A device and method for generating turbulence-resistant chaotic Bessel-Gaussian beams

Abstract

This invention belongs to the field of optical communication security technology and aims to address the problem of chaotic lasers' poor robustness in turbulent environments, which severely limits their use in long-distance free-space optical communications. A device and method for generating a turbulence-resistant chaotic Bessel-Gaussian beam are provided, comprising the following steps: laser light is collimated by a first plano-convex lens, then passes through an adjustable continuous light attenuation mirror and a dielectric film reflector, and then returns to the laser. Based on the perturbation of the light field, a chaotic Gaussian beam is generated; the chaotic Gaussian beam is emitted by a first non-polarizing beam splitter, and its polarization state is adjusted by a half-wave plate and a linear polarizer to align with the operating direction of a reflective pure phase spatial light modulator. The beam is then expanded by second and third plano-convex lenses and propagated to a reflective pure phase spatial light modulator to produce a first-order chaotic Bessel-Gaussian beam. By combining chaotic lasers with Bessel beams, this invention addresses complex spatial optical communication environments.

Description

Technical Field

[0001] The present invention belongs to the field of optical communication security technology, and in particular relates to a device and method for generating a turbulence-resistant chaotic Bessel-Gaussian beam. Background Art

[0002] In recent years, with the increasing demand for optical communications, traditional cryptography faces increasing security threats, making the physical layer security of space optical communications extremely important. Chaotic lasers, due to their high bandwidth, noise-like properties, and synchronization capabilities, have become key to addressing the security challenges of modern optical communications.

[0003] The noise-like properties of chaotic lasers make transmitted information difficult to intercept and decode, thus ensuring the security of communication systems. However, chaotic lasers have poor robustness in turbulent environments, severely limiting their application in long-distance free-space optical communications. Summary of the Invention

[0004] In order to solve at least one of the above-mentioned technical problems existing in the prior art, the present invention provides a device and method for generating a turbulence-resistant chaotic Bessel-Gaussian beam.

[0005] The present invention is implemented by the following technical solution: a device for generating a turbulence-resistant chaotic Bessel-Gaussian beam, comprising a chaotic laser generation module, a chaotic Bessel-Gaussian beam construction module, and a chaotic Bessel-Gaussian beam self-healing and turbulence-resistant characteristic verification module;

[0006] The chaotic laser generation module includes a laser and a first plano-convex lens, a first non-polarizing beam splitter, an adjustable continuous light attenuation mirror, and a dielectric film reflector, which are sequentially arranged along the laser emission path of the laser. The chaotic laser generation module is used to generate a chaotic Gaussian beam.

[0007] The chaotic Bessel-Gaussian beam construction module is located on the path of the chaotic Gaussian beam emitted by the non-polarizing beam splitter, and includes a half-wave plate, a linear polarizer, a second plano-convex lens, a third plano-convex lens, and a reflective pure phase spatial light modulator arranged in sequence. The chaotic Bessel-Gaussian beam construction module is used to generate a first-order chaotic Bessel-Gaussian beam.

[0008] The chaotic Bessel-Gaussian beam self-healing and anti-turbulence characteristics verification module is located on the path of the l-order chaotic Bessel-Gaussian beam emitted by the reflective pure phase spatial light modulator, and includes an obstacle, a turbulent phase screen and a second non-polarizing beam splitter arranged in sequence. The second non-polarizing beam splitter is used to split the l-order chaotic Bessel-Gaussian beam passing through the obstacle and the turbulent phase screen. One of the l-order chaotic Bessel-Gaussian beams is coupled to a photodetector through a fifth plano-convex lens, and the output end of the photodetector is connected to an oscilloscope. The other l-order chaotic Bessel-Gaussian beam is coupled to a charge-coupled device through a 4f observation system composed of a fourth plano-convex lens and a sixth plano-convex lens.

[0009] Preferably, in the chaotic laser generation module, the laser is a Fabry-Perot single-mode semiconductor laser with a central wavelength of 850 nm, the focal length of the first plano-convex lens is 5 mm, and the first non-polarizing beam splitter is a 50:50 non-polarizing beam splitter.

[0010] Preferably, in the construction module of the chaotic Bessel-Gaussian beam, the focal length of the second plano-convex lens is 25 mm, and the focal length of the third plano-convex lens is 75 mm.

[0011] Preferably, the second non-polarizing beam splitter is a 50:50 non-polarizing beam splitter, the focal length of the fourth plano-convex lens is 25 mm, the focal length of the fifth plano-convex lens is 5 mm, and the focal length of the sixth plano-convex lens is 25 mm.

[0012] The present invention also provides a method for generating a turbulence-resistant chaotic Bessel-Gaussian beam, comprising the following steps:

[0013] The laser generates laser light, which is collimated by the first plano-convex lens, and then passes through the adjustable continuous light attenuation mirror and the dielectric film reflector. The laser light then returns to the interior of the laser and generates a chaotic Gaussian beam based on the disturbance of the light field.

[0014] A chaotic Gaussian beam is emitted from the first non-polarizing beam splitter, and its polarization state is adjusted by a half-wave plate and a linear polarizer to align with the working direction of a reflective pure phase spatial light modulator. The beam is then expanded by a second and third plano-convex lens and propagated to a reflective pure phase spatial light modulator to obtain a first-order chaotic Bessel-Gaussian beam. The reflective pure phase spatial light modulator is loaded with a holographic phase pattern consisting of a spiral phase superimposed on a radially distributed cone phase.

[0015] A l-order chaotic Bessel-Gaussian beam passes through an obstacle and a turbulent phase screen, and is split 50:50 by a second non-polarizing beam splitter. One of the l-order chaotic Bessel-Gaussian beams is coupled to a photodetector by a fifth plano-convex lens, and an oscilloscope is used to monitor whether the laser is operating in a chaotic state. The other l-order chaotic Bessel-Gaussian beam is coupled to a charge-coupled device via a 4f observation system composed of a fourth plano-convex lens and a sixth plano-convex lens, and the lateral intensity distribution of the chaotic Bessel-Gaussian beam is observed.

[0016] Preferably, after the first-order chaotic Bessel-Gaussian beam is generated, the method further includes simulating and experimentally verifying its self-healing characteristics;

[0017] The self-healing simulation process involves extracting the intensity and phase information of a chaotic laser at a specific point in time to construct a chaotic Bessel-Gaussian beam field. A blazed grating is used to simulate an opaque circular obstacle blocking the light field at the source. The angular spectrum method is used to perform Fresnel diffraction propagation, and the self-healing properties along the propagation path are observed.

[0018] The experimental verification process is as follows: use an opaque obstacle to block the chaotic Bessel-Gaussian beam on the propagation path and observe its self-healing properties.

[0019] Preferably, after the generation of the l-order chaotic Bessel-Gaussian beam, the robustness verification of the chaotic Bessel-Gaussian beam in a turbulent environment is also included:

[0020] The modified Von Karman spectrum model is used as the power spectrum density model of the turbulent phase screen, and multiple turbulent phase screens are placed on the propagation path to simulate the light field distortion and drift caused by the real environment. The actual model is given by the following formula:

[0021]

[0022] where f m =5.92 / l0 and f0=2π / L0, l0 and L0 are the inner and outer scales respectively, f is the angular spatial frequency, is the refractive index structure parameter used to measure the local turbulence intensity.

[0023] Compared with the prior art, the present invention has the following beneficial effects:

[0024] This invention proposes a turbulence-resistant chaotic Bessel-Gaussian beam. By combining a chaotic laser with a Bessel beam, it can cope with complex spatial optical communication environments. Experimental and simulation results show that even in the presence of obstacles or turbulent environments in the propagation path, the chaotic Bessel-Gaussian beam can maintain good wavefront and light intensity distribution characteristics, significantly enhancing the system's anti-interference capability and long-distance communication stability. This invention demonstrates the key role of constructing chaotic Bessel-Gaussian beams in improving free-space optical secure communications and provides a new solution for secure communications in complex environments. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0026] Figure 1 This is a system block diagram of the generation of the turbulence-resistant and self-healing chaotic Bessel-Gaussian beam and its propagation characteristics.

[0027] Figure 2 is the timing diagram of chaotic Bessel-Gaussian beams carrying orbital angular momentum of different orders;

[0028] Figure 3 is the spectrum of chaotic Bessel-Gaussian beams carrying different orders of orbital angular momentum;

[0029] Figure 4 is the intensity distribution of chaotic Bessel-Gaussian beams carrying different orders of orbital angular momentum (experimental);

[0030] Figure 5 is the intensity distribution diagram of chaotic Bessel-Gaussian beams carrying different orders of orbital angular momentum (simulation);

[0031] Figure 6 is the phase distribution diagram of chaotic Bessel-Gaussian beams carrying different orders of orbital angular momentum;

[0032] Figure 7 This is the self-healing light field diagram of the simulated chaotic Bessel-Gaussian beam when it passes through an obstacle on the propagation path;

[0033] Figure 8 This is the self-healing light field diagram of the chaotic Bessel-Gaussian beam when there is a real obstacle on the propagation path in the experiment;

[0034] Figure 9 is the normalized power attenuation diagram of the chaotic Bessel-Gaussian beam and the chaotic Gaussian beam after passing through the turbulent phase screen;

[0035] Figure 10 It is the light field distribution diagram of chaotic Bessel-Gaussian beam and chaotic Gaussian beam at different propagation distances.

[0036] In the figure: 101-laser; 102-first plano-convex lens; 103-first non-polarizing beam splitter; 104-adjustable continuous light attenuation mirror; 105-dielectric film reflector; 201-half-wave plate; 202-linear polarizer; 203-second plano-convex lens; 204-third plano-convex lens; 205-reflective pure phase spatial light modulator; 301-obstacle; 302-turbulent phase screen; 303-second non-polarizing beam splitter; 304-fourth plano-convex lens; 305-fifth plano-convex lens; 306-photodetector; 307-oscilloscope; 308-sixth plano-convex lens; 309-charge coupled device. DETAILED DESCRIPTION

[0037] The technical solutions in the embodiments of the present invention are clearly and completely described in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of them. All other implementations derived by ordinary technicians in this field based on the embodiments of the present invention without making any creative efforts are within the scope of protection of the present invention.

[0038] It should be noted that the structures, proportions, sizes, etc. illustrated in the drawings of this specification are only used to match the contents disclosed in the specification for people familiar with this technology to understand and read, and are not used to limit the conditions under which the present invention can be implemented. Therefore, they have no substantive technical significance. Any structural modification, change in proportional relationship or adjustment of size should fall within the scope of the technical content disclosed in the present invention without affecting the efficacy and purpose that can be achieved by the present invention. It should be noted that in this specification, relational terms such as first and second are only used to distinguish one entity from several other entities, and do not necessarily require or imply any actual relationship or order between these entities.

[0039] The present invention provides an embodiment:

[0040] like Figure 1As shown, a device for generating a turbulence-resistant chaotic Bessel-Gaussian beam includes a chaotic laser generation module, a chaotic Bessel-Gaussian beam construction module, and a chaotic Bessel-Gaussian beam self-healing and anti-turbulence characteristic verification module; the chaotic laser generation module includes a laser 101 and a first plano-convex lens 102, a first non-polarizing beam splitter 103, an adjustable continuous light attenuation mirror 104, and a dielectric film reflector 105, which are sequentially arranged along the laser emission path of the laser 101; the chaotic laser generation module is used to generate a chaotic Gaussian beam; the chaotic Bessel-Gaussian beam construction module is located on the path of the chaotic Gaussian beam emitted by the non-polarizing beam splitter 103, and includes a half-wave plate 201, a linear polarizer 202, a second plano-convex lens 203, a third plano-convex lens 204, and a reflective pure phase spatial light modulator 205, which are sequentially arranged; the chaotic Bessel-Gaussian beam construction module is used to generate a first-order chaotic Bessel-Gaussian beam;

[0041] The chaotic Bessel-Gaussian beam self-healing and anti-turbulence characteristic verification module is located on the path of the l-order chaotic Bessel-Gaussian beam emitted by the reflective pure phase spatial light modulator 205, and includes an obstacle 301, a turbulent phase screen 302 and a second non-polarizing beam splitter 303 arranged in sequence. The second non-polarizing beam splitter 303 is used to split the l-order chaotic Bessel-Gaussian beam passing through the obstacle 301 and the turbulent phase screen 302. One of the l-order chaotic Bessel-Gaussian beams is coupled to the photodetector 306 through the fifth plano-convex lens 305, and the output end of the photodetector 306 is connected to the oscilloscope 307. The other l-order chaotic Bessel-Gaussian beam is coupled to the charge-coupled device 309 through the 4f observation system composed of the fourth plano-convex lens 304 and the sixth plano-convex lens 308.

[0042] The generation of chaotic Bessel light is divided into the generation of chaotic laser and the use of spatial light modulator to perform spatial phase modulation on chaotic Gaussian light to obtain a first-order chaotic Bessel-Gaussian beam. Then, obstacles and turbulent phase screens are set on the propagation path to simulate the real propagation environment.

[0043] Specifically, in the chaotic laser generation module, laser 101 is a Fabry-Perot single-mode semiconductor laser with a central wavelength of 850 nm. The focal length of the first plano-convex lens 102 is 5 mm, and the first non-polarizing beam splitter 103 is a 50:50 non-polarizing beam splitter. In the chaotic Bessel-Gaussian beam construction module, the focal length of the second plano-convex lens 203 is 25 mm, and the focal length of the third plano-convex lens 204 is 75 mm. The second non-polarizing beam splitter 303 is a 50:50 non-polarizing beam splitter. The focal length of the fourth plano-convex lens 304 is 25 mm, the focal length of the fifth plano-convex lens 305 is 5 mm, and the focal length of the sixth plano-convex lens 308 is 25 mm.

[0044] The present invention also provides a method for generating a turbulence-resistant chaotic Bessel-Gaussian beam, comprising the following steps:

[0045] Laser 101 generates laser light, which is collimated by a first plano-convex lens 102 and then passes through an adjustable continuous light attenuation mirror 104 and a dielectric film reflector 105. The laser light then returns to the interior of laser 101 and generates a chaotic Gaussian beam based on the disturbance of the light field.

[0046] A chaotic Gaussian beam is emitted from the first non-polarizing beam splitter 103, and its polarization state is adjusted by the half-wave plate 201 and the linear polarizer 202 so that it is aligned with the working direction of the reflective pure phase spatial light modulator 205. The beam is then expanded by the second plano-convex lens 203 and the third plano-convex lens 204 and propagates to the reflective pure phase spatial light modulator 205 loaded with a holographic phase pattern composed of a spiral phase superimposed on a radially distributed pyramidal phase, thereby obtaining a first-order chaotic Bessel-Gaussian beam.

[0047] A first-order chaotic Bessel-Gaussian beam passed through an obstacle 301 and a turbulent phase screen 302, and was split 50:50 by a second non-polarizing beam splitter 303. One of the first-order chaotic Bessel-Gaussian beams was coupled to a photodetector 306 via a fifth plano-convex lens 305. An oscilloscope 307 was used to monitor the chaotic state of laser 101. The other first-order chaotic Bessel-Gaussian beam was coupled to a charge-coupled device 309 via a fourth plano-convex lens 304 and a sixth plano-convex lens 308, forming a 4f observation system. The lateral intensity distribution of the chaotic Bessel-Gaussian beam was observed. Obstacles and turbulent phase screens were placed along the propagation path to verify the self-healing and turbulence-resistant robustness of the chaotic Bessel-Gaussian beam.

[0048] In this embodiment, the generation of chaotic semiconductor laser is due to the coupling of the feedback light field with the laser cavity light field, which destroys the balance between the carrier and photon interaction in the laser cavity, thereby causing unstable laser output. The laser output state depends on the feedback delay time and feedback intensity. Under the appropriate feedback intensity, the laser can excite a chaotic state.

[0049] Diffraction-free (Bessel) beams are exact solutions to the wave equation in free space, which means they do not experience lateral expansion during propagation, that is, they maintain their intensity distribution during propagation. Bessel beams have infinitely expanding sidelobes, but this is unrealistic in reality. Usually, a Bessel-Gauss (BG) beam is used to generate an approximate Bessel beam, which is defined as:

[0050]

[0051] Where ω0 is the beam waist of the Gaussian beam that limits the BG beam. Indicates that its wavefront is a spiral wavefront, which means that the BG beam carries orbital angular momentum (OAM) Where l is an integer. When l=0, the field is The transverse intensity distribution of r and r is shown as a bright spot surrounded by concentric circles that gradually darken when projected onto the transverse plane. They are the radial and azimuthal coordinates in the polar coordinate system, z is the axial propagation distance, k z is the transverse component of the wave vector cone of the Bessel beam, k r is the longitudinal component, so that k r 2 +k z 2 =k 2 , k is the wave number.

[0052] The complex amplitude expression of the chaotic Bessel-Gaussian beam can be derived as follows:

[0053]

[0054] Where A(t), exp(-iφ), and exp(-iwt) are the time-dependent field amplitude, phase, and carrier, respectively.

[0055] After the generation of the l-order chaotic Bessel-Gaussian beam, the self-healing characteristics are simulated and experimentally verified.

[0056] The self-healing simulation process involves extracting the intensity and phase information of a chaotic laser at a specific point in time to construct a chaotic Bessel-Gaussian beam field. A blazed grating is used to simulate an opaque circular obstacle blocking the light field at the source. The angular spectrum method is used to perform Fresnel diffraction propagation, and the self-healing properties along the propagation path are observed.

[0057] The experimental verification process is as follows: an opaque obstacle 301 is used to block the chaotic Bessel-Gaussian beam on the propagation path and its self-healing properties are observed.

[0058] After the generation of the l-order chaotic Bessel-Gaussian beam, the robustness verification of the chaotic Bessel-Gaussian beam in a turbulent environment is also included:

[0059] The modified Von Karman spectrum model is used as the turbulence phase screen power spectral density model. Multiple turbulence phase screens are placed on the propagation path to simulate the light field distortion and drift caused by the real environment, which leads to random attenuation of the received optical power. The actual model is given by the following formula:

[0060]

[0061] where fm =5.92 / l0 and f0=2π / L0, l0 and L0 are the inner and outer scales respectively, f is the angular spatial frequency, is a refractive index structure parameter used to measure the local turbulence intensity. In the present invention, the light beam propagates along a horizontal path with a length of 300m. It is a moderate turbulence.

[0062] Figures 2 to 6 Figure 2 shows the timing, spectrum, optical field, and phase distribution of chaotic Bessel-Gaussian beams carrying different orders of orbital angular momentum. The unique phase distribution of the OAM helical structure ensures the orthogonality of different OAM beams. Theoretically, OAM multiplexing possesses infinite degrees of freedom in free space. Therefore, chaotic Bessel-Gaussian beams can not only improve beam robustness but also provide additional degrees of freedom for the expansion of chaotic secure communications.

[0063] Figure 4 (a), (b), (c), and (d) are the lateral intensity distributions of the 0-3 order chaotic Bessel-Gaussian beams captured experimentally;

[0064] Figure 5 (a), (b), (c), and (d) are the simulated lateral intensity distributions of 0-3 order chaotic Bessel-Gaussian beams;

[0065] Figure 6 (a), (b), (c), and (d) are the simulated phase distributions of 0-3 order chaotic Bessel-Gaussian beams, respectively.

[0066] Figure 7 、 Figure 8 The self-healing light field of a chaotic Bessel-Gaussian beam when there is an obstacle in the propagation path. After passing through the obstacle, the chaotic Bessel-Gaussian beam can still maintain a good phase wavefront and light intensity distribution.

[0067] Figure 7 (a), (b), and (c) are the self-healing light fields of the simulated chaotic Bessel-Gaussian beam when it passes through an obstacle on the propagation path;

[0068] Figure 8 (a), (b), and (c) are the self-healing light fields of the chaotic Bessel-Gaussian beam when there are real obstacles on the propagation path in the experiment.

[0069] Figure 9 、 Figure 10 Figure 3 shows the optical field distribution and power attenuation of a chaotic Bessel-Gaussian beam after passing through a turbulent phase screen. Compared to a chaotic Gaussian beam, a non-diffracting chaotic Bessel-Gaussian beam has lower power attenuation and can produce a more complete wavefront distribution on the receiving screen.

[0070] Figure 10 (b1) and (b2) are the light field distributions of chaotic Bessel-Gaussian beams at different propagation distances; (c1) and (c2) are the light field distributions of chaotic Gaussian beams at different propagation distances.

[0071] This paper theoretically analyzes and experimentally validates the feasibility of constructing chaotic Bessel-Gaussian beams, and further investigates their self-healing and turbulence-resistant propagation properties. The exceptional robustness of chaotic Bessel-Gaussian beams makes them a promising candidate for future chaotic free-space optical secure communications.

[0072] The foregoing description is merely a preferred embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any modifications or substitutions that can be readily conceived by a person skilled in the art within the technical scope disclosed herein should be included within the scope of protection of the present invention. Therefore, the scope of protection of the present invention should be based on the scope of protection of the claims.

Claims

1. A device for generating a turbulence-resistant chaotic Bessel-Gaussian beam, characterized in that: It includes a chaotic laser generation module, a chaotic Bessel-Gaussian beam construction module, and a chaotic Bessel-Gaussian beam self-healing and anti-turbulence characteristic verification module; The chaotic laser generation module comprises a laser (101) and a first plano-convex lens (102), a first non-polarizing beam splitter (103), an adjustable continuous light attenuation mirror (104) and a dielectric film reflector (105) sequentially arranged along the laser emission path of the laser (101). The chaotic laser generation module is used to generate a chaotic Gaussian beam. The chaotic Bessel-Gaussian beam construction module is located on the path of the chaotic Gaussian beam emitted by the non-polarization beam splitter (103), and includes a half-wave plate (201), a linear polarizer (202), a second plano-convex lens (203), a third plano-convex lens (204), and a reflective pure phase spatial light modulator (205) arranged in sequence. The chaotic Bessel-Gaussian beam construction module is used to generate a l-order chaotic Bessel-Gaussian beam; The chaotic Bessel-Gaussian beam self-healing and anti-turbulence characteristic verification module is located on the path of a l-order chaotic Bessel-Gaussian beam emitted by a reflective pure phase spatial light modulator (205), and comprises an obstacle (301), a turbulent phase screen (302) and a second non-polarizing beam splitter (303) arranged in sequence. The second non-polarizing beam splitter (303) is used to split the l-order chaotic Bessel-Gaussian beam passing through the obstacle (301) and the turbulent phase screen (302). One of the l-order chaotic Bessel-Gaussian beams is coupled to a photodetector (306) via a fifth plano-convex lens (305), and an oscilloscope (307) is connected to the output end of the photodetector (306). The other l-order chaotic Bessel-Gaussian beam is coupled to a charge coupled device (309) via a 4f observation system composed of a fourth plano-convex lens (304) and a sixth plano-convex lens (308).

2. The device for generating a turbulence-resistant chaotic Bessel-Gaussian beam according to claim 1, characterized in that: In the chaotic laser generation module, the laser (101) is a Fabry-Perot single-mode semiconductor laser with a central wavelength of 850 nm, the focal length of the first plano-convex lens (102) is 5 mm, and the first non-polarizing beam splitter (103) is a 50:50 non-polarizing beam splitter.

3. The device for generating a turbulence-resistant chaotic Bessel-Gaussian beam according to claim 1, wherein: In the construction module of the chaotic Bessel-Gaussian beam, the focal length of the second plano-convex lens (203) is 25 mm, and the focal length of the third plano-convex lens (204) is 75 mm.

4. The device for generating a turbulence-resistant chaotic Bessel-Gaussian beam according to claim 1, wherein: The second non-polarizing beam splitter (303) is a 50:50 non-polarizing beam splitter, the focal length of the fourth plano-convex lens (304) is 25 mm, the focal length of the fifth plano-convex lens (305) is 5 mm, and the focal length of the sixth plano-convex lens (308) is 25 mm.

5. A method for generating a turbulence-resistant chaotic Bessel-Gaussian beam, based on the device for generating a turbulence-resistant chaotic Bessel-Gaussian beam according to any one of claims 1 to 4, characterized in that: The following steps are involved: The laser (101) generates laser light, which is collimated by a first plano-convex lens (102), and then returns to the interior of the laser (101) after passing through an adjustable continuous light attenuation mirror (104) and a dielectric film reflector (105). Based on the disturbance of the light field, a chaotic Gaussian beam is generated. A chaotic Gaussian beam is emitted from a first non-polarizing beam splitter (103), and its polarization state is adjusted by a half-wave plate (201) and a linear polarizer (202) so as to be consistent with the working direction of a reflective pure phase spatial light modulator (205). The beam is expanded by a second plano-convex lens (203) and a third plano-convex lens (204) and propagated to a reflective pure phase spatial light modulator (205) to obtain a first-order chaotic Bessel-Gaussian beam. A holographic phase pattern consisting of a spiral phase superimposed on a radially distributed angular cone phase is loaded on the reflective pure phase spatial light modulator (205); A l-order chaotic Bessel-Gaussian beam passes through an obstacle (301) and a turbulent phase screen (302), and is split 50:50 by a second non-polarizing beam splitter (303). One of the l-order chaotic Bessel-Gaussian beams is coupled to a photodetector (306) by a fifth plano-convex lens (305), and an oscilloscope (307) is used to monitor whether the laser (101) is operating in a chaotic state. Another l-order chaotic Bessel-Gaussian beam is coupled to a charge-coupled device (309) via a fourth plano-convex lens (304) and a sixth plano-convex lens (308) to form a 4f observation system, and the transverse light intensity distribution of the chaotic Bessel-Gaussian beam is observed.

6. The method for generating a turbulence-resistant chaotic Bessel-Gaussian beam according to claim 5, characterized in that: After the generation of the l-order chaotic Bessel-Gaussian beam, the self-healing characteristics are simulated and experimentally verified. The self-healing simulation process involves extracting the intensity and phase information of a chaotic laser at a specific point in time to construct a chaotic Bessel-Gaussian beam field. A blazed grating is used to simulate an opaque circular obstacle blocking the light field at the source. The angular spectrum method is used to perform Fresnel diffraction propagation, and the self-healing properties along the propagation path are observed. The experimental verification process is as follows: using an opaque obstacle (301) to block the chaotic Bessel-Gaussian beam on the propagation path and observing its self-healing characteristics.

7. The method for generating a turbulence-resistant chaotic Bessel-Gaussian beam according to claim 5, characterized in that: After the generation of the l-order chaotic Bessel-Gaussian beam, the robustness verification of the chaotic Bessel-Gaussian beam in a turbulent environment is also included: The modified Von Karman spectrum model is used as the power spectrum density model of the turbulent phase screen, and multiple turbulent phase screens are placed on the propagation path to simulate the light field distortion and drift caused by the real environment. The actual model is given by the following formula: where f m =5.92 / l0 and f0=2π / L0, l0 and L0 are the inner and outer scales respectively, f is the angular spatial frequency, is the refractive index structure parameter used to measure the local turbulence intensity.

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