Inverse synthetic aperture ladar (ISAL) can achieve high-resolution images for long-range moving targets, while its performance is affected by atmospheric turbulence. In this paper, the dynamic evolution of atmospheric turbulence is studied by using an infinitely long phase screen (ILPS), and the atmospheric coherent time is defined to describe the variation speed of the phase fluctuation induced by atmospheric turbulence. The simulation results show that the temporal decoherence of the echo induced by turbulence causes phase fluctuation and introduces an extra random phase, which deteriorates the phase stability and makes coherent synthesis impossible. Thus, we evaluated its effects on ISAL imaging and found a method to mitigate the impact of turbulence on ISAL images. The phase compensation algorithm could correct the phase variation in different pulses instead of that within the same pulse. Therefore, the relationship between the atmospheric coherent time and pulse duration time (rather than that between the atmospheric coherent time and ISAL imaging time) ultimately determines the ISAL imaging quality. Furthermore, these adverse effects could be mitigated by increasing the atmospheric coherent time or decreasing the pulse duration time, which results in an improvement in the ISAL imaging quality.

Controlled turbulence simulators in the laboratory have been extensively employed to investigate turbulence effects on light propagation in the atmosphere, driven by some advanced optical engineering such as remote sensing, energy-delivery systems, and free-space optical communication systems. Many studies have achieved rich results on the optical turbulence intensity, scintillation index, and power spectral density characteristics of the light propagation path in the center of a turbulence simulator, but a comprehensive analysis of the optical turbulence characteristics for different spatial locations is still lacking. We simulate turbulence with air as the medium in a classical convective Rayleigh–Bénard turbulence simulator through high-resolution computational fluid dynamics methods, the three-dimensional refractive index distribution is obtained, and the optical properties are analyzed comprehensively. It is found that the hot and cold plumes and the large-scale circulation strongly influence the inhomogeneity of $C_n^2$ in the turbulence tank, making it weak in the middle and strong near the boundary. The refractive index power spectral density at different heights is centrally symmetric, with the slope gradually deviating from the −5/3 scaling power with increasing distance from the central region. Under the log-log plot, the variation of the refractive index variance with height exhibits a three-segmented feature, showing in order: a stable region, a logarithmic profile, and a power-law profile, in the region close to the boundary. These results will contribute to the construction of a suitable turbulence simulator for optical engineering applications.

Based on the extended Huygens–Fresnel principle and infinitely long phase screen, the scintillation index and the aperture averaging effect of partially coherent beams in computational ghost imaging (CGI) with a finite bucket detector through atmospheric turbulence is investigated analytically and numerically. The signal–to–noise ratio (SNR) is used to evaluate the image quality of computational ghost imaging. It is found that a strong phase modulation effect due to increasing turbulence intensity, leads to a degradation in image quality, as well as an increase in the scintillation index. In addition, the scintillation–saturation phenomenon occurs for strong turbulence. On the other hand, reducing the propagation distance, and the degree of source coherence results in a decrease in the scintillation index and an improvement of image quality. However, deteriorating the degree of beam source coherence could weaken the aperture averaging effect. Thus, the optimal beam and bucket detector aperture size require a trade–off between the scintillation index, the aperture averaging effects, and the image quality in CGI.

Orbital angular momentum (OAM) modes can increase the capacity of free-space optical communication, but turbulence-induced modal crosstalk limits their practical use. Atmospheric turbulence simulators offer controlled test environments; however, their short propagation distances make it unclear how convection-driven spatial heterogeneity and weak scintillation affect OAM spectra and adaptive-optics (AO) correction. Here, we investigate the propagation of vortex beams through Rayleigh–Benard (RB) turbulence and evaluate AO compensation under physically controlled conditions. The RB turbulence produces strong phase distortions with weak scintillation, leading to progressive OAM modal degradation without pronounced bimodal features in the power spectrum. As the vertical temperature difference increases, modal power is redistributed into an hourglass-shaped pattern associated with the large-scale circulation of RB convection, with stronger perturbations near the boundaries and weaker perturbations in the central region. We further implement a hardware-parameterized AO framework that incorporates wavefront sensing, phase reconstruction, and deformable-mirror correction. The results show that AO effectively suppresses modal crosstalk and improves recovery of the OAM power spectrum under boundary-driven turbulence. These findings clarify how convective flow structures perturb OAM modes and provide quantitative guidance for assessing turbulence-compensation strategies in OAM-based free-space optical communication.