight Software Development Environment
5.3 32Ground Processing Demonstration System
5.4 33FM and GSE Shipping Containers
6 34OCX Simulators
6.1 34OCX Instrument Hardware Simulator (OCX-IHS)
6.2 34OCX Instrument Software Simulator (OCX-ISS)
7 36FM Design Verification Requirements
7.1 36Powered-on Operating Time and Trouble-Free Performance Testing
7.2 36Structural and Mechanical Verification Requirements
7.2.1 36Mechanical Test Factors and Duration
7.2.2 38Minimum Workmanship
7.2.3 39Testing in Flight Configuration
7.2.4 39Structural Proof Testing
7.2.5 40Modal Survey Characterization
7.2.6 40Structural Qualification
7.2.7 40Deployment and Articulation Verification
7.2.8 40Life Test
7.2.9 41Mechanical Clearance Verification
7.3 41Electromagnetic Compatibility Verification
7.3.1 41General
7.3.2 41Electrostatic Arc-Discharge Susceptibility
Contents v
7.3.2.1 41External Surface-to-Surface direct discharge
7.3.2.2 41Deep Dielectric Charging
7.3.2.3 41ESD Characteristics
7.4 42Thermal Test Requirements
7.4.1 42General
7.4.1.1 42Thermal Test Chronology
7.4.1.2 42Pressure
7.4.2 43Thermal Vacuum
7.4.2.1 43Transition Rates
7.4.2.2 43Corona Operation
7.4.2.3 43Hot and Cold Start Demonstrations
7.4.2.4 43Heater Verification
7.4.2.5 43Flight Temperature Sensor Verification
7.4.3 44TV Thermal Cycling
7.4.3.1 44Cumulative Cycles
7.4.3.2 44Ambient Pressure Thermal Cycling Substitution
7.4.3.3 44Qualification, Protoflight and Acceptance Temperatures
7.4.3.4 45Survival Heater Verification
7.4.3.5 45Temperature test tolerances
7.4.3.6 45Plateau Criteria
7.4.4 45Thermal Balance (TB)
7.4.4.1 45Balance Points
7.4.4.2 46Instrument Configuration
7.4.4.3 46Accuracy and Knowledge
7.4.4.4 46Steady State Criteria
7.5 46Test Condition Tolerances
8 49Acronyms
Contents vi
Project: GeoXO Flight Project OCX Module: OCXPORD Baseline Version: 0.5
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OCXPORD1
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OCXPORD5
OCXPORD6
OCXPORD7
OCXPORD8
OCXPORD9
OCXPORD10
OCXPORD11
OCXPORD12
OCXPORD13
OCXPORD14
OCXPORD15
Object Number
1.1
1.1.0-1
1.2
1.2.0-1
1.2.0-2
1.2.0-3
1.2.0-4
1.3
1.3.0-1
1.4
1.4.0-1
1.4.0-2
1.4.0-3
1.4.0-4
418-XO-OCXPORD-0119, RM Version, Geostationary Extended Observations (GeoXO) Ocean Color (OCX) Performance and
Operational Requirements Document (PORD) Phase B
1 Scope
1.1 Identification
This Performance and Operational Requirements Document (PORD) sets forth the performance requirements for the National Oceanic and Atmospheric Administration (NOAA) Geostationary eXtended Orbits (GeoXO) Ocean Color (OCX) instrument. The OCX may incorporate additional capabilities described in Appendix 1.
1.2 Mission Review
The OCX is a multi-channel, UV through infrared, passive imaging radiometer used to measure environmental data as part of a 3-axis stabilized, geostationary weather satellite system. The OCX remotely collects imagery of the Earth’s coastal waters for harmful algal blooms, water turbidity, and general water quality, fisheries management, habitat quality/assessment/mapping, pollution tracking, biogeochemical processing in coastal regions, warnings and predictions.
The OCX objectives are as follows:
a) Provide new NOAA ocean color operational data that will be used by NOAA and other public and private agencies to produce forecasts of water quality pollution including turbidity and harmful algal blooms.
b) Provide ocean color operational data that will be used to expand knowledge of coastal waters and ocean processes in the exclusive economic zone (EEZ).
The ocean color instrument provides data to the Ground System via the spacecraft communication system. The Ground System takes the data, spacecraft telemetry data, orbit determination data and other required information and autonomously generates radiometrically calibrated and navigated data (Level 1b data) for the NOAA users.
The Ground System procured by the Government will implement algorithms developed by the OCX Contractor to satisfy performance requirements. The Ground System will calibrate and navigate the data to generate L1b data.
1.3 Document Overview
This document contains all performance requirements for the OCX instrument and Ground Support Equipment (GSE). This document, the General Interface Requirements Document (GIRD), and the OCX Unique Instrument Interface Document (UIID) define all instrument to spacecraft interfaces for the OCX instrument.
1.4 Terminology
The use of “shall” designates a requirement that must be met.
The use of “will” designates a statement of fact or intention of the Government.
The use of “may” designates that permission has been granted by the Government.
The term “TBD” means, “to be determined” and is used when no value is available with subsequent study needed to obtain it.
Project: GeoXO Flight Project OCX Module: OCXPORD Baseline Version: 0.5
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ID
OCXPORD16
OCXPORD17
OCXPORD18
OCXPORD19
OCXPORD20
OCXPORD21
OCXPORD22
OCXPORD23
OCXPORD24
OCXPORD25
OCXPORD26
Object Number
1.4.0-5
1.5
1.5.0-1
1.5.0-2
1.5.0-3
1.5.0-4
1.5.0-5
1.5.0-6
1.5.0-7
1.5.0-8
1.5.0-9
418-XO-OCXPORD-0119, RM Version, Geostationary Extended Observations (GeoXO) Ocean Color (OCX) Performance and
Operational Requirements Document (PORD) Phase B
The term “TBR” means “to be refined/reviewed” for a value that is subject to review for appropriateness and is subject to revision. The Contractor is liable for compliance with the information marked “TBR” as if the “TBR” notation did not exist.
1.5 Definitions
Throughout this document, the following definitions apply (note that Appendix 1 has optional updates to some terms):
Accuracy: Refers to the error in a measurement, that is the difference between the measurement result and the object to be measured (the measured or true value). It includes both systematic and random errors. Systematic errors must be estimated from an analysis of the experimental conditions and techniques. Random errors can be determined, and reduced, through repeated measurements under identical conditions.
Albedo: Refers to the fraction of the solar spectrum taken from the default MODTRAN solar irradiance file (newkur.dat) that is reflected by the Earth at the top of the atmosphere assuming a Lambertian surface (see Ocean Color (OCX) Radiances Upwelling Document, document number 418-XO-RPT-0077, for values).
All requirements/all performance requirements/all operational requirements: Refers to any performance characteristic or requirement in the OCX PORD, OCX UIID, and the
GIRD.
Credible Failure: A failure condition that has a reasonable likelihood of occurrence over the mission life. With consideration of reliability analysis and engineering experience, the Government technical authority will determine credibility of failure. For the purposes of this document, failures of structure, pressure vessels, and pressurized lines and fittings are not considered credible failure modes if those elements comply with the applicable requirements of this document.
Derived Noise Equivalent Delta Radiance (NEDN): Refers to the NEDN required to meet the Noise Equivalent Delta Temperature (NEDT) specification or Signal-to-Noise Ratio (SNR) specification.
EEZ East Region: Any spatial resolution element in the Atlantic along the US East or Gulf Coast including the Gulf of Mexico and within 400 km from the continental US shoreline, with inclusion of Puerto Rico in the Caribbean. This is a region of approximately 6110 km x 400 km in area without including Puerto Rico and 6300 km by 400 km including Puerto Rico EEZ.
EEZ West Region: Any spatial resolution element in the Pacific along the US West coast and within 400 km from the continental US shore plus any spatial resolution element in the Pacific along the Hawaii coast and within 400 km from the Hawaiian shore, plus approximately 2000 km of the observable southern Alaska coast from the GOES West slot (137 West) that falls within 400 km from the Alaskan shore. This is a region of approximately 3600 km by 400 km in area plus 2000 km by 400 km in area for Alaska totaling 5600 km by 400 km in area.
Great Lakes: Any spatial resolution element in the Great Lakes. This is a region of approximately 900 km by 1250 km in area.
Project: GeoXO Flight Project OCX Module: OCXPORD Baseline Version: 0.5
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ID
OCXPORD27
OCXPORD28
OCXPORD29
OCXPORD30
OCXPORD31
OCXPORD32
OCXPORD33
OCXPORD34
OCXPORD35
OCXPORD36
OCXPORD37
Object Number
1.5.0-10
1.5.0-11
1.5.0-12
1.5.0-13
1.5.0-14
1.5.0-15
1.5.0-16
1.5.0-17
1.5.0-18
1.5.0-19
1.5.0-20
418-XO-OCXPORD-0119, RM Version, Geostationary Extended Observations (GeoXO) Ocean Color (OCX) Performance and
Operational Requirements Document (PORD) Phase B
Detector sample or element: Refers to the output of a physical detector after the Analog-to-Digital (A/D) converter and Time Delay and Integration (TDI) processing, if applicable.
Eclipse: Defined as when the solar disk is completely occulted by the Earth or Moon, as viewed from the satellite.
Fixed-Grid Angles: Refers to North/South (NS) and East/West (EW) Euler angles defined as follows. Starting with the orbit reference frame (ORF) in GIRD62 at the ideal satellite location, a positive NS angle is a rotation of the ORF about its +x axis, and a positive EW angle is a subsequent rotation of the rotated frame about its +y axis. The +z axis of the final frame is the line of sight (LOS) represented by the EW and NS fixed-grid angles.
Fully Functional Configuration: Being able to perform the following functions: scene radiance measurement; radiometric calibration; star sensing; on-orbit monitoring of calibration sources and instrument response changes; acquisition of sensor health and status data; generation of sensor, calibration, monitoring, health and status data streams; and reception and execution of command and control data.
Frame: Collection of pixels from a contiguous region as commanded by a minimum bounding rectangle.
Level 0 data: Raw data reconstructed to unprocessed instrument data at full space-time resolution with all available supplemental information to be used in subsequent processing (e.g., ephemeris, health and safety) appended.
Level 1a data: Unpacked and reformatted Level 0 data with all supplemental information to be used in subsequent processing appended. Data generally presented as full space/time resolution. A wide variety of sub-level products are possible. Note:
For OCX, data are not resampled.
Level 1b data: Unpacked and reformatted Level 0 data with all supplemental information to be used in subsequent processing appended. Radiometric calibration and navigation are applied to produce parameters in physical units. Data generally presented as full space/time resolution. Note: For OCX, data are not resampled.
Level 2+ data: Retrieved environmental variables (e.g., sea surface temperature) and higher products.
Navigation: Refers to the determination of the location of each pixel relative to a fixed reference, namely for the OCX, the GRS80 geoid viewed from the idealized geostationary position, with latitude and longitude information appended in the L1b product.
Registration: Refers to maintaining the spatial relationship between pixels within frames, between frames, and between channels.
Launch: The period of time between lift off and the separation of the satellite from the launch vehicle.
Navigation Error: Refers to the angular error of locations in the fixed-grid angles.
Pixel: All spectral channels associated with a given spatial resolution element after processing, including calibration and navigation (Level 1b).
Project: GeoXO Flight Project OCX Module: OCXPORD Baseline Version: 0.5
Page 4 of 49 Printed Tuesday, June 27, 2023
ID
OCXPORD38
OCXPORD39
OCXPORD40
OCXPORD41
OCXPORD42
OCXPORD43
OCXPORD44
OCXPORD45
Object Number
1.5.0-21
1.5.0-22
1.5.0-23
1.5.0-24
1.5.0-25
1.6
1.6.0-1
1.6.0-2
418-XO-OCXPORD-0119, RM Version, Geostationary Extended Observations (GeoXO) Ocean Color (OCX) Performance and
Operational Requirements Document (PORD) Phase B
Polarization Sensitivity: Defined as the ratio of the difference between maximum and minimum output to the sum of the maximum and minimum output obtained when the plane of incoming 100% linearly polarized radiation is rotated through 180 degrees.
Precision: Refers to the standard deviation of a statistically meaningful number of samples of a measurement.
SNR: Refers to the Signal-to-Noise Ratio specification.
Transfer Orbit: The sequence of events that transpires to establish the GeoXO satellite on-station after the GeoXO satellite has separated from the launch vehicle.
Unit: A functional subdivision of a subsystem and generally a self-contained combination of items performing a function necessary for the subsystem's operation.
Examples are electronics unit and sensor unit.
1.6 Requirement Applicability
The requirements in this OCX PORD pertain to the OCX ‘system’, which may include motors, optics, detectors, signal processing electronics and software, and ground processing. The OCX Contractor is not responsible for the whole Ground System, but certain specifications may require some level of ground processing after collection but before data distribution, i.e. decompression, re-sampling, and calibration.
All requirements apply over the entire life of the OCX. Requirements, such as Modulation Transfer Function (MTF) and Image Navigation and Registration (INR), apply after including Level 1b ground processing impacts, except as indicated.
Project: GeoXO Flight Project OCX Module: OCXPORD Baseline Version: 0.5
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OCXPORD46
OCXPORD47
OCXPORD48
OCXPORD49
OCXPORD50
Object Number
2.1
2.1.0-1
2.2
2.2.0-1
418-XO-OCXPORD-0119, RM Version, Geostationary Extended Observations (GeoXO) Ocean Color (OCX) Performance and
Operational Requirements Document (PORD) Phase B
2 Documents
2.1 Applicable Documents
The following form a part of this specification to the extent specified herein.
1. CCSDS Recommendation for Space Data System Standards, Image Data Compression, CCSDS 122.0-B-2, September 2017.
2. CCSDS Recommendation for Space Data System Standards, Low- Complexity Lossless and Near-Lossless Multispectral and Hyperspectral Image Compression, CCSDS 123.0-B-2, February 2019.
3. Structural Design and Test Factors of Safety for Spaceflight Hardware, NASA, Document Number NASA-STD-5001B, August 6, 2014
4. General Environmental Verification Specification for GSFC Flight Programs and Projects, Document Number GSFC-STD-7000B, April 28, 2021
5. NASA Payload Safety Requirements NASA-STD-8719.24A, March 30, 2022, with NASA-STD-8719.24-ANNEX Rev B, May 22, 2023
6. Geostationary eXtended Observations (GeoXO) Ocean Color (OCX) Radiances Upwelling Document, 418-XO-RPT-0077
2.2 Reference Documents
The following are reference documents.
1. General Interface Requirements Document (GIRD), Document number
418-XO-GIRD-0041
2. Report Concerning Space Data System Standards GREEN BOOK: LOSSLESS
MULTISPECTRAL AND HYPERSPECTRAL IMAGE COMPRESSION,
Informational Report CCSDS 120.2-G-2, December 2022
3. SPECTRAL PREPROCESSING TRANSFORM FOR MULTISPECTRAL AND
HYPERSPECTRAL IMAGE COMPRESSION” Recommended Standard CCSDS 122.1-B-1, September 2017
4. Moving Mechanical Assemblies for Space and Launch Vehicles, AIAA S-114A-2020, Jan. 14, 2021
5. General Specification for Assemblies, Moving Mechanical, for Space and Launch Vehicles, Document Number MIL-A-83577B, February 1, 1988
6. Space Mechanisms Handbook, Document Number NASA TP-1999-206988, March 1, 2002
Project: GeoXO Flight Project OCX Module: OCXPORD Baseline Version: 0.5
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OCXPORD60
OCXPORD61
OCXPORD62
OCXPORD63
Object Number
3.1
3.1.1
3.1.1.0-1
3.1.1.0-2
3.1.1.0-3
3.1.1.0-4
3.1.1.0-5
3.1.1.0-6
3.1.1.1
3.1.1.1.0-1
3.1.1.1.0-2
3.1.1.1.0-3
418-XO-OCXPORD-0119, RM Version, Geostationary Extended Observations (GeoXO) Ocean Color (OCX) Performance and
Operational Requirements Document (PORD) Phase B
3 Sensor Requirements
3.1 Sensor Definition
3.1.1 OCX Modes
The OCX shall execute commands to individually enable and disable each autonomous function.
Rationale: Autonomous capability needs to be able to be disengaged as well.
The OCX shall initiate all commanded mode transitions in no more than 20 seconds after receipt of command.
Rationale: Mode transitions should occur rapidly for operators.
The OCX shall make limits and triggers of autonomous functions changeable by command.
Rationale: Autonomous functions should be controlled by operators if there is a special need to do so.
The OCX shall transition from its current mode to any other mode without causing permanent damage to itself.
Rationale: Mode transitions should occur without damage.
The OCX shall indicate the mode of the instrument in housekeeping telemetry.
Rationale: Knowledge of instrument modes is needed for data processing.
The OCX shall provide command and housekeeping telemetry functions in all powered modes.
Rationale: Command and housekeeping telemetry is necessary for monitoring instrument health at all times.
3.1.1.1 Safe Mode
The OCX shall implement a Safe Mode.
Rationale: The OCX needs a Safe Mode to enable straightforward storage.
The OCX shall be in a thermally and optically safe configuration for an indefinite period of time while in Safe Mode.
Rationale: Safe Mode of instrument enables a thermally and optically safe configuration for storage.
The OCX shall enter Safe Mode upon detection of internal faults capable of causing permanent damage to the instrument.
Rationale: The OCX needs to employ the Safe Mode after fault detection to ensure that there is time for recovery.
Project: GeoXO Flight Project OCX Module: OCXPORD Baseline Version: 0.5
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OCXPORD66
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OCXPORD68
OCXPORD69
OCXPORD70
OCXPORD71
OCXPORD72
OCXPORD73
OCXPORD74
Object Number
3.1.1.2
3.1.1.2.0-1
3.1.1.2.0-2
3.1.1.3
3.1.1.3.0-1
3.1.1.3.0-2
3.1.1.3.0-3
3.1.1.3.0-4
3.1.1.3.0-5
3.1.1.3.0-6
3.1.1.3.0-7
418-XO-OCXPORD-0119, RM Version, Geostationary Extended Observations (GeoXO) Ocean Color (OCX) Performance and
Operational Requirements Document (PORD) Phase B
3.1.1.2 Normal Operational Mode
The OCX shall be in a fully functional configuration while in Normal Operational Mode.
Rationale: Normal mode is used for observations that require full functionality.
The OCX shall meet all performance requirements while in Normal Operational Mode without receiving commands or data loads for a minimum of 7 days.
Rationale: Autonomy is required for a period of 7 days, without impacting performance.
3.1.1.3 Instrument Diagnostic Mode
The OCX shall implement an Instrument Diagnostic Mode.
Rationale: Diagnostic mode is needed for diagnosing anomalies.
The OCX shall be in a fully functional configuration while in Instrument Diagnostic Mode.
Rationale: Diagnostic mode must be fully functional.
The OCX shall by command send selected channels while in Instrument Diagnostic Mode.
Rationale: Diagnostic mode will afford commandable channel engagement for diagnosing anomalies.
The OCX shall by command send the individual measurement in those cases where TDI data is digitally processed off the focal plane while in Instrument Diagnostic Mode.
Rationale: Diagnostic mode will send data from TDI if employed to help in validation and in assessing anomalies.
The OCX shall by command send data from all detectors while in Instrument Diagnostic Mode.
Rationale: Diagnostic mode will send data from all detectors to help in validation and in assessing anomalies.
The OCX shall by command send the same data both compressed and uncompressed if the data is capable of being compressed while in Instrument Diagnostic Mode.
Rationale: Diagnostic mode will send compressed and uncompressed to help in validation and in assessing anomalies.
The OCX shall by command send all bits from the A to D converter while in Instrument Diagnostic Mode.
Rationale: Diagnostic mode will send all bits to help in validation and in assessing anomalies.
Project: GeoXO Flight Project OCX Module: OCXPORD Baseline Version: 0.5
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OCXPORD75
OCXPORD76
OCXPORD77
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OCXPORD81
OCXPORD82
OCXPORD84
OCXPORD86
OCXPORD87
OCXPORD90
OCXPORD91
OCXPORD92
OCXPORD93
OCXPORD94
Object Number
3.1.1.3.0-8
3.1.1.3.0-9
3.1.1.4
3.1.1.4.0-1
3.1.2
3.1.2.1
3.1.2.1.1
3.1.2.1.1.0-
3.1.2.2
3.1.2.2.0-1
3.1.2.3
3.1.2.3.1
3.1.2.3.1.0-
3.1.2.3.2
3.1.2.3.2.0-
418-XO-OCXPORD-0119, RM Version, Geostationary Extended Observations (GeoXO) Ocean Color (OCX) Performance and
Operational Requirements Document (PORD) Phase B
The OCX shall by command perform electronic in-flight calibration.
Rationale: Diagnostic mode electronic in-flight calibration will help in validation and in assessing anomalies.
The OCX shall by command send dwell data (increased samples per second of a particular telemetry measurand) while in Diagnostic Mode.
Rationale: Diagnostic mode dwell data will help in validation and in assessing anomalies.
3.1.1.4 Outgassing
The post-launch outgas period shall be no longer than 14 days.
Rationale: The OCX will sublimate and evaporate contaminants from hardware to prevent contamination from jeopardizing performance.
3.1.2 On-Orbit Operations
3.1.2.1 Operational Zones
3.1.2.1.1 Performance Zone
The OCX shall meet all performance requirements for all pixels whose solar zenith angle (SZA) is less than 70 degrees.
Rationale: SNR, on-orbit calibration, and accuracy are met in well-illuminated conditions during the day and may degrade in performance outside this region. Solar zenith angle is the angle measured off local zenith to the moving sun’s position.
3.1.2.2 Imaging the Sun
The OCX shall survive the presence of the sun within the field of regard without sustaining any permanent degradation in performance.
Rationale: The sun must not result in damage to the instrument.
3.1.2.3 Operations After Maneuvers
3.1.2.3.1 Yaw Flip
The OCX shall meet all radiometric, coverage and INR requirements within 30 minutes after the spacecraft interface has returned to being within specification following a yaw flip.
Rationale: If the spacecraft executes a yaw flip, the instrument recovery will occur in this duration after the interface is restored to nominal conditions.
3.1.2.3.2 Stationkeeping
With the exception of a yaw flip, the OCX shall meet all radiometric, coverage and INR requirements within 2 minutes after the spacecraft interface has returned to being within specification following spacecraft maneuvers.
Project: GeoXO Flight Project OCX Module: OCXPORD Baseline Version: 0.5
Page 9 of 49 Printed Tuesday, June 27, 2023
ID
OCXPORD94
OCXPORD95
OCXPORD96
OCXPORD97
OCXPORD98
OCXPORD99
OCXPORD100
OCXPORD101
OCXPORD102
OCXPORD103
OCXPORD104
Object Number
3.1.2.3.2.0-
3.1.2.3.3
3.1.2.3.3.0-
3.1.2.4
3.1.2.4.0-1
3.1.2.4.0-2
3.2
3.2.1
3.2.1.1
3.2.1.1.0-1
3.2.1.1.0-2
418-XO-OCXPORD-0119, RM Version, Geostationary Extended Observations (GeoXO) Ocean Color (OCX) Performance and
Operational Requirements Document (PORD) Phase B
Rationale: If the spacecraft executes a different maneuver than a yaw flip, the instrument recovery will occur in this short duration after the interface is restored to nominal conditions.
3.1.2.3.3 Post Storage Activation
The OCX shall meet all requirements within 4 days of turn on after post storage activation.
3.1.2.4 Detector Operating Temperatures
The OCX detector set-point temperature shall be selectable by command to ensure radiometric performance during degradation at end of life.
Rationale: This provide for set point temperature adjustments near the operating temperature range that may be needed due to gain changes or troubleshooting.
The OCX detector temperatures shall be included in telemetry to support radiometric performance assessment.
Rationale: OCX may be thermally sensitive due to its detectors and thermal telemetry will provide information for potential corrections and troubleshooting.
3.2 Normal Operational Mode Sensor Requirements
3.2.1 Coverage
3.2.1.1 Coverage Rate
Note that these coverage requirements define a capability and not a definitive operational scenario. Rather, NOAA anticipates operating OCX in an asynchronous manner that uses information from other instruments and models to identify potential regions for scanning/stepping by OCX. To perform its tasks, commanding of OCX for these targeted observations will be based on priorities and availability.
The OCX shall acquire concurrently within 3 hours:
a) Coverage Regions: Either EEZ East Region (EEZE) plus Great Lakes (GL), or EEZ West Region (EEZW). Note that EEZE+GL is larger than EEZW.
b) Any other observations required to meet radiometric and INR requirements
Rationale: When covering the driving EEZE plus Great Lakes, the coverage including all calibrations will take 3 hours or less to ensure a timely coverage rate for the instrument that may be used to cover smaller areas in proportionally smaller times.
Nominally coverage from OCX on the GeoXO Imager satellite (GeoI) at 75 W (GeoI- East) will cover EEZE plus Great Lakes and OCX on GeoI-West at 137 W will cover
EEZW.
Project: GeoXO Flight Project OCX Module: OCXPORD Baseline Version: 0.5
Page 10 of 49 Printed Tuesday, June 27, 2023
ID
OCXPORD105
OCXPORD106
OCXPORD107
OCXPORD108
OCXPORD109
OCXPORD110
OCXPORD111
OCXPORD112
OCXPORD1346
OCXPORD113
Object Number
3.2.1.1.0-3
3.2.1.1.0-4
3.2.1.2
3.2.1.2.0-1
3.2.1.2.0-2
3.2.1.2.0-3
3.2.1.2.0-4
3.2.1.2.0-5
3.2.1.2.0-6
3.2.1.3
418-XO-OCXPORD-0119, RM Version, Geostationary Extended Observations (GeoXO) Ocean Color (OCX) Performance and
Operational Requirements Document (PORD) Phase B
The OCX shall interrupt current operations by issued command and start the acquisition of a new frame, after a frame coordinate upload, within 30 seconds.
Rationale: The OCX must be commandable to cover regions of interest. Regions will be covered with the same instrument coverage rate, with smaller areas taking proportionally less time.
All corresponding EEZE+GL frames in consecutive revisits shall be spaced at an average time of no more than 3 hours with peak deviation of no more than +/- 30 seconds.
Rationale: The OCX revisit of the entire region should be repeatable if commanded with a regular cadence with limited temporal deviation to support operations.
3.2.1.2 Flexible and Efficient Imaging Pattern
The OCX sensor shall observe an area of commanded size anywhere within the field of regard when commanded.
Rationale: Permits flexible tasking of OCX to regions of interest.
The scan area and geographic location shall be selectable from one frame to the next.
Rationale: Permits flexible tasking of OCX to regions of interest.
The OCX shall be designed such that the Earth-scanning patterns are fully programmable on-orbit.
Rationale: Permits flexible tasking of OCX to regions of interest.
The OCX shall accept fixed grid coordinates for all imaging patterns.
Rationale: Permits mapping to fixed grid.
The OCX shall set the center location of each frame to Fixed Grid Frame coordinates specified by command.
Rationale: Permits centering on fixed grid point for ease of Fixed Grid mapping.
The OCX shall implement an adjustable and commandable scan optimization that accepts priorities from operations and avoids clouds in illuminated regions using an uploaded cloud mask for the cases of a) faster coverage, b) targeted regions of interest.
Rationale: Cloud cover can be variable and requires flexibility in commanding for amount and extent. Adjustable and commandable scan optimization including prioritization by operations will enable either faster acquisition of the coverage regions specified in OCXPORD104 or additional targeted regions of interest.
3.2.1.3 Field of Regard
Project: GeoXO Flight Project OCX Module: OCXPORD Baseline Version: 0.5
Page 11 of 49 Printed Tuesday, June 27, 2023
ID
OCXPORD114
OCXPORD115
OCXPORD116
OCXPORD117
OCXPORD118
OCXPORD119
OCXPORD120
OCXPORD123
OCXPORD124
OCXPORD125
OCXPORD126
Object Number
3.2.1.3.0-1
3.2.1.4
3.2.1.4.0-1
3.2.1.4.0-2
3.2.1.5
3.2.1.5.0-1
3.2.1.5.0-2
3.2.2
3.2.2.1
3.2.2.1.0-1
3.2.2.1.0-2
418-XO-OCXPORD-0119, RM Version, Geostationary Extended Observations (GeoXO) Ocean Color (OCX) Performance and
Operational Requirements Document (PORD) Phase B
The OCX Field of Regard (FOR) shall be a minimum of 16.3 degrees to permit observations within the earth's Full Disk.
Rationale: This covers extreme angles of the EEZ.
3.2.1.4 Simultaneity
Corresponding pixels in all spectral channels shall be calculated from detector samples that are collected within 20 seconds of each other.
Rationale: Spectrally simultaneous observations provide observations of the same features and avoid artifacts in resulting data.
All adjacent pixels shall be calculated from detector samples collected within 2 minutes of each other, or OCX shall provide overlap of 42 urad near adjacent observation edges.
Rationale: This minimum overlap of adjacent observing edges, 42 urad or 1.5 km at nadir, will provide some shear mitigation for higher-level product processing when the observation edges are not made within 2 min of each other.
3.2.1.5 Data Latency
The OCX shall contribute to the total data latency for the Level 1b product of no more than 5 minutes for calibrated, navigated radiances.
Data latency is measured from the time the instrument collects all samples for an earth scene (or frame) to the time the data is available for dissemination on the ground as Level 1b data. The OCX contribution to data latency includes delay of delivery of data to the spacecraft and delay due to ground algorithm processing (i.e., INR).
Rationale: Latency between the last observation of the input data to the Level 1b processing and the availability of the data for further processing should be as short as practical.
3.2.2 Channel Definitions, SNR, Dynamic Range
3.2.2.1 Baseline
The OCX shall collect hyperspectral data in the range 0.350 – 1.02 um.
Rationale: A large number of narrow adjacent spectral samples allows for flexibility for current and future algorithm development to distinguish algal species.
The OCX SNR shall be greater than or equal to the values listed in the SNR table below, when computed over the listed spectral widths, for the at-aperture radiance provided in the Ocean Color (OCX) Radiances Upwelling Document, document number
418-XO-RPT-0077.
Rationale: These SNR values are needed at the L1b output in order to detect water leaving radiance properties via higher level product generation. Note that FWHM is the full width half maximum of the spectral resolution element.
SNR Table
Project: GeoXO Flight Project OCX Module: OCXPORD Baseline Version: 0.5
Page 14 of 49 Printed Tuesday, June 27, 2023
ID
OCXPORD142
OCXPORD143
OCXPORD144
OCXPORD145
OCXPORD146
OCXPORD147
OCXPORD148
OCXPORD149
OCXPORD150
OCXPORD151
OCXPORD153
OCXPORD154
Object Number
3.2.3.2.0-2
3.2.3.3
3.2.3.3.0-1
3.2.4
3.2.4.1
3.2.4.1.0-1
3.2.4.2
3.2.4.2.0-1
3.2.4.2.0-2
3.2.4.2.1
3.2.4.2.1.0-
3.2.4.2.2
418-XO-OCXPORD-0119, RM Version, Geostationary Extended Observations (GeoXO) Ocean Color (OCX) Performance and
Operational Requirements Document (PORD) Phase B
5% Nmax shall be less than 4% of the step function for an rms over the sampling-to-edge phasing and the channel-to-channel relative phasing. The values of X include all distances between +17 microradians and -17 microradians.
Rationale: Requirement limits signal contamination from bright scene regions into dark scene regions.
3.2.3.3 Ringing from a Sharp Edge
or both the North/South and East/West edges, the OCX shall not overshoot the top of an edge or undershoot the bottom of edge by more than 2% of the height of the edge where:
a) The height and the overshoot/undershoot are measured in radiance units.
b) The edge delineates a 10% albedo region from a 90% albedo.
c) The overshoot is averaged over all phases of the detector sample grid to edge position.
Rationale: Requirement limits ringing response or overshoot near a sharp edge.
3.2.4 Image Navigation and Registration
3.2.4.1 Star Sensing
If autonomous star sensing is required to meet navigation requirements, the OCX shall have an on-board star catalog provided by the OCX Contractor, which is loadable and modifiable from the ground and covers a span of two weeks.
Rationale: If employed, star sensing will require a star catalog and not rely on operators.
3.2.4.2 INR Performance Requirements
All INR requirements listed herein refer to location error of detector samples as expressed in fixed-grid angles; i.e., the requirements apply to the end-to-end system, taking all instrument, spacecraft, and ground processing effects into account. Unless otherwise specified, all INR requirements in this document are specified as North/South and East/West fixed-grid angles, in microradians, 3-sigma, and refer to all hours of operation as defined by the operational zones.
In the context of OCX INR, 3-sigma error is defined to be equal to the 99.73rd percentile of the absolute values of all INR error observations collected over each 24-hour period from local noon to local noon. When INR requirements are temporarily suspended, due to Sun/Earth geometry or maneuver outages (including recovery time), the raw errors during the requirements suspension period should be ignored.
3.2.4.2.1 Navigation
The OCX navigation error shall not exceed 6.3 microradians, 3-sigma, per axis.
3.2.4.2.2 Frame-to-Frame Registration
Project: GeoXO Flight Project OCX Module: OCXPORD Baseline Version: 0.5
Page 15 of 49 Printed Tuesday, June 27, 2023
ID
OCXPORD155
OCXPORD156
OCXPORD157
OCXPORD159
OCXPORD160
OCXPORD161
OCXPORD162
OCXPORD165
OCXPORD166
OCXPORD167
OCXPORD172
OCXPORD173
Object Number
3.2.4.2.2.0-
3.2.4.2.3
3.2.4.2.3.0-
3.2.4.2.4
3.2.4.2.4.0-
3.2.4.2.4.0-
3.2.5
3.2.5.1
3.2.5.1.1
3.2.5.1.1.0-
3.2.5.2
3.2.5.2.0-1
418-XO-OCXPORD-0119, RM Version, Geostationary Extended Observations (GeoXO) Ocean Color (OCX) Performance and
Operational Requirements Document (PORD) Phase B
Frame-to-frame registration error shall not exceed 6.3 microradians, 3-sigma, per axis.
Frame-to-frame registration error is the difference in navigation error for an earth location in two consecutive frames within the same channel.
3.2.4.2.3 Within Frame Registration
Within a frame in the same channel, any two pixels shall be separated by the known fixed distance to within an error of 6.3 microradians, 3-sigma, measured radially.
3.2.4.2.4 Channel-to-Channel Registration
Channel-to-channel registration error, or co-registration error, is the difference in line-of-sight fixed-grid angles between spectral channels for any given pixel in the same frame.
Rationale: Co-registration for L1b applies to true line-of-sight fixed grid angles rather than the knowledge of those angles.
Co-registration errors between any two spectral channels shall not exceed 1.7 microradians, on a 3-sigma, per axis basis.
Rationale: This uses the same Government methodology as the PRAD.
3.2.5 Radiometric Accuracy and Precision
3.2.5.1 Repeatability
3.2.5.1.1 Pixel-to-Pixel
For all channels, while viewing a stable, uniform calibration source over expected geostationary environmental conditions and calibration frequency, the OCX shall have a pixel-to-pixel repeatability less than the derived NEDN. Channels will be characterized as if viewing a 100% albedo calibration source.
Rationale: Pixel-to-pixel repeatability should be less than the required noise level to not interefere with scene data collection.
3.2.5.2 Coherent Noise
For all channels, while viewing a stable, uniform calibration source over expected geostationary environmental conditions and calibration frequency, the OCX shall have no spatial coherent noise spectral component exceedances. The spatial coherent noise is defined as the variation in the 2-D Fourier transform of the pixel output of a square region of 0.042 radian by 0.042 radian following all calibration, sampling and detrending. An exceedance is defined as any spatial frequency whose scaled Fourier coefficients are greater than 25 percent of the derived NEdN. The scaled Fourier coefficients are defined using the following equations to scale the amplitude to match the amplitude of a single harmonic.
Project: GeoXO Flight Project OCX Module: OCXPORD Baseline Version: 0.5
Page 16 of 49 Printed Tuesday, June 27, 2023
ID
OCXPORD173
OCXPORD174
OCXPORD175
OCXPORD176
OCXPORD177
Object Number
3.2.5.2.0-1
3.2.5.3
3.2.5.3.0-1
3.2.5.3.0-2
3.2.5.3.0-3
418-XO-OCXPORD-0119, RM Version, Geostationary Extended Observations (GeoXO) Ocean Color (OCX) Performance and
Operational Requirements Document (PORD) Phase B where x(j,l) are the radiances, N and M are the image size in pixels and Xa are the scaled Fourier coefficients. Detrending allows the removal of scene trends by subtracting the filtered scene using a square box car filter that is 10% of the minimum scene dimension. Edge effects of detrending may be reduced by using a symmetric boundary condition.
Note: The width of bin is defined by the fixed grid spacing. Channels will be characterized as if viewing a 100% albedo calibration source.
Rationale: Coherent noise in a Level 1b product should be less than the one fourth of the noise level to avoid interference.
3.2.5.3 Calibration of Channels
The OCX shall have an on-board optical path calibration capability.
Rationale: An on-board calibration capability of high quality improves near real time calibration accuracy compared to that of vicarious calibration. Additionally, vicarious calibration will also be used.
The OCX shall have an on-board calibration capability for all channels that provides absolute accuracy with traceability to NIST of 2.0%, 1-sigma, or less in the earth albedo measurements for scenes from 3% albedo through 100% albedo.
Rationale: Traceability to NIST (as documented in the SOW) provides improved absolute accuracy for near real time calibration. Calibration of water leaving radiance necessitates calibration accuracy that remains linear down to low albedo levels. Tight absolute accuracy improves the quality of ocean color science as the ocean color signal is a small fraction of the total top of atmosphere scene.
The OCX shall have a calibration capability for all channels that provides drift in calibrated radiances of no more than 0.5% over the OCX lifetime.
Rationale: Instrument degradation over the lifetime, if not corrected in processing, may be misunderstood and changing geophysical parameters over time. Degradation of the instrument and correction method(s) need to be understood and reported to the Government for use in near real time through the instrument Contractor calibration algorithms (updating calibration coefficients)
Project: GeoXO Flight Project OCX Module: OCXPORD Baseline Version: 0.5
Page 17 of 49 Printed Tuesday, June 27, 2023
ID
OCXPORD178
OCXPORD179
OCXPORD180
OCXPORD181
OCXPORD182
OCXPORD183
OCXPORD184
OCXPORD185
OCXPORD186
OCXPORD187
Object Number
3.2.5.3.0-4
3.2.5.4
3.2.5.4.0-1
3.2.5.4.0-2
3.2.5.5
3.2.5.5.1
3.2.5.5.1.0-
3.2.5.5.2
3.2.5.5.2.0-
3.2.5.6
418-XO-OCXPORD-0119, RM Version, Geostationary Extended Observations (GeoXO) Ocean Color (OCX) Performance and
Operational Requirements Document (PORD) Phase B
The OCX shall have a calibration capability for all channels that provides RMS repeatability of 0.2% or less. This requirement is met when no fewer than N independent calibrations are performed as closely as possible together in time and the RMS variation in each calibration coefficient is less than the specified level. N is the number of calibrations required to state at the 90% confidence level that the requirement has been met.
Rationale: Short term RMS repeatability of this level ensures high quality relative accuracy calibration.
3.2.5.4 Spatial Uniformity of Data
The OCX shall have less than 0.3%, 1-sigma, change in response in the calibrated pixel data over the field of regard specified in OCXPORD114 while viewing a stable, uniform calibration source over expected geostationary environmental conditions and calibration frequency.
Rationale: This covers extreme angles of the EEZ.
Channels will be characterized as if viewing a 100% albedo calibration source.
Rationale: Calibrated data needs to spatial uniform so that variations in the data are not misinterpreted to be real signal variations.
3.2.5.5 Crosstalk
3.2.5.5.1 Channel-to-Channel
The OCX channel-to-channel (electrical, optical, spatial, spectral) crosstalk shall be less than the derived NEDN. Channel-to-channel crosstalk is defined as the change in any channel output when one channel's illumination is changed from 0.1 Nmax to a radiance of Nmax while all other channels remain illuminated at a radiance level less than 0.1 Nmax.
Rationale: Crosstalk between any spectral channels needs to be less than the noise level to minimize spectral artifacts in the data that may be misunderstood to be real features in the data.
3.2.5.5.2 Within Channel
Non-adjacent pixel to pixel within channel cross talk, not including diffraction, shall be less than the derived NEDN. Within channel crosstalk is defined as the change in any non-adjacent pixel when one pixel’s radiance is changed from 0.1 Nmax to a radiance of Nmax while all other pixels in the same band remain illuminated at a radiance level less than 0.1 Nmax.
Rationale: Crosstalk within a spectral channel needs to be less than the noise level to minimize artifacts in the data that may be misunderstood to be real features in the data.
3.2.5.6 Blooming
Project: GeoXO Flight Project OCX Module: OCXPORD Baseline Version: 0.5
Page 18 of 49 Printed Tuesday, June 27, 2023
ID
OCXPORD188
OCXPORD189
OCXPORD190
OCXPORD192
OCXPORD193
OCXPORD194
OCXPORD195
OCXPORD196
OCXPORD197
OCXPORD198
OCXPORD199
OCXPORD200
OCXPORD201
OCXPORD202
Object Number
3.2.5.6.0-1
3.2.5.7
3.2.5.7.0-1
3.2.5.8
3.2.5.8.1
3.2.5.8.1.0-
3.2.6
3.2.6.0-1
3.2.7
3.2.7.0-1
3.2.7.0-2
3.2.7.1
3.2.7.1.0-1
3.2.7.2
418-XO-OCXPORD-0119, RM Version, Geostationary Extended Observations (GeoXO) Ocean Color (OCX) Performance and
Operational Requirements Document (PORD) Phase B
In all directions from the edge of a 500 by 500 microradian bright target at twice Nmax, all detector outputs in all channels shall recover to normal operation within 24 microradians.
Rationale: Specular solar glint regions are limited to within this spatial distance from the solar sub-point.
3.2.5.7 Quantization Step Size
The quantizing step size for all detector samples shall be less than half the derived
NEDN.
Rationale: Signal quantization by the analog to digital converter should not be the driver in the noise budget in order to avoid having discrete jumps in signal level that can lead to digital artifacts (blocky) data.
3.2.5.8 Polarization
3.2.5.8.1 Polarization Control
Channels shall have less than 3% polarization sensitivity to the incoming light over the FOR specified in OCXPORD114.
Rationale: Polarization sensitivity should be small to limit signal variations with angle.
A polarization sensitivity of less than 3% is important for aerosol characterization for atmospheric correction, particularly 600 nm to 890 nm. Note polarization may vary with wavelength.
3.2.6 System Linearity
The OCX shall have linear radiometric response, before calibration, such that all points within the dynamic range vary from a linear best fit by no more than 1% of Nmax.
Rationale: Detectors may not be perfectly linear, but small deviations can be well corrected.
3.2.7 Data Compression
The OCX may perform data compression on all data.
Rationale: Data rates may be excessive for downlink without compression.
The OCX may perform lossy data compression.
Rationale: Constraint on application is not to degrade data beyond performance levels
3.2.7.1 Lossless Data Compression
If performed, lossless data compression shall be in accordance with Applicable Document 1 and Applicable Document 2.
Rationale: Lossless data compression when used will follow these references.
3.2.7.2 Lossy Compression
Project: GeoXO Flight Project OCX Module: OCXPORD Baseline Version: 0.5
Page 19 of 49 Printed Tuesday, June 27, 2023
ID
OCXPORD203
OCXPORD204
OCXPORD205
OCXPORD206
OCXPORD207
OCXPORD208
OCXPORD209
OCXPORD210
Object Number
3.2.7.2.0-1
3.2.7.2.0-2
3.3
3.3.0-1
3.3.0-2
3.3.0-3
3.3.0-4
3.3.0-5
418-XO-OCXPORD-0119, RM Version, Geostationary Extended Observations (GeoXO) Ocean Color (OCX) Performance and
Operational Requirements Document (PORD) Phase B
If performed, lossy compression shall not prevent the OCX from meeting requirements, most notably MTF, SNR, and coherent noise.
Rationale: Calibration data needs to be a high quality so nominally it should not be compressed as it may impact performance. Reference documents provide additional information on data compression.
All calibration data shall be lossless compressed or uncompressed.
Rationale: Calibration data needs to be a high quality so nominally it should not be compressed as it may impact performance.
3.3 Visualization Algorithm
The OCX Visualization Algorithm (VA) shall provide for visualization of radiances at each spectral channel.
The VA may utilize spatial and spectral resampling as needed.
The VA shall create spatially uniform output on the fixed grid of less than or equal to
8.4 µrad by less than or equal to 8.4 µrad that also complies with OCXPORD155 (frame-to-frame navigation) and OCXPORD157 (within-frame registration).
The VA shall create spectrally uniform output images of all spectral channels over full-width-half-maximum spectral widths.
For the VA algorithm output, the performance against OCXPORD133 (within-channel spectral response uniformity) shall be less than 6x the derived noise for all channels less than or equal to 0.890 µm.
Rationale: The VA enhances L1b data to produce images that are spatially and spectrally uniform.
Project: GeoXO Flight Project OCX Module: OCXPORD Baseline Version: 0.5
Page 20 of 49 Printed Tuesday, June 27, 2023
ID
OCXPORD1000
OCXPORD1001
OCXPORD1002
OCXPORD1003
OCXPORD1004
OCXPORD1005
OCXPORD1006
OCXPORD1007
OCXPORD1008
OCXPORD1009
OCXPORD1010
OCXPORD1011
OCXPORD1012
OCXPORD1013
OCXPORD1014
OCXPORD1015
OCXPORD1016
OCXPORD1017
OCXPORD1018
Object Number
4.1
4.1.0-1
4.1.0-2
4.1.0-3
4.1.0-4
4.1.0-5
4.1.0-6
4.2
4.2.1
4.2.1.0-1
4.2.2
4.2.2.0-1
4.2.3
4.2.3.0-1
4.3
4.3.0-1
4.3.0-2
4.3.1
418-XO-OCXPORD-0119, RM Version, Geostationary Extended Observations (GeoXO) Ocean Color (OCX) Performance and
Operational Requirements Document (PORD) Phase B
4 Design Requirements
4.1 Reliability
The OCX shall demonstrate by…
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