S. Wu and A. Deev, "Phase Insensitive Frequency Modulation Sensor for Long Distance CO2 Monitoring,"
in Conference on Lasers and Electro-Optics/Quantum Electronics and Laser Science Conference and Photonic Applications Systems Technologies,
OSA Technical Digest Series (CD)
(Optical Society of America, 2007), paper CThII3.
We report a long distance CO2 monitoring LIDAR using phase insensitive Two-Tone Frequency Modulation (TTFM) over 1.4km. We could detect 1ppm single pass CO2 changes, and could detect CO2 leaks the open air.