Monday, 10 February 2003
RETRIVAL AND VALIDATION OF THE REFRACTIVE INDEX STRUCTURE FUNCTION FROM 50MHz RADAR DATA
The Air Force Research Laboratory (AFRL), Directed Energy Directorate (DE) works with the Airborne Laser (ABL) program to provide atmospheric measurements of optical turbulence. Optical turbulence is small-scale variations in the index of refraction that cause plane waves to distort as they pass through the atmosphere. The ABL program works to understand and predict optical turbulence. The ability to retrieve the refractive index structure function (CN^2) from the 50MHz radar at Vandenberg AFB, CA provides continuous optical turbulence measurements that will be used to validate optical turbulence predictions and wave optics performance. AFRL/DE and the ABL program have developed a process to calculate CN^2 from the 50MHz noise/signal-to-noise data and have run several campaigns to verify the CN^2 data against validated optical turbulence measurements. AFRL/DE and the ABL program office have integrated their CN^2 calculations with known radar processing codes and are comparing the results to check for best performance. AFRL/DE and the ABL program will present the results of the validation efforts and the performance comparison at the 12th Symposium on Observations and Instruments.