Fig. 1. Intensity and phase distribution before and after propagating through the atmospheric turbulence at the distance of 1 km with different Cn2. (a) Case of LG beams. (b) Case of Bessel beams. In the map of the phase distribution, black denotes 0 and white denotes 2π.

Fig. 2. OAM spectra of single-mode LG beam and Bessel beam with topological charge of +3 before and behind turbulence. (a) Case of before propagating through turbulence. (b), (c), and (d) Cases of after propagating through turbulence at the distance of 1 km and with Cn2 of 1×10−13, 1×10−14, and 1×10−15  m−2/3, respectively.

Fig. 3. Intensity and phase distribution of multiplexed vortex beams before and after propagating through the atmospheric turbulence at the distance of 1 km with different Cn2. The multiplexed beams consist of four channels, whose topological charges are −6, −2, +3, and +7, respectively. (a) Case of multiplexed LG beams. (b) Case of multiplexed Bessel beams. In the map of the phase distribution, black denotes 0 and white denotes 2π.

Fig. 4. OAM spectra of multiplexed LG beams and Bessel beams with topological charge of −6, −2, +3, and +7 before and behind turbulence. (a) Case of before propagating through turbulence. (b), (c), and (d) Cases of after propagating a distance of 1 km through turbulence with Cn2 of 1×10−13, 1×10−14, and 1×10−15  m−2/3, respectively.

Fig. 5. (a) Curves show the relationship between the desired channel proportion of the two vortex beams and the propagating distance. (b) Desired channel proportions of LG beams with different radial index when they propagate through weak turbulence (Cn2=1×10−15  m−2/3) at the distance of 1 km.