Download a free Betaspec 2 Demo version and user manual.
Betaspec Version 2: Bug fixes and modifications list.
- Betaspec Version 2.1 (Released October 28, 2009)
- Betaspec Version 2.0 (Released September 10, 2009)
The Betaspec program has been created in order to provide a user friendly interface
for generating atmospheric attenuation (α, km-1) and backscatter (β, sr-1 · m-1)
coefficients due to the presence of aerosols and molecular Rayleigh scatter by means
of running the AFGL / Sparta BACKSCAT 4.0 program over a range of wavelengths in
the 0.2 - 40 micron spectral range.
Betaspec 2.0 is a user friendly Microsoft Windows based interface program written in Visual C++.NET
which runs the US Air Force BACKSCAT (Version 4.0) program written in FORTRAN. BACKSCAT Version 4.0 uses the LOWTRAN
7/FASCODE aerosol models. The BACKSCAT program is a Lidar simulation program that
determines the lidar S/N ratio for a wide range of targets and systems. As part of this simulation,
the BACKSCAT program calculates the appropriate aerosol and Rayleigh attenuation and
backscatter coefficients for a wide range of atmospheric conditions including the US Standard
Atmosphere, clouds, haze, fog, rain, etc. |
The Betaspec 2.0 program uses the main aerosol attenuation/backscatter kernel of the
BACKSCAT program, but adds a user friendly interface to allow the user to easily change the
weather conditions and wavelength range of the calculations. The output from the BETASPEC
program is a data array of the backscatter and aerosol attenuation coefficients as a
function of wavelength and of altitude. The output file (*.BASC or *.ASC file extensions),
contains the attenuation and backscatter coefficients due to aerosols (clouds, dust, etc.) in the
It should be noted that the Betaspec program calculates the attenuation only due to aerosols and
Rayleigh scatter in the atmosphere. Such values are valid for non-resonant transmission through
the atmosphere when the optical or laser wavelength is not on a resonant absorption line of
molecules in the atmosphere. The HITRAN-PC program calculates the additional attenuation
due to resonant absorption of molecular lines in the atmosphere, which can then be added to the
attenuation due to aerosols and Rayleigh scatter for the total attenuation.
Calculations of aerosol attenuation are also embedded within the Hitran-PC 4.0
program and are used within the Hitran-PC 4.0 program when "Aerosols" are selected by the user.