Mutual coherence function based topological charge detection in a Gaussian vortex beam optical communication system

Abstract

We investigate a topological charge (TC) detection schema for an optical communication system employing Gaussian vortex beam (GVB). In this scenario, the transmitter maps the electrical message symbols to the TCs of GVBs. Thus obtained optical signal propagates in turbulent atmosphere arriving at the receiver, where a detection process is implemented to determine the TC of GVB by correlating the imaginary part of the mutual coherence function (MCF) of the incoming beam against the stored profiles. The feasibility of such a schema is firstly established by examining and comparing the analytical formulation of MCF and that of random phase screen setup. The latter is then used to explore the success rate and boundaries of this particular detection schema. Our results show that the proposed detection schema can operate with a error rate of 5 % at a link length of 5.5 km and atmospheric turbulence structure constant of 10-14.

Evolution properties of partially coherent electromagnetic elliptical vortex beam propagating through atmospheric turbulence

“…al have proposed that vortex beam can carry a spiral phase factor exp(in j) (n is the topological charge and j denotes the azimuthal angle) and each photon in the beam has an orbital angular momentum (OAM) of n,  where  is the reduced Planck constant. Meanwhile, vortex beam can improve the channel capacity of communication system by OAM coding or OAM multiplexing [12,13]; and can resist affects caused by turbulent atmosphere [5,[14][15][16][17][18][19][20] due to characteristics of itself. Moreover, elliptical beam also is a special beam, characterized by having elliptical intensity distribution [21][22][23][24].…”

Paraxial propagation characteristics of a controllable anomalous hollow vortex beam in free space

“…As a special kind of light field, optical vortex not only has a spiral wavefront phase structure, but also has a definite photon orbital angular momentum in the process of propagation, which provides an important theoretical basis for the application of optical vortex. Due to the uniqueness of the vortex field, the vortex beams are investigated as promising resources and have been applied in many research fields, including particle trapping [25], optical manipulation [26], high-resolution lithography [27,28], and optical communications [29][30][31][32]. As far as we know, propagation of a controllable anomalous hollow beam carrying optical vortex within uniaxial crystals has been discussed and analyzed [33].…”

Channel capacity and quantum entanglement of autofocusing hypergeometric-Gaussian beams through non-Kolmogorov turbulence

“…One of the prime interests of wireless optical communication is to find laser beams that are either nondiffracting or have well-defined orbital angular momentum (OAM) along a propagation channel. The applications of these special beams are found very promising in various fields, such as optical trapping, metrology, and wireless optical communication [1][2][3][4][5][6]. Unfortunately, OAM can be susceptible to atmospheric turbulence when distributing through the free space [7].…”