Lommel-Gaussian Pulsed Beams Carrying Orbital Angular Momentum Propagation in Asymmetric Oceanic Turbulence

Abstract

By developing the complex phase perturbation for vortex pulsed beams in asymmetric oceanic turbulence and the spatiotemporal orthogonal basis for Lommel-Gaussian pulsed beam, we establish the received probability model of orbital angular momentum (OAM) modes for vortex pulsed beams propagating through asymmetric oceanic turbulence. Using this new model, we investigate the received probability and the pulse broadening of OAM modes of Lommel-Gaussian pulsed beam in asymmetric oceanic turbulence. Numerical simulation results show that Lommel-Gaussian pulsed beam causes a smaller pulse broadening when it propagates through oceanic turbulence with higher asymmetric factor, lower temperature structure constant, smaller inner scale and outer scale. In addition, Lommel-Gaussian pulsed beam with lower carrier frequency propagates through the oceanic turbulence with higher asymmetric factor, larger inner scale, smaller outer scale and smaller temperature structure constant, which obtains a higher received probability of signal OAM modes. For Lommel-Gaussian pulsed beams, the change of OAM quantum number has a week effect on the pulse broadening and the received probability.

Beam profile analysis in magnetoplasma medium

“…where the last expression represents a Gauss beam near the z-axis [6]. In the equation (20), it is seen that the solution is valid through the propagation direction z-axis except that z 0 = and b r =  [6,8]. The classical representation of Gauss beams are the solutions of approximate wave equation so the solutions are not exact.…”

“…Accordingly, various studies have been carried out to discover the ability of different novel laser beams to mitigate the turbulence effects. In this regard, understanding the profile of the Gauss beam in an anisotropic and uniaxially anisotropic media will pave the way towards a novel beam that will be utilized in both FSO communication links and space communication systems [18][19][20][21].…”

Scintillation Index for Spherical Wave Propagation in Anisotropic Weak Oceanic Turbulence with Aperture Averaging under the Effect of Inner Scale and Outer Scale

“…The results show that the fluctuation of temperature and salinity in ocean turbulence significantly impacts the scintillation index, and weak ocean turbulence with larger kinematic viscosity can obtain a smaller scintillation index. Moreover, the asymmetric oceanic turbulence will affect the pluse broadening and the received probability of the OAM modes in the Lommel-Gaussian pulsed beams [12].…”

Diffractive deep neural network based adaptive optics scheme for vortex beam in oceanic turbulence

“…The different OAM modes carried by the beam are orthogonal, which provides a new degree of freedom for the multiplexing of OAM beams, and increases transmission capacity and spectral efficiency [9]. Unfortunately, the spiral wavefront structure of OAM mode is easily distorted by oceanic turbulence (OT), which aggravates crosstalk between OAM modes and affects the communication quality of the UWOC system [10]. Therefore, adaptive optics (AO), as a technique that can reduce the distortion caused by turbulence, is applied to the UWOC system [11].…”