Attachment F- IRD-SS-DCS.pdf

Effective Date: February 10, 2022 418-XO-IRD-0044 Responsible Organization: GeoXO Flight Project/Code 418 Baseline Version 1.0

Geostationary Extended Observations (GeoXO)

SS to Data Collection System (SS-DCS)

Interface Requirements Document (IRD)

February 10, 2022

Effective Date: February 10, 2022 418-XO-IRD-0044

Geostationary Extended Observations (GeoXO) SS to Data Collection System (SS-DCS) Interface

Requirements Document (IRD) Signature page

Prepared by:

Electronically approved by:

01/21/2022

Thomas W. Kenney Date GeoXO Flight Project, Systems Engineer NASA GSFC, Code 418

Reviewed by:

02/03/2022

Steven W. Bidwell Date GeoXO Flight Project, Mission Systems Engineer NASA GSFC, Code 599

02/04/2022

Alexander Krimchansky Date GeoXO Program, Mission Systems Engineer NASA GSFC, Code 590

Electronically approved by: 01/25/2022 Kevin M. Mcmahon Date GeoXO Ground, Mission Systems Engineer NASA GSFC, Code 416

Approved by:

02/10/2022

Jason Hair Date GeoXO Flight Project, Project Manager NASA GSFC, Code 418

/GeoXO Flight Project Spacecraft

DCSIRD

418-XO-IRD-0044, RM Version, Geostationary eXtended Observations (GeoXO) SS to Data Collection System (SS-DCS) Interface Requirements Document (IRD)

Version: 1.0 Printed by: rkhoover Printed on: Monday, February 14, 2022

No filter applied.

No sort applied.

Generated from DOORS 9.7.2.4

Contents

1 1Introduction

1.1 1General GeoXO Description

1.1.1 1Mission Objectives

1.1.2 1Mission Description

1.2 1DCS Scope

1.3 2Applicable Documents

1.4 2Requirements Terminology

2 3DCS Service and Interface Description

3 4DCS RF Interface Performance Requirements

3.1 4Simultaneous Links

3.2 4NTIA Compliance

3.3 4Power Flux Density Limits

3.4 4Radio Astronomy Band Protection

3.5 4Long Term Frequency Stability

3.6 4Short Term Frequency Stability

3.7 4Spacecraft Phase Noise

3.8 4DCPR Unwanted Emissions

3.9 4Spacecraft Intermodulation

4 6DCPR RF Interface Performance Requirements

4.1 6General DCPR Requirements

4.1.1 6DCPR Requirements Summary

4.1.2 6Link Margin Requirement

4.1.3 7DCPR End-to-End BER

4.2 7Uplink DCPR RF Interface Requirements

4.2.1 7Uplink Center Frequency and Frequency Stability

4.2.2 7Uplink EIRP and Capacity

4.2.3 7Uplink G/T

4.2.4 7Uplink Polarization

4.2.5 7Uplink Atmospheric Loss

4.2.6 7Uplink Polarization Loss

4.2.7 7Uplink Pointing Loss

4.2.8 8Forward Error Correction

Project: GeoXO Flight Project Spacecraft Module: DCSIRD Baseline Version: 1.0

Contents ii

4.2.9 8Uplink Data Rates

4.2.10 8Uplink Modulation

4.2.11 8Uplink Format

4.2.12 8Uplink Phase Noise

4.2.13 8Spacecraft Receive Coverage

4.2.14 8Rejection of Out of Band Signals

4.2.15 8Transponder Intermediate Frequency Filtering Requirements

4.3 9Downlink DCPR Interface Requirements

4.3.1 9Downlink Center Frequency

4.3.2 9Ground Antenna G/T and Spacecraft EIRP

4.3.3 9Spacecraft Transmit Coverage

4.3.4 9DCPR Downlink Polarization

4.3.5 9DCPR Receive Eb/No

4.3.6 9Downlink Atmospheric Loss

4.3.7 9Downlink Pointing Loss

4.3.8 9Downlink Polarization Loss

4.3.9 10Gain Control Modes and High Power Amplifier (HPA) Telemetry

4.3.9.1 10Automatic Level Control Mode

4.3.9.2 10Fixed Gain Mode

4.3.10 10DCPR Terminal Phase Noise

4.3.11 10DCPR Transponder NPR

5 11Abbreviations and Acronyms

Contents iii

Page 1 of 11 Printed Monday, February 14, 2022

ID

DCSIRD1

DCSIRD2

DCSIRD3

DCSIRD4

DCSIRD5

DCSIRD6

DCSIRD7

DCSIRD8

DCSIRD9

DCSIRD10

Object Number

1.1

1.1.1

1.1.1.0-1

1.1.2

1.1.2.0-1

1.1.2.0-2

1.1.2.0-3

1.1.2.0-4

1.2

418-XO-IRD-0044, RM Version, Geostationary eXtended Observations (GeoXO) SS to Data Collection System (SS-DCS) Interface

Requirements Document (IRD)

1 Introduction

1.1 General GeoXO Description

1.1.1 Mission Objectives

Primary Mission Objectives:

a) To maintain GOES mission continuity and quality in environmental observations in the 2030-2050 timeframe

b) To provide enhanced environmental data products

c) To improve services and data being provided to Users

d) To be responsive to technology infusion to meet evolving User needs

1.1.2 Mission Description

The mission of the GeoXO System will be to acquire and disseminate environmental data from a near-equatorial Earth orbit at geosynchronous altitude (i.e., a geostationary orbit). This includes the Earth's surface and atmosphere. The major functions of the GeoXO System are to support the Imager (GXI), Lightning Mapper (LMX), Infrared Sounder (GXS), Atmospheric Composition (ACX), Ocean Color (OCX). Another function of the GeoXO System is to support terrestrial and oceanographic Data Collection Platforms (DCPs).

The GeoXO satellite will be launched from Cape Canaveral, FL. The government will be responsible for all ground networks, and communications required for performing the launch and orbit raising activities. All launch and orbit raising activities will be performed from the NOAA Satellite Operations Facility (NSOF) in Suitland, MD. Once geostationary orbit is achieved, all activities will be performed using the Wallops Command and Data Acquisition Station (WCDAS) at Wallops, Virginia as the primary ground station, and a Remote Backup (CBU) facility at Fairmont, West Virginia.

The GeoXO operational constellation will provide coverage from three locations, one at approximately 75° west longitude and the second at 105° west and the third at approximately 137° west longitude. The DCP service will only be supported on the east and west satellites. One or two satellites may be maintained as on orbit spares positioned at approximately 92° west or 94° west longitude. Post launch test and checkout activities will nominally be conducted at 88º west longitude. The satellites may be operated anywhere between 5° west and 148° west. During the transition to the GeoXO satellite series, the operational constellation may contain GOES-R satellites and incumbent satellites that have not yet been de-orbited.

The satellites will be commanded throughout their mission lifetime from the NOAA Satellite Operational Control Center (SOCC) located at NSOF with the ground station radio frequency (RF) interface located at the WCDAS or CBU. The satellite health and safety telemetry streams will be received by the WCDAS/CBU and ground relayed to the SOCC for processing and monitoring. The raw sensor data will be received by the WCDAS/CBU, processed, reformatted, and distributed via NESDIS common cloud framework (NCCF). The WCDAS/CBU also receives all data collection platform reports automatically through the Data Collection Platform Reports (DCPR) transponder.

1.2 DCS Scope

Page 2 of 11 Printed Monday, February 14, 2022

ID

DCSIRD11

DCSIRD12

DCSIRD13

DCSIRD18

DCSIRD19

Object Number

1.2.0-1

1.3

1.3.0-1

1.4

1.4.0-1

418-XO-IRD-0044, RM Version, Geostationary eXtended Observations (GeoXO) SS to Data Collection System (SS-DCS) Interface

Requirements Document (IRD)

The interfaces addressed in this document support the exchange of data between the DCS platforms and the Space Segment (SS) and between the SS and WCDAS/CBU. Only those parameters which are necessary to describe these interface requirements will be referenced.

1.3 Applicable Documents

The following documents form a part of the requirements to the extent specified herein.

1. GOES Data Collection Platform Radio Set (DCPRS) CERTIFICATION STANDARDS at 300 bps and 1200 bps, NOAA/NESDIS (DCPRS) Certification Standards, Version 2.0, June 2009 edition.

2. Manual of Regulations and Procedures for Federal Radio Frequency Management, National Telecommunications and Information Administration (NTIA), September 2017 Revision of the May 2013 Edition.

3. ITU Limits for power flux density from space stations, ITU Radio Regulations, Chapter VI, Article 21, Section 5,2020 Edition.

4. ITU ”Protection criteria used for radio astronomical measurements”, International Telecommunications Union (ITU) Recommendation ITU-R, RA 769-2, 2003 Edition.

5. TC Synchronization and Channel Coding, Blue Book, Issue 1, CCSDS 231.0-B-1, Section 5, September 2003.

1.4 Requirements Terminology

The following requirements terminology is used throughout this document:

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.

The term “(TBR)” means “to be refined/reviewed” for a value that is subject to review for appropriateness and is subject to revision. The vendor is liable for compliance with the information marked “TBR” as if the “TBR” notation did not exist.

The “Spacecraft contractor’s ICD” is synonymous with the RF Spacecraft to ground ICD.

Page 3 of 11 Printed Monday, February 14, 2022

ID

DCSIRD23

DCSIRD24

DCSIRD25

DCSIRD26

DCSIRD27

DCSIRD28

DCSIRD29

DCSIRD30

Object Number

2.0-1

2.0-2

2.0-3

2.0-4

2.0-5

2.0-6

2.0-7

418-XO-IRD-0044, RM Version, Geostationary eXtended Observations (GeoXO) SS to Data Collection System (SS-DCS) Interface

Requirements Document (IRD)

2 DCS Service and Interface Description The GeoXO support to the Data Collection System (DCS) is provided by GeoXO satellites located at approximately 75º west and approximately 137º west longitude. This system provides a one-way link between a large number of DCPs, through the GeoXO satellites to WCDAS, CBU and other ground stations, provided they are within the GeoXO coverage footprint. These DCPs are typically small remote monitoring stations used for the collection and reporting of near real-time environmental data and may be anywhere in the coverage region. DCPs may be located on aircraft, ships, balloons, and fixed sites and collect a wide variety of data (e.g., seismic, water level, wave state, snow and ice cover, etc.). The satellite access methods include either random, or scheduled access.

Messages from the DCP to the WCDAS, CBU, and other ground stations, containing the reported data, are called Data Collection Platform Report (DCPR) messages and use 8- PSK modulation.

The DCPR transponders will have the characteristics of a “bent-pipe architecture,” i.e., the downlink will have the same modulation and formatting as the uplink, regardless of the modulation used. The DCPR uplink is UHF and the downlink is L-Band. The DCPR transmissions are timed and randomly scheduled channelized frequency division multiple access (FDMA) with a total bandwidth of 400 kHz available. The DCPR channel center frequencies are given in applicable document [1].

The first 300 kHz is for domestic service. The 300 kHz is channelized and can be divided into 400, 300 bit/s (data) services with a channel bandwidth of 750 Hz, and into channels for 1200 bit/s (data) service with a channel bandwidth of 2250 Hz.

The upper 100 kHz consists of 132 channels with a 750 Hz bandwidth that are assigned to the International Data Collection System (IDCS) service.

Section 3 defines the overall link performance required for DCPR.

Section 4 defines the DCPR interface.

Page 4 of 11 Printed Monday, February 14, 2022

ID

DCSIRD31

DCSIRD32

DCSIRD33

DCSIRD34

DCSIRD35

DCSIRD36

DCSIRD37

DCSIRD38

DCSIRD39

DCSIRD40

DCSIRD41

DCSIRD42

DCSIRD43

DCSIRD44

DCSIRD45

DCSIRD46

DCSIRD47

DCSIRD48

DCSIRD49

DCSIRD50

Object Number

3.0-1

3.0-2

3.1

3.1.0-1

3.2

3.2.0-1

3.3

3.3.0-1

3.4

3.4.0-1

3.5

3.5.0-1

3.6

3.6.0-1

3.7

3.7.0-1

3.8

3.8.0-1

3.9

418-XO-IRD-0044, RM Version, Geostationary eXtended Observations (GeoXO) SS to Data Collection System (SS-DCS) Interface

Requirements Document (IRD)

3 DCS RF Interface Performance Requirements The DCPR link shall meet performance requirements when the spacecraft is in the operational mode.

This section provides the interface requirements for the DCPR service.

3.1 Simultaneous Links

All services shall meet their performance requirements simultaneously with the operation of all other GeoXO services.

3.2 NTIA Compliance

The DCPR communication link shall comply with all NTIA requirements for geostationary spacecraft operating at UHF, L, S, and X-Band frequencies. [Applicable Document 2].

3.3 Power Flux Density Limits

The downlink Power Flux Density (PFD) values for the DCPR link shall conform to the ITU regulations RR21 that pertain to L -Band transmissions [Applicable Document 3] and be incorporated into the spacecraft contractor's ICD.

3.4 Radio Astronomy Band Protection

The DCPR Effective Isotropically Radiated Power (EIRP) values shall protect the radio astronomy band from 1660 to 1670 MHz so that the spectral power flux density in this band at the surface of the Earth will be -266 dB W/(m2 Hz) [Applicable Document 4].

3.5 Long Term Frequency Stability

The DCPR long term frequency translation error due to the satellite shall be less than ±

0.1 ppm under all conditions over the life of the spacecraft.

3.6 Short Term Frequency Stability

The DCPR short term frequency translation error due to the spacecraft shall be less than 1x10-11 for one second and 1x10-10 for ten seconds.

3.7 Spacecraft Phase Noise

The phase noise added to the DCPR service by the spacecraft shall be < 1.5° RMS from 2 Hz to a frequency equal to the modulation symbol rate.

3.8 DCPR Unwanted Emissions

The unwanted emissions from the DCPR downlink shall not exceed the levels specified in Part 5.6 of Applicable Document 2.

3.9 Spacecraft Intermodulation

Page 5 of 11 Printed Monday, February 14, 2022

ID

DCSIRD51

Object Number

3.9.0-1

418-XO-IRD-0044, RM Version, Geostationary eXtended Observations (GeoXO) SS to Data Collection System (SS-DCS) Interface

Requirements Document (IRD)

If multiple GeoXO services pass through the same amplifying module, the intermodulation products that fall within any transmission channel shall be at least 30 dB below the desired signal levels when tested with unmodulated signals that are 3 dB below their dynamic range maximum and anywhere in their channel bandwidth.

Page 6 of 11 Printed Monday, February 14, 2022

ID

DCSIRD52

DCSIRD53

DCSIRD54

DCSIRD55

DCSIRD56

DCSIRD57

DCSIRD58

DCSIRD59

DCSIRD60

DCSIRD61

Object Number

4.0-1

4.0-2

4.1

4.1.0-1

4.1.1

4.1.1.0-1

4.1.1.0-2

4.1.2

4.1.2.0-1

418-XO-IRD-0044, RM Version, Geostationary eXtended Observations (GeoXO) SS to Data Collection System (SS-DCS) Interface

Requirements Document (IRD)

4 DCPR RF Interface Performance Requirements This section describes DCPR uplink and downlink requirements.

The DCPR service shall simultaneously meet all of its requirements under worst case operational conditions over the life of the satellite, at edge of coverage, and over the full dynamic uplink power range.

4.1 General DCPR Requirements

This section provides requirements that apply to both uplinks and downlinks.

4.1.1 DCPR Requirements Summary

This section describes general DCPR uplink and downlink link requirements.

The DCPR data link requirements are summarized in Table DCSIRD59.

Table DCSIRD59: DCPR Link Requirements

DCPR Uplink Transmit Requirement Center frequency Domestic: 401.900 MHz

International:402.200 MHz

EIRP

300 bps 37 to 41 dBm 1200 bps 43 to 47 dBm

Polarization RHCP Modulation and Information data rate*

8-PSK, 300 and 1200 bps

Coding Rate 2/3 trellis coding Format NRZ-M Channel bandwidth Domestic or International: fc ± 200 kHz Data Collection Platform elevation angle

> 5 degrees

Satellite Receive Minimum receive G/T Contractor specified (dB/K) Uplinks capacity Equivalent to 500 TBR signals at 41 TBR dBm

Satellite Transmit Center frequency Domestic: 1691.9 MHz

International: 1692.2 MHz EIRP TBD (dBm) Antenna Coverage To WCDAS and CBU Polarization linear N-S polarization BER 1 x 10-6

Ground Receive Polarization Linear Ground receive G/T 15 dB/K Geographic Footprint Within TBD km of the great circle arc between

WCDAS and CBU

4.1.2 Link Margin Requirement

The spacecraft shall provide a link margin of 2 dB for the DCPR link over the life of the satellite and over the coverage.

Page 7 of 11 Printed Monday, February 14, 2022

ID

DCSIRD62

DCSIRD63

DCSIRD64

DCSIRD65

DCSIRD66

DCSIRD67

DCSIRD68

DCSIRD69

DCSIRD70

DCSIRD71

DCSIRD72

DCSIRD73

DCSIRD74

DCSIRD75

DCSIRD76

DCSIRD77

DCSIRD78

DCSIRD79

DCSIRD80

Object Number

4.1.3

4.1.3.0-1

4.2

4.2.0-1

4.2.1

4.2.1.0-1

4.2.2

4.2.2.0-1

4.2.2.0-2

4.2.3

4.2.3.0-1

4.2.4

4.2.4.0-1

4.2.5

4.2.5.0-1

4.2.6

4.2.6.0-1

4.2.7

4.2.7.0-1

418-XO-IRD-0044, RM Version, Geostationary eXtended Observations (GeoXO) SS to Data Collection System (SS-DCS) Interface

Requirements Document (IRD)

4.1.3 DCPR End-to-End BER

The BER shall be less than 1x 10-6 after decoding.

4.2 Uplink DCPR RF Interface Requirements

This section describes the ground to spacecraft (uplink) requirements.

4.2.1 Uplink Center Frequency and Frequency Stability

The spacecraft shall meet all of its performance requirements for DCPR uplinks received in a 400 kHz bandwidth centered at 401.900 MHz (Domestic band) or 402.200 MHz (International band) and maintained to one part in 108.

4.2.2 Uplink EIRP and Capacity

The spacecraft shall meet all of its performance requirements for 500 DCPR uplinks at an average uplink EIRP of 41 dBm, and at least one 300 bps signal at 37 dBm and at least one 1200 bps signal at 43 dBm at any frequency in the transponder passband.

The spacecraft shall meet all of its performance requirements when the 300 bps signals are between 37 and 41 dBm and the 1200 bps signals are between 43 and 47 dBm.

4.2.3 Uplink G/T

The value for the spacecraft Gain-to-Noise Temperature Ratio (G/T) to meet the performance requirements shall be determined by the spacecraft contractor and incorporated into the spacecraft contractor's ICD.

4.2.4 Uplink Polarization

The spacecraft shall meet all of its performance requirements for DCPR uplinks with RHCP polarization to a spacecraft antenna with RHCP polarization.

4.2.5 Uplink Atmospheric Loss

The spacecraft shall meet all of its performance requirements with an atmospheric attenuation loss of 0.7 dB on the uplink (based on 99.99% one-way annual availability including scintillation).

4.2.6 Uplink Polarization Loss

The spacecraft shall meet all of its performance requirements with a polarization loss from the DCPR antenna of 0.0 dB as this loss is included in the EIRP uplink specification.

The worst case Axial Ratio is 6.0 dB as specified in the DCPRS Certification document [Applicable Document 1].

4.2.7 Uplink Pointing Loss

The spacecraft shall meet all of its performance requirements with a pointing loss 0.0 dB for the DCPR uplink as the EIRP specification includes this loss. The satellite receive pointing loss will be determined by the contractor and incorporated into the spacecraft contractor's ICD.

Page 8 of 11 Printed Monday, February 14, 2022

ID

DCSIRD81

DCSIRD82

DCSIRD83

DCSIRD84

DCSIRD85

DCSIRD86

DCSIRD87

DCSIRD88

DCSIRD89

DCSIRD90

DCSIRD91

DCSIRD92

DCSIRD93

DCSIRD94

DCSIRD95

DCSIRD96

Object Number

4.2.8

4.2.8.0-1

4.2.9

4.2.9.0-1

4.2.10

4.2.10.0-1

4.2.11

4.2.11.0-1

4.2.12

4.2.12.0-1

4.2.13

4.2.13.0-1

4.2.14

4.2.14.0-1

4.2.15

4.2.15.0-1

418-XO-IRD-0044, RM Version, Geostationary eXtended Observations (GeoXO) SS to Data Collection System (SS-DCS) Interface

Requirements Document (IRD)

4.2.8 Forward Error Correction

The spacecraft shall meet all of its performance requirements for 8-PSK DCPR uplinks with convolutional trellis code, rate 2/3 with constraint length 7. The DCPR uplinks are described in Applicable Document 1.

4.2.9 Uplink Data Rates

The spacecraft shall meet all of its performance requirements for the 8-PSK DCPR uplinks with information rate 300 or 1200 bps (transmitted rate after coding is 450 or 1800 bps). The associated symbol rate is 150 or 600 sps.

4.2.10 Uplink Modulation

The spacecraft shall meet all of its performance requirements for DCPR uplinks with 8- PSK modulation for 300 and 1200 bps signals.

4.2.11 Uplink Format

The spacecraft shall meet all of its performance requirements for DCPR uplinks with an NRZ-L format.

4.2.12 Uplink Phase Noise

The spacecraft shall meet all of its performance requirements for a DCPR uplink with a phase noise of less than 2.5° RMS when integrated from 2 Hz to a frequency equal to the modulation symbol rate.

4.2.13 Spacecraft Receive Coverage

The spacecraft shall meet all of its performance requirements for DCPR uplinks for all Data Collection Platforms with an antenna elevation angle >5°.

4.2.14 Rejection of Out of Band Signals

The DCPR transponder shall have a 20 dB rejection of all signals greater than 40 KHz from the band edges.

4.2.15 Transponder Intermediate Frequency Filtering

Requirements

The DCPR transponder shall filter the IF signals according to Table DCSIRD96.

Table DCSIRD96: Transponder Intermediate Frequency Filtering Requirements

Rejection (dB) Condition Offset from Center

Freq (kHz) 1 > +/- 200 20 < +/- 240 40 < +/- 500 50 < +/- 800

Page 9 of 11 Printed Monday, February 14, 2022

ID

DCSIRD97

DCSIRD98

DCSIRD99

DCSIRD100

DCSIRD101

DCSIRD102

DCSIRD103

DCSIRD104

DCSIRD105

DCSIRD106

DCSIRD107

DCSIRD108

DCSIRD109

DCSIRD110

DCSIRD111

DCSIRD112

DCSIRD113

DCSIRD114

Object Number

4.3

4.3.0-1

4.3.1

4.3.1.0-1

4.3.2

4.3.2.0-1

4.3.3

4.3.3.0-1

4.3.4

4.3.4.0-1

4.3.5

4.3.5.0-1

4.3.6

4.3.6.0-1

4.3.7

4.3.7.0-1

4.3.8

4.3.8.0-1

418-XO-IRD-0044, RM Version, Geostationary eXtended Observations (GeoXO) SS to Data Collection System (SS-DCS) Interface

Requirements Document (IRD)

4.3 Downlink DCPR Interface Requirements

This section describes the spacecraft to ground (downlink) requirements. The DCPR downlink will be received by the WCDAS/CBU and other ground terminals within the GeoXO antenna footprint.

4.3.1 Downlink Center Frequency

The spacecraft shall meet all of its performance requirements when transmitting to WCDAS and CBU receivers with a center frequency of 1691.900 and 1692.200 MHz for the domestic and international bands respectively.

4.3.2 Ground Antenna G/T and Spacecraft EIRP

The ground station antennas have a clear sky G/T (at 5° elevation angle) of 15.0 dB/K or greater. The EIRP required to meet all performance requirements when transmitting to ground antennas shall be determined by the contractor and incorporated into the spacecraft contractor's ICD.

4.3.3 Spacecraft Transmit Coverage

The spacecraft shall meet all of its performance requirements when transmitting to WCDAS, and CBU.

4.3.4 DCPR Downlink Polarization

The contractor shall select the spacecraft transmit polarization and incorporate this into the spacecraft contractor's ICD.

4.3.5 DCPR Receive Eb/No

The spacecraft shall meet all of its performance requirements when transmitting to WCDAS and CBU receivers which require an Eb/No of 11.0 dB (including ground implementation loss but not including spacecraft implementation loss) to meet the required BER.

4.3.6 Downlink Atmospheric Loss

The spacecraft shall meet all of its performance requirements with a downlink atmospheric attenuation loss of 2.5 dB (based on 99.99% one-way annual availability including scintillation).

4.3.7 Downlink Pointing Loss

The satellite transmit pointing loss shall be determined by the contractor and incorporated into the spacecraft contractor's ICD.

4.3.8 Downlink Polarization Loss

The downlink polarization loss shall be determined by the contractor and incorporated into the spacecraft contractor's ICD.

Page 10 of 11 Printed Monday, February 14, 2022

ID

DCSIRD115

DCSIRD116

DCSIRD117

DCSIRD118

DCSIRD119

DCSIRD120

DCSIRD121

DCSIRD122

DCSIRD123

DCSIRD124

DCSIRD125

DCSIRD126

DCSIRD127

DCSIRD128

DCSIRD129

DCSIRD130

Object Number

4.3.9

4.3.9.0-1

4.3.9.0-2

4.3.9.0-3

4.3.9.1

4.3.9.1.0-1

4.3.9.1.0-2

4.3.9.1.0-3

4.3.9.1.0-4

4.3.9.1.0-5

4.3.9.2

4.3.9.2.0-1

4.3.10

4.3.10.0-1

4.3.11

4.3.11.0-1

418-XO-IRD-0044, RM Version, Geostationary eXtended Observations (GeoXO) SS to Data Collection System (SS-DCS) Interface

Requirements Document (IRD)

4.3.9 Gain Control Modes and High Power Amplifier (HPA)

Telemetry

The DCPR link shall have two gain control modes, an Automatic Level Control (ALC) mode and a fixed gain mode.

The gain control modes shall be selectable by ground command.

Critical DCPR HPA telemetry shall be provided to the ground operators via the telemetry downlink in order to determine the health of the flight HPAs and for diagnostics. The critical HPA telemetry list will be provided in the spacecraft contractor’s ICD.

4.3.9.1 Automatic Level Control Mode

The DCPR ALC shall produce an output power at the operational level with no additional uplink except thermal noise.

The DCPR ALC shall maintain output power to within 1 dB peak-to-peak over the life of the satellite from a minimum of two inputs at 41 dBm to a maximum of 500 inputs at 41 dBm. To meet this requirement ground commanded gain compensation to adjust for life time changes (e.g., temperature and aging) is permitted.

The DCPR ALC when driven by a step increase in the input power level corresponding to a step from minimum drive necessary for measurement to any and all drive levels up to the dynamic range maximum, the amplitude and phase responses of the repeater shall be within ± 1.0 dB and ±3 of steady state values within 10 ms.

The DCPR ALC, when driven by a step decrease in the input power level corresponding to a step from the dynamic range maximum to the lowest drive level sufficient to measure the phase noise, the amplitude and phase responses of the repeater shall be within ± 1.0 dB and ±3 of steady state values in 250 - 450 ms.

The DCPR ALC mode shall be commandable with step resolution less than or equal to

0.5 dB over the dynamic range.

4.3.9.2 Fixed Gain Mode

The DCPR fixed gain mode shall be commandable with step resolution less than or equal to 1.5 dB over the dynamic range.

4.3.10 DCPR Terminal Phase Noise

The spacecraft shall meet all of its performance requirements when transmitting to a ground receiver in the antenna footprint with less than 2° RMS of phase noise when integrated from 2 Hz to a frequency equal to the modulation symbol rate.

4.3.11 DCPR Transponder NPR

The DCPR transponder noise power ratio (NPR) shall be at least 25 dB.

Page 11 of 11 Printed Monday, February 14, 2022

ID

DCSIRD131

DCSIRD132

Object Number

5.0-1

418-XO-IRD-0044, RM Version, Geostationary eXtended Observations (GeoXO) SS to Data Collection System (SS-DCS) Interface

Requirements Document (IRD)

5 Abbreviations and Acronyms ALC Automatic Level Control BER Bit Error Rate bps Bits Per Second BPSK Binary Phase Shift Keying CBU Consolidated Backup CDMA Code Division Multiple Access DCP Data Collection Platform DCPR Data Collection Platform Report DCPRS Data Collection Platform Radio Set DCS Data Collection System Eb/N0 Energy per bit to noise density ratio EIRP Effective Isotropically Radiated Power FDMA Frequency Division Multiple Access FEC Forward Error Correction GeoXO Geostationary and eXtended Orbits GOES Geostationary Operational Environmental Satellite G/T Gain-to-Noise Temperature Ratio (dB/K) GXI Imager GXS Sounder HPA High Power Amplifier ICD Interface Control Document IDCS International Data Collection System IRD Interface Requirements Document ITU International Telecommunications Union L-Band 1.0 - 2.0 GHz Frequency Band MHz 1 x 106 Hertz NOAA National Oceanic and Atmospheric Administration NPR Noise Power Ratio NSOF NOAA Satellite Operations Facility NTIA National Telecommunications and Information Agency OCX Ocean Color ORTT&C Orbit Raising, Tracking, Telemetry, and Command PFD Power Flux Density ppm parts per million PSK Phase Shift Keying RA Radio Astronomy RF Radio Frequency RHCP Right Hand Circularly Polarized RMS Root Mean Square RR Radio Regulation S-Band 2 - 4 GHz Frequency Band SOCC Satellite Operations Control Center sps Symbols Per Second SS Space Segment WCDAS Wallops Command and Data Acquisition Station

Effective Date: February 10, 2022 418-XO-IRD-0044

Document Change Record (DCR)

CCR GEO-XO#: X00054 Rev: Title: 418-XO-IRD-0044: baseline GeoXO_SS-DCS Contract # N/A GOES S/C: GeoXO Effectivity: SC CCB Status: Approved Doc #: 418-XO-IRD-0044 CCB Date: 02/10/2022 Doc Version: 1.0 Contract Mod#: N/A DOORs Version: 1.0 Doc Change Date: Feb. 10, 2022 DOORs ID #: 1.0