Louis Moreau

ACE-FTS instrument: after five years on-orbit

The Atmospheric Chemistry Experiment (ACE) is the mission on-board Canadian Space Agencys 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.

A novel multipixel imaging differential standoff chemical detection sensor

ABB Bomem is expanding its line of infrared remote sensing products with the addition of a new multipixel imaging spectroradiometer. This hyperspectral instrument is based on the proven MR spectroradiometers. The instrument is modular and support several configurations. One of its configurations is optimised for differential acquisition in the VLWIR (cut-off near 14 μm) to support research related to the stand-off detection and quantification of chemicals. In that configuration, the instrument is equipped with a dualinput telescope to perform optical background subtraction. The resulting signal is the differential between the spectral radiance entering each input port.

A new imaging FTIR spectroradiometer

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.

Passive remote monitoring of chemical vapors with a Fourier transform infrared spectrometer

The quantization capabilities of a new passive FTIR method for the remote monitoring of chemical vapors are explored. The method is based on the use of a double beam interferometer-spectrometer optimized for optical subtraction.. The instrument is described with a particular emphasis on its capabilities for differential detection and background suppression. The algorithm developed for on-line detection and quantization of chemical vapor plume is also reviewed. The method has been successftilly used to map the integrated concentration and the temperature ofa plume ofmethanol vapor.© (2000) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.

A broadband field portable reflectometer to characterize soils and chemical samples

The developments of optical methods to characterize soils and various surface contaminants require complete and reliable databases of spectral signatures of various objects, including chemical and representative background surfaces. Ideally, the databases should be acquired in the field to properly consider the chemical mixing and heterogeneity of the surfaces. Spectral characterization instruments are common in the visible and the shortwave infrared but there are few solutions in the midwave and thermal infrared regions. ABB recently developed a broad band reflectometer based on a small FTIR spectrometer. It is capable of measuring diffuse spectral reflectance from various surfaces in the infrared from 0.7 to 13.5 microns. This sensor has been developed to be operated in the field by one person. It is lightweight (about 12 kg); it is battery powered and ruggedized for operation in harsh environments. Its operation does not require sophisticated training; it has been designed to be operated by a non-specialist. The sensor can be used to generate spectral libraries or to perform material identification if a spectral library already exists. Examples of measurements in the field will be presented.

Technological evolutions on the FTS instrument for follow-on missions to SCISAT Atmospheric Chemistry Experiment

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 Earths 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.

MRi dual-band MWIR imaging FTS

MR-i is an imaging version of the ABB Bomem MR Fourier-Transform spectroradiometer. This field instrument generates spectral datacubes 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. Overview of the instrument capabilities will be presented. Test results and results from field trials for a configuration with two MWIR cameras will be presented. That specific system is dedicated to the characterization of airborne targets. The two MWIR cameras are used to expand the dynamic range of the instrument and simultaneously measure the spectral signature of the cold background and of the warmest elements of the scene (flares, jet engines exhausts, etc.).

Review of imaging spectrometers at ABB Bomem

This presentation is an overview of the past and current imaging spectrometers projects at ABB Bomem. Recent spectral imager hardware projects will be presented in more details.

Pre-Shipment Characterization of SITELLE, a Wide-field Imaging Fourier Transform Spectrometer for the Canada-France-Hawaii Telescope

SITELLE is a wide-field imaging FTS to be deployed at the Canada-France-Hawaii Telescope. It is a challenging instrument with a unique combination of characteristics. We present the instrument and a summary of the pre-shipment tests.

The GOSAT / TANSO interferometer after five years on orbit

GOSAT (Greenhouse Gases Observing Satellite) is a Japanese Earth observation satellite dedicated to the monitoring of total column amount of carbon dioxide and methane over different locations on the planet. The main instrument of GOSAT is the TANSO Fourier Transform Spectrometer (TANSO FTS). NEC-Toshiba Space Systems was the prime integrator of the TANSO FTS. ABB provided the interferometer and its control electronics. The satellite was launched in January 2009. The mission, planned for five years, has exceeded its design life-time. This paper presents an overview of the interferometer and of its development. Special emphasis is accorded to the life time qualification activities. Analysis of the health of the interferometer on-orbit is also presented.