Remote sensing of air pollution incorporating integrated-path differential-absorption and coherent-Doppler lidar

An innovative complex lidar system deployed on an airborne rotorcraft platform for remote sensing of atmospheric pollution is proposed and demonstrated. The system incorporates integrated-path differential absorption lidar (DIAL) and coherent-doppler lidar (CDL) techniques using a dual tunable TEA CO2 laser in the 9–11 μm band and a 1.55 μm fiber laser. By combining the principles of differential absorption detection and pulsed coherent detection, the system enables agile and remote sensing of atmospheric pollution. Extensive static tests validate the system's real-time detection capabilities, including the measurement of concentration-path-length product (CL), front distance, and path wind speed of air pollution plumes over long distances exceeding 4 km. Flight experiments is conducted with the helicopter. Scanning of the pollutant concentration and the wind field is carried out in an approximately 1 km slant range over scanning angle ranges from 45° to 65°, with a radial resolution of 30 m and 10 s. The test results demonstrate the system's ability to spatially map atmospheric pollution plumes and predict their motion and dispersion patterns, thereby ensuring the protection of public safety.