Atmospheric Sounder Spectrometer by Infrared Spectral Technology

The ASSIST II is the field deployable sounder that the atmospheric community has been waiting for. It is the first product that includes a self-calibrating spectroradiometer, a network-enabled control software that can operate from anywhere in the world and an integrated data processing pipeline that generates in near real time the end products that you need, autonomously.

  • Works out of the box: Highly integrated hardware and software (Edgar) allows you to install your instrument virtually anywhere. Turn the instrument on and it will start sounding the atmosphere and send you relevant data!
  • Trust your results: End-to-end performance validated in the field by the scientific community
  • Manipulate less data: Produces atmospheric parameter profiles directly, not only interferograms or spectra
  • See further: Highest sensing performances available, using state-of-the-art technology and software algorithms
  • Use less manpower: True unattended 24/7 operation, with tools to help you keep track of its operation.
  • Work from anywhere: 100% remotely controllable
  • Measures temperature, water vapor, O3 CO, CO2, CH4 and NOx vs altitude (Atmospheric profiles)
  • Generate temperature and moisture profile every 2 minutes (near real time)
  • High accuracy measurements for weather applications
  • High vertical resolution and high temporal resolution
  • Integrated and automatic radiometric calibration
  • Extensive instrument health monitoring
  • Network-centered architecture
  • Extensive remote monitoring for maintenance
  • Accepts additional user devices via the built-in USB, LVDS, and CameraLink interfaces
  • Rugged construction (field deployable)

Michelson interferometer :

  • Spectral range: 500 to 5,000 cm-1 (Optional extended range from 400 to 5,000 cm-1)
  • Single plate KBr beamsplitter (self compensated);
  • Nominal beam diameter at beam stop: 2.54 cm.
  • Maximum beam divergence is 45 milliradians full angle;
  • Throughput: 0.00805 sr cm2
  • Spectral sampling: 0.5 cm-1;
  • HeNe laser metrology system (for digital sampling and mirror velocity control) mounted on pre-aligned assembly for easy replacement);
  • Sampling rate (laser fringe rate: 32khz to 100 kHz, computer selectable)

Offer 3 optimized scan speeds:

  • 32KHz (1.14 scan/sec.)
  • 50KHz (1.8 scans/sec.)
  • 100KHz (3.56 scan/sec.)

Mirror speed stability:

  • 5% rms at 100KHz
  • 1% rms at <50KHz

Communication interface:
Calibration unit:
2 high emissivity blackbodies are permanently mounted on the ASSIST II. They are automatically selected according to the desired calibration sequence.


Effective Emissivity >0.9998
Temperature Range ambient to 70.00oC
Radiance uncertainty <±0.005 K
Temperature Display Resolution (as  per controller BC-231)
Temperature Stability 0.005C° over 120 sec.
Temperature Gradient <0.35C
Temperature Setting Resolution 0.001C°
Temperature knowledge ± 0.1 K° Absolute
Aperture diameter 2,75 inch
Contact us to get more details