Optical phased array wave beam processing method and optical phased array chip

Abstract

The invention provides an optical phased array wave beam processing method. The method comprises the steps that a laser light source is coupled into an optical phased array chip through a coupler; performing beam splitting processing on the laser light source output by the coupler by using an N-stage beam splitter to obtain 2N light beams; the 2N light beams are input into 2N phase shifters in a one-to-one correspondence mode, the working voltages of the 2N phase shifters are adjusted through a random parallel gradient descent algorithm, and the 2N light beams with the phases changed are obtained; and inputting the 2N light beams after phase change into 2N emission array elements in a one-to-one correspondence manner to obtain focused light beams. The invention further provides an optical phased array chip.

Description

Technical Field

[0001] The present disclosure relates to the technical field of optical beamforming, and in particular to an optical phased array beam processing method and an optical phased array chip. Background Art

[0002] In optical phased array (OPA) beamforming, the phase error needs to be effectively optimized to achieve the desired beam directivity and shape. The traditional Stochastic Parallel Gradient Descent (SPGD) algorithm is a widely used optimization method, but it has a slow convergence speed and is sensitive to environmental noise in specific applications. Therefore, it is crucial to develop a more efficient and robust SPGD algorithm. Summary of the invention

[0003] In order to solve the problems existing in the prior art, the embodiments of the present invention provide an optical phased array beam processing method and an optical phased array chip. The method utilizes an adaptive SPGD optimization algorithm to improve the efficiency and stability of phase optimization in OPA beamforming.

[0004] The first aspect of the present disclosure provides an optical phased array beam processing method, wherein the optical phased array chip includes a coupler, an N-level beam splitter, 2 N Phase shifters and 2 N There are transmitting array elements, N≥1, the method comprises: coupling a laser light source to an optical phased array chip through a coupler; performing beam splitting processing on the laser light source output by the coupler using an N-level beam splitter, and obtaining 2 N beam; N The beams are input one by one to 2 N phase shifters and use the stochastic parallel gradient descent algorithm to N The working voltages of the phase shifters are adjusted respectively to obtain the phase-changed 2 N A beam of light; the phase-changed 2 N The beams are input one by one to 2 N A transmitting array element is used to obtain a focused light beam.

[0005] Furthermore, the stochastic parallel gradient descent algorithm is used to N The working voltages of the phase shifters are adjusted respectively to obtain the phase-changed 2 N beam, including: initialization 2 NThe working voltage of the phase shifter and the parameters of the random parallel gradient descent algorithm are set, and the main lobe side mode suppression ratio is set as the fitness function of the random parallel gradient descent algorithm to obtain the initialized working voltage and the initialized algorithm parameters; the initialized working voltage and the initialized algorithm parameters are applied with positive and negative disturbances to obtain the adaptive results of the fitness function and the voltage gradient; the initialized algorithm parameters are adjusted according to the adaptive results of the fitness function, and the initialized working voltage is adjusted according to the voltage gradient; when the number of iterations of the random parallel gradient descent algorithm reaches the maximum number of iterations, or the value of the fitness function does not exceed the preset fitness function value within the preset number of iterations, the algorithm iteration is terminated, and the 2 after the phase change is output N A beam of light.

[0006] Furthermore, the parameters of the stochastic parallel gradient descent algorithm include learning rate, perturbation, optimal fitness and optimal solution; among them, initialization 2 N The operating voltage of the phase shifter and the parameters of the random parallel gradient descent algorithm include: N The working voltage of each phase shifter is initialized to obtain the initialized working voltage; the learning rate, disturbance, optimal fitness and optimal solution are initialized to obtain the initial values ​​of the learning rate, disturbance, optimal fitness and optimal solution respectively.

[0007] Furthermore, according to the adaptive results of the fitness function, the initialized algorithm parameters are adjusted, including: in the current iteration, if the value of the main lobe side mode suppression ratio is greater than the optimal value stored previously, the learning rate is adjusted according to the first preset ratio and the disturbance is adjusted according to the second preset ratio to obtain the optimal value of the current iteration.

[0008] Furthermore, adjusting the initialized algorithm parameters according to the adaptive result of the fitness function also includes: in the current iteration, if the value of the main lobe side mode suppression ratio is less than or equal to the optimal value stored previously, adjusting the learning rate according to the second preset ratio to obtain the optimal value of the current iteration.

[0009] The second aspect of the present disclosure provides an optical phased array chip, comprising: a coupler, used to couple a laser light source to obtain a coupled laser light source; an N-level beam splitter, electrically connected to the coupler, used to split the coupled laser light source to obtain two N beam; where N ≥ 1; 2 N phase shifter, electrically connected to the last beam splitter of the N-stage beam splitter in one-to-one correspondence, for N The phase of the beam is adjusted to obtain the phase-changed 2 N beam; among them, the random parallel gradient descent algorithm is used to 2 N The operating voltage of each phase shifter is adjusted to change the NThe phase of the beam; 2 N transmit array elements, and 2 N The phase shifters are electrically connected one by one to adjust the phase of the two N The beam is focused to obtain a focused beam.

[0010] Furthermore, a control module is included for electrically controlling the optical phased array chip.

[0011] Furthermore, the control module is also used to initialize 2 N The working voltage of the phase shifter and the parameters of the random parallel gradient descent algorithm are set, and the main lobe side mode suppression ratio is set as the fitness function of the random parallel gradient descent algorithm to obtain the initialized working voltage and the initialized algorithm parameters; the initialized working voltage and the initialized algorithm parameters are applied with positive and negative disturbances to obtain the adaptive results of the fitness function and the voltage gradient; the initialized algorithm parameters are adjusted according to the adaptive results of the fitness function, and the initialized working voltage is adjusted according to the voltage gradient; when the number of iterations of the random parallel gradient descent algorithm reaches the maximum number of iterations, or the value of the fitness function does not exceed the preset fitness function value within the preset number of iterations, the algorithm iteration is terminated, and the 2 after the phase change is output N A beam of light.

[0012] Furthermore, the parameters of the stochastic parallel gradient descent algorithm include learning rate, perturbation, optimal fitness and optimal solution; wherein the control module is also used to convert 2 N The working voltage of each phase shifter is initialized to obtain the initialized working voltage; the learning rate, disturbance, optimal fitness and optimal solution are initialized to obtain the initial values ​​of the learning rate, disturbance, optimal fitness and optimal solution respectively.

[0013] Furthermore, the control module is also used to adjust the learning rate according to the first preset ratio and adjust the disturbance according to the second preset ratio in the current iteration if the value of the main lobe side mode suppression ratio is greater than the optimal value stored previously, so as to obtain the optimal value of the current iteration.

[0014] A third aspect of the present disclosure provides an electronic device, comprising: the optical phased array chip provided by the second aspect of the present disclosure, wherein the chip is used to implement the optical phased array beam processing method provided by the first aspect of the present disclosure.

[0015] The present invention discloses an optical phased array beam processing method, which integrates an adaptive SPGD optimization algorithm in an optical phased array chip to optimize the beam processing of the optical phased array. NThe working voltage of each phase shifter is adjusted to achieve phase optimization in OPA beamforming. In addition, by adaptively adjusting the learning rate and perturbation size, the efficiency and stability of this method in the OPA beamforming process are improved, and the performance of the optical phased array chip in a noisy environment is improved. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] For a more complete understanding of the present disclosure and its advantages, reference will now be made to the following description taken in conjunction with the accompanying drawings, in which:

[0017] Figure 1 The flowchart of the optical phased array beam processing method according to an embodiment of the present disclosure is schematically shown;

[0018] Figure 2 The flowchart of light beam phase adjustment according to an embodiment of the present disclosure is schematically shown;

[0019] Figure 3 The schematic diagram shows the convergence of the traditional SPGD algorithm for optimizing a high-dimensional optimization problem with 100 dimensional variables;

[0020] Figure 4 The schematic diagram shows the convergence of the SPGD improved ADAM algorithm for optimizing a high-dimensional optimization problem with 100 dimensional variables;

[0021] Figure 5 A schematic diagram schematically shows the convergence of the improved SPGD algorithm according to an embodiment of the present disclosure for optimizing a high-dimensional optimization problem with 100 dimensional variables; and

[0022] Figure 6 The schematic diagram shows the structure of an optical phased array chip according to an embodiment of the present disclosure. DETAILED DESCRIPTION

[0023] Hereinafter, embodiments of the present disclosure will be described with reference to the accompanying drawings. However, it should be understood that these descriptions are exemplary only and are not intended to limit the scope of the present disclosure. In the following detailed description, for ease of explanation, many specific details are set forth to provide a comprehensive understanding of the embodiments of the present disclosure. However, it is apparent that one or more embodiments may also be implemented without these specific details. In addition, in the following description, descriptions of known structures and technologies are omitted to avoid unnecessary confusion of the concepts of the present disclosure.

[0024] The terms used herein are only for describing specific embodiments and are not intended to limit the present disclosure. The terms "comprise", "include", etc. used herein indicate the existence of the features, steps, operations and / or components, but do not exclude the existence or addition of one or more other features, steps, operations or components.

[0025] All terms (including technical and scientific terms) used herein have the meanings commonly understood by those skilled in the art, unless otherwise defined. It should be noted that the terms used herein should be interpreted as having a meaning consistent with the context of this specification, and should not be interpreted in an idealized or overly rigid manner.

[0026] In the case of using expressions such as "at least one of A, B, and C, etc.", it should generally be interpreted in accordance with the meaning of the expression generally understood by those skilled in the art (for example, "a system having at least one of A, B, and C" should include but is not limited to a system having A alone, B alone, C alone, A and B, A and C, B and C, and / or A, B, C, etc.). In the case of using expressions such as "at least one of A, B, or C, etc.", it should generally be interpreted in accordance with the meaning of the expression generally understood by those skilled in the art (for example, "a system having at least one of A, B, or C" should include but is not limited to a system having A alone, B alone, C alone, A and B, A and C, B and C, and / or A, B, C, etc.).

[0027] Some block diagrams and / or flow charts are shown in the accompanying drawings. It should be understood that some blocks or combinations thereof in the block diagrams and / or flow charts may be implemented by computer program instructions. These computer program instructions may be provided to a processor of a general-purpose computer, a special-purpose computer, or other programmable data processing device, so that these instructions, when executed by the processor, may create a device for implementing the functions / operations described in these block diagrams and / or flow charts. The technology disclosed herein may be implemented in the form of hardware and / or software (including firmware, microcode, etc.).

[0028] The technical solution of the present disclosure will be described in detail below in conjunction with the specific process of the optical phased array beam processing method in the specific embodiment of the present disclosure. It should be understood that the process and calculation structure of the optical phased array beam processing method shown in the accompanying drawings are only exemplary to help those skilled in the art understand the technical solution of the present disclosure, and are not intended to limit the scope of protection of the present disclosure.

[0029] Figure 1 The flowchart of the optical phased array beam processing method is schematically shown.

[0030] like Figure 1 As shown, the optical phased array beam processing method includes: steps S1 to S4.

[0031] In operation S1 , a laser light source is coupled to an optical phased array chip through a coupler.

[0032] In the embodiment of the present disclosure, the laser light source may be a light source with a wavelength ranging from visible light to infrared light. The laser light source is input into the coupler through an optical fiber.

[0033] In the disclosed embodiment, the optical phased array chip coupler, the N-stage beam splitter, 2 N Phase shifters and 2 N Transmitting array elements. N≥1.

[0034] For example, the N-stage beam splitters are respectively a first-stage beam splitter, a second-stage beam splitter, ..., an N-th-stage beam splitter.

[0035] For example, when N=3, the last beam splitter of the N-stage beam splitters (ie, the third-stage beam splitter) includes 8 beam splitters for splitting the light beam into 8 light beams. At this time, the number of corresponding phase shifters and transmitting array elements is also 8.

[0036] For example, each beam splitter in the Nth stage of beam splitters is electrically connected to a phase shifter in a one-to-one correspondence, and each phase shifter is electrically connected to each transmitting array element in a one-to-one correspondence.

[0037] In the embodiment of the present disclosure, the coupler may be a grating coupler or the like.

[0038] In operation S2, the laser light source output from the coupler is split by using an N-stage beam splitter to obtain 2 N A beam of light.

[0039] In the embodiment of the present disclosure, the laser light source after the grating coupler output coupling is subjected to beam splitting processing by an N-level beam splitter to obtain 2 N A beam of light.

[0040] For example, 2 N The light beams may be light beams of the same power.

[0041] In operation S3, 2 N The beams are input one by one to 2 N phase shifters and use the stochastic parallel gradient descent algorithm to N The working voltages of the phase shifters are adjusted respectively to obtain the phase-changed 2 N A beam of light.

[0042] In the embodiment of the present disclosure, a random parallel gradient descent algorithm is used to N The operating voltage of each phase shifter is adjusted to change the N The phase of each beam in the beam is adjusted to adjust the phase of each transmitting array element to optimize the side mode suppression ratio of the preset angle main lobe to achieve beam focusing.

[0043] In operation S4, the phase-changed 2 NThe beams are input one by one to 2 N A transmitting array element is used to obtain a focused light beam.

[0044] In the disclosed embodiment, the operating voltage of each phase shifter is adjusted multiple times by a random parallel gradient descent algorithm to change the phase of each transmitting array element to achieve a focused beam of optimal quality.

[0045] According to an embodiment of the present disclosure, an adaptive SPGD optimization algorithm is integrated into an optical phased array chip to optimize the optical phased array chip. N The working voltage of each phase shifter is adjusted to achieve phase optimization in OPA beamforming. In addition, by adaptively adjusting the learning rate and perturbation size, the efficiency and stability of this method in the OPA beamforming process are significantly improved to enhance the performance of the optical phased array chip in a noisy environment.

[0046] Specifically, Figure 2 As shown, S3 uses the random parallel gradient descent algorithm to 2 N The working voltages of the phase shifters are adjusted respectively to obtain the phase-changed 2 N The method of forming a light beam specifically includes steps S31 to S34.

[0047] In operation S31, initialization 2 N The operating voltage of the phase shifter and the parameters of the random parallel gradient descent algorithm are obtained, and the main lobe side mode suppression ratio is set as the fitness function of the random parallel gradient descent algorithm to obtain the initialized operating voltage and the initialized algorithm parameters.

[0048] In the embodiment of the present disclosure, the operating voltage of each phase shifter may be a random variable, which is a solution vector of the random parallel gradient descent algorithm, and is set to x.

[0049] For example, the operating voltage x of each phase shifter may be within a certain initial value range.

[0050] For example, if the operating voltage of each phase shifter is 0-10V, x can be set to 2V-8V or other value ranges. It should be noted that the value range of x can be adjusted according to actual conditions, and the embodiments of the present disclosure do not limit this.

[0051] In the embodiment of the present disclosure, the parameters of the stochastic parallel gradient descent algorithm include a learning rate (Alpha), a perturbation (Delta), an optimal fitness (F_best), and an optimal solution (x_best).

[0052] For example, the initial value of Alpha can be 0.1. The initial value of Delta can be 0.5.

[0053] For example, when the algorithm starts iterating, the initial value of x is set as the value of x_best to start iterating.

[0054] In the embodiment of the present disclosure, the fitness function satisfies the following relationship:

[0055]

[0056] Where E(θ) represents the light field distribution in the far field of the OPA. i represents the position of each transmitting array element, and d i represents the spacing between each transmitting array element, which is a constant. θ represents the extreme scanning angle of the optical phased array chip, which takes values ​​of [-90°, 90°]. f(θ) represents the array factor of the transmitting array element, in, α represents the width of a single transmitting element. λ represents the operating wavelength. θ s Indicates the scanning angle of the set main lobe, which is usually set to 0°.

[0057] In the embodiment of the present disclosure, the fitness function SMSR can be finally expressed as:

[0058]

[0059] Among them, I(θ)=E(θ)×conj(E(θ)), I(θ) represents the light intensity distribution in the far field of OPA.

[0060] It should be noted that the values ​​of the above parameters are only exemplary descriptions and do not constitute limitations of the present disclosure.

[0061] In operation S32, positive and negative disturbances are applied to the initialized working voltage and the initialized algorithm parameters to obtain an adaptive result of the fitness function and a voltage gradient.

[0062] In the embodiment of the present disclosure, in each iteration process, an adaptive result of the fitness function is generated; a disturbance delta_x is generated, and a voltage gradient (gradient_approximation) is calculated.

[0063] For example, the adaptive result of the fitness function includes generating the value of the fitness function (ie, the value of the main lobe side mode suppression ratio). The value of the fitness function in the current iteration is compared with the value of the fitness function in the previous iteration to adjust the algorithm parameters.

[0064] For example, the voltage gradient is an approximation of the voltage gradient to adjust the working voltage of the phase shifter in the subsequent iteration process. In the embodiment of the present disclosure, the voltage gradient can be approximately calculated using a symmetric difference method.

[0065] In the embodiment of the present disclosure, the solution vector x and the voltage gradient approximation gradient_approximation satisfy the following relationship:

[0066] x′=x-alpha×gradient_approximation

[0067] Where x' represents the solution vector in the current iteration, and x represents the solution vector in the previous iteration.

[0068] In operation S33, the initialized algorithm parameters are adjusted according to the adaptive result of the fitness function, and the initialized working voltage is adjusted according to the voltage gradient.

[0069] In the disclosed embodiment, in the current iteration, if the value of the main lobe side mode suppression ratio is greater than the previously stored optimal value, the learning rate is adjusted according to the first preset ratio and the disturbance is adjusted according to the second preset ratio to obtain the optimal value of the current iteration. Conversely, in the current iteration, if the value of the main lobe side mode suppression ratio is less than or equal to the previously stored optimal value, the learning rate is adjusted according to the second preset ratio to obtain the optimal value of the current iteration.

[0070] For example, the first preset ratio may be 1.05, and the second preset ratio may be 0.95.

[0071] For example, in the current iteration, the process of adjusting the learning rate is to multiply the value of the learning rate in the previous iteration by the first preset ratio or the second preset ratio to change the value of the learning rate in the current iteration.

[0072] For example, in the current iteration, after adjusting the operating voltage and algorithm parameters of each phase shifter, determine whether the current iteration number reaches the maximum iteration number, or whether the value of the fitness function exceeds the preset fitness function value within the preset iteration number. If the current iteration number does not reach the maximum iteration number, and the value of the fitness function does not exceed the preset fitness function value within the preset iteration number, repeat steps S32 to S33 to perform subsequent iterations to optimize the beam phase.

[0073] In operation S34, when the number of iterations of the random parallel gradient descent algorithm reaches the maximum number of iterations, or the value of the fitness function does not exceed the preset fitness function value within the preset number of iterations, the algorithm iteration is terminated, and the 2 after the phase change is output. N A beam of light.

[0074] In the embodiment of the present disclosure, the maximum number of iterations may be 50, 100, 200 or other values. The maximum number of iterations may be set according to the optical phased array chip and the array scale, and the embodiment of the present disclosure does not limit this.

[0075] For example, if the value of the fitness function does not exceed the preset fitness function value within 10 iterations, the algorithm iteration ends and the output is the 2 N At this time, the global optimal value is recorded and the corresponding voltage value is stored in the Look Up Table (LUT). If multi-angle beamforming is required, just change the selected angle and area and repeat the above operation.

[0076] Figure 3 to Figure 5 The convergence diagrams of the traditional SPGD algorithm, the ADAM improved SPGD algorithm and the improved SPGD algorithm provided in the embodiments of the present disclosure for optimizing the same high-dimensional optimization problem with 100 dimensional variables are respectively illustrated.

[0077] It can be understood that the side mode suppression ratio is an operation performed by taking the logarithm of the ratio of the main lobe to the maximum side lobe, and the larger the value, the better. Determining whether the fitness function has been improved is based on whether the value of the side mode suppression ratio in the current iteration process is greater than the value of the side mode suppression ratio in the previous iteration process. If the value of the side mode suppression ratio in the current iteration process is less than or equal to the value of the side mode suppression ratio in the previous iteration process, the fitness function has not been improved.

[0078] like Figure 3 As shown in the figure, the SPGD algorithm is relatively stable in the early convergence process, but due to the shrinking of the solution space in the later stage, the learning rate and disturbance are not adjusted in time, so jitter occurs and it cannot converge normally. Figure 4 As shown in the figure, although the SPGD ADAM improved algorithm stabilizes the convergence in the later stage because the learning rate gradually decreases with the increase of the number of iterations, it still has jitter and instability due to the fixed learning rate correction mode. Figure 5 As shown, the improved SPGD algorithm proposed in the embodiment of the present disclosure adjusts the learning rate and disturbance in real time according to the actual optimization situation, takes into account both the convergence speed and the algorithm stability, and is significantly better than the SPGD algorithm and the SPGD's ADAM improved algorithm in terms of convergence performance.

[0079] An embodiment of the present disclosure provides an optical phased array beam processing method, which can effectively improve the optimization efficiency and performance of phase adjustment in the application of OPA beamforming.

[0080] Figure 6 The schematic diagram shows the structure of an optical phased array chip according to an embodiment of the present disclosure.

[0081] like Figure 6 As shown, the optical phased array chip 600 includes: a coupler 610, an N-stage beam splitter 620, N phase shifter 630 and 2 NThe optical phased array chip 600 can be used to implement reference Figure 1 An optical phased array beam processing method is described.

[0082] The coupler 610 is used to couple the laser light source to obtain a coupled laser light source. The coupler 610 can be used to perform the above reference Figure 1 The S1 step described is not repeated here.

[0083] The N-stage beam splitter 620 is electrically connected to the coupler 610 and is used to perform beam splitting processing on the coupled laser light source to obtain 2 N Wherein, N≥1. The N-stage beam splitter 620 can be used to perform the above reference Figure 1 The described S2 step will not be repeated here.

[0084] 2 N The phase shifter 630 is electrically connected to the last beam splitter of the N-stage beam splitter in a one-to-one correspondence, and is used to N The phase of the beam is adjusted to obtain the phase-changed 2 N Among them, the random parallel gradient descent algorithm is used to N The operating voltage of each phase shifter is adjusted to change the N The phase of the beam. N The phase shifter 630 can be used to perform the above reference Figure 1 The S3 step described is not repeated here.

[0085] 2 N The transmitting array element 640 and 2 N The phase shifters are electrically connected one by one to change the phase of the 2 N The beam is focused to obtain a focused beam. N The transmit array element 640 may be used to perform the above-referenced Figure 1 The described S4 step will not be repeated here.

[0086] According to an embodiment of the present disclosure, the optical phased array chip 600 further includes a control module for electrically controlling the optical phased array chip.

[0087] According to an embodiment of the present disclosure, the control module is also used to initialize 2 NThe working voltage of the phase shifter and the parameters of the random parallel gradient descent algorithm are set, and the main lobe side mode suppression ratio is set as the fitness function of the random parallel gradient descent algorithm to obtain the initialized working voltage and the initialized algorithm parameters; the initialized working voltage and the initialized algorithm parameters are applied with positive and negative disturbances to obtain the adaptive results of the fitness function and the voltage gradient; the initialized algorithm parameters are adjusted according to the adaptive results of the fitness function, and the initialized working voltage is adjusted according to the voltage gradient; when the number of iterations of the random parallel gradient descent algorithm reaches the maximum number of iterations, or the value of the fitness function does not exceed the preset fitness function value within the preset number of iterations, the algorithm iteration is terminated, and the 2 after the phase change is output N A beam of light.

[0088] According to an embodiment of the present disclosure, the parameters of the stochastic parallel gradient descent algorithm include a learning rate, a perturbation, an optimal fitness, and an optimal solution; wherein the control module is also used to convert 2 N The working voltage of each phase shifter is initialized to obtain the initialized working voltage; the learning rate, disturbance, optimal fitness and optimal solution are initialized to obtain the initial values ​​of the learning rate, disturbance, optimal fitness and optimal solution respectively.

[0089] According to an embodiment of the present disclosure, the control module is also used to adjust the learning rate according to the first preset ratio and adjust the disturbance according to the second preset ratio in the current iteration if the value of the main lobe side mode suppression ratio is greater than the optimal value stored previously, so as to obtain the optimal value of the current iteration.

[0090] An embodiment of the present disclosure further provides an electronic device, comprising: the optical phased array chip provided in the second aspect of the present disclosure, wherein the chip is used to implement the optical phased array beam processing method provided in the first aspect of the present disclosure.

[0091] For example, the electronic device may be a vehicle-mounted device for measuring vehicle distance and vehicle speed, etc.

[0092] It should be noted that the functional modules in the various embodiments of the present disclosure may be integrated into a processing module, or each module may exist physically separately, or two or more modules may be integrated into one module. The above-mentioned integrated modules may be implemented in the form of hardware or in the form of software functional modules. If the integrated modules are implemented in the form of software functional modules and sold or used as independent products, they may be stored in a computer-readable storage medium. Based on such an understanding, the technical solution of the present disclosure may essentially or in other words, the part that contributes to the prior art or all or part of the technical solution may be embodied in the form of a software product.

[0093] The flow charts and block diagrams in the accompanying drawings illustrate the possible architecture, functions and operations of the devices, methods and computer program products according to various embodiments of the present disclosure. In this regard, each box in the flow chart or block diagram can represent a module, a program segment, or a part of a code, and the above-mentioned module, program segment, or a part of the code contains one or more executable instructions for realizing the specified logical function. It should also be noted that in some alternative implementations, the functions marked in the box can also occur in a different order from the order marked in the accompanying drawings. For example, two boxes represented in succession can actually be executed substantially in parallel, and they can sometimes be executed in the opposite order, depending on the functions involved. It should also be noted that each box in the block diagram or flow chart, and the combination of boxes in the block diagram or flow chart, can be implemented with a dedicated hardware-based device that performs a specified function or operation, or can be implemented with a combination of dedicated hardware and computer instructions.

[0094] It will be appreciated by those skilled in the art that the features described in the various embodiments and / or claims of the present disclosure may be combined and / or combined in a variety of ways, even if such combinations and / or combinations are not explicitly described in the present disclosure. In particular, the features described in the various embodiments and / or claims of the present disclosure may be combined and / or combined in a variety of ways without departing from the spirit and teachings of the present disclosure. All of these combinations and / or combinations fall within the scope of the present disclosure.

[0095] Although the present disclosure has been shown and described with reference to specific exemplary embodiments of the present disclosure, it should be understood by those skilled in the art that various changes in form and details may be made to the present disclosure without departing from the spirit and scope of the present disclosure as defined by the appended claims and their equivalents. Therefore, the scope of the present disclosure should not be limited to the above-mentioned embodiments, but should be determined not only by the appended claims, but also by the equivalents of the appended claims.

Claims

1. An optical phased array beam processing method, It is characterized in that The optical phased array chip includes a coupler, an N-level beam splitter, 2 N Phase shifters and 2 N There are transmitting array elements, N≥1, and the method comprises: Coupling the laser light source into the optical phased array chip through a coupler; The laser light source output by the coupler is split by using the N-stage beam splitter to obtain 2 N beam of light; The 2 N The beams are input one by one to the 2 N phase shifter, and use the stochastic parallel gradient descent algorithm to N The working voltages of the phase shifters are adjusted respectively to obtain the phase-changed 2 N beam of light; The phase-changed 2 N The beams are input one by one to the 2 N A transmitting array element is used to obtain a focused light beam.

2. The optical phased array beam processing method according to claim 1, It is characterized in that The random parallel gradient descent algorithm is used to N The working voltages of the phase shifters are adjusted respectively to obtain the phase-changed 2 N beam, including: Initialize the 2 N The operating voltage of the phase shifter and the parameters of the random parallel gradient descent algorithm are set, and the main lobe side mode suppression ratio is set as the fitness function of the random parallel gradient descent algorithm to obtain the initialized operating voltage and the initialized algorithm parameters; Applying positive and negative disturbances to the initialized working voltage and the initialized algorithm parameters to obtain the adaptive result of the fitness function and the voltage gradient; According to the adaptive result of the fitness function, adjusting the initialized algorithm parameters, and according to the voltage gradient, adjusting the initialized working voltage; When the number of iterations of the random parallel gradient descent algorithm reaches the maximum number of iterations, or the value of the fitness function does not exceed the preset fitness function value within the preset number of iterations, the algorithm iteration is terminated, and the 2 after the phase change is output. N A beam of light.

3. The optical phased array beam processing method according to claim 2, It is characterized in that The parameters of the random parallel gradient descent algorithm include learning rate, perturbation, optimal fitness and optimal solution; wherein, the initialization of the 2 N The operating voltage of the phase shifter and the parameters of the stochastic parallel gradient descent algorithm include: The 2 N Initialize the working voltage of each phase shifter to obtain the initialized working voltage; Initializing the learning rate, the disturbance, the optimal fitness and the optimal solution to obtain initial values ​​of the learning rate, the disturbance, the optimal fitness and the optimal solution respectively.

4. The optical phased array beam processing method according to claim 3, It is characterized in that The step of adjusting the initialized algorithm parameters according to the adaptive result of the fitness function comprises: In the current iteration, if the value of the main lobe side mode suppression ratio is greater than the previously stored optimal value, the learning rate is adjusted according to the first preset ratio and the disturbance is adjusted according to the second preset ratio to obtain the optimal value of the current iteration.

5. The optical phased array beam processing method according to claim 3, It is characterized in that The step of adjusting the initialized algorithm parameters according to the adaptive result of the fitness function further includes: In the current iteration, if the value of the main lobe side mode suppression ratio is less than or equal to the previously stored optimal value, the learning rate is adjusted according to the second preset ratio to obtain the optimal value of the current iteration.

6. An optical phased array chip, It is characterized in that include: A coupler is used to couple the laser light source to obtain a coupled laser light source; N-stage beam splitters are electrically connected to the coupler and are used to perform beam splitting processing on the coupled laser light source to obtain 2 N beams; where N ≥ 1; 2 N phase shifter, electrically connected to the last beam splitter of the N-stage beam splitter in one-to-one correspondence, for N The phase of the beam is adjusted to obtain the phase-changed 2 N wherein the 2 N The operating voltages of the two phase shifters are adjusted separately to change the N The phase of the beam; 2 N transmitting array elements, and the 2 N The phase shifters are electrically connected one by one to change the phase of the two N The beam is focused to obtain a focused beam.

7. The optical phased array chip according to claim 6, It is characterized in that Also includes: A control module is used to electrically control the optical phased array chip.

8. The optical phased array chip according to claim 7, It is characterized in that The control module is also used for: Initialize the 2 N The operating voltage of the phase shifter and the parameters of the random parallel gradient descent algorithm are set, and the main lobe side mode suppression ratio is set as the fitness function of the random parallel gradient descent algorithm to obtain the initialized operating voltage and the initialized algorithm parameters; Applying positive and negative disturbances to the initialized working voltage and the initialized algorithm parameters to obtain the adaptive result of the fitness function and the voltage gradient; According to the adaptive result of the fitness function, adjusting the initialized algorithm parameters, and according to the voltage gradient, adjusting the initialized working voltage; When the number of iterations of the random parallel gradient descent algorithm reaches the maximum number of iterations, or the value of the fitness function does not exceed the preset fitness function value within the preset number of iterations, the algorithm iteration is terminated, and the 2 after the phase change is output. N A beam of light.

9. The optical phased array chip according to claim 8, It is characterized in that The parameters of the stochastic parallel gradient descent algorithm include learning rate, perturbation, optimal fitness and optimal solution; wherein the control module is also used for: The 2 N Initialize the working voltage of each phase shifter to obtain the initialized working voltage; Initializing the learning rate, the disturbance, the optimal fitness and the optimal solution to obtain initial values ​​of the learning rate, the disturbance, the optimal fitness and the optimal solution respectively.

10. The optical phased array chip according to claim 9, It is characterized in that The control module is also used for: In the current iteration, if the value of the main lobe side mode suppression ratio is greater than the previously stored optimal value, the learning rate is adjusted according to the first preset ratio and the disturbance is adjusted according to the second preset ratio to obtain the optimal value of the current iteration.

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