CN101968567B - Novel self-adaptive optical method and system of wavefront-free sensor - Google Patents

Abstract

The invention provides a novel adaptive optics method and system without a wavefront sensor. The method includes the steps of establishing an initial wavefront, constructing a coupling efficiency evaluation function, acquiring tilt compensation signals and reconstructing wavefront matrix information, determining the best position of a guide mirror, and adjusting the reconstructed wavefront matrix and tilt compensation signals through a control loop. The system is mainly composed of an optical receiving aperture lens (1), a beam collimating lens (2), a first converging lens (3), a spatial light modulator, a collimating lens (4), a guide mirror, and a second converging lens (5 ) and a photodetector (6), which are sequentially connected with optical path signals. The application of the system in high-speed space optical communication or optical imaging. The invention can improve the reliability of the communication system, conforms to the characteristics of the free space optical communication system, has strong practicability, and is convenient for popularization and application.

Description

Novel adaptive optics method and system without wavefront sensor

technical field

The invention relates to the optical field wavefront distortion compensation system technology in the field of optical communication technology and adaptive optics technology, in particular to a novel adaptive optics method and system without a wavefront sensor.

Background technique

With the increasing amount of spatial data information, the demand for data transmission bandwidth is also increasing. The bandwidth advantage of space optical communication will make it the main technical solution for space science research, inter-satellite communication, satellite-ground communication, manned spaceflight, lunar exploration project and earth observation data transmission and exchange. The United States, France, Russia, Japan and other developed countries, as well as the European Community, included satellite payload technology in the space optical communication test plan as early as the 1970s, and carried out communication tests. Since then, space optical communication has been a research hotspot in the field of space science and aerospace technology.

Space optical communication requires flexible and convenient system, miniaturization, light weight and high reliability.

For space optical communication, on the space optical link, the factors that affect the reduction of the received signal strength are not only the direct attenuation of the atmospheric medium and the ordinary inverse attenuation of the optical transmission distance, but also closely related to the distribution of the physical parameters of the atmosphere in the optical communication link. . For example, for satellite-terrestrial optical communication links, the temperature distribution of the atmosphere of about 600 kilometers varies with altitude, and the speed of airflow is not uniform. The random distribution of air pressure and temperature in space causes the atmospheric refractive index It is also randomly distributed, which forms the so-called atmospheric turbulence. The turbulent atmosphere distorts the wavefront of the propagating light field, and the wavefront distortion causes the amplitude fluctuation of the optical signal, light deflection (deviation of the light propagation direction) and beam expansion, which also seriously attenuates the optical signal in terms of receiving effect, greatly reducing the The energy coupling efficiency from free space to the receiving fiber affects the communication quality. The physical mechanism causing this attenuation is completely different from the direct attenuation of the optical link and the inversely proportional distance attenuation. The physical process of the attenuation and signal fluctuation (scintillation) of the optical signal caused by atmospheric turbulence is essentially the wavefront phase of the transmitted light field being affected. Distortion occurs due to the action of turbulence. To eliminate or weaken the influence of this distortion, the wavefront distortion of the propagating light field must be compensated. Correcting the wavefront distortion of the propagating light field on the optical link is the most direct and effective technical solution to ensure the reliable implementation of long-distance broadband free-space optical communication, and an important means to improve and enhance the characteristics of free-space optical communication links. is of great significance.

Adaptive Optics (AO) technology is the most effective solution for real-time compensation of wavefront distortion caused by atmospheric turbulence, which has been best demonstrated in the application of space telescope systems and space target imaging systems. Although AO technology has been developed in the 1970s, it has only been applied in free space optical communication systems to improve communication quality in recent years. Free-space optical communication requires the use of AO technology to be fully adaptive, and the optical signal tracking response is fast. It also requires the system to be small in size and light in weight, which is quite different from the conventional or traditional AO used in astronomical telescope systems or space target imaging systems.

A conventional adaptive optics system is structurally composed of wavefront detection, wavefront reconstruction, wavefront correction, and phase conjugation compensation. The wavefront distortion compensation is implemented on the aperture plane. Wavefront detection and wavefront reconstruction require Completed separately, the whole constitutes a closed-loop control system. Applying this system to a free space optical communication system has the following deficiencies:

常规自适应光学（AO）系统（见图1）是一个线性时不变系统，其控制环路具有固定增益，这种控制环路采用了先验大气统计特性，典型处理方法是采用一种大气折射率结构常数Cn2模型，实际上并不是自适应的。因此，常规AO在算法方面表现出明显不足。AO在一些成像系统的应用中，为简便往往只考虑了惯性区域的湍流情况，其湍流尺度从几个毫米到几十毫米，而远距离空间光通信链路上，由光束发散角（如半导体激光器）导致的光束扩展区域达到米量级，这时，只考虑惯性区域就难以实现全天候通信！所用湍流大气模型的局限和控制回路的算法落后是常规AO不适合应用到自由空间光通信系统的关键原因！例如由于大气风速和湍流强度变化迅速，常规AO的固定增益补偿算法获得的波前补偿效果远不理想。2007年，B.L.ELLerbroek, J.S.Gibson 以及Y.T.Liu 等人研究了基于recursive least squares (RLS)优化重构矩阵的自适应波前重构算法，在这种算法中，虽然自适应控制环取代经典AO系统的反馈环，并在模型误差和传感器噪声较大时取得了较好效果，但实时性仍不够理想，响应速度仍不能满足空间光通信系统的快速要求。

The conventional adaptive optics (AO) system (see Fig. 1) is a linear time-invariant system, and its control loop has a fixed gain. This control loop adopts the prior statistical characteristics of the atmosphere. The typical processing method is to use an atmospheric The refractive index structure constant Cn2 model is not actually adaptive. Therefore, conventional AO shows obvious deficiencies in terms of algorithms. In the application of some imaging systems, AO often only considers the turbulence in the inertial region for simplicity, and its turbulence scale ranges from several millimeters to tens of millimeters. On long-distance space optical communication links, the beam divergence angle (such as Laser) the beam expansion area can reach the order of meters. At this time, it is difficult to achieve all-weather communication only considering the inertial area! The limitations of the turbulent atmospheric model used and the backward algorithm of the control loop are the key reasons why conventional AO is not suitable for application to free-space optical communication systems! For example, due to the rapid change of atmospheric wind speed and turbulence intensity, the wavefront compensation effect obtained by conventional AO fixed gain compensation algorithm is far from ideal. In 2007, BLELLerbroek, JSGibson and YTLiu et al. studied the adaptive wavefront reconstruction algorithm based on the recursive least squares (RLS) optimized reconstruction matrix. In this algorithm, although the adaptive control loop replaces the feedback loop of the classic AO system , and achieved good results when the model error and sensor noise are large, but the real-time performance is still not ideal, and the response speed still cannot meet the fast requirements of the space optical communication system.

波前传感器在强湍流时其波前检测性能大大下降，且因常规AO系统在孔径平面实施波前补偿，因而高阶畸变得不到补偿，因此，在远距离高速自由空间光通信系统中，常规AO对改善湍流大气引起的耦合能量衰减作用就不明显。

The wavefront detection performance of the wavefront sensor is greatly reduced under strong turbulence, and because the conventional AO system implements wavefront compensation on the aperture plane, the high-order distortion cannot be compensated. Therefore, in the long-distance high-speed free-space optical communication system, Conventional AO has little effect on improving the attenuation of coupling energy caused by turbulent atmosphere.

常规AO系统采用的是闭环控制，体积较大，算法复杂，响应速度慢。

The conventional AO system adopts closed-loop control, which is large in size, complex in algorithm, and slow in response.

As mentioned above, the application of AO system to free space optical communication needs to be redesigned and improved. The present invention is to realize high-speed, long-distance free-space optical communication, and is a novel self-adaptive optical technology conforming to the characteristics of the free-space optical communication system.

Contents of the invention

The technical problem to be solved by the present invention is to provide a novel adaptive optics method and system without a wavefront sensor for the above-mentioned problems existing in the long-distance free-space high-speed optical communication. The provided method can resist turbulent atmospheric interference, and the provided system can correct wavefront distortion, which is not only suitable for high-speed space optical communication, but also suitable for optical imaging, and is convenient for popularization and application.

The present invention solves its technical problem and adopts the following technical solutions:

The novel adaptive optics method without wavefront sensor provided by the present invention, it comprises the following steps:

a. Establish the initial wavefront:

Using statistical predictive analysis methods, specifically: performing variational processing on the refractive index structure functions of various turbulence models, using multi-layer turbulent atmospheric models, and then using the Zernik wavefront model to statistically analyze and set the reference initial wavefront in the circular domain ;

b. Construct the coupling efficiency evaluation function:

The coupling efficiency evaluation function is constructed from the signal output by the photodetector, specifically: according to the relationship between the signal output by the measured photodetector and the detection output signal corresponding to the initial wavefront, using the Strehl ratio on the field in step a, Establish the coupling efficiency evaluation function of the received light energy of the communication system, as one of the reference data for real-time adjustment of the wavefront reconstruction parameters;

c. Obtain tilt compensation signal and reconstructed wavefront matrix information:

In the wavefront reconstruction algorithm processor, the predicted wavefront and the coupling efficiency evaluation function are processed by the wavefront reconstruction algorithm combined with the RLS algorithm and the genetic algorithm, and the tilt compensation signal and the reconstructed wavefront matrix information are obtained;

d. Determine the best position of the guide mirror:

Reconstruct the wavefront matrix into 128×128 units to control the amount of information, drive the spatial light modulator, and implement compensation for the distorted wavefront; the tilt compensation signal drives the guide mirror to correct the beam deflection caused by the turbulent atmosphere, so as to improve the energy coupling efficiency ;

e. According to the energy coupling efficiency evaluation function, further judge and adjust the predicted wavefront, and reconstruct the wavefront matrix and tilt compensation signal through the control loop adjustment;

The above process is repeated until the maximum energy coupling efficiency is obtained, and the signal flicker caused by wavefront distortion is eliminated at the same time.

In step a, the initial wavefront can be used as a reference wavefront for wavefront correction, and will be adaptively adjusted in the subsequent wavefront reconstruction neural network genetic algorithm. The method of self-adaptive adjustment can also be: when the evaluation of the currently detected wavefront parameters according to the coupling efficiency evaluation function and the Strehl ratio does not reach the ideal state, then according to the current wavefront distortion obtained by the RLS algorithm and the genetic algorithm The evaluation parameters are adaptively adjusted to predict the initial wavefront parameters, and the wavefront is re-statistically predicted and reconstructed, and then the coupling efficiency and Strehl ratio are used as factors for evaluating and correcting the wavefront distortion, and so on until tolerable error.

In the step b, the signal output by the photodetector can be used as a reference for evaluating the strength of the signal received by the system, and at the same time as a reference for evaluating the wavefront distortion correction.

The specific method for realizing step c of the present invention may be: the tilt compensation signal and the wavefront reconstruction matrix information are respectively based on the coupling efficiency evaluation function and the initial wavefront information, and when the coupling efficiency is the highest, that is, when the coupling efficiency function reaches a maximum value, determine The tilt compensation reaches the optimum; and when the algorithm confirms that the Strehl ratio reaches the maximum and the coupling efficiency function reaches the maximum value through multiple iterations of the genetic algorithm, the information of the wavefront reconstruction matrix is determined accordingly.

The specific method for realizing step d of the present invention may be: after the parameters of the 128×128 wavefront reconstruction matrix are determined, convert the information of each unit of the matrix into a voltage drive signal, and drive the wavefront compensation device——spatial light modulator, to correct the distortion The wavefront is corrected, and the corrected wavefront information is sent to the algorithm processing unit, and the judgment is repeated until the Strehl ratio is the largest. At this time, it is determined that the wavefront correction meets the requirements; and the tilt compensation output signal obtained by the algorithm is Drive the guide mirror, correct the beam deflection caused by wavefront distortion, and adjust the coupling efficiency evaluation function in real time to maximize it, that is, determine the best position of the guide mirror.

According to the method described in step c and step d, the present invention can adjust the energy coupling efficiency evaluation function and the wavefront reconstruction matrix according to the value of the predicted wavefront and the previous received signal, and then make a judgment, and so on, until the optimal ; The entire novel adaptive optics process forms a closed-loop control on the system.

The novel adaptive optics system without wavefront sensor provided by the present invention mainly consists of an optical receiving aperture lens, a beam collimating lens, a first converging lens, a spatial light modulator, a collimating lens, a guide mirror, and a second converging lens Composed of photodetectors, they are sequentially connected with optical path signals.

The invention provides the above-mentioned novel adaptive optics system without a wavefront sensor, and its application in high-speed space optical communication or optical imaging.

The specific application process of the system of the present invention is as follows:

The first step, beam convergence and shaping:

The beam from the transmitter end of the free space optical transmission system is converged by the optical receiving aperture lens, and the beam is shaped by the beam collimating lens and the first converging lens outside the focal length of the optical receiving aperture lens, and the beam collimating lens will optically receive The beam of the aperture lens is converted into a parallel beam, and the first converging lens converges the light emitted from the beam collimating lens and sends it to the spatial light modulator;

In the second step, the optical signal is converted into an electrical signal:

The light beam emitted by the spatial light modulator is collimated by the collimator lens and then enters the guide mirror, and the light emitted by the guide mirror is converged by the second converging lens and then sent to the photodetector; the photodetector converts the optical signal into an electrical signal , as the reference data for establishing the coupling efficiency evaluation function; the coupling evaluation function is given by the computer through the receiving algorithm;

The third step is to form the reconstructed wavefront control signal:

The predicted wavefront and the coupling efficiency evaluation function are sent to the wavefront reconstruction algorithm processor together, and the reconstructed wavefront control signal is formed through the iterative operator, the steepest gradient descent algorithm and the genetic algorithm;

The fourth step is to output the driving signal:

The reconstructed wavefront control signal is divided into two channels and sent to the tilt compensation and the reconstructed wavefront compensation respectively, as the tilt compensation driving signal and the reconstructed wavefront device—the driving signal of the spatial light modulator.

Technical characteristics of the present invention are:

(1) Instead of using wavefront sensors, statistical prediction methods and autocorrelation interferometry techniques are used to obtain initial wavefronts,

(2) Implement wavefront distortion compensation at the focal plane.

(3) The wavefront distortion compensation control loop implements open-loop control.

(4) Small size, light weight, fast response speed, the response frequency can reach 5000Hz.

(5) The 128×128 unit sub-aperture wavefront reconstruction technology is adopted to implement high-precision wavefront distortion compensation.

(6) A fast algorithm for wavefront reconstruction using a recursive least square algorithm combined with a genetic algorithm.

(7) According to the preset energy maximum value (Strehl ratio), the energy coupling efficiency is determined according to the signal fed back by the photodetector, so while improving the energy coupling efficiency, the signal flicker caused by the wavefront distortion is eliminated effect.

Compared with the traditional adaptive optics technology, the present invention also has the following main advantages:

1. Comply with the characteristics of free space optical communication system.

Since there is no traditional wavefront sensor, and the wavefront open-loop control compensation is implemented at the focal plane, the algorithm is fast and simple, which makes the system compensation response fast, the volume is reduced, the weight is light, the cost is low, and it is convenient for large-scale integration. And this is exactly the characteristic that adaptive optics system pursues.

Second. Improve the reliability of the communication system.

It can effectively compensate the wavefront distortion generated by the light field propagating in the random medium, thereby eliminating the signal flicker caused by the wavefront distortion caused by the turbulent atmosphere, reducing the bit error rate of the communication system, and improving the reliability of the communication system.

Three. It is convenient for popularization and application.

The provided system also has the advantage of high precision, is not only suitable for high-speed optical communication in long-distance free space, but also suitable for optical imaging, and is convenient for popularization and application.

Fourth, strong practicability: it has significant advantages in the field of aerospace technology and space technology.

The technology of the present invention is applied to a 1.25Gbit/s free space optical communication system. When the transmission distance is 3 kilometers and the atmospheric visibility is 5 kilometers, the bit error rate of the communication system is 10 ^-6 when the AO system is not used; When using the AO technology of the present invention, the bit error rate drops to 10 ^-8 , and the system performance is improved by two orders of magnitude.

Description of drawings

FIG. 1 is a schematic structural diagram of a novel adaptive optics system without a wavefront sensor of the present invention.

In the figure: 1. Optical receiving aperture lens; 2. Beam collimating lens; 3. First converging lens; 4. Collimating lens; 5. Second converging lens; 6. Photodetector.

Detailed ways

The present invention will be further described below in conjunction with the embodiments and accompanying drawings.

Example 1. A Novel Adaptive Optics Approach Without a Wavefront Sensor

The method includes the following steps:

a. Use statistical predictive analysis methods to establish an initial wave front.

This is the key to the technology of the present invention. According to the characteristics of atmospheric turbulence, various turbulence models are statistically analyzed to establish an adaptively adjustable initial wave front as a reference wave front for correcting the distorted wave front. The method is to perform variational processing on the refractive index structure functions of various turbulence models, use the multi-layer turbulence atmospheric model, and then use the Zernik wave front model to statistically analyze the initial wave front in the circular domain.

The initial wavefront is used as the reference wavefront for wavefront correction. In the subsequent wavefront reconstruction genetic algorithm, adaptive adjustment will be carried out according to the following method: when comparing the current detection When the evaluation of the wavefront parameters does not reach the ideal state, according to the current evaluation parameters of the wavefront distortion obtained by the RLS algorithm and the genetic algorithm, the predicted initial wavefront parameters are adaptively adjusted, and the wavefront is statistically predicted and reconstructed again. , and then take the coupling efficiency and Strehl ratio as the evaluation factors to correct the wavefront distortion, and so on until the tolerance error is reached.

b. Construct the coupling efficiency evaluation function from the output signal of the photodetector.

The signal output by the photodetector is used as a reference for evaluating the strength of the received signal of the system, and also as a reference for evaluating the wavefront distortion correction. The method is to establish the coupling efficiency evaluation function of the received light energy of the communication system based on the relationship between the measured photodetector output signal and the detection output signal corresponding to the initial wavefront, using the Strehl ratio on the field in step a. As one of the reference data for real-time adjustment of wavefront reconstruction parameters.

c. In the wavefront reconstruction algorithm processor, the predicted wavefront and coupling efficiency evaluation function are processed by the wavefront reconstruction algorithm combining the RLS algorithm and the genetic algorithm, and the tilt compensation signal and the reconstructed wavefront matrix information are obtained.

The specific method is: the tilt compensation signal and the wavefront reconstruction matrix information are respectively based on the coupling efficiency evaluation function and the initial wavefront information. When the coupling efficiency is the highest, that is, the coupling efficiency function reaches the maximum value, it is determined that the tilt compensation is optimal; and After multiple iterations of the genetic algorithm, the algorithm confirms that the Strehl ratio reaches the maximum and the coupling efficiency function reaches the maximum value, the wavefront reconstruction matrix information is then determined.

d. Reconstruct the wavefront matrix into 128×128 units to control the amount of information, drive the spatial light modulator, and compensate the distorted wavefront; the tilt compensation signal drives the guide mirror, corrects the beam deflection caused by the turbulent atmosphere, and improves the energy coupling efficiency.

The specific method is: when the parameters of the 128×128 wavefront reconstruction matrix are determined, the information of each unit of the matrix is converted into a voltage drive signal, and the wavefront compensation device - the spatial light modulator is driven to correct the distorted wavefront, and the The corrected wavefront information is sent to the algorithm processing unit, and the judgment is repeated until the Strehl ratio reaches the maximum, at which point it is determined that the wavefront correction meets the requirements. The tilt compensation output signal obtained by the algorithm drives the guide mirror, corrects the beam deflection caused by wavefront distortion, and adjusts the coupling efficiency evaluation function in real time to maximize it, that is, to determine the best position of the guide mirror.

e. According to the energy coupling efficiency evaluation function, further judge and adjust the predicted wavefront, and reconstruct the wavefront matrix and tilt compensation signal through the control loop adjustment.

As described in step c and step d, the energy coupling efficiency evaluation function and wavefront reconstruction matrix are adjusted according to the value of the predicted wavefront and the previous received signal, and then judged, and so on until the best. The whole process forms a closed-loop control on the system.

Repeat the above process until the maximum energy coupling efficiency is obtained. The coupling efficiency is typically 90%.

After the above process is completed, while the maximum energy coupling efficiency is obtained, the optical signal entering the guide mirror from the spatial light modulator has been compensated for wavefront distortion. Therefore, the signal flicker due to wavefront distortion is also eliminated at the same time.

Example 2. Novel adaptive optics system without wavefront sensor

The structure of a new adaptive optics system without a wavefront sensor is shown in Figure 1: the system is mainly composed of an optical receiving aperture lens 1, a beam collimating lens 2, a first converging lens 3, a spatial light modulator, a collimating lens 4, The guide mirror, the second converging lens 5 and the photodetector 6 are composed, and they are sequentially connected with optical path signals.

The invention provides the above-mentioned novel adaptive optics system without a wavefront sensor, and its application in high-speed space optical communication or optical imaging.

The specific application process of the novel adaptive optics system without wavefront sensor of the present invention is as follows:

The first step, beam convergence and shaping:

The optical receiving aperture lens 1 of the receiver converges the light beam from the transmitter end of the free-space optical transmission system, and the beam is shaped outside the focal length of the optical receiving aperture lens 1 through the beam collimating lens 2 and the first converging lens 3, The beam collimating lens 2 transforms the beam of the optical receiving aperture lens 1 into a parallel beam, and the first converging lens 3 converges the light emitted from the beam collimating lens 2 and sends it to the spatial light modulator.

In the second step, the optical signal is converted into an electrical signal:

The light beam emitted by the spatial light modulator is collimated by the collimator lens 4 and enters the guide mirror, and the light emitted by the guide mirror is converged by the second converging lens 5 and sent to the photodetector 6 . The photodetector 6 converts the optical signal into an electrical signal as reference data for establishing a coupling efficiency evaluation function; the coupling evaluation function is given by a computer through a receiving algorithm.

The spatial light modulator is placed on the focal plane of the first converging lens 3 as a compensation device for the distorted wavefront, and its compensation process is determined by the reconstructed wavefront signal.

The guide mirror has two functions: one is used as a tilt compensation optical device to correct the low-order error of beam wavefront distortion; the other is used as a beam direction correction device to correct the beam propagation direction.

The third step is to form the reconstructed wavefront control signal:

The predicted wavefront and the coupling efficiency evaluation function are sent to the wavefront reconstruction algorithm processor together, and the reconstructed wavefront control signal is formed through the iterative operator, the steepest gradient descent algorithm and the genetic algorithm.

The fourth step is to output the drive signal:

The reconstructed wavefront control signal is divided into two channels and sent to the tilt compensation and the reconstructed wavefront compensation respectively, as the tilt compensation driving signal and the reconstructed wavefront device—the driving signal of the spatial light modulator.

The above is just an embodiment of the present invention, and the present invention is not limited to the above embodiment.

Claims (3)

1. A novel adaptive optics method without a wavefront sensor, characterized in that the method may further comprise the steps: a. Establish an initial wavefront: Using statistical predictive analysis methods, specifically: performing variational processing on the refractive index structure functions of various turbulence models, using multi-layer turbulent atmospheric models, and then using the Zernik wavefront model to statistically analyze and set the reference initial wavefront in the circular domain ; The initial wavefront is used as a reference wavefront for implementing wavefront correction, and will be adaptively adjusted in the subsequent wavefront reconstruction neural network genetic algorithm; The method of self-adaptive adjustment is: when the evaluation of the wavefront parameters currently detected according to the coupling efficiency evaluation function and the Strehl ratio does not reach the ideal state, then according to the current evaluation of the wavefront distortion obtained by the RLS algorithm and the genetic algorithm The parameters are adaptively adjusted to predict the initial wavefront parameters, and the wavefront is re-statistically predicted and reconstructed, and then the coupling efficiency and Strehl ratio are used as factors for evaluating and correcting the wavefront distortion, and so on until reaching error tolerance; b. Construct the coupling efficiency evaluation function: The coupling efficiency evaluation function is constructed from the signal output by the photodetector, specifically: according to the relationship between the measured photodetector output signal and the detection output signal corresponding to the initial wavefront, using the Strehl ratio on the circular domain in step a, Establish the coupling efficiency evaluation function of the received light energy of the communication system, as one of the reference data for real-time adjustment of the wavefront reconstruction parameters; c. Obtain tilt compensation signal and reconstructed wavefront matrix information: In the wavefront reconstruction algorithm processor, the predicted wavefront and the coupling efficiency evaluation function are processed by the wavefront reconstruction algorithm combined with the RLS algorithm and the genetic algorithm, and the tilt compensation signal and the reconstructed wavefront matrix information are obtained; The specific method is: the tilt compensation signal and the wavefront reconstruction matrix information are respectively based on the coupling efficiency evaluation function and the initial wavefront information. When the coupling efficiency is the highest, that is, the coupling efficiency function reaches the maximum value, it is determined that the tilt compensation is optimal; and After multiple iterations of the genetic algorithm, the algorithm confirms that the Strehl ratio reaches the maximum and the coupling efficiency function reaches the maximum value, the wavefront reconstruction matrix information is then determined; d. Determine the best position of the guide mirror: Reconstruct the wavefront matrix into 128×128 units to control the amount of information, drive the spatial light modulator, and implement compensation for the distorted wavefront; the tilt compensation signal drives the guide mirror to correct the beam deflection caused by the turbulent atmosphere, so as to improve the energy coupling efficiency ; The specific method is: when the parameters of the 128×128 wavefront reconstruction matrix are determined, the information of each unit of the matrix is converted into a voltage drive signal, and the wavefront compensation device--spatial light modulator is driven to correct the distorted wavefront, and the The corrected wavefront information is sent to the algorithm processing unit, and the judgment is repeated until the Strehl ratio is the largest. At this time, it is determined that the wavefront correction meets the requirements; and the tilt compensation output signal obtained by the algorithm drives the guide mirror to correct the wavefront. Beam deflection caused by front distortion, and adjust the coupling efficiency evaluation function in real time to make it reach the maximum, that is, to determine the best position of the guide mirror; e. According to the energy coupling efficiency evaluation function, further judge and adjust the predicted wavefront, and adjust and reconstruct the wavefront matrix and tilt compensation signal through the control loop; The above process is repeated until the maximum energy coupling efficiency is obtained, and the signal flicker caused by wavefront distortion is eliminated at the same time. the 2. The novel adaptive optics method according to claim 1, characterized in that the signal output by the photodetector in step b is used as a reference for evaluating the strength of the received signal of the system, and simultaneously as a reference for evaluating the wavefront distortion correction. 3. The novel adaptive optics method according to claim 1, characterized in that according to the method described in step c and step d, the energy coupling efficiency evaluation function and the wavefront reconstruction matrix are calculated according to the predicted wavefront and the previous received signal The value is adjusted, and then judged, and so on until it is optimal; the entire process of the novel adaptive optics forms a closed-loop control on the system. the

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