Unmanned aerial vehicle energy transmission system based on laser phased array and full-range aberration correction method

Abstract

This invention relates to the fields of laser wireless power transfer and adaptive optics, and particularly to a UAV power transfer system based on a laser phased array and a method for full-range aberration correction. The system includes a laser, a preamplifier, a beam splitter, multiple phase shifters, multiple main amplifiers, multiple adaptive fiber collimators, an imaging telescope system, an adaptive optics system, a programmable aberration plate, a beam splitter, a photodetector, and a controller. This invention models the phase noise of the transmitting units within the laser phased array and the atmospheric turbulence distortion in the laser transmission path as a unified "full-range aberration." Through an integrated correction strategy combining near-field aberration physical simulation and internal closed-loop optimization, it effectively overcomes the inherent defects of traditional in-loop methods, such as large beam round-trip transmission delay and reliance on target return signals. This improves the system's correction speed, robustness, and final spot quality and energy transfer efficiency on the UAV target surface when transferring energy to high-speed moving targets.

Description

Technical Field

[0001] This invention relates to the fields of laser wireless power transmission and adaptive optics technology, and particularly to a UAV power transmission system based on a laser phased array and a method for full-process aberration correction. Background Technology

[0002] Laser wireless power transfer technology offers immense potential for the "unlimited" endurance of drones. The core concept involves emitting a high-power laser beam from a ground or air platform to remotely illuminate photovoltaic cells on the drone's fuselage, directly converting light energy into electrical energy and thus providing continuous power to the drone, fundamentally overcoming the physical limitations of its battery capacity. Among various transmission schemes, laser phased arrays have attracted significant attention due to their unique beam control capabilities. As an electrically controlled transmission system without mechanically moving parts, it can achieve rapid, inertial-free beam direction control and flexible focus adjustment by precisely adjusting the beam phase of each transmitting unit in the array. This characteristic makes it particularly suitable for real-time tracking and precise laser energy delivery to high-speed, maneuvering drones, with broad application prospects in civilian fields such as logistics, industrial inspection, and emergency rescue. However, this technology faces a core challenge in its practical application: the phase noise (internal aberration) between the emitting units of the laser phased array and the wavefront distortion (external aberration) caused by atmospheric turbulence on the laser transmission path work together to form "full-path aberration", which leads to the dispersion of the energy transfer spot, a decrease in energy density, and affects the final energy transfer efficiency.

[0003] To solve the "full-range aberration" problem, the key lies in simultaneously addressing internal noise and external dynamic disturbances. While laser phased arrays can control the internal phase, they cannot sense or predict the instantaneous changes in external atmospheric turbulence. Therefore, an adaptive optics system is needed to measure and compensate for the effects of atmospheric turbulence in real time. Adaptive optics systems provide crucial external disturbance information by detecting wavefront distortion caused by atmospheric turbulence from the target direction in real time. However, traditional adaptive optics systems are typically used to correct the imaging optical path. How to effectively apply the acquired information to the pre-compensation of the high-power transmission optical path and work in conjunction with the internal aberration correction of the phased array is a key technical challenge in constructing a high-performance laser power transfer system.

[0004] Currently, common full-range aberration correction methods for this challenge mostly employ a "target-in-the-loop" control strategy. This strategy uses the backscattered light intensity from the UAV's rear as an evaluation function, and iteratively optimizes the phase distribution of the phased array to achieve aberration correction. However, this method has significant limitations: each iteration requires waiting for the beam to complete its round-trip propagation before acquiring a new feedback signal, resulting in a limited system response frequency and difficulty in adapting to the dynamic scenarios of UAV flight. Furthermore, the backscattered light intensity is easily affected by factors such as UAV attitude and surface reflection characteristics, causing signal fluctuations. When the backscattered light intensity is lower than the detector sensitivity, the algorithm may even fail to function. These defects severely impact the control bandwidth and robustness of the optimization algorithm.

[0005] Therefore, existing technologies for laser energy transmission to mobile drones still lack an effective means to integrate adaptive optics' external sensing capabilities with the internal control capabilities of laser phased arrays to achieve high-speed, robust aberration correction. To address these issues, this invention proposes a novel drone energy transfer system based on a laser phased array and a corresponding end-to-end aberration correction method. This aims to improve the system's transmission efficiency and stability in dynamic environments, providing key technological support for the rapidly growing commercial applications of drones in the context of the low-altitude economy. Market research institutions predict that the global drone wireless charging market will grow to $2.1 billion by 2033, with a compound annual growth rate exceeding 20%. This technology is expected to play a significant role in this rapidly growing market. Summary of the Invention

[0006] Therefore, it is necessary to provide a UAV power transfer system and a full-process aberration correction method that can effectively combine the advantages of adaptive optics and laser phased array to address the aforementioned technical problems. This invention introduces an adaptive optics system to acquire atmospheric turbulence information in real time, and integrates this information with the internal aberrations of the laser phased array in the near field of the transmitter for unified simulation and closed-loop optimization. This solves the technical shortcomings of traditional methods, such as reliance on unstable return signals and slow response speed.

[0007] To solve the above-mentioned technical problems, the present invention adopts the following technical solution:

[0008] The UAV power transmission system based on laser phased array includes a laser, a preamplifier, a beam splitter, multiple phase shifters, multiple main amplifiers, multiple adaptive fiber collimators, an imaging telescope system, an adaptive optics system, a programmable aberration plate, a beam splitter, a photodetector, and a controller.

[0009] Laser, used to generate seed laser;

[0010] A preamplifier is used to initially amplify the low-power seed light;

[0011] A beam splitter is used to split the seed laser into several beams;

[0012] Multiple phase shifters, corresponding to the number of sub-beams, are used to perform phase modulation on each sub-beam;

[0013] The main amplifier is used to perform final high-power amplification of the pre-amplified laser.

[0014] An adaptive fiber collimator is used to collimate and transmit a sub-beam that has undergone phase modulation and power amplification, and to modulate its tilt phase to change the direction of the beam.

[0015] An imaging telescope with an adaptive optics system is used to observe the UAV target, acquire and correct atmospheric turbulence wavefront distortion information from the target direction, and improve the imaging quality of the target.

[0016] A programmable aberration plate is used to load wavefront distortion information acquired by the adaptive optics system;

[0017] A beam splitter element, positioned near the emission path of the adaptive fiber collimator array, is used to split the incident emission beam into a main energy beam and a sampling beam, and guide the sampling beam to the programmable aberration plate. The beam splitter element can be configured to use either a high reflectivity configuration where most of the energy is reflected as the main energy beam and a small portion is transmitted as the sampling beam, or a high transmittance configuration where most of the energy is transmitted as the main energy beam and a small portion is reflected as the sampling beam.

[0018] A photodetector is used to receive the sampled beam modulated by the programmable aberration plate and generate performance indicators characterizing the quality of the far-field beam.

[0019] When the photodetector is a point detector, a pinhole aperture or an intensity gradient potential well filter is provided in front of its photosensitive front. Such devices can be used to spatially filter the sampling beam so that the point detector only receives the light signal of the corresponding far-field main lobe region and generates the performance index accordingly.

[0020] When the photodetector is an area array detector, its connected processing circuit or the controller is configured to extract the signal component corresponding to a specific far-field region from the full-field light intensity distribution signal acquired by the detector in order to calculate the performance index.

[0021] The controller is connected to the photodetector, the phase shifter, and the adaptive fiber collimator respectively, and is used to run a control algorithm according to the performance indicators to adjust the phase settings of the phase shifter and the adaptive fiber collimator;

[0022] The control algorithms include, but are not limited to, stochastic parallel gradient descent (SPGD), dithering, simulated annealing, deep learning, and reinforcement learning.

[0023] In a preferred embodiment of the UAV power transmission system based on laser phased array provided by the present invention, the laser, preamplifier, beam splitter, phase shifter, main amplifier, and adaptive fiber collimator are sequentially connected in optical path to form a transmission channel.

[0024] In a preferred embodiment of the UAV power transmission system based on laser phased array provided by the present invention, the optical path connection of the imaging telescope with adaptive optics system constitutes an observation channel.

[0025] As a preferred embodiment of the UAV power transmission system based on laser phased array provided by the present invention, the adaptive optics system is an adaptive optics system with a wavefront sensor, including at least a wavefront sensor, a wavefront controller, and a wavefront corrector; the wavefront control method includes the direct slope method and the mode method.

[0026] As a preferred embodiment of the UAV power transmission system based on laser phased array provided by the present invention, the adaptive optics system is a wavefront sensorless adaptive optics system, which includes at least a wavefront corrector, a wavefront controller, and an image sensor; the wavefront corrector is directly controlled by an optimization algorithm based on the target sharpness index obtained by the image sensor to optimize the imaging quality of the imaging telescope system.

[0027] As a preferred embodiment of the UAV power transfer system based on laser phased array provided by the present invention, it further includes a focusing lens disposed between the programmable aberration plate and the photodetector to focus the sampling beam onto the photodetector.

[0028] In a preferred embodiment of the UAV power transmission system based on laser phased array provided by the present invention, the plurality of main amplifiers are disposed on the optical path between each of the phase shifters and the adaptive fiber collimator.

[0029] A method for correcting aberrations throughout the entire image is as follows:

[0030] The imaging telescope with an adaptive optics system receives the reflected light from the UAV target itself, performs adaptive optics correction on the UAV target to obtain a clear image, and acquires wavefront phase distortion information of atmospheric turbulence. Among them, the adaptive optics system with a wavefront sensor directly acquires the wavefront phase distortion information of atmospheric turbulence from the wavefront sensor, while the adaptive optics system without a wavefront sensor acquires the wavefront phase distortion information based on the control voltage inversion.

[0031] Load wavefront phase distortion information into a programmable aberration plate;

[0032] The energy-carrying beam is emitted through an adaptive fiber collimator array. At the near-field transmitter, a beam splitter is used to guide part of the beam as a sampling beam to a programmable aberration plate. The aberrations inside the laser phased array and the wavefront phase distortion loaded by the programmable aberration plate can form an equivalent full-range aberration at the near-field transmitter.

[0033] A photodetector is used to receive a sampled beam carrying full-range aberrations and to generate performance metrics.

[0034] Based on performance indicators, the controller runs a control algorithm to dynamically adjust the piston phase of each phase shifter and the tilt phase of each adaptive fiber collimator, optimize performance indicators, and complete the correction of aberrations throughout the entire process.

[0035] As a preferred embodiment of the full-range aberration correction method provided by the present invention, the wavefront corrector includes a deformable mirror and a fast-reflecting mirror, wherein the fast-reflecting mirror is used to achieve line-of-sight stabilization control of the target.

[0036] The wavefront sensors include, but are not limited to, Hartmann-Shack wavefront sensors, curvature sensors, and pyramidal sensors.

[0037] It is clear without a doubt that the technical solution described above in this application can solve the technical problem that this application aims to address.

[0038] Meanwhile, through the above technical solutions, the present invention has at least the following beneficial effects:

[0039] 1. The UAV power transfer system and full-path aberration correction method based on laser phased array provided by this invention unifies the phase noise of the transmitting unit inside the laser phased array and the atmospheric turbulence distortion in the laser transmission path into a "full-path aberration". Through an integrated correction strategy that combines near-field aberration physical simulation and internal closed-loop optimization, it effectively overcomes the inherent defects of traditional target-in-the-loop methods, such as large beam round-trip transmission delay and dependence on target return signals. It significantly improves the correction speed, robustness, and final spot quality and energy transmission efficiency of the system when transmitting energy to high-speed moving targets.

[0040] 2. This method does not rely on the intensity of backscattered light returned from the moving target as a feedback signal, fundamentally overcoming the problems of weak, fluctuating, or even interrupted backlight signals caused by factors such as changes in target reflection characteristics, attitude disturbances, and atmospheric obstruction. By using a photodetector to stably collect the light signal after simulating aberrations within the system to generate performance indicators, the high stability and controllability of the feedback source are ensured, greatly improving the reliability and environmental adaptability of the correction process and the entire system under different operating conditions.

[0041] 3. This invention can dynamically and in parallel optimize the phase shifter and adaptive fiber collimator array of the laser phased array; this achieves precise control of the laser wavefront, ensuring that a high-power-density homogenized spot can still be formed on the UAV target surface after long-distance atmospheric turbulence transmission (the phase of the laser phased array can also be adjusted as needed to generate other shapes of spot), thereby significantly improving the final energy reception and conversion efficiency.

[0042] 4. This invention achieves a fundamental breakthrough over traditional separate correction (first correcting the aberration of the receiving optical path, or only optimizing the transmission phase) and iterative methods that rely on feedback from the target end. It creatively completes the simulation and pre-compensation of the transmission effect throughout the entire process inside the transmitter, providing a new and efficient technical path for solving the correction bandwidth and delay problems faced in laser wireless energy transmission to high-speed dynamic targets.

[0043] 5. Because the system of this invention does not rely on and process weak and unstable optical feedback signals from distant moving targets, it reduces the requirements for the reflectivity of the target surface and also reduces the dependence on high-sensitivity, complex anti-interference detection technologies. This simplifies the system's operating constraints, enhances its applicability in complex environments (such as those with dust, water vapor interference, or low target reflectivity), and lays the foundation for the application of laser wireless power transmission technology in a wider range of scenarios. Attached Figure Description

[0044] To more clearly illustrate the technical solutions of the embodiments of the present invention, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0045] Figure 1 This is a flowchart of the system of the present invention;

[0046] Figure 2 This is a schematic diagram of the adaptive optics system based on a wavefront sensor according to the present invention;

[0047] Figure 3 This is a schematic diagram of the adaptive optics system based on a wavefront-less sensor according to the present invention;

[0048] Figure 4 This is a schematic diagram of the architecture of the present invention;

[0049] Figure 5 This is a diagram showing the surface light spot morphology of a photovoltaic cell under open-loop and closed-loop conditions in the simulation experiment of this invention.

[0050] Figure 6 This is a graph showing the trend of light intensity PV value changes during the simulation experiment of this invention. Detailed Implementation

[0051] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the invention.

[0052] To enable those skilled in the art to better understand the present invention, the technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings.

[0053] It should be noted that, unless otherwise specified, the embodiments and features and technical solutions in the embodiments of the present invention can be combined with each other.

[0054] It should be noted that similar labels and letters in the following figures indicate similar items. Therefore, once an item is defined in one figure, it does not need to be further defined and explained in subsequent figures.

[0055] Example 1

[0056] Reference Figures 1-4 A laser phased array-based UAV power transfer system includes:

[0057] Includes lasers, preamplifiers, beam splitters, multiple phase shifters, multiple main amplifiers, multiple adaptive fiber collimators, imaging telescope systems, adaptive optics systems, programmable aberration plates, beam splitters, photodetectors, and controllers;

[0058] Laser, used to generate seed laser;

[0059] A preamplifier is used to initially amplify the low-power seed light;

[0060] A beam splitter is used to split a seed laser into several beams.

[0061] Multiple phase shifters, corresponding to the number of sub-beams, are used to modulate the phase of each sub-beam;

[0062] The main amplifier is used to perform final high-power amplification of the pre-amplified laser.

[0063] An adaptive fiber collimator is used to collimate and transmit a sub-beam that has undergone phase modulation and power amplification, and to modulate its tilt phase to change the direction of the beam.

[0064] In this embodiment, the adaptive fiber collimator array is part of the laser phased array and is used to adjust the tilt phase of the beam and control its direction. Furthermore, the adaptive fiber collimator requires a relatively high voltage to drive, which is amplified by a high-voltage amplifier.

[0065] Preferably, the laser, preamplifier, beam splitter, phase shifter, main amplifier, and adaptive fiber collimator are sequentially connected in optical path to form a transmission channel.

[0066] An imaging telescope with an adaptive optics system is used to observe UAV targets, acquire and correct atmospheric turbulence wavefront distortion information from the target direction, improve the imaging quality of the target, and thus achieve imaging of the entire UAV system through the telescope.

[0067] Preferably, the optical path connection of the imaging telescope with an adaptive optics system forms an observation channel.

[0068] Specifically, the adaptive optics system is a wavefront sensor-based adaptive optics system, which includes at least a wavefront sensor, a wavefront controller, and a wavefront corrector. Wavefront control methods include the direct slope method and the mode method. Its core is to compensate for aberrations introduced by atmospheric turbulence through a closed-loop control of "measurement-calculation-correction," thereby improving image quality.

[0069] Specifically, the adaptive optics system is a wavefront sensorless adaptive optics system, comprising at least a wavefront corrector, a wavefront controller, and an image sensor. An optimization algorithm directly controls the wavefront corrector based on the target sharpness index obtained from the image sensor, thereby optimizing the imaging quality of the imaging telescope system.

[0070] It also includes a target monitoring subsystem for identifying the location of the drone;

[0071] A programmable aberration plate is used to load wavefront distortion information acquired by an adaptive optics system.

[0072] Preferably, the programmable aberration plate is electrically connected to the adaptive optics system for loading the wavefront distortion information provided by it;

[0073] In this embodiment, the programmable aberration plate includes, but is not limited to, a transmissive spatial light modulator, a reflective spatial light modulator, a deformable mirror, etc.

[0074] A beam splitter element, positioned near the emission path of the adaptive fiber collimator array, is used to split the incident emission beam into a main energy beam and a sampling beam, and guide the sampling beam to the programmable aberration plate. The beam splitter element can be configured to use either a high reflectivity configuration where most of the energy is reflected as the main energy beam and a small portion is transmitted as the sampling beam, or a high transmittance configuration where most of the energy is transmitted as the main energy beam and a small portion is reflected as the sampling beam.

[0075] A photodetector is used to receive a sampled beam modulated by a programmable aberration plate and generate a performance index characterizing the quality of the far-field beam. When the photodetector is a point detector, a pinhole aperture or an intensity gradient potential well filter is disposed in front of its photosensitive front. Such devices can be used to spatially filter the sampled beam, allowing the point detector to receive only the light signal corresponding to the main lobe region of the far field, and generate the performance index accordingly. When the photodetector is an area array detector, its connected processing circuit or the controller is configured to extract the signal component corresponding to a specific region of the far field from the full-field light intensity distribution signal acquired by the detector to calculate the performance index.

[0076] In this embodiment, the selection of the photodetector must be closely matched with the system calibration strategy (such as the optimization algorithm used) and performance indicators. Its core function is to convert the sampled optical signal modulated by the programmable aberration plate into a high signal-to-noise ratio electrical signal, providing feedback for closed-loop optimization of the controller. A wide variety of device types can be selected, including but not limited to:

[0077] High-sensitivity point detectors, such as avalanche photodiodes, photodiodes, or photomultiplier tubes, are suitable for fast closed-loop control where the total intensity of the light spot or "power in the barrel" is used as the optimization index.

[0078] Area array imaging detectors: such as scientific-grade CCD cameras, CMOS cameras or high-speed cameras, are suitable for wavefront-free sensorless optimization algorithms that require the acquisition of the complete two-dimensional intensity distribution of the far-field light spot in order to calculate complex indicators such as the cross-correlation coefficient between the far-field light intensity distribution and the photovoltaic cell area, the Strell ratio, the surrounding energy, and the PV value of the light intensity.

[0079] Position / quadrant detectors: such as four-quadrant detectors or position-sensitive detectors, are suitable for applications that require rapid calculation of the spot centroid position, coarse beam tracking, or specific correction of tilt aberrations.

[0080] The specific selection depends on a comprehensive consideration of response bandwidth, sensitivity, dynamic range and spatial resolution. Ensuring accurate and real-time evaluation of the beam quality after "full-path aberration" modulation is the key to achieving efficient internal closed-loop optimization.

[0081] The controller is connected to the photodetector, phase shifter, and adaptive fiber collimator respectively, and is used to run a control algorithm to adjust the phase settings of the phase shifter and adaptive fiber collimator according to performance indicators.

[0082] Specifically, the control algorithm used by the controller is any one of the SPGD algorithm, the dithering method, or the artificial intelligence algorithm. Preferably, the control algorithm includes, but is not limited to, the SPGD algorithm, the single dithering method, the multi-dithering method, the simulated annealing algorithm, the deep learning algorithm, and the reinforcement learning algorithm.

[0083] It also includes a focusing lens, which is positioned between the programmable aberration plate and the photodetector to focus the sampling beam onto the photodetector;

[0084] It also includes multiple fiber amplifiers, which are placed in the optical path between each phase shifter and the adaptive fiber collimator.

[0085] Example 2

[0086] refer to Figure 4 Based on the above embodiment one, a full-range aberration correction method is disclosed, the steps of which are as follows:

[0087] The imaging telescope with an adaptive optics system receives the reflected light from the UAV target itself, performs adaptive optics correction on the UAV target to obtain a clear image, and acquires wavefront phase distortion information of atmospheric turbulence. Among them, the adaptive optics system with a wavefront sensor directly acquires the wavefront phase distortion information of atmospheric turbulence from the wavefront sensor, while the adaptive optics system without a wavefront sensor acquires the wavefront phase distortion information based on the control voltage inversion.

[0088] Load wavefront phase distortion information into a programmable aberration plate;

[0089] The energy-carrying beam is emitted through an adaptive fiber collimator array. At the near-field transmitter, a beam splitter is used to guide part of the beam as a sampling beam to a programmable aberration plate. The aberrations inside the laser phased array and the wavefront phase distortion loaded by the programmable aberration plate can form an equivalent full-range aberration at the near-field transmitter.

[0090] A photodetector is used to receive a sampled beam carrying full-range aberrations and generate performance indicators. The controller runs a control algorithm based on the performance indicators to dynamically adjust the piston phase of each phase shifter and the tilt phase of each adaptive fiber collimator, thereby optimizing the performance indicators, correcting full-range aberrations, and optimizing beam quality.

[0091] Figure 4 In spatial light modulators (SLMs), the incident beam should be beam-constricted so that all beams can be modulated. Control algorithms include, but are not limited to, SPGD, dithering, simulated annealing, deep learning, and reinforcement learning algorithms.

[0092] Wavefront correctors include deformable mirrors and fast-reflecting mirrors, with the fast-reflecting mirrors used to achieve line-of-sight stabilization control of the target; wavefront sensors include, but are not limited to, Hartmann-Shack wavefront sensors, curvature sensors, and pyramidal sensors.

[0093] Example 3

[0094] Based on the above embodiment one, a specific application case is disclosed:

[0095] The seed beam emitted from the laser is split into 37 paths by a beam splitter (the number of paths can be increased or decreased as needed). Each sub-beam is then amplified by a phase shifter and an fiber amplifier before being injected into a 37-element adaptive fiber collimator array. Most of the energy of the collimated beam emitted from this array is directed towards the UAV, with a small portion being separated by a beam splitter and entering the near-field correction optical path. In the near-field correction optical path, a single SLM (Synthetic Light Modulator) acts as a programmable aberration plate. The size of the beam array is scaled down to a size smaller than the SLM to ensure that the wavefront phase of all beams can be modulated by the SLM.

[0096] Imaging telescope systems (e.g., a Cassegrain system) integrate an adaptive optics system based on a Hartmann wavefront sensor to measure atmospheric turbulence information returning from UAV targets in real time and send the measured wavefront distortion to the SLM (Scanning Lens) by scaling. The near-field sampled beam, after passing through the SLM loaded with the distortion map, is focused onto an area array imaging detector by a lens. The far-field intensity PV value of this simulated far-field spot is calculated to evaluate the final spot homogenization effect; a smaller PV value is better.

[0097] The controller employs the SPGD algorithm, continuously adjusting the driving voltages of each phase shifter and each adaptive fiber collimator while observing changes in the light intensity PV value. It seeks the optimal voltage combination that minimizes the light intensity PV value, thereby simultaneously suppressing the effects of internal phased array noise and atmospheric turbulence. Experiments show that after correction using this system, the light intensity PV value can be reduced from approximately 5.9 to 1.1, significantly improving energy transfer efficiency.

[0098] Example 4

[0099] refer to Figures 5-6 Based on the above embodiments one to three, simulation experiments are disclosed.

[0100] Numerical evaluation was conducted on the far-field beam shaping performance of a hexagonal laser phased array under different atmospheric turbulence conditions.

[0101] The simulation used a wavelength λ=1064nm, a transmission distance z=2000m, a computational grid N=512×512, 37 sub-apertures, a sub-aperture diameter of 28mm, an adjacent aperture spacing of 31mm, and an atmospheric coherence length r0 of 5cm. The SPGD algorithm was used to adjust the phase correction aberrations of each element in the laser phased array, forming a uniform light spot on the photovoltaic target surface. The final effect was evaluated using the far-field light intensity PV value; a smaller PV value is better. It was found that using the method of this patent, the light intensity PV value could be reduced from 5.9 in the open-loop state to 1.1 in the closed-loop state.

[0102] The preferred embodiments of the present invention disclosed above are merely illustrative of the invention. These preferred embodiments do not exhaustively describe all details, nor do they limit the invention to the specific implementations described. Clearly, many modifications and variations can be made based on the content of this specification. This specification selects and specifically describes these embodiments to better explain the principles and practical applications of the invention, thereby enabling those skilled in the art to better understand and utilize the invention. The invention is limited only by the claims and their full scope and equivalents.

Claims

1. A UAV power transfer system based on a laser phased array, characterized in that, Includes lasers, preamplifiers, beam splitters, multiple phase shifters, multiple main amplifiers, multiple adaptive fiber collimators, imaging telescope systems, adaptive optics systems, programmable aberration plates, beam splitters, photodetectors, and controllers; Laser, used to generate seed laser; A preamplifier is used to initially amplify the low-power seed light; A beam splitter is used to split the seed laser into several beams; Multiple phase shifters, corresponding to the number of sub-beams, are used to perform phase modulation on each sub-beam; The main amplifier is used to perform final high-power amplification of the pre-amplified laser. An adaptive fiber collimator is used to collimate and transmit a sub-beam that has undergone phase modulation and power amplification, and to modulate its tilt phase to change the direction of the beam. An imaging telescope with an adaptive optics system is used to observe the UAV target, acquire and correct atmospheric turbulence wavefront distortion information from the target direction, and improve the imaging quality of the target. A programmable aberration plate is used to load wavefront distortion information acquired by the adaptive optics system; A beam splitter element, positioned near the emission path of the adaptive fiber collimator array, is used to split the incident emission beam into a main energy beam and a sampling beam, and guide the sampling beam to the programmable aberration plate. The beam splitter element can be configured to use either a high reflectivity configuration where most of the energy is reflected as the main energy beam and a small portion is transmitted as the sampling beam, or a high transmittance configuration where most of the energy is transmitted as the main energy beam and a small portion is reflected as the sampling beam. A photodetector is used to receive the sampled beam modulated by the programmable aberration plate and generate performance indicators characterizing the quality of the far-field beam. When the photodetector is a point detector, a pinhole aperture or light intensity gradient potential well filter is provided in front of its photosensitive front. The device can be used to perform spatial filtering on the sampling beam so that the point detector only receives the light signal of the corresponding far-field main lobe region and generates the performance index accordingly. When the photodetector is an area array detector, its connected processing circuit or the controller is configured to extract the signal component corresponding to a specific far-field region from the full-field light intensity distribution signal acquired by the detector in order to calculate the performance index. The controller is connected to the photodetector, the phase shifter, and the adaptive fiber collimator respectively, and is used to run a control algorithm according to the performance indicators to adjust the phase settings of the phase shifter and the adaptive fiber collimator; The control algorithms include, but are not limited to, stochastic parallel gradient descent, dithering, simulated annealing, deep learning, and reinforcement learning.

2. The UAV power transfer system based on a laser phased array according to claim 1, characterized in that, The laser, preamplifier, beam splitter, phase shifter, main amplifier, and adaptive fiber collimator are sequentially connected in optical path to form a transmission channel.

3. The UAV power transfer system based on a laser phased array according to claim 1, characterized in that, The optical path connection of the imaging telescope with adaptive optics system forms an observation channel.

4. The UAV power transfer system based on a laser phased array according to claim 1, characterized in that, The adaptive optics system is an adaptive optics system with a wavefront sensor, including at least a wavefront sensor, a wavefront controller, and a wavefront corrector; the wavefront control methods include the direct slope method and the mode method.

5. The UAV power transfer system based on a laser phased array according to claim 1, characterized in that, The adaptive optics system is a wavefront sensorless adaptive optics system, which includes at least a wavefront corrector, a wavefront controller, and an image sensor; the wavefront corrector is directly controlled by an optimization algorithm based on the target sharpness index obtained from the image sensor, thereby optimizing the imaging quality of the imaging telescope system.

6. The UAV power transfer system based on a laser phased array according to claim 1, characterized in that, It also includes a focusing lens, which is disposed between the programmable aberration plate and the photodetector to focus the sampling beam onto the photodetector.

7. The UAV power transfer system based on a laser phased array according to claim 1, characterized in that, The plurality of main amplifiers are disposed in the optical path between each of the phase shifters and the adaptive fiber collimator.

8. A method for full-range aberration correction, used in the UAV power transfer system based on a laser phased array as described in any one of claims 1-7, characterized in that, The steps are as follows: The imaging telescope with an adaptive optics system receives the reflected light from the UAV target itself, performs adaptive optics correction on the UAV target to obtain a clear image, and acquires wavefront phase distortion information of atmospheric turbulence. Among them, the adaptive optics system with a wavefront sensor directly acquires the wavefront phase distortion information of atmospheric turbulence from the wavefront sensor, while the adaptive optics system without a wavefront sensor acquires the wavefront phase distortion information based on the control voltage inversion. Load wavefront phase distortion information into a programmable aberration plate; The energy-carrying beam is emitted through an adaptive fiber collimator array. At the near-field transmitter, a beam splitter is used to guide part of the beam as a sampling beam to a programmable aberration plate. The aberrations inside the laser phased array and the wavefront phase distortion loaded by the programmable aberration plate can form an equivalent full-range aberration at the near-field transmitter. A photodetector is used to receive a sampled beam carrying full-range aberrations and to generate performance metrics. Based on performance indicators, the controller runs a control algorithm to dynamically adjust the piston phase of each phase shifter and the tilt phase of each adaptive fiber collimator, optimize performance indicators, and complete the correction of aberrations throughout the entire process.

9. The method for full-range aberration correction according to claim 8, characterized in that, The wavefront corrector includes a deformable mirror and a fast-reflecting mirror, the fast-reflecting mirror being used to achieve line-of-sight stabilization control of the target; The wavefront sensors include, but are not limited to, Hartmann-Shack wavefront sensors, curvature sensors, and pyramidal sensors.

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