Research on application of local oscillator power locking method to laser heterodyne radiometer

Laser heterodyne radiometer has the advantages of low cost, small size, and high spectral resolution. It can expand existing ground carbon measurement network, verify satellite observation results, provide data coverage outside area. Using laser radiometer, is presented a prototype near-infrared based on erbium-doped fiber amplifier that realize local oscillator power locking. In distributed feedback semiconductor with center wavelength 1.603 μm used as light source. The to enhance power, automatic control circuit adopted lock output optical amplifier. baseline slope caused by change eliminated, whole layer atmospheric transmittance spectrum without fitting measured. instrument performance highly integrated an evaluated in detail, CO<sub>2</sub> measured Science Island (31.9°N, 117.2°E) Hefei. Six groups spectra are obtained during period one day, which compared simulation results from radiation model, showing they consistent each other. experimental show application improve optimize its structure, equipment supplement for realizing unattended long-term concentration building comprehensive network.