Assessment of Optical Turbulence Profiles Derived from Probabilistic Climatology

Abstract

This research effort assesses the performance of the High Energy Laser End-to-End Operational Simulation (HELEEOS) Climatological C2n optical turbulence model. Path-integrated C2n values of two HELEEOS optical turbulence pro les at 3 distinct operational altitudes are compared to values determined from measured thermosonde data. HELEEOS desert and mid-latitude sites are selected from the Extreme and Percentile Environmental Reference Tables (ExPERT) database for comparison to the thermosonde data. Statistical equivalence of the two datasets is determined through a Design of Experiments (DOE) factorial test to within 80% confidence. The HELEEOS profiles are shown to be equivalent to the thermosonde data for a 500 m boundary layer profile. Deterministic values of the 80% confidence intervals are established. The HELEEOS optical turbulence model is used as the input turbulence model for wave optics simulations. Long-term spot size measurements show that HELEEOS outperforms empirical turbulence models by as much as 17%. Recommendations are made to improve the HELEEOS graphical outputs and reference tables.