Appendix 4.6.c a Multigrid Preconditioned Conjugate Gradient Method for Large Scale Wavefront Construction
نویسندگان
چکیده
We introduce a multigrid preconditioned conjugate gradient (MGCG) iterative scheme for computing open loop wavefront reconstructors in the adaptive optics (AO) system of large telescopes. We present numerical simulations which indicate that our MGCG method has a rapid convergence rate for a wide range of sub-aperture gradient measurement signal-to-noise ratios. The cost per iteration is order N logN , where N is the number of degrees of freedom. Hence, our scheme provides for fast wavefront simulation and control in large scale AO systems. OCIS Codes : (010.1080) Adaptive optics; (010.7350) Wavefront sensing
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تاریخ انتشار 2001