> **LANDSAT DATA CONTINUITY MISSION**
>
> **OPERATIONAL LAND IMAGER (OLI) ACRONYM LIST AND LEXICON**
>
> **June 6, 2005**

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![](media/image2.wmf){width="1.0416666666666666e-2in"
height="1.0416666666666666e-2in"}**LDCM PROJECT**

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**TABLE OF CONTENTS**

Page

[1.0 ACRONYM LIST 1-1](#acronym-list)

[2.0 LEXICON 2-1](#lexicon)

# ACRONYM LIST

**ABML** As-Built Materials List

**ABPL** As-Built Parts List

**ADF** Ancillary Data File

**ADML** As-Designed Materials List

**ADPL** As-Designed Parts List

**ALI** Advanced Land Imager

#### ANSI American National Standards Institute {#ansi-american-national-standards-institute .unnumbered}

#### AOS Advanced Orbiting Systems {#aos-advanced-orbiting-systems .unnumbered}

#### ASIC Application Specific Integrated Circuits {#asic-application-specific-integrated-circuits .unnumbered}

#### ASQC American Society for Quality Control {#asqc-american-society-for-quality-control .unnumbered}

#### ASTM American Society for Testing of Materials {#astm-american-society-for-testing-of-materials .unnumbered}

#### BER Bit Error Rate {#ber-bit-error-rate .unnumbered}

#### BRDF Bi-directional Reflectance Distribution Function {#brdf-bi-directional-reflectance-distribution-function .unnumbered}

**C&DH** Command and Data Handling

**CADU** Channel Access Data Unit

**CAGE** Commercial and Government Entity

**CCF** Contamination Control Plan

**CCP** Contamination Control Plan

**CCSDS** Consultative Committee on Space Data Systems

**CDR** Critical Design Review

**CDRL** Contract Data Requirements List

**CFR** Code of Federal Regulations

**CIL** Critical Items List

**CM** Configuration Management

**CN** Coherent Noise

**CNDs** Could-Not-Duplicates

**CO** Contracting Officer

**COC** Certificate of Completion

**COG** Center of Gravity

**COTR** Contracting Officer's Technical Representative

**COTS** Commercial Off-The-Shelf

**CPT** Comprehensive Performance Test

**CPU** Central Processing Unit

**CRM** Continuous Risk Management

**CTE** Calibration Test Equipment

**CVCM** Collected Volatile Condensable Mass

**DC** Direct Current

**DCN** Documentation Change Notices

**DID** Data Item Description

**DM** Data Management

**DN** Digital Number

**DOD** Department of Defense

**DOI** Department of the Interior

**DPA** Destructive Physical Analysis

**DRFP** Draft Request for Proposal

**DSAP** Data Storage and Playback

**DUNS** Data Universal Numbering System

**EC** Electronic Copy

**ECI** Earth Centered Inertial

**EDAC** Error Detection and Correction

**EDC** Earth Resources Observation Systems (EROS) Data Center

**EDU** Engineering Development Unit

**EEE** Electrical, Electronic, Electromechanical

**EIA** Electronic Industry Alliance

**ELV** Expendable Launch Vehicle

**EMC** Electromagnetic Compatibility

**EMI** Electromagnetic Interference

**EO-1** Earth Observer 1

**EOL** End of Life

**EOS** Earth Observing System

**ESD** Electrostatic Discharge

**ETM+** Enhanced Thematic Mapper Plus

**EVP** Environmental Verification Plan

**EVS** Earned Value System

**EWP** Eastern and Western Test Ranges

**FAR** Federal Acquisition Regulation

**FDC** Failure Detection and Correction

**FGDC** Federal Geographic Data Committee

**FMEA** Failure Mode and Effects Analysis

**FOR** Flight Operation Review

**FOV** Field of View

**FPA** Focal Plane Array

**FPE** Focal Plane Electronics

**FRB** Failure Review Board

**FTA** Fault Tree Analysis

**FWHM** Full Width Half Maximum

**GAO** General Accounting Office

**GDS** Ground Data Systems

**GEVS** General Environmental Verification Specification

**GFE** Government Furnished Equipment

**GFY** Government Fiscal Year

**GIA** Government Inspection Agency

**GIDEP** Government Industry Data Exchange Program

**GIID** General Instrument Interface Document

**GOP** Ground Operations Plan

**GPS** Global Positioning System

**GSD** Ground Sample(ing) Distance

**GSE** Ground Support Equipment

**GSFC** Goddard Space Flight Center

**HC** Hard Copy

**HUB** Historically Underutilized Business

**I&T** Integration and Test

**IAC** Independent Assurance Contractor

**IAS** Image Assessment System, Landsat 7

**IC** International Cooperator

**ICD** Interface Control Document

**IDF** Image Data File

**IOC** Initial Operational Capability

**IPC** Institute for Interconnecting and Packaging Electronic Circuits

**IPSR** Instrument Pre-Ship Review

**IRD** Interface Requirements Document

**IRU** Inertial Reference Unit

**ISO** International Organization for Standardization

**ITAR** International Traffic in Arms Regulations

**IV&V** Independent Verification and Validation

**KHB** Kennedy Space Center Handbook

**Lmax** Maximum Radiance

**Ltypical** Typical Radiance

**LDCM** Landsat Data Continuity Mission

**LMST** Local Mean Solar Time

**LOS** Line of Sight

**LPT** Limited Performance Test

**LRR** Launch Readiness Review

**LTAP** Long Term Acquisition Plan

**M&PCB** Materials and Processes Control Board

**M&PCP** Materials and Processes Control Program

**MAE** Materials Assurance Engineer

**MAR** Mission Assurance Requirements

**MCM** Multi-Chip Module

**MEB** Materials Engineering Branch

**MIL** Materials Identification List

**MODIS** Moderate Resolution Imaging Spectrometer

**MODTRAN** Moderate Resolution Transmittance

**MOI** Moment of Inertia

**MOR** Mission Operations Review

**MPR** Monthly Progress Review

**MPSR** Management Program Status Review

**MRB** Material Review Board

**MSFC** Marshall Space Flight Center

**MSPSP** Missile System Prelaunch Safety Data Package

**MUA** Materials Usage Agreement

**NAS** NASA Assurance Standard

**NASA** National Aeronautics and Space Administration

**NASCOM** NASA Communications Network

**NASDA** National Space Development Agency of Japan

**NDE** Non-Destructive Examination

**NDVI** Normalized Difference Vegetation Index

**NEPAG** NASA EEE Parts Assurance Group

**NHB** NASA Handbook

**NIR** Near Infrared

**NIST** National Institute of Standards and Technology

**NPD** NASA Policy Directive

**NPOESS** National Polar Operational Environmental Satellite System

**NPSL** NASA Parts Selection List

**NRCA** Nonconformance Reporting and Corrective Action

**NSPAR** Nonstandard Parts Approval Request

**NSS** NASA Safety Standard

**NTE** Not To Exceed

**NUC** Non-Uniformity Correction

**OBP** On-Board Processor

**OLI** Operational Land Imager

**OMB** Office of Management and Budget

**OSHA** Occupational Safety and Health Administration

**OSSMA** GSFC Office of Systems Safety and Mission Assurance

**PAPL** Project Approved Parts List

**PCB** Parts Control Board

**PCP** Parts Control Plan

**PDL** Product Design Lead

**PDR** Preliminary Design Review

**PER** Performance Evaluation Review; Pre-Environmental review

**PF** Polarization Factor

**PFR** Problem / Failure Report

**PI** Principal Investigator

**PIL** Parts Identification List

**PM** Program Management

**POCC** Payload Operations Control Center

**PPL** Preferred Parts List

**PR** Program Review

**PRA** Probabilistic Risk Assessment

**PSD** Power Spectral Density

**PSM** Project Safety Manager

**PSR** Program Status Review; Pre-Shipment Review

**PWB** Printed Wiring Board

**QA** Quality Assurance

**QCM** Quartz Crystal Microbalance

**QMS** Quality Management System

**RBS** Reflective Band Sensor

**RF** Radio frequency

**RFP** Request for Proposal

**ROI** Return on Investment

**SAM** Systems Assurance Manager

**SC** Spacecraft

**SCC** Stress Corrosion Cracking

**SCM** Software Configuration Management

**SCR** System Concept Review

**SDMP** Software Development and Management Plan

**SE** Systems Engineering

**SEU** Single Event Upset

**SI** Science Instrument

**SMA** Safety and Mission Assurance

**SMD** Stored Mission Data

**SNR** Signal to Noise Ratio

**SOW** Statement of Work

**SPSR** System Pre-Ship Review

**SPVP** System Performance Verification Plan

**SQA** Software Quality Assurance

**SQMS** Software Quality Management System

**SR** System Review

**SRO** Systems Review Office

**SRR** System Requirements Review

**SRT** Systems Review Team

**SSIP** System Safety Implementation Plan

**STE** System Test Equipment

**STM** Structural Thermal Model

**SW** Software

**SWIR** Short Wave Infrared

**TBC** To Be Confirmed

**TBD** To Be Determined

**TBR** To Be Reviewed

**TBS** To Be Supplied

**TDI** Time Delay Integration

**TID** Total Incidence Dose

**TIM** Technical Interface Meeting

**TIRS** Thermal Infrared Sensor

**TML** Total Mass Loss

**TQCM** Temperature Controlled Quartz Crystal Microbalance

**T/V** Thermal/Vacuum

**USG** United States Government

**USGS** United States Geological Survey

**V&V** Verification and Validation

**VNIR** Visible and Near Infrared

**VTL** Verification Tracking Log

**WBS** Work Breakdown Structure

**WGS84** World Geodetic System 1984

# LEXICON

**Ancillary Data** - Ancillary Data consist OLI instrument and
housekeeping data, calibration data and any other supplementary data
(possibly from external sources) required to generate LDCM data
products. Ancillary data typically include relevant instrument
parameters, spacecraft attitude and ephemeris, etc.

**Auxiliary Data --** Auxillary Data in the OLI context is specific LDCM
image reconstruction data provided by the NPOESS Spacecraft over the
1553bus

**Audit -** A review of the developers, contractor\'s or
subcontractor\'s documentation or hardware to verify that it complies
with project requirements.

**Azimuth** - Angle measured in the ecliptic or equatorial plane as part
of a spherical polar coordinate system (radius or altitude, azimuth and
elevation).

**Bi-directional Reflectance Distribution Function (BRDF)** - A function
that expresses reflectance from a surface into a unit projected solid
angle as a function of both the direction of illumination and the
direction of observation.

**Bright Target Recovery** - The recovery of the system from a
saturation event such as a sun glint.

**Calibration** - the process of adjusting or normalizing to a standard.
Calibration is performed to determine correction parameters (e.g. gains
and offsets) that can be applied to the data to correct for systematic
errors.

**Coherent Noise** - A spurious, periodic pattern of noise within an
image, generally of electronic origin.

**Collected Volatile Condensable Material (CVCM)** - The quantity of
outgassed matter from a test specimen that condenses on a collector
maintained at a specific constant temperature for a specified time.

**Dark Detectors** - Detectors on the focal plane of the instrument that
are masked from receiving all incoming light, but are otherwise
identical to the detectors observing the Earth reflected radiation.
Typically these will be detectors at the ends of the sensor chip arrays
(SCA\'s)

**Dead Pixels** -- See Inoperable Pixels

**Detector column** - A set of physical detectors imaging the same
spatial locations for a single band, which are treated as a single
sensing element by having their outputs combined in time-delay
integration (TDI).

**Digital Image Data -** Two-dimensional arrays of digital numbers, one
per spectral band, representing a remotely sensed surface.

**Digital Number** **(DN)** - The radiance seen by the detector at each
pixel converted to an electrical signal and then quantized to a discrete
integer value.

**Discrepancy -** Refer to Nonconformance

**Dynamic Range** - The range of radiances over which instruments and
sensors are sensitive. The upper end of the dynamic range is the
saturation radiance. The lower end is the noise floor, i.e., the
radiance corresponding to the low radiance noise level of the
instrument. These radiances may be expressed as equivalent blackbody
temperatures for thermal bands.

**Edge Response** - The response of an imaging system to an edge target
(i.e., a low/high or high/low step function), normalized so that the
mean response on the low side of the edge target is set to zero and the
mean response on the high side of the edge target is set to 100%.

**Ephemeris** **Data** - A set of data that provides the assigned places
of a celestial body (including a manmade satellite) for regular
intervals. Ephemeris data helps to characterize the conditions under
which remote sensing data are collected and may be used to correct the
sensor data prior to analysis.

**Failure Modes and Effects Analysis (FMEA) -** A procedure by which
each credible failure mode of each item from a low indenture level to
the highest is analyzed to determine the effects on the system and to
classify each potential failure mode in accordance with the severity of
its effect.

**Federal Geographic Data Committee (FGDC)** - Established by the Office
of Management and Budget for purposes of coordinating the development,
use, sharing and dissemination of geographic data.

**Field of View** -- The angular extent of the region from which a
sensor can collect data without changing location. This can be applied
to either the sensor as a whole or to individual detector elements in
which case it is referred to as the instantaneous field of view (IFOV).

**Geodetic Reference System** - A comprehensive geodetic model of the
Earth including a geodetic reference frame, a best-fit Earth
ellipsoid/spheroid model, and an Earth gravitational model. The
inclusion of all these components allows a geodetic reference system to
serve as a horizontal and vertical datum. The standard LDCM geodetic
reference system is the World Geodetic System 1984 (WGS84).

**Ghost Image** - A \"Ghost\" image is a secondary image of an object,
which appears as either an attenuated rendition of the original object
or a blurred and attenuated version of the original object. A \"Ghost\"
also has a constant displacement vector from the original image. A
significant \"Ghost\" is defined as an image artifact when its peak
signal after background level subtraction and radiometric calibration is
above 2% of the typical radiance (Ltyp) ofr that band. This restriction
is intended to prevent ghosting from significantly affecting the
radiometric errors during normal operations.

**Ground Sample Distance (GSD)** - The distance on the ground between
adjacent image sample (pixel) centers.

**Image Compression -** The process of reducing the amount of data
required to represent the information present within an image.

**Imax -** The maximum response of an instrument as a polarizer analyzer
is rotated.

**Imin -** The minimum response of an instrument as a polarizer analyzer
is rotated.

**Inoperable Detector** - A detector that does not meet the definition
of operable detector (see **Operable Detector**).

**Inoperable Pixel -** A pixel is considered dead or inoperable if
greater than 50% of its ground projected area is not imaged by operable
detectors.

**Jitter** - High frequency variations in sensor position and/or angular
orientation leading to deviations in the actual sensor line of sight
relative to the ideal line of sight over time periods up to a few
seconds. Usually induced by mechanical vibrations from external
disturbances or internal mechanisms.

**Lossless Compression --** A data compression process such that the
data, after compression and decompression, is identical numerically to
the data prior to compression

**Modulation Transfer Function Compensation (MTFC) Resampling** - The
modulation transfer function compensation resampling technique assigns a
value to each output (resampled) pixel, computed as a weighted
combination of the surrounding input pixels. The input pixel value
weights are computed based on the output pixel location relative to the
surrounding input pixels, using an interpolation function with a spatial
frequency response that has been designed to compensate for the spatial
frequency attenuation characteristics of the imaging system\'s
modulation transfer function.

**Nadir** - That point on the celestial sphere vertically below the
observer, or 180^o^ from the zenith.

**Near Infrared** - The spectral region covering 700-1000 nm.

**Non-uniformity Correction** -- Non-uniformity correction (NUC): The
process of performing a reversible on-board relative correction of gain
and offset for each pixel to reduce the entropy of a scene to improve
data compressibility and/or reduce errors in on-board aggregation or
resampling.

**Operable Detector -** A detector is considered operable, even if out
of spec, if it meets the following requirements:

a.  The detector shall be sensitive to photons within its spectral band
    and not be saturated at expected operating temperatures under dark
    conditions.

b.  The detector\'s noise shall be less than 5 times the mean noise
    level for the band on which it occurs.

c.  The detector\'s dark current shall remain within +/- 5 times the RMS
    noise over the period between dark frame references.

d.  The detector\'s dynamic range shall be greater than 25% of the
    specified dynamic range.

**Optical Axes** - The X, Y, and Z axes of the Cartesian coordinate
system that aligns its positive Z-axis with the vector of the Optical
Axis of the telescope optical system traveling from the focal plane
towards the objective mirror of the telescope. The Optical Axes form a
right-handed coordinate system with the X-axis normal to the line formed
by the detectors in each band, and its positive direction is defined to
be towards the leading spectral band (the first band that images a
ground target object). The Y-axis is constructed as the cross product of
the Z-axis and the X-axis.

**Outgassing -** The emanation of volatile materials under vacuum
conditions resulting in a mass loss and/or material condensation on
nearby surfaces.

**Pixel** -- Short for "picture element", it is the smallest discrete
piece of image data in an image and corresponds to a single spatial
sample.

**Polarization Factor (PF)** - The modulation ratio PF =
(Imax-Imin)/(Imax+Imin) associated with a polarization sensitivity
measurement.

**Polarization Sensitivity** - The sensitivity of the system to changes
in the polarization of the signal.

**Reflective Band Sensor Data** -- Reflective Band Sensor Data are the
originally measured detector or detector column output counts at the
native spatial and spectral possibly adjusted by reversible offset and
scale corrections. Offset and scale correction reversibility implies
that the relationship between the original detector counts and the
remapped data counts is one-to-one for all measured detector output
values.

**Relative Response** - Within the context of the specifications for the
LDCM Spectral Bands, the term Relative Response has the same definition
as the Relative Spectral Radiance Response Curve.

**Relative Spectral Radiance Response Curve** -- Is a normalized
(unitless) function of Spectral Radiometric Sensitivity divided by the
peak in-band Spectral Radiometric Sensitivity. The resultant data
plotted against wavelength generally appears to be a continuous smoothly
varying function or "curve". This is an instrument-level response (can
have a filter-level spectral response curve, too) that incorporates the
optical transmission of the telescope and optical bandpass filters, and
the photon detector's radiance responsivity.

**Scattered Light** - Undesired light contamination projected on a focal
plane caused primarily by uneven surface features on optical surfaces.
This optical surface roughness is usually measured by performing a BRDF
measurement for each optical surface.

**Scene --** A scene is defined as 177km crosstrack by 170km alongtrack
image of the Earth's surface which will be identified by unique by
path/row identifier with the establishment of the new LDCM WRS-3 grid
(similar to the current WRS-2 system) once the OLI is operational on
NPOESS.

**Sharpening Band** - Single spectral band that may have a finer spatial
resolution than the other bands, usually in an integer multiple, which
allows for sharpening of the multispectral bands.

**Signal-to-Noise-Ratio (SNR) -** The ratio of the level of the
information-bearing signal power to the level of the noise power. More
precisely, the signal-to-noise ratio of the mean digital number (DN) to
the standard deviation in DN. This is a temporal noise definition in
that the mean DN is the time averaged value and the standard deviation
in DN is the standard deviation in the time series.

**Spectral Band** - An interval in the electromagnetic spectrum commonly
designated by a spectral bandwidth and a center wavelength.

**Spectral Band Center Wavelength** -- A wavelength within a spectral
band, halfway between the lower and upper band edges.

**Spectral Bandwidth** - The wavelength interval between the lower and
upper band edges. The lower band edge is the lowest wavelength where the
relative spectral radiance response is 50% of the peak response. The
upper band edge is the highest wavelength where the relative spectral
radiance response is 50% of the peak response.

**Stray Light** - Light scattered onto a detector from areas outside a
specified solid angle.

**Streaking Parameter -** The streaking parameter is defined by the
following equation:

$$Si\  = \ \left| \ Li\  - \ \frac{1}{2}\ (Li - 1\  + \ Li + 1)\  \right|\frac{\ }{\ }Li$$

(Note: factor of 100 was removed per Lencioni comment -- need
confirmation that this is correct.)

where

L~i~ is the calibrated radiance value measured for a pixel at an input
radiance level;

L~i-1~ and L~i+1~ are similarly defined for the (i--1)^th^ and (i+1)^th^
pixels.

**Swath** - The strip on the Earth that the instrument observes as it
passes overhead.

**Viewing Geometry** -The viewing geometry for which the data shall be
acquired, characterized by the zenith and azimuth angles from a ground
point to the sensor at the time of observation.

**Visible** - The spectral region covering 400-700 nm.

**Wideband Data** - The downlinked data containing LDCM sensor data and
ancillary data that have been processed and formatted for efficient data
transmission. Examples of wideband data processing steps for LDCM
purposes include lossless compression, error detection and correction
coding, pseudo-noise encoding, etc. Examples of wideband data formatting
include packet and frame-level organization of the LDCM sensor and
ancillary data.

**World Geodetic System 1984 (WGS84)** - A global geodetic reference
system defined and maintained by the National Imagery and Mapping Agency
(NIMA). WGS84 is the standard geodetic reference system for LDCM. For
remote sensing applications such as LDCM, WGS84 can be considered to be
functionally equivalent to the International Terrestrial Reference
System (ITRS) and its International Terrestrial Reference Frame (ITRF)
realizations.

**Zenith** - The point in the celestial sphere that is exactly overhead.

**Zenith Angle** - The angle between the sun and the zenith for a given
position on the Earth\'s surface.  Also, the complement of the angle
between the horizon and the sun (solar elevation).