Inferring path average C^2_n values in the marine environment

Abstract

Current mathematical scintillation theory describing laser propagation through the atmosphere has been developed for terrestrial environments. Scintillation expressions valid in all regimes of optical turbulence for propagation in the maritime environment, based on what we believe to be a newly developed marine atmospheric spectrum, have been developed for spherical waves. Path average values of the structure parameter, C(n)(2), were inferred from optical scintillation measurements of a diverged laser beam propagating in a marine environment, using scintillation expressions based on both terrestrial and marine refractive index spectra. In the moderate-to-strong fluctuation regime, the inferred marine C(n)(2) values were about 20% smaller than inferred terrestrial C(n)(2) values, but a minimal difference was observed in the weak fluctuation regime. Measurements of angle-of-arrival fluctuations were used to infer C(n)(2) values in the moderate-to-strong fluctuation regime, resulting in values of the structure parameter that were at least an order of magnitude larger than the two scintillation-inferred C(n)(2) values.

Light propagation through anisotropic turbulence

“…Several experimental data and measurements indicate that the turbulence in the upper troposphere and stratosphere, or along nonhomogeneous path, deviates from predictions of the Kolmogorov model [2][3][4][5][6]. Other experiments showed that atmospheric turbulence in maritime environments can assume a different statistical behavior with respect to Kolmogorov [7][8][9][10][11][12][13]. In addition, anisotropy in stratospheric turbulent inhomogeneities has been experimentally investigated [14][15][16][17], and laboratory results have shown that turbulence can be anisotropic.…”

Temporal power spectra of irradiance scintillation for infrared optical waves’ propagation through marine atmospheric turbulence

“…The traditional Kolmogorov spectrum is primarily used in theoretical studies due to its simplicity but is valid only in the inertial subrange. Recently the marine atmospheric refractivity spectrum that presents a multiplicative factor able to describe the aforementioned characteristic bump was proposed and takes the form [12] …”

“…The effects of humidity over water make the optical waves' propagation more complicated [9,10], and the interaction between the humidity and temperature fluctuations in the marine atmosphere needs to be considered. Based on experimental data taken over the Salton Sea [10], recently a new analytic marine atmospheric refractivity spectrum has been developed [11,12], and it revealed a significant amplification of the characteristic bump compared with the terrestrial refractivity spectrum. The pronounced bump in the refractivity spectrum derived from the Salton Sea data is believed to generally represent the marine atmosphere [10].…”

“…The pronounced bump in the refractivity spectrum derived from the Salton Sea data is believed to generally represent the marine atmosphere [10]. Even though more experiments are necessary for its validation, this spectrum is a good candidate to describe atmospheric turbulence in a general marine environment [12]. It has been applied to investigate the optical waves' propagation through marine atmospheric turbulence [11,13,14].…”

Spiral spectrum of Airy beams propagation through moderate-to-strong turbulence of maritime atmosphere

“…Considering the effect of the inner-scale of turbulence, researchers [3] developed the irradiance fluctuation expressions of plane and spherical waves on the basis of the new maritime spectrum in weak optical turbulence. In maritime environments, Vetelino et al [4] proposed theoretical scintillation expressions under moderate-to-strong Kolmogorov turbulence. In weak non-Kolmogorov maritime atmospheric turbulence channels, scintillation and aperture averaging of Gaussian beams were investigated [5].…”