Research On Propagation Properties Of The Anomalous Vortex Beams In The Non-Kolmogorov Turbulence

Compared with the ordinary Gaussian beam,Vortex beam has many characteristics,such as the zero intensity of the center of the beam and the angular momentum of the orbit,etc.This characteristic makes vortex beams have high application value in many areas,for example,optical trapping,optical rotation,nonlinear optics,biomedicine,free space communication and so on.Because of its high intensity,coherence and directivity,the laser has the characteristics of large capacity,small volume and strong electromagnetic interference when applied to free space optical communication technology.In the military,but also has very important significance for laser atmospheric propagation,now the aerospace reconnaissance platform,needs to have higher spatial resolution,high temporal resolution,high spectral resolution.The future local wars also need laser weapons with higher ability to resist electronic jamming,communication capability,security and confidentiality.These systems are all transmitted in the atmosphere channel,and the biggest problem is atmospheric action.In order to improve the performance of the system,it is necessary to study and analyze the laser atmospheric transmission in depth.In this paper,we study the propagation properties of the anomalous vortex beams in the non-Kolmogorov turbulence.The main contents of this paper are as follows:1.The motivation and significance of the research are introduced.The research and development of optical vortex at home and abroad as well as the research and development of beam propagation in turbulent atmosphere at home and abroad are summarized and analyzed.2.This paper briefly introduces the basic theory and method of laser transmission,and summarizes several common refractive power spectrum of atmospheric turbulence model and atmospheric turbulence structure constant model,and introduces some evaluation parameters including beam quality,beam propagation factor,beam angle,Strehl ratio etc.3.Study of the transmission model of the anomalous vortex beams in the non-Kolmogorov turbulence.Firstly,the theory introduces the basic theory and application of the turbulence model,and based on the generalized Huygens-Fresnel principle,combined with the power of non-Kolmogorov turbulence spectral density,cross spectral density matrix is derived to push related.Then the application of unified theory of coherence and polarization,further study of the anomalous vortex beams through the non-Kolmogorov turbulence intensity distribution,degree of polarization characteristics and the spectral degree of coherence.The effects of different beam parameters and turbulence parameters on the intensity,degree of polarization and the spectral degree of coherence of the beam are investigated by numerical simulation.4.Study on the beam quality after the anomalous vortex beams through non-Kolmogorov turbulence.Firstly,the paper introduced the theory of beam quality,Based on the extended Huygens-Fresnel principle and the second-order moments of the Wigner distribution function,combined with the power of non-Kolmogorov turbulence spectrum,then the anomalous vortex beam propagation factor,the RMS beam width and the angular spread are deduced.Through numerical simulation,the control variables,respectively explore the beam propagation factor,RMS beam width,the angular spread in different transmission distance,changes with the index of turbulence,as well as in different beam parameters,different turbulence parameters,with the variation of the transmission distance,and analyze the changes of beam quality.