ICESat Flight Dynamics Detailed Requirements and Specification

Draft September 2, 1999

#  {#section .unnumbered}

# Scope

This document describes the requirements for the Flight Dynamics System
(FDS) of the ICESat Mission Operations Center (MOC). The FDS will be
that part of the MOC which provides overall Guidance & Navigation (G&N)
for the ICESat mission.

# Applicable Documents

The following are reference documents:

a.  ICESat Mission Systems Requirements Document, February, 1998.

b.  ICESat Mission Operations Requirements Document (MORD), Draft,
    Version 1.0.

c.  ICESat Space-Ground Data Interface Control Document, December, 1998.

d.  ICESat Space-Ground Radio Frequency Interface Control Document,
    December, 1998.

e.  EOS Ground System Architecture Description Document, September,
    1997.

f.  ICD between the EDOS and the EOS Ground System (EGS) Elements,
    Final, August 9, 1996, GSFC/MO&DSD, 510-ICD-EDOS/EGS

g.  Spacecraft Operations Description Manual for the ICESat Observatory,
    December, 1998 (draft).

# System Requirements

## NASA Provided Flight Dynamics Services

The FDS shall be capable of ingesting and utilizing the following data
and services provided by NASA GSFC Multi-Mission Flight Dynamics (MMFD).
MMFD will support the FDS and will include the launch and early orbit
(L&EO) support traditionally provided by MMFD for other satellite
projects. The MMFD will interface with the FDS for this L&EO support for
nominally three weeks after launch.

a.  Work with NASA ground stations to analyze and verify tracking system
    accuracy.

b.  Serve as the interface to the launch contractor for acquiring and
    processing launch trajectory predicts and initial post-separation
    spacecraft orbit predicts.

c.  Acquire and process Launch Trajectory Ascent System (LTAS) data and
    Redundant Inertial Flight Control Assembly (RIFCA) data from the
    launch site to generate the initial orbit predict.

d.  Acquire NORAD tracking data and process to generate orbit predicts.

e.  Acquire Universal Tracking Data Format (UTDF) angles tracking data
    from NASA ground stations after passes and process into orbit
    predicts.

f.  Generate initial orbit predict after spacecraft separation and
    distribute it as an IIRV to the DSN, MOC (FDS), and WOTIS for use by
    the ground stations.

g.  Generate updated orbit predicts as needed for the first 24 hours
    after launch with the first delivery occurring between L+4 and L+6
    hours. Each update will be distributed to the DSN, MOC (FDS), and
    WOTIS for use by the ground stations.

h.  Generate updated orbit predicts every 24 hours for the first one to
    three weeks after launch (as needed) and distribute them to the DSN,
    MOC (FDS), and WOTIS for use by the ground stations.

i.  Orbit Determination based on angle data from the ground tracking
    stations (if GPS data is not available).

j.  Consultation for maneuver and trajectory planning.

## Mission Characteristics

FDS shall be capable of supporting the ICESat mission with the following
characteristics.

a.  Inclination = 94 degrees.

b.  Altitude = 600 km.

c.  Orbit = non-sun synchronous frozen orbit.

d.  2 repeat orbits (183 days during mission and 8 days during
    calibration).

e.  +/- 800 meter groundtrack control at all latitudes.

### Raw Data Latency 

The FDS shall be capable of functioning with the following data latency:

a.  X-band data packets that contain GPS raw data shall be available via
    EDOS at the FDS no later than 6 hours after the X-band ground
    station contact is completed.

b.  S-band real-time data, including GPS on-board solutions data, shall
    be available via the EPGS and WFF at the FDS within 1 minute of the
    end of the ground station contact.

c.  S-band playback data shall be available at the FDS via EDOS within
    30 minutes of the end of the ground station contact.

## Software, Hardware, Personnel, and Facilities

### Software and Hardware

The contractor shall provide all FDS software development and
maintenance and all hardware systems and training required to operate
the software for the life of the mission.

### Personnel and Facilities

The contractor shall provide all FDS personnel and facilities required
to operate the flight dynamics systems for the life of the mission.

## Mission Phases Support

### Maneuver Constraints

#### High Latitudes

No maintenance maneuvers shall occur over Antarctica or at points above
60 degrees latitude that are coincident with Greenland over-flights
except in special or emergency circumstances.

#### Single Maneuver

Groundtrack maintenance shall be performed using only one maneuver when
possible.

#### Frozen Orbit Maintenance

Frozen orbit maintenance shall be done in conjunction with the ground
track maintenance maneuver.

#### Maneuver Frequency

Maneuvers shall be constrained to occur no more frequently than once
daily to support the Precision Orbit Determination (POD).

### Pre-Launch Phase

The pre-launch period will cover all time up to separation from the
launch vehicle.

#### Mission Analysis and Delta-V Budget

The FDS shall provide mission analysis and delta velocity (Delta V)
budget calculation and analysis.

#### Injection Orbit Selection

The FDS shall provide injection orbit selection analysis.

#### Reentry Analysis

The FDS shall provide reentry (lifetime) analysis.

#### Ground Station Coverage Analysis

The FDS shall provide ground station coverage analysis.

#### Launch Window

The FDS shall provide launch window analysis.

#### Operations Planning

The FDS shall provide operations planning, including participation in
launch rehearsals and simulations.

### Checkout Phase

The Checkout period is the time from launch vehicle separation to the
time the spacecraft bus has been accepted by the government
(approximately 30 days).

#### Separation Vector

The FDS shall ingest and process launch vehicle separation vector from
GFDS.

#### Planning and Calibration -- Orbit Raising

The FDS shall provide planning and calibration for all orbit raising
maneuvers.

#### Planning and Calibration -- Orbit Maintenance

The FDS shall provide planning and calibration for all routine
groundtrack maintenance maneuvers.

#### Planning and Calibration \-- Inclination

The FDS shall provide planning and calibration for inclination
maneuvers.

#### Thruster Calibration -- Orbit Attainment

The FDS shall provide thruster calibration for the orbit attainment
maneuvers.

#### Thruster Calibration -- Orbit Maintenance

The FDS shall provide thruster calibrations for the orbit maintenance
maneuvers.

#### Orbit Determination and Prediction

The FDP shall provide orbit determination and prediction based on GPS
data from the flight receiver.

#### On-board Attitude Verification

The FDS shall support on-board attitude validation.

#### Anomaly Resolution

The FDS shall support anomaly resolution.

#### Sensor Calibration

The FDS shall support sensor calibration.

#### Provide IIRVs

The FDS shall provide orbit predictions in Improved Inter-Range Vector
(IIRV) format to the ground station network daily.

#### Convert Maneuver Plan

The FDS shall convert the maneuver plan into commands and table uploads
for uplink to spacecraft within 1 hour of receipt of the maneuver plan.

### Calibration and Validation Phase

The Calibration and Validation period covers all time from acceptance of
the spacecraft by the government to the time that the GLAS instrument
has been calibrated and validated and science data gathering begins.

#### Planning and Calibration

The FDS shall provide planning and calibration of the inclination and
groundtrack maintenance maneuvers.

#### On-board Orbit and Attitude Determination

The FDS shall support validation of the onboard orbit and attitude
determination.

#### Anomaly Resolution

The FDS shall support anomaly resolution.

#### Sensor Calibration

The FDS shall support sensor calibration.

#### Generation of Planning Data

The FDS shall generate planning and scheduling data products for use by
the MOC daily.

#### Provide IIRVs

The FDS shall provide orbit predictions in Improved Inter-Range Vector
(IIRV) format to the ground station network daily.

#### Convert Maneuver Plan

The FDS shall convert the maneuver plan into commands and table uploads
for uplink to spacecraft within 1 hour of receipt of the maneuver plan.

### Maneuver Planning

The contractor shall provide maneuver planning and maneuver calibration
for all phases of mission operations. The effect of these maneuvers on
the mean orbit elements and groundtrack offset shall be predicted and
communicated to the MOC.

#### Drag Make-Up Maneuvers

The FDS shall be capable of designing along track maneuvers to adjust
the orbit semi-major axis to change the groundtrack drift rate relative
to the exact repeat orbit.

#### Inclination Maneuvers 

The FDS shall be capable of designing across track maneuvers to adjust
the orbit inclination to change the groundtrack offset at high latitudes
relative to the exact repeat orbit.

#### Orbit Change Maneuvers

The FDS shall be capable of designing two along track maneuvers to
adjust the orbit semi-major axis to switch between the calibration and
mission orbits.

### Groundtrack Monitoring and Prediction

#### Groundtrack Monitoring

The groundtrack shall be monitored daily and compared to that of the
calibration or mission orbit, whichever is appropriate. Such monitoring
shall be valid for all latitudes.

#### Groundtrack Prediction

The groundtrack evolution shall be predicted daily to aid in maneuver
planning. Such predictions shall make use of solar activity predictions
to anticipate atmospheric drag, and the effect of luni-solar gravity on
the orbit inclination.

#### Output

The output for groundtrack monitoring and prediction shall consist of
both a graphical display of predicted groundtrack offset, and tables of
predicted mean orbit element and groundtrack offset evolution.

### Mission Planning Support

#### Real-Time Attitude

The FDS shall determine coarse real-time ICESat attitude.

#### Mission Planning

The FDS shall provide mission planning aids.

#### Attitude Sensor Monitoring

The FDS shall provide attitude sensor hardware performance monitoring.

#### Predict Ephemeris and Maneuver Planning

The FDS shall predict the ICESat orbit ephemeris and perform maneuver
prediction and planning.

#### Maneuver Monitoring

The FDS shall provide near-real-time maneuver monitoring (temperature,
pressure, etc.).

#### Acquisition Data 

The FDS shall provide acquisition data products.

#### Post-Maneuver State

The FDS shall assess the post-maneuver spacecraft state.

## Orbit & Attitude Determination

### Operational Orbit Determination

The FDS shall provide Operational Orbit Determination (OOD) using GPS
data from the flight receiver in combination with GPS data from a
worldwide network of ground tracking sites.

#### Operational Orbit Determination Accuracy

The OOD solutions shall be generated each day for orbit monitoring and
maneuver planning.

##### Along Track Position

The orbit solution along track position accuracy shall be 5 meters (1
sigma).

##### Across Track Position

The orbit solution across track position accuracy shall be 5 meters (1
sigma).

##### Radial Position

The orbit solution radial position accuracy shall be 1 meter (1 sigma).

##### Solution Latency

The orbit solution shall be available within 2 hours after X-band data
is received at the FDS.

##### Comparison with POD

FDS shall compare the OOD with the POD generated by the ST on a periodic
basis in support of the onboard GPS validation.

#### Propagation Accuracy -- Without Maneuver

The FDS shall propagate each daily OOD solution into the future for
groundtrack monitoring and maneuver planning. The following requirements
shall apply after one day of propagation which does not include a
maneuver.

##### Along Track Position

The along track position accuracy of the OOD propagation shall be 1.0
kilometer (1 sigma).

##### Across Track Position

The across track position accuracy of the OOD propagation shall be 10
meters (1 sigma).

##### Radial Position

The radial position accuracy of the OOD propagation shall be 10 meters
(1 sigma).

##### Propagation Latency

The orbit propagation shall be available within 2 hours after X-band
data received at the FDS.

#### Propagation Accuracy -- With Maneuver

The FDS shall propagate each daily OOD solution into the future for
communication antenna pointing. The following requirements shall apply
after one day of propagation after a maneuver.

##### Along Track Position

The along track position accuracy of the OOD propagation shall be 4.0
kilometer (1 sigma).

##### Across Track Position

The across track position accuracy of the OOD propagation shall be 4.0
kilometers (1 sigma).

##### Radial Position

The radial position accuracy of the OOD propagation shall be 4.0
kilometers (1 sigma).

##### Propagation Latency

The orbit propagation shall be available within 2 hours after X-band
data received at the FDS.

### Operational Attitude Support

#### Off-Nadir Pointing Monitoring

The FDS shall monitor off-nadir pointing calculations and performance,
using algorithms supplied by the University of Colorado.

#### Off-Nadir Pointing Quaternion Generation

The FDS shall generate the off-nadir pointing quaternions by running the
off-nadir pointing algorithm provided by the University of Colorado, and
provide them to the MOC for upload to the spacecraft each day. The
quaternions shall be available within one hour of the receipt of the OOD
solution.

## Sensor Support

The contractor shall provide for the operation, maintenance, and
calibration of various sensors used on the spacecraft.

### Sensor Uploadable Parameters Support

The spacecraft contractor (Ball Aerospace) will provide periodic updates
for the following sensors and subsystems.

#### Star Tracker

These requirements apply to the bus star tracker. GSFC will provide
updates for the GLAS star tracker.

##### Proper Stellar Motion

The FDS shall support updates of the spacecraft bus star tracker star
catalog with respect to proper stellar motion (estimated annual upload
of approximately 50 stars).

##### Star Precession

The FDS shall support updates of the spacecraft bus star tracker star
precession quaternion (estimated weekly upload).

#### GPS Initial Condition Vector

The FDS shall support calculation and upload of an Initial Conditions
Vector for initialization of the GPS receiver whenever a Spacecraft
Control Computer (SCC) reset takes place.

#### Magnetic Field 

The FDS shall support updates of the onboard magnetic field tables
(table upload approximately annually).

### Sensor Calibration Support

#### Star Tracker and IRU

The FDS, with support from the spacecraft contractor (Ball Aerospace)
and science operations, shall participate in calibration of the
alignments of the Solid State Star Tracker (SSST), and Inertial
Reference Units (IRU).

#### Star Tracker FOV

The FDS, with support from the spacecraft contractor (Ball Aerospace)
and science operations, shall participate in calibration of the
star-tracker's field-of-view (FOV) calibration coefficients.

#### IRU Scale Factors and Rate Drift

The FDS, with support from the spacecraft contractor (Ball Aerospace)
and science operations, shall participate in calibration of the IRU
scale factors and drift rate biases (3-axis calibration at varying
rates).

## Products Exchange

### FDS Products to the Mission Operations Center

#### Orbit Solutions

The FDS shall generate both Operational Orbit Determination and
propagated state vectors at least daily for use by the MOC on a routine
basis for all phases of the mission.

#### Maneuver Design

The FDS shall generate maneuver design data (magnitude, attitude, and
time) for use by the MOC on a routine basis for all phases of the
mission.

#### Groundtrack Offset

The FDS shall generate plots and tables of the groundtrack offset
(actual and predicted versus time) each day for use by the MOC on a
routine basis for all phases of the mission.

#### Frozen Orbit Parameters

The FDS shall generate plots and tables to monitor the frozen orbit
(including inclination, eccentricity, and argument of perigee) each day
for use by the MOC on a routine basis for all phases of the mission.

#### Initial Condition Vector

The FDS shall generate initial condition vectors for the SCC and/or GPS,
as needed, for use by the MOC on a routine basis for all phases of the
mission.

#### Base Time Load

The FDS shall generate the base time load to correlate the spacecraft
clock (clock correlation code) for use by the MOC on a routine basis for
all phases of the mission.

#### Orbit and Attitude Verification

The FDS shall provide support for orbit and attitude verification.

### MOC Products to the Flight Dynamics System

#### Propulsion Data

The FDS shall be capable of ingesting and using propulsion system data,
including tank pressure and temperature. The spacecraft contractor (Ball
Aerospace) will provide the equations for the propulsion and the
spacecraft mass models.

#### All S-Band Data

The FDS shall be capable of obtaining by electronic file transfer all
raw S-band real-time and playback data received and all products
generated by the MOC.

#### Solar Array Encoder Data

The FDS shall be capable of obtaining the solar array encoder
conversions from the MOC.

### Flight Dynamics Products to the Science Team

#### Inertia and Mass Properties

The FDS shall make spacecraft inertia and mass properties available to
the science team when these items change significantly.

#### Maneuver Plans

The FDS shall make maneuver magnitudes and timelines available to the
science team within 1 hour after each maneuver design.

#### OOD Solutions

The FDS shall make OOD solutions available to the science team daily.

#### Star Tracker Data

The FDS shall make CT-602 star tracker data available to the science
team.

### Data and Products Archive

#### Permanent Archive

The FDS shall permanently archive all data received and products
generated by FDS for the life of the mission. In particular, all orbit
elements and propulsion data shall be permanently archived.

#### Archive Accessibility

All data archives shall be readily accessible (via File Transfer
Protocol, etc.) by authorized users external to the FDS for the life of
the mission.

## Reliability

### Availability

The FDS shall be designed for an availability that meets the operational
requirements set forth in the Mission Operations Performance
Specification.

### Single Point Failures

The FDS shall be designed to minimize the occurrence and effects of
single point hardware or software failures.

### Maintenance

FDS maintenance shall be scheduled during non-contact times and shall be
conducted on a non-operational functional string to ensure that a
functioning string is always available to support operations.

## Security

### Physical Security

The FDS shall be located with the MOC and secured from unauthorized
access.

### Computer Systems

The FDS computer systems and supporting network interfaces shall be
protected from unauthorized access.

### Databases

The FDS flight database access and updates shall be controlled.

### Backups

Security measures shall be taken to prevent database corruption and
permanent database loss. At a minimum, a backup copy of all changed
software, databases, and documentation shall be retained in a separate
physical location other than the MOC.

## Integration and Testing Support

The FDS shall participate in all relevant ground system simulations and
rehearsals, including science data flow tests.

## Documentation

The FDS shall be described by the following documents. If existing
documentation used on other missions currently exist, these may be used
in lieu of the listed documents provided they contain all the necessary
information. The FDS documentation may be combined with similar MOC
documentation.

### Interface Control Document

A FDS External Interface Control Document shall describe the FDS
external interfaces.

### Specification

A FDS Detailed Requirements and Specification shall describe required
FDS performance.

### Test Plan

A FDS Test Plan shall describe the verification of FDS performance.

### Operations Handbook

A FDS Operations Procedures Handbook shall describe both nominal and
contingency FDS operations.

### Operational Agreements

The FDS shall have in place operational agreements with other mission
elements such as FOT, IOT, ST, and EPGS.

## Reviews

### PDR

The FDS shall pass a Preliminary Design Review during August of 1999.

### CDR

The FDS shall pass a Critical Design Review during December of 1999.
This review will be held in conjunction with the MOC CDR.

# Verification

## General

Compliance of the FDS with the requirements of Section 3 shall be
verified by a planned series of functional tests, inspections, analyses,
and demonstrations. To build confidence in the FDS, the verification
efforts shall commence at the component or configuration level, and
proceed to the system level. System level, end-to-end tests shall be
performed prior to and during mission operation rehearsals.

## Responsibility for Verification

### Configuration Level

Suppliers of COTS or modified COTS software components shall be
responsible for verification that those components meet the appropriate
requirements of Section 3.

### System Level

The FDS integrator shall be responsible for verification that the system
meets the requirements of Section 3.

### Compliance Matrix

Table 4.1 lists the verification method to be used for every requirement
of Section 3. The verification methods are Inspection (I), Analysis (A),
Test (T), and Demonstration (D).

Table 1. FDS Verification Matrix

  ------------- ---------------------------------------- ----------------
  Section       Requirement                              Verification
                                                         Method

  3.1           NASA Provided Flight Dynamics Services   D

  3.2           Mission Characteristics                  D

  3.2.1         Raw Data Latency                         D

  3.3           Software, Hardware, Personnel, and       \-
                Facilities                               

  3.3.1         Software and Hardware                    I

  3.3.2         Personnel and Facilities                 I

  3.4           Mission Phases Support                   \-

  3.4.1         Maneuver Constraints                     \-

  3.4.1.1       High Latitudes                           I

  3.4.1.2       Single maneuver                          I

  3.4.1.3       Frozen Orbit Maintenance                 I

  3.4.1.4       Maneuver Frequency                       I

  3.4.2         Pre-Launch Phase                         \-

  3.4.2.1       Mission Analysis and Delta-V Budget      A

  3.4.2.2       Injection Orbit Selection                A

  3.4.2.3       Reentry Analysis                         A

  3.4.2.4       Ground Station Coverage                  A

  3.4.2.5       Launch Window                            A

  3.4.2.6       Operations Planning                      D

  3.4.3         Checkout Phase                           \-

  3.4.3.1       Separation Vector                        D

  3.4.3.2       Planning and Calibration -- Orbit        D
                Raising                                  

  3.4.3.3       Planning and Calibration -- Orbit        D
                Maintenance                              

  3.4.3.4       Planning and Calibration - Inclination   D

  3.4.3.5       Thruster Calibration -- Orbit Attainment D

  3.4.3.6       Thruster Calibration -- Orbit            D
                Maintenance                              

  3.4.3.7       Orbit Determination and Prediction       D

  3.4.3.8       On-board Attitude Verification           D

  3.4.3.9       Anomaly Resolution                       D

  3.4.3.10      Sensor Calibration                       D

  3.4.3.11      Provide IIRVs                            D

  3.4.3.12      Convert Maneuver Plan                    D

  3.4.4         Calibration and Validation Phase         \-

  3.4.4.1       Planning and Calibration                 D

  3.4.4.2       On-board Orbit and Attitude              D
                Determination                            

  3.4.4.3       Anomaly Resolution                       D

  3.4.4.4       Sensor Calibration                       D

  3.4.4.5       Generation of Planning Data              D

  3.4.4.6       Provide IIRVs                            D

  3.4.4.7       Convert Maneuver Plan                    D

  3.4.5         Maneuver Planning                        D

  3.4.5.1       Drag Make-up Maneuvers                   D

  3.4.5.2       Inclination Maneuvers                    D

  3.4.5.3       Orbit Change Maneuvers                   D

  3.4.6         Groundtrack Monitoring and Prediction    \-

  3.4.6.1       Groundtrack Monitoring                   D

  3.4.6.2       Groundtrack Prediction                   D

  3.4.6.3       Output                                   D

  3.4.7         Mission Planning Support                 \-

  3.4.7.1       Real-Time Attitude                       D

  3.4.7.2       Mission Planning                         D

  3.4.7.3       Attitude Sensor Monitoring               D

  3.4.7.4       Predict Ephemeris and Maneuver Planning  D

  3.4.7.5       Maneuver Monitoring                      D

  3.4.7.6       Acquisition Data                         D

  3.4.7.7       Post-Maneuver State                      D

  3.5           Orbit & Attitude Determination           \-

  3.5.1         Operational Orbit Determination          D

  3.5.1.1       Operational Orbit Determination Accuracy \-

  3.5.1.1.1     Along Track Position                     A

  3.5.1.1.2     Across Track Position                    A

  3.5.1.1.3     Radial Position                          A

  3.5.1.1.4     Solution Latency                         D

  3.5.1.1.5     Comparison with POD                      D

  3.5.1.2       Propagation Accuracy -- Without Maneuver \-

  3.5.1.2.1     Along Track Position                     A

  3.5.1.2.2     Across Track Position                    A

  3.5.1.2.3     Radial Position                          A

  3.5.1.2.4     Propagation Latency                      D

  3.5.1.3       Propagation Accuracy -- With Maneuver    \-

  3.5.1.3.1     Along Track Position                     A

  3.5.1.3.2     Across Track Position                    A

  3.5.1.3.3     Radial Position                          A

  3.5.1.3.4     Propagation Latency                      D

  3.5.2         Operational Attitude Support             \-

  3.5.2.1       Off-Nadir Pointing Monitoring            D

  3.5.2.2       Off-Nadir Pointing Quaternion Generation D

  3.6           Sensor Support                           D

  3.6.1         Sensor Uploadable Parameters Support     \-

  3.6.1.1       Star Tracker                             \-

  3.6.1.1.1     Proper Stellar Motion                    D

  3.6.1.1.2     Star Precession                          D

  3.6.1.2       GPS Initial Condition Vector             D

  3.6.1.3       Magnetic Field                           D

  3.6.2         Sensor Calibration Support               \-

  3.6.2.1       Star Tracker and IRU                     D

  3.6.2.2       Star Tracker FOV                         D

  3.6.2.3       IRU Scale Factors and Rate Drift         D

  3.7           Products Exchange                        \-

  3.7.1         FDS Products to the Mission Operations   \-
                Center                                   

  3.7.1.1       Orbit Solutions                          D

  3.7.1.2       Maneuver Design                          D

  3.7.1.3       Groundtrack Offset                       D

  3.7.1.4       Frozen Orbit Parameters                  D

  3.7.1.5       Initial Condition Vector                 D

  3.7.1.6       Base Time Load                           D

  3.7.1.7       Orbit and Attitude Verification          D

  3.7.2         MOC Products to the Flight Dynamics      \-
                System                                   

  3.7.2.1       Propulsion Data                          D

  3.7.2.2       All S-Band Data                          D

  3.7.2.3       Solar Array Encoder Data                 D

  3.7.3         Flight Dynamics Products to the Science  \-
                Team                                     

  3.7.3.1       Inertia and Mass Properties              D

  3.7.3.2       Maneuver Plans                           D

  3.7.3.3       OOD Solutions                            D

  3.7.3.4       Star Tracker Data                        D

  3.7.4         Data and Products Archive                \-

  3.7.4.1       Permanent Archive                        D

  3.7.4.2       Archive Accessibility                    D

  3.8           Reliability                              \-

  3.8.1         Availability                             A

  3.8.2         Single Point Failures                    I

  3.8.3         Maintenance                              D

  3.9           Security                                 \-

  3.9.1         Physical Security                        I

  3.9.2         Computer Systems                         I

  3.9.3         Databases                                I

  3.9.4         Backups                                  I

  3.10          Integration and Testing Support          D

  3.11          Documentation                            D

  3.11.1        Interface Control Document               D

  3.11.2        Specification                            D

  3.11.3        Test Plan                                D

  3.11.4        Operations Handbook                      D

  3.11.5        Operational Agreements                   D

  3.12          Reviews                                  \-

  3.12.1        PDR                                      D

  3.12.2        CDR                                      D
  ------------- ---------------------------------------- ----------------

# Delivery/Installation

TBS

# Notes

## Acronym List

ARGOS Advanced Research and Global Observation Satellite

CCAR Colorado Center for Astrodynamics Research

COTS Commercial Off-the-Shelf

CDR Critical Design Review

CDRLs Contract Deliverable Requirements List

CSTOL Colorado University Spacecraft Test and Operation Language

CSM Command Storage Memory

CTU Command and Telemetry Unit

CTV Compatibility Test Van

CU Colorado University

DSN Deep Space Network

DSU Data Storage Unit

EBnet EOS Backbone Network

EDOS EOS Data and Operations System

EOR Engineering Operations Room

EOS Earth Observing System

EPGN EOS Polar Ground Network

EPGS EOS Polar Ground System

ETE End-to-End

ERO Exact Repeat Orbit

FD Flight Dynamics

FDS Flight Dynamics System

FLTSAT Fleet Satellite

FOT Flight Operations Team

FTP File Transfer Protocol

GFDS GSFC Flight Dynamics System

GFO Geosat Follow-On

GPS Global Positioning Satellite

GPT Generic Protocol Translator

GSFC Goddard Space Flight Center

I&T Integration and Test

ICD Interface Control Document

IDL Interactive Data Language

IGS ICESat Ground System

IGSMIT ICESat Ground System Mission Implementation Team

IIRV Improved Inter-Range Vector

INTA Instituto Nacional de Aeroespacial

IOT Instrument Operations Team

IP Internet Protocol

ISDN Integrated Service Digital Network

ISEF ICESat Sustaining Engineering Facility

ISF Instrument Support Facility

ITSS Information Technology and Science Services

JPL Jet Propulsion Laboratory

L&EO Launch and Early Orbit

LOSAT-X SDIO Experiment Satellite

LASP Laboratory for Atmospheric and Space Physics

MEICD MOC External Interfaces ICD

MMC Mission Monitoring Center

MO Mission Operations

MOC Mission Operations Center

MOM Mission Operations Manager

MOR Mission Operations Review

MORD Mission Operations Requirements Document

MOWG Mission Operations Working Group

MTI Multi-Spectral Thermal Imager

NORAD North American Air Defense Command

OASIS Operations and Science Instrument Support

OASIS-CC OASIS Command and Control

OASIS-PS OASIS Planning System

PDR Preliminary Design Review

RCS Revision Control System

RF Radio Frequency

RME Relay Mirror Experiment

SAFS Standard Autonomous File Server

SCC Spacecraft Control Computer

SER System Engineering Report

SME Solar Mesosphere Explorer

SNOE Student Nitric Oxide Explorer

SODM Spacecraft Operations Description Manual

SOH State of Health

SSR Solid State Recorder

STDN Spacecraft Tracking and Data Network

STK Satellite Tool Kit

STRV Space Technology Research Vehicle

SWTB Software Test Bench

TCAD Telemetry Checking, Analysis and Display

TDRSS Tracking and Data Relay Satellite System

TOCC/SWTB Test Operations Center Console Software Test Bench

UARS Upper Atmosphere Research Satellite

UHF F/O UHF Follow-On Satellite

UT University of Texas

UVIS Ultraviolet Imaging Spectrometer

WFF Wallops Flight Facility

WOTIS Wallops Orbital Tracking Information System