Ground test results and analysis advancements for the AFRL airborne CO2 DIAL system

摘要

Abstract: The Air Force Research Laboratory (AFRL) Active Remote Sensing Branch has developed the Laser Airborne Remote Sensing (LARS) system for chemical detection using the differential absorption lidar technique. The system is based on a high-power CO$-2$/ laser which can use either the standard $+12$/C$+16$/O$-2$/ or the $+13$/C$+16$/O$-2$/ carbon dioxide isotopes as the lasing medium, and has output energies of up to 5 J on the stronger laser transitions. The lidar system is mounted on a flight-qualified optical breadboard designed for installation into the AFRL Argus C- 135E optical testbed aircraft. The Phase I ground tests were conducted at Kirtland AFB in 1997, prior to the LARS flight tests performed in September 1997 at Kirtland AFB and the Idaho National Engineering and Environmental Laboratory. The Phase II ground tests were conducted in 1998 to determine the optimum performance of the LARS systems, after the incorporation of modifications and improvements suggested by the flight test results. This paper will present some of the chemical detection and radiometric results obtained during the Phase II ground tests. Following the presentation of the direct detection results, a summary of current work on a heterodyne DIAL system is given.!5