Spatial-Temporal Control Applied to Atmospheric Adaptive Optics

A framework for studying the statistics of optical turbulence in an airborne platform is being proposed. This framework accounts for static, determined dynamic (or flowing), and random aberrations. It is recognized that the random aberrations due to the aero-optic boundary layer turbulence are not statistically homogeneous. This is handled with a quasi-homogenous model for analysis. This data analysis leads to the statistical information required to design a minimum variance phase estimator along with a detailed description of the noise covariance. Signal, camera, and speckle noise are modeled in detail for the phase estimator. The phase estimator along with a high fidelity deformable mirror model is used to develop a dynamic pseudo openloop control law. This control law will be tested against detailed simulation data over a range of stressing parameters and compared to more traditional control schemes. BENEFIT: The ability to successfully exploit the characteristics of the optical disturbance, both free space turbulence and aero-optics boundary layer turbulence, in an adaptive optics compensation scheme will significantly reduce the burden on the hardware requirements. In particular an optimal control design will require less temporal and spatial bandwidth as well as operate in lower and noisier signals which reduce requirements on the laser power and coherence length. This translates to less expensive, smaller, and lighter sensors, processors, and lasers.