A method and system for simulating thermal blooming effect of wide spectrum light beam atmospheric transmission

Abstract

The present application belongs to the field of wide spectrum laser atmospheric transmission evaluation, and particularly relates to a wide spectrum beam atmospheric transmission thermal blooming effect simulation method and system. The method comprises simulating linear effect complex amplitudes at different transmission distances under linear effect based on transmission scene parameters; calculating light intensity distribution factors at different transmission distances based on simulation results of the linear effect complex amplitudes at different transmission distances; calculating phase disturbances caused by thermal blooming effect based on transmission scene parameters and the light intensity distribution factors at different transmission distances; simulating complex amplitudes at different focal distances at different times based on the phase disturbances caused by thermal blooming effect; and calculating long-time average light intensity distribution based on simulation results of the complex amplitudes at different focal distances at different times. The present application realizes wide spectrum beam atmospheric transmission thermal blooming effect simulation by equivalent wide spectrum laser to single wavelength laser, based on wide spectrum beam light intensity distribution factors and wide spectrum beam and atmospheric interaction hydrodynamic equation set.

Description

TECHNICAL FIELD

[0001] The application belongs to the field of wide-spectrum laser atmospheric transmission evaluation, and particularly relates to a wide-spectrum light beam atmospheric transmission thermal blooming effect simulation method and system. BACKGROUND

[0002] The high-power laser atmospheric transmission thermal blooming effect refers to that the atmospheric absorption of the light beam energy causes the disturbance of the refractive index distribution of the atmosphere on the light path, and the refractive index distribution disturbance in turn affects the propagation of the light beam. The thermal blooming effect is closely related to the wavelength characteristics of the light beam, and the thermal blooming effects of different wavelengths of laser under the same atmospheric condition are different.

[0003] In recent years, with the development of fiber light source manufacturing technology and light beam synthesis technology, the wide-spectrum light beam atmospheric transmission thermal blooming effect is a hot issue in the field of laser atmospheric transmission evaluation. The significant feature of the wide-spectrum laser light source is that the power is distributed at multiple wavelengths, and the thermal blooming effect caused by the common heating of the atmosphere by all wavelengths of the wide-spectrum laser makes the thermal blooming effect mechanism of the wide-spectrum light beam different from that of the single-wavelength light beam. However, there is a lack of wide-spectrum light beam atmospheric transmission thermal blooming effect simulation method in the engineering of laser system optimization, optoelectronic station site evaluation, etc. SUMMARY

[0004] In view of the above problems, the application provides a wide-spectrum light beam atmospheric transmission thermal blooming effect simulation method, which equivalent the interaction process of the wide-spectrum light beam and the atmosphere to the interaction process of a single wavelength and the atmosphere by constructing the light intensity distribution factor of the wide-spectrum light beam, and establishes the two-dimensional distribution of the atmospheric refractive index disturbance and the phase disturbance caused by the thermal blooming effect at different transmission distances based on the fluid mechanics equation set of the interaction process of the wide-spectrum light beam and the atmosphere, so as to realize the simulation and simulation of the complex amplitude at the focal length at different times and obtain the long-time average light intensity distribution of the wide-spectrum light beam at the focal length.

[0005] The first object of the application is to provide a wide-spectrum light beam atmospheric transmission thermal blooming effect simulation method, which comprises:

[0006] Based on the transmission scene parameters, the complex amplitude of the linear effect at different transmission distances is simulated under the linear effect;

[0007] Based on the simulation results of the complex amplitude of the linear effect at different transmission distances, the light intensity distribution factor at different transmission distances is calculated;

[0008] Based on the transmission scene parameters and the light intensity distribution factor at different transmission distances, the phase disturbance caused by the thermal blooming effect is calculated;

[0009] Based on the phase disturbance caused by the thermal blooming effect, the complex amplitude at the focal length at different times is simulated and simulated;

[0010] Based on the simulation results of the complex amplitude at the focal length at different times, the long-time average light intensity distribution is calculated.

[0011] In specific embodiments of the present application, the transmission scenario parameters include the power spectral density of the wide spectrum light beam, the atmospheric absorption coefficient of different wavelengths at different transmission distances, the atmospheric extinction coefficient of different wavelengths at different transmission distances, the focal length, the wind speed vector, and the complex amplitude of the light source at the equivalent wavelength.

[0012] In specific embodiments of the present application, the simulation of the linear effect complex amplitude at different transmission distances under linear effect based on the transmission scenario parameters includes:

[0013] According to the power spectral density of the wide spectrum light beam in the transmission scenario parameters, the equivalent wavelength is calculated.

[0014] According to the atmospheric extinction coefficient of different wavelengths at different transmission distances in the transmission scenario parameters, the atmospheric transmittance at different transmission distances along the light path at the equivalent wavelength is calculated.

[0015] The focal length is segmented, and the linear effect complex amplitude distribution at different transmission distances is simulated according to the atmospheric transmittance at different transmission distances along the light path at the equivalent wavelength.

[0016] In specific embodiments of the present application, the calculation formula of the light intensity distribution factor is as follows:

[0017]

[0018] wherein, is the light intensity distribution factor, is the equivalent wavelength, represents the laser transmission distance, represents the focal length is divided into the end point of the segment, is the transverse coordinate vector perpendicular to the light path at is the atmospheric transmittance at the equivalent wavelength of the light source power spectral density of the light beam, is the atmospheric transmittance at the equivalent wavelength of the light beam along the light path transmission distance z i at the equivalent wavelength is the linear effect complex amplitude of the light beam at the equivalent wavelength at the light path transmission distance .

[0019] In specific embodiments of the present application, the calculation of the phase disturbance caused by the thermal blooming effect based on the transmission scenario parameters and the light intensity distribution factor at different transmission distances includes:

[0020] According to the light intensity distribution factor at different transmission distances, and the power spectral density in the transmission scene parameters, the atmospheric absorption coefficient of different wavelengths at different transmission distances, and the atmospheric transmittance, wind speed vector, the refractive index perturbation at any time is calculated;

[0021] According to the refractive index perturbation at any time, the phase perturbation caused by thermal blooming effect is calculated.

[0022] In specific embodiments of the present application, the refractive index perturbation at any time is calculated according to the following formula:

[0023]

[0024] wherein, λ represents the wavelength, is the differential symbol, represents the partial derivative of time , and represents the refractive index relative to the temperature change rate, represents the atmospheric temperature, is the average value of atmospheric density, represents the wind speed vector perpendicular to the light path, is the specific heat capacity of constant pressure atmosphere, is the thermal conductivity coefficient, is the expression of the light source power spectral density of the light beam, is the maximum value of the power spectral distribution wavelength, is the minimum value of the power spectral distribution wavelength, is the expression of the atmospheric absorption coefficient of the light beam along the light path transmission distance z i , is the expression of the atmospheric transmittance of the light beam along the light path transmission distance z i , is the light intensity distribution factor.

[0025] In specific embodiments of the present application, the calculation formula of the phase perturbation caused by thermal blooming effect is as follows:

[0026]

[0027] wherein, the light transmission period is divided into segments, the end time of the th segment, is the refractive index perturbation at any time is the equivalent wavelength, , represents the focal length is divided into the end of the paragraph the end of the paragraph

[0028] In the embodiment of the present application, the long-time average light intensity distribution is calculated based on the simulation results of the complex amplitude at the focal length at different times, comprising:

[0029] The complex amplitude at the focal length is calculated according to the simulation results of the complex amplitude at the focal length at different times.

[0030] The long-time average light intensity distribution is obtained by squaring the complex amplitude at the focal length and averaging over time.

[0031] The second object of the present application is to provide a wide spectrum light beam atmospheric transmission thermal halo effect simulation system, comprising:

[0032] The first simulation module is used to simulate the linear effect complex amplitude at different transmission distances under linear effect based on the transmission scene parameters.

[0033] The first calculation module is used to calculate the light intensity distribution factor at different transmission distances based on the simulation results of the linear effect complex amplitude at different transmission distances.

[0034] The second calculation module is used to calculate the phase disturbance caused by thermal halo effect based on the transmission scene parameters and the light intensity distribution factor at different transmission distances.

[0035] The second simulation module is used to simulate and simulate the complex amplitude at the focal length at different times based on the phase disturbance caused by thermal halo effect.

[0036] The third calculation module is used to calculate the long-time average light intensity distribution based on the simulation results of the complex amplitude at the focal length at different times.

[0037] In the embodiment of the present application, the first simulation module comprises a preprocessing module and an execution module.

[0038] The preprocessing module is used to calculate the equivalent wavelength according to the power spectral density of the wide spectrum light beam in the transmission scene parameters, and is also used to calculate the atmospheric transmittance at different transmission distances along the light path at the equivalent wavelength according to the atmospheric extinction coefficient of different wavelengths at different transmission distances in the transmission scene parameters.

[0039] The execution module is used to segment the focal length, and simulate and simulate the linear effect complex amplitude at different transmission distances under linear effect according to the atmospheric transmittance at different transmission distances along the light path at the equivalent wavelength.

[0040] The beneficial effects of the present application are:

[0041] The simulation method and system of the thermal blooming effect of the wide spectrum light beam atmospheric transmission according to the present application, aiming at the significant characteristic that the power spectrum density of the wide spectrum light beam source is distributed on multiple wavelengths, equivalent the wide spectrum laser to single wavelength laser, firstly, the linear effect complex amplitude under the diffraction and attenuation effect is calculated, but considering the different strength of the thermal blooming effect of the laser of different wavelengths, the light intensity distribution factor of the wide spectrum light beam is further constructed, and based on the light intensity distribution factor of the wide spectrum light beam, the interaction process between the wide spectrum light beam and the atmosphere is equivalent to the interaction process between single wavelength and the atmosphere, and based on the fluid mechanics equation set of the interaction process between the wide spectrum light beam and the atmosphere, the two-dimensional distribution of the atmospheric refractive index disturbance and the phase disturbance caused by the thermal blooming effect at different transmission distances is established, so as to simulate and simulate the thermal blooming effect of the wide spectrum light beam atmospheric transmission, realize the simulation of the complex amplitude at different focal lengths at different times, and obtain the long-time average light intensity distribution of the wide spectrum light beam at the focal length of the atmospheric transmission.

[0042] Other features and advantages of the present application will be set forth in the following description, and in part will become apparent to those skilled in the art from the description, or can be learned by practice of the present application. The objects and other advantages of the present application can be realized and achieved by the structures indicated in the specification, claims and drawings. BRIEF DESCRIPTION OF DRAWINGS

[0043] In order to more clearly illustrate the technical solutions in the embodiments of the present application or the prior art, the following will briefly introduce the drawings needed to be used in the embodiments or prior art description. Obviously, the drawings in the following description are some embodiments of the present application, and those skilled in the art can also obtain other drawings according to these drawings without creative labor.

[0044] Figure 1 The flow chart of a simulation method of the thermal blooming effect of the wide spectrum light beam atmospheric transmission according to an embodiment of the present application is shown;

[0045] Figure 2 The power spectrum density distribution of the wide spectrum light beam source according to an embodiment of the present application is shown;

[0046] Figure 3 The atmospheric extinction coefficient data and the atmospheric transmittance data graph according to an embodiment of the present application are shown; wherein, Figure 3 In (a), the atmospheric extinction coefficient of the light beam corresponding to different wavelengths along the light path at different transmission distances, Figure 3 In (b), the atmospheric transmittance of 1060 nanometer wavelength along the light path at different transmission distances;

[0047] Figure 4 The light source complex amplitude distribution at the equivalent wavelength according to an embodiment of the present application is shown, wherein Figure 4 In (a), the light source amplitude distribution at the equivalent wavelength of 1060 nanometers, Figure 4(b) is the phase distribution at the equivalent wavelength 1060 nm;

[0048] Figure 5 The light intensity distribution factor at different transmission distances according to the embodiment of the application is shown, wherein, Figure 5 (b) is the light intensity distribution factor at the transmission distance 1.4 km, Figure 5 (b) is the light intensity distribution factor at the transmission distance 1.4 km, Figure 5 (b) is the light intensity distribution factor at the transmission distance 1.4 km, Figure 5 (b) is the light intensity distribution factor at the transmission distance 1.4 km;

[0049] Figure 6 The atmospheric absorption coefficient data according to the embodiment of the application is shown;

[0050] Figure 7 The phase disturbance caused by thermal blooming effect at different transmission distances according to the embodiment of the application is shown, wherein, Figure 7 (b) is the phase disturbance caused by thermal blooming effect at the transmission distance 1.4 km, Figure 7 (b) is the phase disturbance caused by thermal blooming effect at the transmission distance 1.4 km, Figure 7 (b) is the phase disturbance caused by thermal blooming effect at the transmission distance 1.4 km, Figure 7 (b) is the phase disturbance caused by thermal blooming effect at the transmission distance 1.4 km;

[0051] Figure 8 The long-time average light intensity distribution diagram at the atmospheric transmission focal length of the wide-spectrum light beam according to the embodiment of the application is shown;

[0052] Figure 9 The framework diagram of a wide-spectrum light beam atmospheric transmission thermal blooming effect simulation system according to the embodiment of the application is shown;

[0053] In the figure: 10, first simulation module; 20, first calculation module 20; 30, second calculation module; 40, second simulation module; 50, third calculation module. DETAILED DESCRIPTION

[0054] In order to make the purpose, technical scheme and advantages of the embodiments of the application clearer, the technical scheme in the embodiments of the application will be clearly and completely described below with reference to the drawings in the embodiments of the application. Obviously, the described embodiments are part of the embodiments of the application, rather than all the embodiments of the application. Based on the embodiments in the application, all other embodiments obtained by those skilled in the art without creative labor fall within the scope of protection of the application.

[0055] As Figure 1 shown, a wide spectrum light beam atmospheric transmission thermal blooming effect simulation method according to some embodiments of the present application comprises:

[0056] S1, based on transmission scene parameters, equivalent a wide spectrum light source to a single wavelength light source, simulate linear effect complex amplitude at different transmission distances under linear effect;

[0057] S2, based on simulation results of linear effect complex amplitude at different transmission distances, calculate light intensity distribution factors at different transmission distances;

[0058] S3, based on transmission scene parameters, and light intensity distribution factors at different transmission distances, calculate phase disturbance caused by thermal blooming effect;

[0059] S4, based on phase disturbance caused by thermal blooming effect, simulate complex amplitude at different focal distances at different times;

[0060] S5, based on simulation results of complex amplitude at different focal distances at different times, calculate long-time average light intensity distribution.

[0061] In some embodiments of the present application, in step S1, the transmission scene parameters include power spectral density of the wide spectrum light beam, atmospheric absorption coefficient of different wavelengths at different transmission distances, atmospheric extinction coefficient of different wavelengths at different transmission distances, focal distance, wind speed vector, light source complex amplitude at equivalent wavelength.

[0062] In some embodiments of the present application, step S1 comprises:

[0063] S1-1, according to power spectral density of the wide spectrum light beam in the transmission scene parameters, calculate the equivalent wavelength; the light source power spectral density is , the equivalent wavelength The expression is shown as formula (1):

[0064] (1)

[0065] Wherein, represents the wavelength, is the minimum wavelength value, is the maximum wavelength value.

[0066] S1-2, according to atmospheric extinction coefficient of different wavelengths at different transmission distances in the transmission scene parameters, calculate atmospheric transmittance at different transmission distances along the light path at the equivalent wavelength; wherein, the atmospheric extinction coefficient corresponding to different wavelengths is , the atmospheric transmittance at the equivalent wavelength at different transmission distances The calculation formula is shown as formula (2):

[0067] (2)

[0068] wherein, denotes an exponential operation, denotes a laser transmission distance, denotes a focal length is divided into the end point of the the end point of the

[0069] S1-3, the focal length is divided into segments, and the linear effect complex amplitude distribution at different transmission distances is simulated according to the atmospheric transmittance at the equivalent wavelength along the optical path at different transmission distances.

[0070] the focal length is divided into segments, is the end point of the segment, and is calculated according to the light wave Fresnel diffraction theory under the paraxial approximation, and the specific simulation and calculation formula is shown in formula (3):

[0071] (3)

[0072] in formula (3), is a transverse coordinate vector perpendicular to the optical path at , the equivalent wavelength is , the atmospheric transmittance of the light beam along the optical path transmission distance at z i , is the linear effect complex amplitude of the light beam with the equivalent wavelength at the transmission distance , , denotes a Fourier transform, and j is a complex symbol, is the light source complex amplitude of the light beam with the equivalent wavelength at the transmission distance z 0.

[0073] In step S1, some embodiments of the present application equivalently convert a wide-spectrum light source into a single-wavelength light source to simulate the linear effect complex amplitude at different transmission distances under linear effect.

[0074] In some embodiments of the present application, in step S2, the calculation formula of the light intensity distribution factor is shown in formula (4):

[0075] (4)

[0076] in formula (4), is a light intensity distribution factor, is a linear effect complex amplitude at different transmission distances;​​ the equivalent wavelength , the equivalent wavelength is the atmospheric transmittance of the light beam at the equivalent wavelength .

[0077] In some embodiments of the present application, step S3 comprises:

[0078] S3-1, calculating the refractive index perturbation at any moment according to the light intensity distribution factor at different transmission distances, and the power spectral density, the atmospheric absorption coefficient of different wavelengths at different transmission distances, the atmospheric transmittance, and the wind speed vector in the transmission scene parameters;

[0079] S3-2, calculating the phase perturbation caused by thermal blooming effect according to the refractive index perturbation at any moment.

[0080] In some embodiments of the present application, in step S3-1, in the process of calculating the refractive index perturbation at any moment, the calculation formula of the refractive index perturbation at any moment is derived according to the theory of fluid mechanics, and the specific derivation process is as follows:

[0081] According to the theory of fluid mechanics, the light beam with wavelength and complex amplitude satisfies the fluid mechanics equation set (5) when interacting with the atmosphere:

[0082] (5)

[0083] In formula (5), represents the atmospheric temperature, and are the average value and the perturbation value of the atmospheric density, and are the average value and the perturbation value of the atmospheric pressure, represents the wind speed vector perpendicular to the light path, is the specific heat capacity of the atmosphere at constant pressure, is the thermal conductivity, is the ratio of the specific heat at constant pressure to the specific heat at constant volume.

[0084] Replace with the function of the light intensity distribution factor, which is shown in formula (6):

[0085] (6)

[0086] Under the isobaric approximation, formula (6) is brought into the above fluid mechanics equation set (5) to obtain formula (7):

[0087] (7)

[0088] In formula (7), is the refractive index perturbation caused by the light beam with wavelength .

[0089] The refractive index perturbation caused by the thermal blooming effect of the wide spectrum light beam is the integral of the wavelength, as shown in formula (8):

[0090] (8)

[0091] Integrating formula (8) in the power spectral density wavelength range, the calculation formula of the refractive index perturbation at any moment caused by the thermal blooming effect is obtained, which is shown in formula (9):

[0092] (9)

[0093] In formula (9), is the refractive index perturbation caused by the atmospheric transmission thermal blooming effect of the wide spectrum light beam, represents the relative temperature change rate of the refractive index.

[0094] Ignoring the difference of the light intensity distribution factors of different wavelengths, the light intensity distribution factors of different wavelengths are replaced by , then formula (9) is transformed into formula (10):

[0095] (10)

[0096] In formula (10), is the refractive index perturbation at any moment, represents the relative temperature change rate of the refractive index, represents the atmospheric temperature, is the average value of the atmospheric density, represents the wind speed vector perpendicular to the light path, is the specific heat capacity of the constant pressure atmosphere, is the thermal conductivity coefficient, is the expression of the light source power spectral density of the light beam, is the maximum value of the power spectral distribution wavelength, is the minimum value of the power spectral distribution wavelength, is the expression of the atmospheric absorption coefficient of the light beam at the light path transmission distance . z i is the expression of the atmospheric absorption coefficient of the light beam at the light path transmission distance . z i is the atmospheric transmittance of the light beam at the light path transmission distance .

[0097] In some embodiments of the present application, in the step S3-2, the phase disturbance caused by thermal blooming The calculation formula is shown in equation (11):

[0098] (11)

[0099] In equation (11), represents that the light transmission period is divided into the first the end time of the is the equivalent wavelength.

[0100] In some embodiments of the present application, in the step S4, the simulation of the complex amplitude at the focal length at different times is carried out according to the light wave Fresnel diffraction theory under the paraxial approximation, and the specific simulation calculation formula is shown in equation (12):

[0101] (12)

[0102] In equation (12), .

[0103] The phase disturbance caused by thermal blooming at different times is brought into equation (12), and the complex amplitude at the focal length can be calculated. .

[0104] In some embodiments of the present application, in the step S5, the value obtained by averaging the complex amplitude at the focal length with respect to time is taken as the long-time average light intensity distribution, and the specific expression is shown in equation (13).

[0105] (13)

[0106] In steps S2-S5, some embodiments of the present application consider the difference in the strength of thermal blooming of different wavelengths of laser, and by constructing the light intensity distribution factor of the wide spectrum light beam, the wide spectrum light beam and the atmospheric interaction process are equivalent to the single wavelength and the atmospheric interaction process, but in the simulation process, based on the wide spectrum light beam and the atmospheric interaction hydrodynamic equation set, the two-dimensional distribution of the atmospheric refractive index disturbance and the phase disturbance caused by thermal blooming at different transmission distances is established, the simulation of the complex amplitude at the focal length at different times is realized, and the long-time average light intensity distribution of the wide spectrum light beam at the focal length is obtained.

[0107] According to the wide spectrum light beam atmospheric transmission thermal blooming simulation method provided in the above embodiments, a specific spectrum light beam atmospheric transmission thermal blooming simulation example is carried out, and the specific process is as follows:

[0108] Step S1 is carried out:

[0109] Figure 2 The power spectral density of the light source is shown Data, minimum wavelength Nanometers, maximum wavelength Nanometers; based on the power spectral density of the light source Data, calculate the equivalent wavelength, get the equivalent wavelength of 1064 nanometers;

[0110] Figure 3 (a) shows the atmospheric extinction coefficient corresponding to different wavelengths , Figure 3 (b) shows the atmospheric transmittance of 1060 nanometer wavelength at different transmission distances.

[0111] Figure 4 (a) shows the complex amplitude of the light source at the equivalent wavelength of 1064 nanometers Amplitude distribution, Figure 4 (b) shows the phase distribution of the complex amplitude of the light source at the equivalent wavelength of 1064 nanometers Focal length Kilometers, divided into 22 segments, i.e. According to formula (3), the linear effect complex amplitude at different transmission distances along the light path is simulated.

[0112] Step S2 is performed:

[0113] According to the simulation results of the complex amplitude at different transmission distances obtained in step S1, and formula (4), the light intensity distribution factor at different transmission distances is calculated, Figure 5 The light intensity distribution factor at different transmission distances is shown.

[0114] Step S3 is performed:

[0115] Based on the light intensity distribution factor obtained in step S2, and the atmospheric absorption coefficient at different transmission distances along the light path and the atmospheric transmittance of the light beam along the light path at different transmission distances, the refractive index disturbance caused by thermal blooming effect at any time Is calculated by formula (10). In the calculation, the atmospheric absorption coefficient is as shown in Figure 6 The atmospheric temperature is 303.15 Kelvin, the X-direction wind speed is 3 meters / second, the Y-direction wind speed is 0 meters / second, the laser is continuously emitted for 0.1 seconds, which is equally divided into 10 time periods.

[0116] The phase disturbance at different times is calculated by formula (11). Figure 7 The phase disturbance caused by thermal blooming effect at different transmission distances at 52.4 milliseconds is given.

[0117] Step S4 is performed:

[0118] Based on the phase disturbance caused by thermal blooming effect obtained in step S3, the complex amplitude at the focal length at different time is simulated according to formula (12); and the phase disturbance caused by thermal blooming effect at different time is brought in The complex amplitude at the focal length .

[0119] Step S5 is performed:

[0120] The long-time average light intensity distribution is calculated according to formula (13) , and the specific long-time average light intensity distribution is shown in Figure 8 .

[0121] As shown in Figure 9 , a wide spectrum light beam atmospheric transmission thermal blooming effect simulation system according to some embodiments of the present application comprises:

[0122] A first simulation module 10 is configured to simulate the linear effect complex amplitude at different transmission distances under linear effect based on transmission scene parameters;

[0123] A first calculation module 20 is configured to calculate the light intensity distribution factor at different transmission distances based on the simulation results of the linear effect complex amplitude at different transmission distances;

[0124] A second calculation module 30 is configured to calculate the phase disturbance caused by thermal blooming effect based on transmission scene parameters and the light intensity distribution factor at different transmission distances;

[0125] A second simulation module 40 is configured to simulate the complex amplitude at the focal length at different time based on the phase disturbance caused by thermal blooming effect;

[0126] A third calculation module 50 is configured to calculate the long-time average light intensity distribution based on the simulation results of the complex amplitude at the focal length at different time.

[0127] In some embodiments of the present application, the first simulation module 10 comprises a preprocessing module and an execution module;

[0128] The preprocessing module is configured to calculate the equivalent wavelength according to the power spectral density of the wide spectrum light beam in the transmission scene parameters, and to calculate the atmospheric transmittance at different transmission distances along the light path at the equivalent wavelength according to the atmospheric extinction coefficient of different wavelengths at different transmission distances in the transmission scene parameters;

[0129] The execution module is configured to segment the focal length, and to simulate the linear effect complex amplitude at different transmission distances under linear effect according to the atmospheric transmittance at different transmission distances along the light path at the equivalent wavelength.

[0130] ​Although the present application has been described in detail with reference to the foregoing embodiments, it should be understood that modifications can be made to the foregoing embodiments, or additional implementations can be implemented, without departing from the spirit and scope of the inventive subject matter. Accordingly, the present application is not limited to the implementations described herein, but is intended to be defined by the claims set forth below, and equivalents thereof.

Claims

1. A method for simulating thermal blooming effect of atmospheric transmission of a wide spectrum light beam, characterized in that, The method comprises the following steps: Simulating the complex amplitude of linear effect at different transmission distances based on transmission scenario parameters; Calculating the light intensity distribution factor at different transmission distances based on the simulation results of the complex amplitude of linear effect at different transmission distances; Calculating the phase disturbance caused by thermal blooming effect based on the transmission scenario parameters and the light intensity distribution factor at different transmission distances; Simulating the complex amplitude at the focal length at different times based on the phase disturbance caused by thermal blooming effect; Calculating the long-time average light intensity distribution based on the simulation results of the complex amplitude at the focal length at different times; The calculation formula of the light intensity distribution factor is as follows: wherein is the light intensity distribution factor, is the equivalent wavelength, denotes the laser propagation distance, denotes the focal length is divided into the end of the segment, is the transversal coordinate vector perpendicular to the optical path at is the equivalent wavelength is the light source power spectral density of the light beam, is the equivalent wavelength is the linear effect complex amplitude of the light beam at the propagation distance z i along the optical path at is the equivalent wavelength is the linear effect complex amplitude of the light beam at the propagation distance along the optical path at The calculation of the long-time average light intensity distribution based on the simulation results of the complex amplitude at the focal length at different times comprises: According to the simulation results of the complex amplitude at the focal length at different times, the complex amplitude at the focal length is calculated; The long-time average light intensity distribution is calculated by squaring the complex amplitude at the focal length and averaging the result over time.

2. The method of claim 1, wherein, The transmission scenario parameters include the power spectral density of the wide-spectrum light beam, the atmospheric absorption coefficient of different wavelengths at different transmission distances, the atmospheric extinction coefficient of different wavelengths at different transmission distances, the focal length, the wind speed vector, and the complex amplitude of the light source at the equivalent wavelength.

3. The method of claim 1, wherein, The simulation of the complex amplitude of linear effect at different transmission distances based on the transmission scenario parameters comprises: According to the power spectral density of the wide-spectrum light beam in the transmission scenario parameters, the equivalent wavelength is calculated; According to the atmospheric extinction coefficient of different wavelengths at different transmission distances in the transmission scenario parameters, the atmospheric transmittance at different transmission distances along the light path at the equivalent wavelength is calculated; The focal length is segmented, and the complex amplitude distribution of linear effect at different transmission distances is simulated based on the atmospheric transmittance at different transmission distances along the light path at the equivalent wavelength.

4. The method of claim 1, wherein, The calculation of the phase disturbance caused by thermal blooming effect based on the transmission scenario parameters and the light intensity distribution factor at different transmission distances comprises: According to the light intensity distribution factor at different transmission distances and the power spectral density, the atmospheric absorption coefficient of different wavelengths at different transmission distances, the atmospheric transmittance, and the wind speed vector in the transmission scenario parameters, the refractive index disturbance at any time is calculated; According to the refractive index disturbance at any time, the phase disturbance caused by thermal blooming effect is calculated.

5. The method of claim 4, wherein, the radiometric disturbance at the arbitrary instant is calculated according to the following formula: wherein, denotes the rate of change of the refractive index with respect to temperature, denotes the atmospheric temperature, is the average value of the atmospheric density, denotes the wind speed vector perpendicular to the optical path, is the specific heat capacity of the atmosphere at constant pressure, is the thermal conductivity, is the expression of the light source power spectral density of the optical beam, is the maximum value of the power spectral distribution wavelength, is the minimum value of the power spectral distribution wavelength, is the optical path transmission distance of the optical beam, z i is the expression of the atmospheric absorption coefficient at the point, is the optical path transmission distance of the optical beam, z i is the expression of the atmospheric transmittance at the point, is the light intensity distribution factor.

6. The method of claim 4, wherein, The calculation formula of the phase disturbance caused by thermal blooming effect is as follows: wherein, denotes the interval between the light transmission periods is divided into the first the end of the interval, is an arbitrary time is the emissivity perturbation, is the equivalent wavelength, , denotes the focal length is divided into the first the end of the interval.

7. A system for simulating thermal blooming effects of atmospheric propagation of a broad spectrum light beam, characterized in that, The method comprises the following steps: A first simulation module is used to simulate the complex amplitude of linear effect at different transmission distances based on transmission scenario parameters; A first calculation module is used to calculate the light intensity distribution factor at different transmission distances based on the simulation results of the complex amplitude of linear effect at different transmission distances; A second calculation module is used to calculate the phase disturbance caused by thermal blooming effect based on the transmission scenario parameters and the light intensity distribution factor at different transmission distances; A second simulation module is used to simulate the complex amplitude at the focal length at different times based on the phase disturbance caused by thermal blooming effect; A third calculation module is used to calculate the long-time average light intensity distribution based on the simulation results of the complex amplitude at the focal length at different times; The calculation formula of the light intensity distribution factor is as follows: wherein is the light intensity distribution factor, is the equivalent wavelength, denotes the laser propagation distance, denotes the focal length is divided into the end of the the end of the is is the transversal coordinate vector perpendicular to the optical path at is the equivalent wavelength is the light source power spectral density of the light beam, is the equivalent wavelength is the linear effect complex amplitude of the light beam at the propagation distance z i is the atmospheric transmittance at is the equivalent wavelength is the linear effect complex amplitude of the light beam at the propagation distance is the atmospheric transmittance at The calculation of the long-time average light intensity distribution based on the simulation results of the complex amplitude at the focal length at different times comprises: According to simulation results of the complex amplitude at the focal length at different times, the complex amplitude at the focal length is calculated; The value obtained by squaring the complex amplitude at the focal length and averaging over time is taken as the long-time average light intensity distribution.

8. The system of claim 7, wherein the system further comprises a thermal blooming effect simulation module configured to simulate a thermal blooming effect of the wide spectrum light beam propagating through the atmosphere. The first simulation module comprises a preprocessing module and an execution module; The preprocessing module is used to calculate the equivalent wavelength according to the power spectral density of the wide spectrum light beam in the transmission scene parameters, and is also used to calculate the atmospheric transmittance at different transmission distances along the light path at the equivalent wavelength according to the atmospheric extinction coefficients of different wavelengths at different transmission distances in the transmission scene parameters; The execution module is used to segment the focal length, and simulate and analyze the linear effect complex amplitude at different transmission distances under the linear effect according to the atmospheric transmittance at different transmission distances along the light path at the equivalent wavelength.

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