Gaussian Beam Propagation Simulation

This MATLAB simulation framework enables comprehensive analysis of Gaussian beam propagation through atmospheric conditions. The implementation models key optical phenomena using the paraxial wave equation and incorporates atmospheric turbulence effects through phase screen generation algorithms. Researchers can modify critical parameters including beam waist size, wavelength, propagation distance, and atmospheric refractive index structure constant (Cn²) to observe their impact on beam characteristics. The simulation employs Fourier transform-based beam propagation methods to calculate field evolution, with visualization modules displaying real-time beam waist distribution profiles and intensity variations along the transmission path. Key functions include gaussianBeamInit() for initial field setup, atmosphericPhaseScreen() for turbulence modeling, and propagateField() for numerical beam propagation using angular spectrum or split-step methods. Analysis capabilities extend to quantifying beam broadening, centroid wandering, and scintillation effects through statistical processing of multiple realization runs. The modular architecture allows extension to alternative environments including underwater or free-space optical transmission scenarios, providing valuable insights into electromagnetic wave behavior across different media. Post-processing tools generate quantitative metrics for beam quality factor M², Strehl ratio, and long-term beam spread compared to theoretical diffraction-limited propagation.