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Research-Acquire also includes a basic display system and a set
of post-processing functions to perform radiometric calibration,
conversion to temperature units, integration over programmable
bands, computation of theoretical Planck functions, addition, sub-
traction, multiplication, and ratios.
American SensoRx SpectRx software is used to view, process, and
organize data. It allows easy data and graphics exchange with other
Windows’ applications such as spreadsheet and word processors.
Data processing capabilities are fast and accurate. It includes a built-
in programming language, Array Basic, so that advanced users can
modify existing algorithms or create new ones for the individual
requirements of specific experiments.

10.5.2 Data Flow Outlines
Data acquisition involves notions of size, type, and transfer rate.
These are functions of scanning speed, spectral resolution, and spec-
tral range. Temporal and spectral data represent the two types
involved in an FT spectroradiometer and are linked by the Fourier
transform.
The following points will help the user understand how data is
generated and help plan an experiment by taking data flow into
account.
• The scan length is a function of resolution.
• All wavelengths are acquired simultaneously whatever the
scan length is.
• SpectRx systems acquire double-sided interferograms.
• The sampling rate is a function of the scanning speed and of
the number of samples per fringe or over-sampling factor.
• The maximum observable spectral range is determined by
the oversampling factor. In the SpectRx, the over-sampling
factor can be 1 (no over-sampling) or 2, which provides for
spectral ranges of 0 to 7899 cm and 15798 cm , respectively.
–1
–1
• Each data point is stored as a 16-bit number. Coadding or
signal averaging is done with 32-bit numbers.
• The maximum number of interferograms, which can be
recorded in kinetic mode, depends on the size of the DRAM
buffer. This is 4 MB (expandable to 64 MB) in the case of the
SpectRx 100, and 64 MB with the SpectRx 200.
• The required scanning speed is dictated by how fast an event
is to be resolved. It is limited by the ADC speed, the detector
response time, and the throughput of the electronics, including
the communication links. It is 1 cm/s in the SpectRx 100 and
25 cm/s in the SpectRx 200.