Electromagnetic waves propagation in hypersonic turbulence using fractal phase screen method

Abstract

The experimental fractal measurements of hypersonic turbulence are used to calculate the scaling exponent, spectral index, and power spectrum of hypersonic turbulence. The characteristics of electromagnetic wave propagation through hypersonic turbulence are studied using the fractal phase screen method based on the Weierstrass fractal function. The effects of the fractal dimension, inner scale, outer scale, variance of the refractive index fluctuation, and the wavelength of incident electromagnetic wave on the diffracted average-intensity distribution by a fractal phase screen are analyzed. Results show that the variance of the refractive index fluctuation determines the ratio of coherent to incoherent intensity. The fractal dimension, Reynolds number, and outer scale of hype- rsonic turbulence determine the incoherent field distribution. As the variance of the refractive index decreases, the coherent portion of the diffracted average intensity becomes clearer. With the increasing fractal dimension, the maximum diffracted average intensity decreases and the incoherent intensity becomes more evident.

Keywords:

• Hypersonic turbulence
• fractal phase screen
• weierstrass fractal function
• fractal dimension

Acknowledgments

The authors thank the reviewers for their helpful and constructive suggestions.

Disclosure statement

No potential conflict of interest was reported by the authors.