GOSAT-2 is the successor of the Greenhouse gases Observing SATellite (GOSAT, "IBUKI") launched in 2009 by Japan Aerospace Exploration Agency (JAXA). GOSAT-2 will continue and enhance space borne measurements of greenhouse gases started by GOSAT and monitor the impacts of climate change and human activities on the carbon cycle. It will also contribute to climate science and climate change related policies. The GOSAT-2 spacecraft will carry two earth observation instruments: FTS-2, the second generation of the TANSO-FTS and CAI-2, a Cloud and Aerosol Imager. Mitsubishi Electric Corporation is the prime contractor of GOSAT-2. Harris is the subcontractor of the spectrometer. ABB, who successfully designed, manufactured, and delivered the interferometer for the TANSO-FTS instrument for GOSAT, is currently delivering the modulator for the FTS-2 instrument to Mitsubishi Electric Corporation. Built on the TANSO-FTS heritage, FTS-2 is a thermal and near infrared sensor for carbon observation based on a Fourier transform spectrometer featuring larger optical throughput than TANSO-FTS. This paper presents an overview of the design of the FTS-2 interferometer as well as key qualification and performance verification activities conducted on the interferometer flight model.
The Atmospheric Chemistry Experiment (ACE) is a mission on-board the Canadian Space Agency’s (CSA) SCISAT-1. ACE is composed of a suite of instruments consisting of an infrared Fourier Transform Spectrometer (FTS) coupled with an auxiliary imager monitoring aerosols based on the extinction of solar radiation using two filtered detectors (visible and near infrared). A suntracker is also included to provide fine pointing during occultation. A second instrument, MAESTRO, is a spectrophotometer covering the near ultra-violet to the near infrared. In combination, the instrument payload covers the spectral range from 0.25 to 13.3 μm. The ACE mission came about from a need to better understand the chemical and dynamical processes that control the distribution of ozone in the upper troposphere and stratosphere, with particular emphasis on the Arctic region. Measurement of the vertical distribution of molecular species in these portions of the atmosphere permits elucidation of the key chemical and dynamical processes. The ACE-FTS measures the vertical distributions of trace gases as well as polar stratospheric clouds, aerosols, and temperature by a solar occultation technique from low earth orbit. By measuring solar radiation at high spectral resolution as it passes through different layers of the atmosphere, the absorption thus measured provides information on vertical profiles of atmospheric constituents, temperature, and pressure. Detailed and sensitive vertical distribution of trace gases help to better understand the chemical processes not only for ozone formation and destruction but also for other dynamic processes in the atmosphere. The ACE/SCISAT-1 satellite was successfully launched by NASA on August 12, 2003, and has been successfully operating since, now celebrating its 10th year on-orbit anniversary. This paper presents a summary of the heritage and development history of the ACE-FTS instrument. Design challenges and solutions are related. The actual on-orbit performance is presented, and the health status of the instrument payload is discussed. Potential future follow-on missions are finally introduced.
Fourier Transform Spectrometer (FTS), with its throughput, multiplex, and spectra resolution advantages, has become one of the most promising atmospheric remote-sensing instruments for the research on the global climax change and air quality evaluation. In this paper, the instrument concept and performances of a compact, portable, high resolution Fourier transform spectrometer, named B3M-FTS are reported. Sample atmospheric absorption spectra and corresponding retrieval results measured by the FTS are given. The success of atmospheric composition profile retrieval using the FTS measurements provides a useful way to understand the atmospheric chemistry, and validates the feasibility of atmospheric composition remote sensing using high resolution FTS.
The Canadian satellite SCISAT-1 developed for the Canadian Space Agency in the context of the ACE mission
(Atmospheric Chemistry Experiment) was launched in August 2003. The mission has been a tremendous technical and
scientific success. The main instrument of the ACE mission is a high-resolution Fourier Transform Spectrometer (FTS)
designed and built by ABB Bomem. Several new missions are currently considered as follow-on to the ACE mission to
ensure continuity of the extensive high-quality data set of the Earth's atmosphere that was started with the ACE mission,
but also possibly to bring new improvements and enhance the utilization of these data. A solar-occultation FTS based on
the optical design for ACE-FTS, has been selected for a planetary exploration mission to measure the atmospheric
composition of Mars that will launch in 2016.
An overview of these different missions will be presented. The need for technological evolutions will be examined for
each mission. Some evolutions imply only minor changes, for example, to cope with some parts obsolescence. Others
will require increasing instrument capabilities compared to those of the ACE instrument. These different technological
evolutions will be presented.
ABB Bomem is expanding its line of infrared remote sensing products with the addition of a new imaging
spectroradiometer. That hyperspectral instrument is based on the proven MR FTIR spectroradiometers.
This field instrument, called the MR-i, is a fast imaging Fourier Transform spectroradiometer. It generates spectral data
cubes in the MWIR and LWIR. It is designed to be sufficiently fast to acquire the spectral signatures of rapid events.
The design is modular. The two output ports of the instrument can be populated with different combinations of detectors
(imaging or not). For instance to measure over a broad spectral range, one output port can be equipped with a LWIR
camera while the other port is equipped with a MWIR camera. No dichroics are used to split the bands, hence enhancing
the sensitivity. Both ports can be equipped with cameras serving the same spectral range but set at different sensitivity
levels in order to increase the measurement dynamic range and avoid saturation of bright parts of the scene while
simultaneously obtaining good measurement of the faintest parts of the scene. Various telescope options are available for
the input port. This is a presentation of the current state of the development.
KEYWORDS: Sensors, Signal to noise ratio, Interferometers, Simulation of CCA and DLA aggregates, Mirrors, Electronics, Spectral resolution, Fourier transforms, Telescopes, Temperature metrology
The SciSat/ACE mission provided, and still provides, high quality and high spectral resolution measurements of the
atmosphere with a FTS sounder in sun-occultation configuration. Based on the comprehensive results and models of
SciSat/ACE it is foreseen that most of the desired information can also be retrieved from lower spectral resolution
measurements with higher signal-to-noise ratio (SNR) and appropriate data treatment. With the Canadian Space Agency
under the Space Technologies Development Program, ABB Analytical developed a small size sun-occultation sounder
compatible with a micro-satellite platform that has identical throughput, spectral bandwidth and vertical resolution as
ACE. The spectral resolution is decreased by a factor 25 (0.6 cm-1 instead of 0.024 cm-1 for ACE) whereas the SNR
performance is highly increased with an equal factor (target of 2500 instead of 100 for ACE over most of the spectral
bandwidth between 750 and 4000 cm-1).A prototype of the sun-occultation sounder was built, tested under various
thermal conditions and subjected to vibrations similar to those expected at launch. An outdoor experiment was also
conducted to test the instrument in sun-occultation conditions. The good behavior of the instrument indicates interesting
opportunities for such small footprint sounder on a low-cost micro-satellite mission and potentially good earth coverage
if several of such instruments are used in coordination. Depending on the scientific needs, it is possible to adapt the
proposed instrument to increase the vertical resolution and/or to extend the measurements on lower altitudes due to the
higher SNR performances.
A new generation of field-rated optical subtraction instruments for the standoff detection of chemicals will be presented.
It combines the latest ABB Bomem spectroradiometer technology and software with the concepts used in the design of
the original instrument designed and manufactured more than 12 years ago by ABB and Defence Research and
Development Canada - Valcartier.
This instrument is a Fourier-transform spectroradiometer with dual input beams. It is a passive, stand-off sensor that uses
one input port to interrogate a scene under investigation while the other input beam can be pointed at the background
scene. The instrument automatically measures the difference of spectral radiance between the target and the background
scenes by optical subtraction, hence achieving a real-time suppression of the background signal. The resulting
measurement is the unique spectral signature of the target measured in real time.
The system includes a software module to control the instrument and the acquisition parameters, a module for the
radiometric calibration and a module to perform the identification and quantification, in real time, of various gases.
An overview of the instrument design and initial results of tests are presented.
ABB Bomem is expanding its line of infrared remote sensing products with the addition of a new imaging
spectroradiometer. This hyperspectral instrument is based on the proven MR FTIR spectroradiometers.
This field instrument, called the MR-i, is an imaging Fourier Transform spectroradiometer. It generates spectral data
cubes in the MWIR and LWIR. It is designed to be sufficiently fast to acquire the spectral signatures of rapid events.
The design is modular. The two output ports of the instrument can be populated with different combinations of detectors
(imaging or not). For instance to measure over a broad spectral range, one output port can be equipped with a LWIR
camera while the other port is equipped with a MWIR camera. No dichroics are used to split the bands, hence enhancing
the sensitivity. Both ports can be equipped with cameras serving the same spectral range but set at different sensitivity
levels in order to increase the measurement dynamic range and avoid saturation of bright parts of the scene while
simultaneously obtaining good measurement of the faintest parts of the scene. Various telescope options are available for
the input port.
This is a presentation of the current state of the development.
KEYWORDS: Signal to noise ratio, Sensors, Mirrors, Space operations, Fourier transforms, NOx, Infrared spectroscopy, Imaging systems, Signal detection, Satellites
The Atmospheric Chemistry Experiment (ACE) is the mission on-board Canadian Space Agency's science satellite,
SCISAT-1. ACE consists of a suite of instruments in which the primary element is an infrared Fourier Transform
Spectrometer (FTS) coupled with an auxiliary 2-channel visible (525 nm) and near infrared imager (1020 nm). A
secondary instrument, a grating spectrometer named MAESTRO, provides spectrographic data from the near ultra-violet
to the near infrared, including the visible spectral range. With all instruments combined, the payload covers the spectral
range from 0.25 to 13.3 micron. A comprehensive set of simultaneous measurements of trace gases, thin clouds, aerosols
and temperature are being made by solar occultation from this satellite in low earth orbit. The ACE mission measures
and analyses the chemical and dynamical processes that control the distribution of ozone in the upper troposphere and
stratosphere. A high inclination (74°), low earth orbit (650 km) allows coverage of tropical, mid-latitude and polar
regions. The ACE/SciSat-1 spacecraft was launched by NASA on August 12th, 2003.
This paper presents the status of the ACE-FTS instrument, after nearly five years on-orbit. On-orbit SNR and some
telemetry signals are presented. The health status of the instrument is discussed.
The Atmospheric Chemistry Experiment (ACE) is the mission on-board Canadian Space Agency's science satellite,
SCISAT-1. ACE consists of a suite of instruments in which the primary element is an infrared Fourier Transform
Spectrometer (FTS) coupled with an auxiliary 2-channel visible (525 nm) and near infrared imager (1020 nm). A
secondary instrument, MAESTRO, provides spectrographic data from the near ultra-violet to the near infrared, including
the visible spectral range. In combination, the instrument payload covers the spectral range from 0.25 to 13.3 micron. A
comprehensive set of simultaneous measurements of trace gases, thin clouds, aerosols and temperature are being made
by solar occultation from this satellite in low earth orbit. The ACE mission measures and analyses the chemical and
dynamical processes that control the distribution of ozone in the upper troposphere and stratosphere. A high inclination
(740), low earth orbit (650 km) allows coverage of tropical, mid-latitude and polar regions. The ACE/SciSat-1 spacecraft
was launched by NASA on August 12th, 2003.
This paper presents the status of the ACE-FTS instrument, after four years on-orbit. On-orbit performance is presented.
The health and safety status of the instrument payload is discussed. Optimization of on-orbit performance is presented as
well as operational aspects. Aspects related to reliability of FTS are discussed as well as potential future follow-on
missions.
We present the recent development of a compact Michelson-like interferometer for an imaging Fourier Transform
Spectrometer (IFTS). The interferometer has a mass of less than 600 g and dimensions of about 60 mm x 90 mm x 100
mm. It is designed to be stiff to reduce its sensitivity to vibrations. Its maximum optical path difference is 1 cm. Despite
its small size it can support an etendue of 9.2x10-7 m2 sr. This interferometer is well suited to serve as the modulator for
a small IFTS when mass and volume are restricted such as onboard planetary probes, UAV, etc. This interferometer can
be adapted to a wide variety of infrared imaging detectors. It is a building block upon which can be designed a large
range of custom infrared imaging spectrometers.
The Atmospheric Chemistry Experiment (ACE) is the mission on-board Canadian Space Agency's science satellite, SCISAT-1. ACE consists of a suite of instruments in which the primary element is an infrared Fourier Transform Spectrometer (FTS) coupled with an auxiliary 2-channel visible (525 nm) and near infrared imager (1020 nm). A secondary instrument, MAESTRO, provides spectrographic data from the near ultra-violet to the near infrared, including the visible spectral range. In combination, the instrument payload covers the spectral range from 0.25 to 13.3 micron. A comprehensive set of simultaneous measurements of trace gases, thin clouds, aerosols and temperature are being made by solar occultation from this satellite in low earth orbit. The ACE mission measures and analyses the chemical and dynamical processes that control the distribution of ozone in the upper troposphere and stratosphere. A high inclination (74°), low earth orbit (650 km) allows coverage of tropical, mid-latitude and polar regions. The ACE/SciSat-1 spacecraft was launched by NASA on August 12th, 2003. This paper presents the status of the ACE-FTS instrument, after three years on-orbit. On-orbit performances as well as their optimization are presented. Needs for future missions similar to ACE are discussed.
The Greenhouse gases Observing SATellite (GOSAT) is designed to monitor the global distribution of carbon dioxide (CO2) from orbit. It is a joint project of Japan Aerospace Exploration Agency, the Ministry of Environment (MOE), and the National Institute for Environmental Studies (NIES). JAXA is responsible for the satellite and instrument development, MOE is involved in the instrument development, and NIES is responsible for the satellite data retrieval. It is scheduled to be launched in 2008. As existing ground monitoring stations are limited and still unevenly distributed, the satellite observation has advantages of global and frequent observations. The objective of the mission is in response to COP3 (Kyoto Protocol): Observation of Green House Gases (GHGs) including CO2 with 1% relative accuracy in sub-continental spatial resolution and to identify the GHGs source and sink from the data obtained by GOSAT in conjunction with the data from the ground instruments, with simulated models. In order to detect the CO2 variation of boundary layers, the technique to measure the column density and the retrieval algorithm to remove cloud and aerosol contamination are investigated. The simultaneous observation of methane (CH4), which is the second largest contribution molecule, is studied. A Thermal And Near infrared Sensor for carbon Observation (TANSO) based on a Fourier transform spectrometer (FTS) with high optical throughput and spectral resolution is currently under design for the GOSAT mission.
This paper presents an overview of the design of the TANSO interferometer as well as key reliability enhancement activities conducted during the design phase.
KEYWORDS: Signal to noise ratio, Imaging systems, Fourier transforms, Space operations, Mirrors, Sensors, Transmittance, Infrared radiation, Near infrared, Sun
The Atmospheric Chemistry Experiment (ACE) is the mission on-board Canadian Space Agency's science satellite, SCISAT-1. ACE consists of a suite of instruments in which the primary element is an infrared Fourier Transform Spectrometer (FTS) coupled with an auxiliary 2-channel visible (525 nm) and near infrared imager (1020 nm). A secondary instrument, MAESTRO, provides spectrographic data from the near ultra-violet to the near infrared, including the visible spectral range. In combination, the instrument payload covers the spectral range from 0.25 to 13.3 micron. A comprehensive set of simultaneous measurements of trace gases, thin clouds, aerosols and temperature are being made by solar occultation from this satellite in low earth orbit. The ACE mission measures and analyses the chemical and dynamical processes that control the distribution of ozone in the upper troposphere and stratosphere. A high inclination (740), low earth orbit (650 km) allows coverage of tropical, mid-latitude and polar regions. The ACE/SciSat-1 spacecraft was launched by NASA on August 12th, 2003. This paper presents the status of the ACE-FTS instrument after two years on-orbit. On-orbit performances are also covered. The health and safety status of the instrument payload is discussed. Optimization of on-orbit performance is presented as well as operational aspects.
KEYWORDS: Signal to noise ratio, Fourier transforms, Imaging systems, Transmittance, Sensors, Mirrors, Sun, Space operations, Visible radiation, Near infrared
The Atmospheric Chemistry Experiment (ACE) is the mission selected by the Canadian Space Agency (CSA) for its science satellite, SCISAT-1. ACE consists of a suite of instruments in which the primary element is an infrared Fourier Transform Spectrometer (FTS) coupled with an auxiliary 2-channel visible (525 nm) and near infrared imager (1020 nm). A secondary instrument, MAESTRO, provides spectrographic data from the near ultra-violet to the near infrared, including the visible spectral range. In combination the instrument payload covers the spectral range from 0.25 to 13.3 micron. A comprehensive set of simultaneous measurements of trace gases, thin clouds, aerosols and temperature are made by solar occultation from a satellite in low earth orbit. The ACE mission measures and analyses the chemical and dynamical processes that control the distribution of ozone in the upper troposphere and stratosphere. A high inclination (74 degrees), low earth orbit (650 km) allows coverage of tropical, mid-latitude and polar regions. The ACE/SciSat-1 spacecraft was launched by NASA on August 12th, 2003.
This paper presents the on-orbit performance of the ACE-FTS instrument. The commissioning activities allowed the activation of the various elements of the instrument and the optimization of several parameters such as gains, integration times, pointing offsets, etc. The performance validation was the last phase of the instrument hardware commissioning activities. The results of the performance validation are presented in terms of on-orbit instrument performance with respect to instrument requirements such as signal-to-noise ratio, transmittance accuracy, and spectral resolution. Results are also compared to ground validation tests performed during the thermal-vacuum campaigns. Performance is presented in terms of validation of instrument from an engineering perspective.
The Atmospheric Chemistry Experiment (ACE) is the mission selected by the Canadian Space Agency for its science satellite, SCISAT-1. ACE consists of a suite of instruments in which the primary element is an infrared Fourier Transform Spectrometer (FTS) coupled with an auxiliary 2-channel visible (525 nm) and near infrared imager (1020 nm). A secondary instrument, MAESTRO, provides spectrographic data from the near ultra-violet to the near infrared, including the visible spectral range. In combination the instrument payload covers the spectral range from 0.25 to 13.3 micron. A comprehensive set of simultaneous measurements of trace gases, thin clouds, aerosols and temperature will be made by solar occultation from a satellite in low earth orbit. The ACE mission will measure and analyze the chemical and dynamical processes that control the distribution of ozone in the upper troposphere and stratosphere. A high inclination (74 degrees), low earth orbit (650 km) allows coverage of tropical, mid-latitude and polar regions. The ACE/SciSat-1 spacecraft was launched by NASA on August 12th, 2003.
This paper presents the on-orbit commissioning of the ACE-FTS instrument. Various steps were required to safely and progressively activate each module and sub-system of the instrument. This paper describes each step and its relation with the health and safety of the instrument. The overall strategy and sequence of the commissioning activity is presented. Commissioning results are presented in terms of validation of instrument functionality from an engineering perspective. The characterization of the detector contamination is described as well as methods that were developed to mitigate this issue.
Fourier transform spectrometer (FTS) has fast optics, and it can realize high resolution within the range from visible light to thermal infrared radiation. FTS intrinsically has the problem that it takes long time to obtain spectrum, because it needs mechanical scanning. But we developed spaceborne FTS system which has the ability of high speed scanning and data handling. By high speed scanning, FTS makes it possible to have high altitude resolution in occultation, and imaging in nadir observation.
The Atmospheric Chemistry Experiment (ACE) is the mission selected by the Canadian Space Agency (CSA) for its next science satellite, SCISAT-1. ACE consists of a suite of instruments in which the primary element is an infrared Fourier Transform Spectrometer (FTS) coupled with an auxiliary 2-channel visible (525 nm) and near infrared imager (1020 nm). A secondary instrument, MAESTRO, provides spectrographic data from the near ultra-violet to the near infrared, including the visible spectral range. In combination the instrument payload covers the spectral range from 0.25 to 13.3 micron. A comprehensive set of simultaneous measurements of trace gases, thin clouds, aerosols and temperature will be made by solar occultation from a satellite in low earth orbit. The ACE mission will measure and analyze the chemical and dynamical processes that control the distribution of ozone in the upper troposphere and stratosphere. A high inclination (74 degrees), low earth orbit (650 km) allows coverage of tropical, mid-latitude and polar regions. This paper describes the results of the environmental qualification campaign of the ACE-FTS instrument flight model. Performance test results during thermal-vacuum (TVAC) testing are presented. Stability of the instrument at various temperatures under thermal and vacuum environment are discussed. Qualification of the ACE-FTS under vibrations at instrument and spacecraft levels are covered.
The Atmospheric Chemistry Experiment (ACE) is the mission selected by the Canadian Space Agency for its next science satellite, SCISAT-1. ACE consists of a suite of instruments in which the primary element is an infrared Fourier Transform Spectrometer (FTS) coupled with an auxiliary 2-channel visible (525 nm) and near infrared imager (1020 nm). A secondary instrument, MAESTRO, provides spectrographic data from the near ultra-violet to the near infrared, including the visible spectral range. In combination the instrument payload covers the spectral range from 0.25 to 13.3 micron. A comprehensive set of simultaneous measurements of trace gases, thin clouds, aerosols and temperature will be made by solar occultation from a satellite in low earth orbit. The ACE mission will measure and analyse the chemical and dynamical processes that control the distribution of ozone in the upper troposphere and stratosphere. A high inclination (74 degrees), low earth orbit (650 km) allows coverage of tropical, mid-latitude and polar regions. This paper presents the instrument-related activities in preparation for launch. In particular, activities related to the integration of instrument to spacecraft are presented as well as tests of the instrument on-board the SciSat-1 bus. Environmental qualification activities at spacecraft-level are described. An overview of the characterization and calibration campaign is presented. Activities for integration and verification at launch site are also covered. The latest status of the spacecraft is also presented.
The Solar Occultation FTS for Inclined-orbit Satellite (SOFIS) is a solar occultation Fourier transform spectrometer developed by the Ministry of the Environment (MOE) in Japan for the Global Change Observation Mission-A1 (GCOM-A1) satellite. GCOM-A1 will be placed in a 650 km non-sun-synchronous orbit, with an inclination angle of 69 degrees. ABB-Bomem is a sub-contractor of NTSpace (NEC-Toshiba Space) for the design and manufacturing of the FTS Engineering Model of SOFIS. SOFIS measures the vertical profile of the atmospheric constituents with 0.2 cm-1 spectral resolution for the spectral range covering 3-13 μm. The atmospheric vertical resolution of SOFIS is 1 km. The target of SOFIS measurements is a global distribution of O3, HNO3, NO2, N2O, CH4, H2O, CO2, CFC-11, CFC-12, ClONO2, aerosol extinction, atmospheric pressure and temperature. NTSpace in Japan is the prime contractor of SOFIS. The spectrometer is an adapted version of the classical Michelson interferometer using an optimized optical layout and moving retro-reflectors. A solid-state laser diode operating at 1550 nm is used as metrology source of the interferometer. Its highly folded optical design results in a high performance instrument with a compact size. SOFIS FTS implements high performance control techniques to achieve outstanding speed stability of the moving mechanism. This paper describes the test activities of the SOFIS-FTS Engineering Model (EM) and preliminary results. The performances of the FTS are presented in terms of key parameters like signal-to-noise ratio, modulation efficiency and stability. Spectra acquired are shown and test methodology and analyses are presented. Lessons learned during assembly, integration and testing are described as well as improvements planned to be implemented in the Flight Model.
The Atmospheric Chemistry Experiment (ACE) is the mission selected by the Canadian Space Agency for its next science satellite, SCISAT-1. ACE consists of a suite of instruments in which the primary element is an infrared Fourier Transform Spectrometer (FTS) coupled with an auxiliary 2-channel visible (525nm) and near infrared imager (1020nm). A secondary instrument, MAESTRO, provides spectrographic data from the near ultra-violet to the near infrared, including the visible spectral range. In combination the instrument payload covers the spectral range from 0.25 to 13.3 micron. A comprehensive set of simultaneous measurements of trace gases, thin clouds, aerosols and temperature will be made by solar occultation from a satellite in low earth orbit. The ACE mission will measure and analyse the chemical and dynamical processes that control the distribution of ozone in the upper troposphere and stratosphere. A high inclination (74 degrees), low earth orbit (650 km) allows coverage of tropical, mid-latitude and polar regions.
This paper describes the detailed design of the ACE-FTS instrument. The principal design drivers and trade-offs are covered as well as system engineering approaches to optimise the performance of the instrument. Its highly folded, compact and robust opto-mechanical design is described. The structural and thermal design challenges, which have considerably impacted the detailed design of the instrument, are presented. Lessons learned during the detailed design phase and manufacturing of the Flight Model are presented. The latest status of the flight model is also presented as well as preliminary test results.
KEYWORDS: Signal to noise ratio, Fourier transforms, Sensors, Imaging systems, Transmittance, Infrared spectroscopy, Interferometers, Modulation, Visible radiation, Process control
The Atmospheric Chemistry Experiment (ACE) is the mission selected by the Canadian Space Agency for its next science satellite, SCISAT-1. ACE consists of a suite of instruments in which the primary element is an infrared Fourier Transform Spectrometer (FTS) coupled with an auxiliary 2-channel visible (525 nm) and near infrared imager (1020 nm). A secondary instrument, MAESTRO, provides spectrographic data from the near ultra-violet to the near infra-red, including the visible spectral range. In combination the instrument payload covers the spectral range from 0.25 to 13.3 microns. A comprehensive set of simultaneous measurements of trace gases, thin clouds, aerosols and temperature will be made by solar occultation from a satellite in low earth orbit. The ACE mission will measure and analyze the chemical and dynamical processes that control the distribution of ozone in the upper troposphere and stratosphere. A high inclination (74°), low earth orbit (650 km) allows coverage of tropical, mid-latitude and polar regions. This paper describes the test activities around the ACE-FTS Flight Model (FM) and the preliminary results obtained. It also presents the expected performances of the instrument in terms of key parameters like signal-to-noise ratio and resolution.
The Atmospheric Chemistry Experiment (ACE) is the mission selected by the Canadian Space Agency for its new science satellite, SCISAT-1. Dr. Peter Bernath of the University of Waterloo is the ACE Mission Scientist, and ABB Bomem is the industrial contractor for the development of the ACE primary instrument. The principal goal of the ACE mission is to measure and to understand the chemical and dynamical processes that control the distribution of ozone in the upper troposphere and stratosphere. A comprehensive set of simultaneous measurements of trace gases, thin clouds, aerosols and temperature will be made by solar occultation from a satellite in a low earth orbit. A high inclination, low earth orbit will allow coverage of tropical, mid-latitude and polar regions. The ACE primary instrument is an infrared Fourier Transform Spectrometer (FTS) coupled with an auxiliary 2-channel visible and near infrared imager. The FTS, operating from 2.4 to 13.3 microns, will measure at high resolution (0.02 cm-1) the infrared absorption signals that contain information on different atmospheric layers to provide vertical profiles of atmospheric constituents. Its highly folded design results in a very high performance instrument with a compact size. The imager will monitor aerosols based on the extinction of solar radiation using two filtered detectors at 1.02 and 0.525 microns. The instrument also includes a suntracker, which provides the sun radiance to both the FTS and the imager during solar occultation of the earth's atmosphere. This paper will describe the recent developments on the ACE instrument. Results obtained with the engineering model will be given and the latest status of the flight model will be presented.
The Atmospheric Chemistry Experiment is the mission selected by the Canadian Space Agency for its new science satellite, SCISAT-1. Dr. Peter Bernatch of the University of Waterloo is the ACE Principal Investigator, and ABB Bomem is the prime contractor for the development of the ACE main instrument, a Fourier-Transform Spectrometer. The principal goal of the ACE mission is to measure and understand the chemical and dynamical processes that control the distribution of ozone in the upper troposphere and stratosphere. A comprehensive set of simultaneous measurements of trace gases, thin clouds, aerosols and temperature will be made by solar occultation from a satellite in a low Earth orbit.
Spectral radiometers and imaging radiometers have been used for decades to provide detailed information about the infrared properties of remote objects. Both of these senors provide complementary information. Even more information can be obtained using a fusion of these two instruments. A spectral imaging radiometer provides data absolutely registered in the spatial, spectral and temporal domain. In this paper we present SARIS, a new spectral imaging radiometer that will operate both from airborne and ground-based platform. SARIS will provide high speed, highly accurate, 16 X 16 spatial radiometric measurements with 1 cm-1 spectral resolution in the 2 to 5 micrometer spectral band. SARIS will measure up to 150 datacubes (a datacube is a complete spatial/spectral measurement) at a spectral resolution of 8 cm-1 and covering the spectral range from 3.5 to 5 micrometer. In this paper we present the mission, technical requirements and conceptual design of SARIS.
Laser range sensors measure the 3D coordinates of points on the surface of objects. Range images taken from different points of view can provide a more or less complete coverage of an object's surface. The geometric information carried by the set of range images can be integrated into a unified, non-redundant triangular mesh describing the object. This model can then be used as the input to rapid prototyping or machining systems in order to produce a replica. Direct replication proves particularly useful for complex sculptured surfaces. The paper will describe the proposed approach and relevant algorithms, and discuss tow test cases.
This paper presents a two-step technique to build a non-redundant surface model of an object using information provided by N registered range views. In the first processing step, the redundancy between views (e.g., 3-D information belonging to more than one view) is detected. Range views are considered as sets of 3-D points. The redundancy between the views is modeled by the Venn diagram of the N sets. Using the Venn diagram, the second processing step yields a non-redundant surface model of the object. A mesh of 3-D triangles defined in an object-centered reference frame describes the surface information present in the N range views. The proposed view integration technique is independent of the number of 3-D views and does not impose orthogonallity between them.
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