Miniaturized Laser Heterodyne Radiometer

environment
Miniaturized Laser Heterodyne Radiometer (GSC-TOPS-126)
A novel and compact system for measuring greenhouse gases in the environment
Overview
NASA Goddard Space Flight Center has developed a passive monitor for measuring greenhouse gases in the atmosphere including carbon dioxide, methane and carbon monoxide. Further, trace gas concentrations can be correlated with altitude, providing further delineation of composition. This is an autonomous instrument with a uniquely small footprint and is about the size of carry-on luggage.

The Technology
This instrument uses a variation of laser heterodyne radiometer (LHR) to measure the concentration of trace gases in the atmosphere by measuring their absorption of sunlight in the infrared. Each absorption signal is mixed with laser light (the local oscillator) at a near-by frequency in a fast photoreceiver. The resulting beat signal is sensitive to changes in absorption, and located at an easier-to-process RF frequency. By separating the signal into a RF filter bank, trace gas concentrations can be found as a function of altitude.
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Benefits
  • Small size (carry-on luggage sized)
  • Can correlate trace concentrations with altitude

Applications
  • Environmental Monitoring
  • Meteorology
  • Gas Line Monitoring for methane
Technology Details

environment
GSC-TOPS-126
GSC-16327-1
8699029
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Solid State Carbon Dioxide (CO2) Sensor
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