Practical calculation of the beam scintillation index based on the rigorous asymptotic propagation theory

Mikhail Charnotskii; Gary J. Baker

doi:10.1117/12.884632

Translator Disclaimer

25 May 2011 Practical calculation of the beam scintillation index based on the rigorous asymptotic propagation theory

Mikhail Charnotskii, Gary J. Baker

Author Affiliations +

Proceedings Volume 8038, Atmospheric Propagation VIII; 803804 (2011) https://doi.org/10.1117/12.884632
Event: SPIE Defense, Security, and Sensing, 2011, Orlando, Florida, United States

Abstract

Asymptotic theory of the finite beam scintillations (Charnotskii, WRM, 1994, JOSA A, 2010) provides an exhaustive description of the dependence of the beam scintillation index on the propagation conditions, beam size and focusing. However the complexity of the asymptotic configuration makes it difficult to apply these results for the practical calculations of the scintillation index (SI). We propose an estimation technique and demonstrate some examples of the calculations of the scintillation index dependence on the propagation path length, initial beam size, wavelength and turbulence strength for the beam geometries and propagation scenarios that are typical for applications. We suggest simple analytic bridging approximations that connect the specific asymptotes with the accuracy sufficient for the engineering estimates. Proposed technique covers propagation of the wide, narrow, collimated and focused beams under the weak and strong scintillation conditions. Direct numeric simulation of the beam waves propagation through turbulence expediently complements the asymptotic theory being most efficient when the governing scales difference is not very large. We performed numerical simulations of the beam wave propagation through turbulence for conditions that partially overlap with the major parameter space domains of the asymptotic theory. The results of the numeric simulation are used to confirm the asymptotic theory and estimate the accuracy of the bridging approximations.

Citation Download Citation

Mikhail Charnotskii and Gary J. Baker "Practical calculation of the beam scintillation index based on the rigorous asymptotic propagation theory", Proc. SPIE 8038, Atmospheric Propagation VIII, 803804 (25 May 2011); https://doi.org/10.1117/12.884632

ACCESS THE FULL ARTICLE