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This PDF file contains the front matter associated with SPIE
Proceedings Volume 7813, including the Title Page, Copyright
information, Table of Contents, and the Conference Committee listing.
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The next generation of NOAA's Geostationary Operational Environmental Satellite system, Series R (GOES-R)
provides continuity of the GOES mission and improvement of its remotely-sensed environmental data. The GOES-R
system consists of the Space and Ground Segments. The Space Segment consists of spacecraft bus, its remote-sensing
instruments, and communications payloads; while the Ground Segment consists of all Earth-based functions, provides
satellite operations and instrument product generation and distribution. This paper presents an overview of the GOES-R
Ground Segment (GS) architecture as it continues to evolve consistent with the GOES-R Ground Segment Project (GSP)
approved requirements documents. The GOES-R Ground Segment operates from three sites. The first is the NOAA
Satellite Operations Facility (NSOF) in Suitland, MD which houses the primary Mission Management (MM), and
selected Enterprise Management (EM), Product Generation (PG), and Product Distribution (PD) functions. The Wallops
Command and Data Acquisition Station (WCDAS), located in Wallops, VA, provides the primary space
communications services, EM and MM functions, and selected PG and PD functions. The third site is a geographically
diverse remote backup facility (RBU) located at Fairmont, WV. The architecture has been developed to allow integrated
operation within a geographically distributed framework. Because of the unique configuration of the Mission
Management Element, the Wallops Command and Data Acquisition Site will have the ability to assume control of
satellite operations in the event of an emergency - when authorized by the primary NSOF controllers. This concept
allows the Enterprise Management element to have available a wide range of capabilities governed by operations policy
rather than the need for system upgrades. This concept also provides flexibility for addition and deletion of modules for
major functions. The use of Service Based Architecture concepts within the Product Generation element (PG) provides
service interaction capabilities for product generation with only a fraction of the necessary overhead.
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The GOES-R Ground System (GS) will produce a much larger set of products with higher data density than previous
GOES systems. This requires considerably greater compute and memory resources to achieve the necessary latency and
availability for these products. Over time, new algorithms could be added and existing ones removed or updated, but the
GOES-R GS cannot go down during this time. To meet these GOES-R GS processing needs, the Harris Corporation will
implement a Product Generation (PG) infrastructure that is scalable, extensible, extendable, modular and reliable. The
primary parts of the PG infrastructure are the Service Based Architecture (SBA) and the Distributed Data Fabric (DDF).
The SBA is the middleware that encapsulates and manages science algorithms that generate products. The SBA is
divided into three parts, the Executive, which manages and configures the algorithm as a service, the Dispatcher, which
provides data to the algorithm, and the Strategy, which determines when the algorithm can execute with the available
data. The SBA is a distributed architecture, with services connected to each other over a compute grid and is highly
scalable. This plug-and-play architecture allows algorithms to be added, removed, or updated without affecting any
other services or software currently running and producing data. Algorithms require product data from other algorithms,
so a scalable and reliable messaging is necessary. The SBA uses the DDF to provide this data communication layer
between algorithms. The DDF provides an abstract interface over a distributed and persistent multi-layered storage
system (memory based caching above disk-based storage) and an event system that allows algorithm services to know
when data is available and to get the data that they need to begin processing when they need it. Together, the SBA and
the DDF provide a flexible, high performance architecture that can meet the needs of product processing now and as
they grow in the future.
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GOES-R, the next generation of the National Oceanic and Atmospheric Administration's (NOAA) Geostationary
Operational Environmental Satellite (GOES) System, represents a new technological era in operational geostationary
environmental satellite systems. GOES-R will provide advanced products that describe the state of the atmosphere, land,
oceans, and solar/ space environments over the western hemisphere. The Harris GOES-R Ground Segment team will
provide the software, based on government-supplied algorithms, and engineering infrastructures designed to produce and
distribute these next-generation data products. The Harris GOES-R Team has adopted an integrated applied science and
engineering approach that combines rigorous system engineering methods, with modern software design elements to
facilitate the transition of algorithms for Level 1 and 2+ products to operational software. The Harris Team GOES-R GS
algorithm framework, which includes a common data model interface, provides general design principles and
standardized methods for developing general algorithm services, interfacing to external data, generating intermediate and
L1b and L2 products and implementing common algorithm features such as metadata generation and error handling.
This work presents the suite of GOES-R products, their properties and the process by which the related requirements are
maintained during the complete design/development life-cycle. It also describes the algorithm architecture/engineering
approach that will be used to deploy these algorithms, and provides a preliminary implementation road map for the
development of the GOES-R GS software infrastructure, and a view into the integration of the framework and data
model into the final design.
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In an earlier paper [Cota et al., Proc. SPIE 7087, 1-31 (2008)] we described how The Aerospace Corporation's
Parameterized Image Chain Analysis & Simulation SOftware (PICASSO) may be used with a reflectance calibrated
input scene, in conjunction with a limited number of runs of AFRL's MODTRAN4 radiative transfer code, to quickly
predict the top-of-atmosphere (TOA) radiance received by an earth viewing sensor, for any arbitrary combination of
solar and sensor elevation angles. In the present paper, we extend the method to the short and midwave IR, where
reflected solar and emitted thermal radiation both contribute to the TOA radiance received by a downlooking sensor.
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In a companion paper presented at this conference we described how The Aerospace Corporation's Parameterized
Image Chain Analysis & Simulation SOftware (PICASSO) may be used in conjunction with a limited number of runs
of AFRL's MODTRAN4 radiative transfer code, to quickly predict the top-of-atmosphere (TOA) radiance received
in the visible through midwave IR (MWIR) by an earth viewing sensor, for any arbitrary combination of solar and
sensor elevation angles. The method is particularly useful for large-scale scene simulations where each pixel could
have a unique value of reflectance/emissivity and temperature, making the run-time required for direct prediction via
MODTRAN4 prohibitive. In order to be self-consistent, the method described requires an atmospheric model
(defined, at a minimum, as a set of vertical temperature, pressure and water vapor profiles) that is consistent with the
average scene temperature. MODTRAN4 provides only six model atmospheres, ranging from sub-arctic winter to
tropical conditions - too few to cover with sufficient temperature resolution the full range of average scene
temperatures that might be of interest. Model atmospheres consistent with intermediate temperature values can be
difficult to come by, and in any event, their use would be too cumbersome for use in trade studies involving a large
number of average scene temperatures. In this paper we describe and assess a method for predicting TOA radiance
for any arbitrary average scene temperature, starting from only a limited number of model atmospheres.
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The development and testing of thermal signature tracking algorithms burdens the developer with a method
of testing the algorithm's fidelity. Although actual video is normally used for testing tracking algorithms, to
evaluate performance in a variety of configurations, the acquisition of suitable video data volume is
prohibitive. As an alternative to actual video we are developing accurate synthetic thermal infrared models
of vehicles that will be incorporated into background infrared images generated using the Digital Image and
Remote Sensing Image Generation (DIRSIG) software package. Motion for the targets within the
background scene is generated using the open-source Simulation of Urban MObility (SUMOTM) software
package. ThermoAnalytics' Multi-Service Electro-optic Signature (MuSESTM) software package is used to
model thermal emission from the object of interest. The goal is to accurately incorporate thermal signatures
of moving targets into realistic radiometrically calibrated scenes, and to then test and evaluate tracking
algorithms using both visible and thermal infrared signatures for improved day and night detection
capability. The software packages have been integrated together for a synthetic video
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Northrop Grumman Aerospace Systems (NGAS) has a long
legacy developing and fielding hyperspectral sensors,
including airborne and space based systems covering the
visible through Long Wave Infrared (LWIR) wavelength
ranges. Most recently NGAS has developed the
Hyperspectral Airborne Terrestrial Instrument (HATI) family
of hyperspectral sensors, which are compact airborne
hyperspectral imagers designed to fly on a variety of
platforms and be integrated with other sensors in NGAS's
instrument suite. The current sensor under development is
the HATI-2500, a full range Visible Near Infrared (VNIR)
through Short Wave Infrared (SWIR) instrument covering the
0.4 - 2.5 micron wavelength range with high spectral
resolution (3nm). The system includes a framing camera
integrated with a GPS/INS to provide high-resolution
multispectral imagery and precision geolocation. Its compact
size and flexible acquisition parameters allow HATI-2500 to
be integrated on a large variety of aerial platforms. This
paper describes the HATI-2500 sensor and subsystems and its
expected performance specifications.
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The Visible/Infrared Imager Radiometer Suite (VIIRS) is the next-generation imaging spectroradiometer for the future operational polar-orbiting environmental satellite system. A successful Flight Unit 1 has been delivered and integrated onto the NPP spacecraft. The flexible VIIRS architecture can be adapted and enhanced to respond to a wide range of requirements and to incorporate new technology as it becomes available. This paper reports on recent design studies to evaluate building a MW-VLWIR dispersive hyperspectral module with active cooling into the existing VIIRS architecture. Performance of a two-grating VIIRS hyperspectral module was studied across a broad trade space defined primarily by spatial sampling, spectral range, spectral sampling interval, along-track field of view and integration time. The hyperspectral module studied here provides contiguous coverage across 3.9 - 15.5 μm with a spectral sampling interval of 10 nm or better, thereby extending VIIRS spectral range to the shortwave side of the 15.5 μm CO2 band and encompassing the 6.7 μm H2O band. Spatial sampling occurs at VIIRS I-band (~0.4 km at nadir) spatial resolution with aggregation to M-band (~0.8 km) and larger pixel sizes to improve sensitivity. Radiometric sensitivity (NEdT) at a spatial resolution of ~4 km is ~0.1 K or better for a 250 K scene across a wavelength range of 4.5 μm to 15.5 μm. The large number of high spectral and spatial resolution FOVs in this instrument improves chances for retrievals of information on the physical state and composition of the atmosphere all the way to the surface in cloudy regions relative to current systems. Spectral aggregation of spatial resolution measurements to MODIS and VIIRS multispectral bands would continue legacy measurements with better sensitivity in nearly all bands. Additional work is needed to optimize spatial sampling, spectral range and spectral sampling approaches for the hyperspectral module and to further refine this powerful imager concept.
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A Climate Data Record (CDR) consists of a body of information of some observable of the Earth's climate
that is of sufficient information content and accuracy to allow climate science to be performed with this
record now and in the distant future. We examine the generation of a hyperspectral infrared CDR for the
Atmospheric Infrared Sounder (AIRS) instrument as good example. For the information to be accurate,
extensive pre-flight and in-flight calibration and characterization is required for spatial, spectral,
polarimetric and radiometric performance. Maintaining the accuracy in orbit requires either inherent
stability, or the ability to stabilize the calibration using additional information such as an ocean buoy
network, or ground calibration sites. In addition to having excellent data quality, documentation and
archiving are also critical. Details of the instrument design and test procedures must be recorded. All data
acquired during the preflight testing must be archived in a format and medium that will be accessible by
computers several decades into the future. A Systems Engineering approach is used to define the
requirements for the AIRS hyperspectral infrared climate data record, for performance, characterization,
and documentation. Examples are given from the AIRS project activities on how the record can be created
including a comprehensive drawing database, a document archive for all pre-flight and in-flight procedures
and reports, software and data archiving, and instrument performance verification and validation for
compliance with climate science requirements.
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The Hyperspectral Imager for the Coastal Ocean (HICO) is the only spaceborne
hyperspectral sensor designed for characterization of the coastal maritime environment. It
was taken from a set of written requirements to a complete hardware package ready for
spacecraft-level testing in 16 months. It had to meet NASA's safety requirements for the
ISS. A means of directing the sensor's line of sight to off-nadir directions was essential.
Construction of HICO was made possible by extensive use of commercial off-the-shelf
(COTS) components, with minor modifications for spaceflight/vacuum conditions where
necessary. Efficient engineering combined these components into a complete system that
met all requirements.
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Physics-based exploitation of image data from Earth observing sensors requires knowledge of the accuracy, stability and
repeatability of a sensor's radiometric response within its in-flight environment. Vicarious radiometric calibration
techniques, using terrestrial targets, provide an effective approach to obtaining this knowledge by measuring system
performance under actual operational conditions. This paper introduces a new capability for performing the vicarious
radiometric calibration of high spatial resolution sensors. The SPecular Array Radiometric Calibration (SPARC) method
employs convex mirrors to create two arrays of calibration targets for deriving absolute calibration coefficients of Earth
remote sensing systems in the solar reflective spectrum. The first is an array of single mirrors used to oversample the
sensor's point spread function (PSF) providing necessary spatial quality information needed to perform the radiometric
calibration of a sensor when viewing small targets. The second is a set of panels consisting of multiple mirrors designed
to stimulate detector response with known at-sensor irradiance traceable to the exo-atmospheric solar spectral constant.
The outcome is improved radiometric performance knowledge compared to other in-flight vicarious techniques through
reduced uncertainties in target reflectance, atmospheric effects, and temporal variability. The only ground truth needed is
the measurement of atmospheric transmittance. In addition, the simplification of calibration targets and ground truth
collection in the SPARC method makes the deployment more cost effective and portable, thus creating the opportunity
to imbed spectral, spatial and radiometric targets at a study site providing references that improve a sensor's interactivity
as a phenomenological tool. A demonstration of the SPARC method is presented based on data collected with the
IKONOS satellite operated by GeoEye. A SPARC measurement of absolute calibration coefficients for the IKONOS
multispectral bands is compared to coefficients derived from the established reflectance-based vicarious calibration
method.
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High quality imaging spectroscopy data is useful for both military and civilian applications. Current state-of-the-art
imaging spectrometers typically rely on the Offner-Chrisp (OC) optical form. Making use of a spherically concentric,
axially symmetric, and telecentric design, the OC imaging spectrometer provides excellent spectral-spatial uniformity
but with many regrets: (1) no real-entrance pupil, (2) relatively slow optical speeds, (3) required convex diffraction
grating, (4) narrow field-of-view, and (5) limited scalability. Recently, the Raytheon patented Reflective Triplet (RT)
optical design form has produced extremely large format imaging spectrometers of exceptional quality. The RT optical
design provides spectral-spatial uniformity comparable to the OC form, but with a number of advantages: (1) extremely
large fields-of-view, (2) faster optical speeds, (3) a real-entrance pupil for optimal cold shielding and calibration, (4) use
of either a prism or flat diffraction grating operating in collimated space (with an option for both simultaneously in a 2-
channel device), and (5) extremely wide spectral range using common reflective optics and multiple focal plane arrays,
dispersive elements, and entrance slits. This paper presents a number of detailed designs exemplifying the differences
between the OC and RT forms.
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This paper illustrates the pros and cons of a methodology that used test bars for throughput signal
equalization. We also introduce a special test equipment (STE) plate scale for spatial
measurement, which is recommended not only for its performance, but also for simplicity of
implementation.
The line spread function (LSF) is a classical figure of merit used to derive the modulation
transfer function (MTF) of an imaging sensor. The test requires that a uniform light source be
used to project test bars into the sensor via an integrating sphere to construct LSF curve.
However, source uniformity through the test bars is not easily achieved. Test results will be
adversely affected in cases where either the integrating sphere provides less than 100 percent
uniformity in temporal brightness for the various wavelength applications, or where the test bars
have been physically warped (on a scale of microns) due to supplier producibility variation.
To effectively utilize the existing STE, Raytheon applied a test-bar throughput signal
equalization method to correct for the light source and/or test bar dimensional non-uniformity
errors during the spatial performance evaluation. The successful approach compensated for the
STE limitations without incurring expenditures for new custom-made equipment.
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Continuous-Wave lidars are constantly evolving in order to achieve the best performances with low power and low cost.
Frequency-modulated continuous-wave (FMCW) lidar is a well-known type of lidar used for solid-target detection and
ranging with high spatial resolution. The extension of this lidar technique to the probing of distributed media (aerosols,
smoke or exhaust fumes) has recently been proposed by the authors. The main drawback in measuring extended or
distributed targets with a conventional FMCW signal is the loss of information that occurs in the retrieved signal, as it
suffers a bandpass filtering in the detection process. This implies the practical impossibility of recovering the complete
information about the target spatial distribution. A shift of the sub-carrier FM modulating signal to baseband can avoid
these effects and the desired information can be satisfactorily retrieved if the emitted signal is adequately chosen to avoid
sum-frequency components distortion.
A theoretical formulation has been developed and tested by sounding a distributed medium composed of two narrow
solid targets, which is analyzed in different configurations by changing the distance among them. The medium is probed
with both the classical sub-carrier FM bandpass signal and with the baseband one previously proposed. The experimental
results are compared with the corresponding simulations in order to assess them.
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CNES (French spatial agency) will provide the AltiKa high-resolution altimeter, Doris instrument and the LRA (Laser Retro-reflector Array) for SARAL (Satellite with ARgos and Altika) in cooperation with ISRO. The paper presents the LRA, its design and its key performances. The nine corner cube reflectors have been manufactured with very stringent dihedral angle offset precision. The tests done will be described. Specific modelisation and analysis (thermal gradient), specific test (thermo-optical test) and optimizations will be described.
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Small unmanned aerial vehicle (SUAV) imagery geometrical quality is affected by the fact that cameras which
are installed in SUAV usually are not calibrated due to the platforms size and cost constrains. To this end, image
enhancements and camera calibration processes are crucial elements of the remote sensing system architectures.
In this work we present experimental research involving SUAV platform equipped with autopilot and with ability
to accommodate a payload up to 11 pounds. SUAV platform is currently fitted with a 12MP EOS camera, which
is a subject of calibration procedures. Presented preliminary results of the research demonstrate SUAV remote
sensing feasibility.
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In order to give consideration to both resolution and swath of airborne remote sensing instrument, pan-sharpening
method was used to get high resolution pan-sharpened image. This research provides a description of the optomechanical
system design and assembly of airborne imager, VCDi-660 (Vegetation and Change Detection imager).
Opto-mechanical components of VCDi-660 consist of six optical lenses, focal plane adjustment, bore sight alignment
adjustment, filter-exchanging mechanical device and circuit protected housing. An improved adjustment device for bore
sight alignment of the multiple-band camera in this Taiwanese airborne imaging sensor, VCDi-660, has been presented.
Target of this mechanical device is to provide a translational and rotational movement in the focal plane of VCDi-660.
Sensor can be aligned into the best focal position, thus the central point deviations for individual camera module can be
less than 3 pixels in both axes in image after alignment.
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Because of the flight of the remote sensing camera in the orbit, the successive images of the scenes captured by the
remote sensing camera are different at any time. So it is difficult for the camera to implement autofocus. In this paper, an
auto-focusing method in the remote sensing camera is proposed based on successive two images captured in a short time
which have an overlapped region where scenes are same. Firstly, the space camera moving in the orbit, shoots one
picture every time the camera adjusts its focus, and then we can obtain a sequence of images after several times, from
which the displacement and the overlapped regions of two adjacent images can be calculated by image registration
algorithm. We can take every two adjacent images as a group. Therefore, every image has a value of focusing accuracy
by performing a sharpness evaluation function on the overlapped region of each image. Finally, according to the transfer
characteristic of evaluation values of every two partly overlapped images, we can unify the evaluation values in a same
merit evaluation system. And then find the maximum value of image evaluation values in a same evaluation system, so
we can find the accurate focus. Simulation experiment shows that this method works pretty well in auto focusing when
relative motion between the camera and the object is existed. This method can be used in aerial camera and remote
sensing camera.
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The effect of iso-static mount (ISM) configuration of the Cassegrain telescope primary mirror under thermal stress has
been studied. The material of mirror is selected to be Zerodur, and light weight ratio of mirror is 50%. The thermal stress
can lead to the thermal deformation and degradation of system MTF. Thermal deformation distribution of the mirror has
been calculated from the Finite Element Analysis software with the input of thermal distribution. Zernike polynomial
was then used to represent the mirror deformation such that the system MTF can be predicted. It is found that MTF of
the telescope system is sensitive for ISM arm angle ranging from 50 to 68 degrees.
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Optical Fiber strain sensor using fiber Bragg grating are poised to play a major role in structural health from
military to civil engineering. Fiber Bragg Grating sensor is a practical type of fiber optic sensors. Its measurement is
encoded with the wavelength of the optical signal reflected from fiber Bragg grating. The method of measuring the
absolute optical wavelength is a critical component of the fiber optic sensing system. To reliably detect very small
changes in the environment at the sensor, the interrogation system must provide accurate and repeatable wavelength
measurements.
Energy sources are increasingly scarce in the world. Getting oil from the oil-wells has become more and more
difficult. Therefore, new technology to monitor the oil-well condition has become extremely important. The traditional
electrical sensor system is no longer useful because of the down-hole's high temperature and high pressure environment.
The optical fiber sensing system is the first choice to monitor this condition. This system will reduce the cost and
increase the productivity.
In the high pressure and high temperature environment, the traditional packed fiber grating pressure-temperature
sensor will be no longer reliability. We have to find a new fiber grating temperature-pressure sensor element and the
interrogation system. In this work we use the very narrow bandwidth birefringent fiber grating as the sensing element.
We obtain the interrogation system has 0.1 pm resolution.
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A novel approach for simultaneous measurement of strain and temperature with a single tapered fiber Bragg
grating is proposed. This method is based on the fact that the reflectivity at central wavelength of FBG reflection changes
with chirp (strain gradient). A diode laser is locked to the central wavelength of FBG reflection. Central wavelength of
the FBG shifts with temperature. Change in reflectivity & wavelength of the diode laser were used to measure strain and
temperature on the FBG respectively.
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A novel approach for simultaneous measurement of static/dynamic strain and temperature with a pair of
matched fiber Bragg grating(FBG)s is proposed. When a diode laser locked to the mid reflection frequency of reference
FBG is used to illuminate the sensor FBG, reflected intensity changes with strain on sensor FBG. Reference FBG
responds with temperature on sensor FBG and is immune to strain, hence, wavelength of the diode laser acts as a
signature for temperature measurement. Theoretical sensitivity limit for static strain and temperature are 1.2 nε √Hz and
0.0011 °C respectively. Proposed sensor shows a great potential in high sensitive strain measurements with a simplified
experimental setup.
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