Spatial domain linear phase modulation and energy efficiency optimization method, system, device and medium

Abstract

The application belongs to the technical field of electromagnetic beam regulation and artificial electromagnetic device, and discloses a spatial domain linear phase modulation and energy efficiency optimization method, system, device and medium, the method comprises the following steps: under the premise of not changing the original generation system structure and limited aperture radius, obtaining an output transverse plane complex amplitude distribution; loading a spatial domain linear phase modulation with a linear relationship with a radial coordinate to the complex amplitude distribution to obtain a modulated complex amplitude distribution; determining the modulated angular spectrum ring radius, equivalent wave vector angle and maximum non-diffraction distance according to the modulated complex amplitude distribution; and selecting a pre-reconstruction factor according to the distance to perform pre-reconstruction processing on the initial input plane field to compensate for the spatial energy efficiency decline caused by the phase modulation. The application effectively improves the non-diffraction distance under the limited aperture, and optimizes the energy efficiency through pre-reconstruction, and is suitable for long-distance free space communication and wireless energy transmission.

Description

Technical Field

[0001] This invention relates to the field of electromagnetic beam modulation and artificial electromagnetic devices, and in particular to a spatial domain linear phase modulation and energy efficiency optimization method, system, device and medium. Background Technology

[0002] In applications such as long-distance free-space communication, long-distance energy transmission, and directional illumination, it is desirable for electromagnetic beams to maintain a high energy concentration and stable spatial distribution over a long propagation distance in order to reduce energy loss caused by propagation and diffusion.

[0003] Zero-order Bessel electromagnetic beams possess concentrated energy in their central main lobe and exhibit near-diffraction-free propagation characteristics under ideal conditions. However, in engineering implementation, limited by finite aperture, the diffraction-free distance of zero-order Bessel electromagnetic beams has an upper limit, which is closely related to parameters such as the wave vector angle. To extend the diffraction-free distance, it is usually necessary to reduce the wave vector angle, but in existing zero-order Bessel beam generation systems, the wave vector angle is often difficult to reduce further, thus limiting the potential for increasing the diffraction-free distance.

[0004] Therefore, how to directly control the complex amplitude distribution of the output transverse plane to improve the non-diffraction distance without changing the original zero-order Bessel electromagnetic beam generation system structure and finite aperture radius, while simultaneously taking into account the compensation and optimization of spatial energy efficiency, is a technical problem that urgently needs to be solved in this field. Summary of the Invention

[0005] To address the aforementioned problems, this invention provides a spatial domain linear phase modulation and energy efficiency optimization method, system, device, and medium. While maintaining the existing zero-order Bessel electromagnetic beam generation system structure and finite aperture conditions, it directly applies spatial domain linear phase modulation to the output transverse plane complex amplitude distribution, through a modulation factor... This reduces the angular spectral ring and the equivalent wave vector angle, thereby increasing the maximum non-diffraction distance. Furthermore, pre-reconstruction processing is used to compensate for the decrease in spatial energy efficiency.

[0006] According to a first technical solution of the present invention, a spatial domain linear phase modulation and energy efficiency optimization method is provided, the method comprising: While keeping the existing zero-order Bessel electromagnetic beam generation system structure and finite aperture radius unchanged, obtain the complex amplitude distribution on the output transverse plane of the zero-order Bessel electromagnetic beam generation system; The complex amplitude distribution is subjected to spatial domain linear phase modulation that is linearly related to the transverse and radial coordinates to obtain the modulated complex amplitude distribution. Based on the spatial domain linear phase modulation, while keeping the finite aperture radius unchanged, the modulated angular spectral ring radius, equivalent wave vector angle, and maximum non-diffraction distance are determined. The pre-reconstruction factor is selected based on the maximum non-diffraction distance, and the initial input plane field of the zero-order Bessel electromagnetic beam generation system is pre-reconstructed to obtain the pre-reconstructed initial plane field distribution.

[0007] Furthermore, the modulated complex amplitude distribution is obtained using the following formula: in, The complex amplitude distribution before modulation. This represents the modulated complex amplitude distribution. For modulation factor, The horizontal and radial coordinates are... The imaginary unit, is the base of the natural logarithm.

[0008] Furthermore, the radius of the modulated angular spectral ring is obtained using the following formula: in, The radius of the modulated angular spectral ring. The radius of the angular spectral ring before modulation.

[0009] Furthermore, the modulated equivalent wave vector angle is obtained using the following formula: in, The equivalent wave vector angle after modulation. The equivalent wave vector angle before modulation. λ is the wavelength.

[0010] Furthermore, the maximum non-diffraction distance after modulation is obtained using the following formula: And when the equivalent wave vector angle before modulation For small angles, the maximum non-diffraction distance after modulation can be obtained using the following approximate formula: in, This represents the maximum non-diffraction distance after modulation. For a finite aperture radius.

[0011] Furthermore, the complex amplitude distribution of the zero-order Bessel electromagnetic beam is obtained by the following formula: in, For complex amplitude distribution, It is a zeroth-order Bessel function of the first kind. Radial wave vector, For wave vector, , , The equivalent wave vector angle before modulation. For wavelength, The coordinates are the horizontal and radial coordinates.

[0012] Furthermore, the method for pre-reconstructing the initial input plane field of the zero-order Bessel electromagnetic beam generation system includes: Applying a pre-reconstruction function in the frequency domain The relationship between the pre-reconstructed initial planar field distribution and the unreconstructed initial planar field distribution can be obtained using the following formula: in, This represents the initial planar field distribution after pre-reconstruction. The initial planar field distribution before pre-reconstruction. Represents a two-dimensional Fourier transform. This represents the two-dimensional inverse Fourier transform. , For frequency domain coordinates, For transmission distance, Pre-reconstruction factor; The pre-reconstruction function is expressed as follows: And satisfy the constraints: in, This represents an exponential function with the natural constant as its base. The imaginary unit, For wave vector, For wavelength, , These are spatial frequency coordinates.

[0013] According to a second technical solution of the present invention, a spatial domain linear phase modulation and energy efficiency optimization system is provided, the system comprising: The complex amplitude distribution acquisition module is configured to acquire the complex amplitude distribution on the output transverse plane of the zero-order Bessel electromagnetic beam generation system while keeping the existing zero-order Bessel electromagnetic beam generation system structure and finite aperture radius unchanged. The phase modulation module is configured to apply spatial domain linear phase modulation that is linearly related to the transverse radial coordinate to the complex amplitude distribution to obtain the modulated complex amplitude distribution. The modulated parameter determination module is configured to determine the modulated angular spectral ring radius, equivalent wave vector angle, and maximum non-diffraction distance based on the spatial domain linear phase modulation, while keeping the finite aperture radius unchanged. The pre-reconstruction processing module is configured to select a pre-reconstruction factor based on the maximum non-diffraction distance and perform pre-reconstruction processing on the initial input plane field of the zero-order Bessel electromagnetic beam generation system to obtain the pre-reconstructed initial plane field distribution.

[0014] According to a third technical solution of the present invention, an electronic device is provided, the electronic device comprising: a memory for storing a computer program; and a processor for executing the computer program to implement the method described above.

[0015] According to a fourth technical solution of the present invention, a non-transitory computer-readable storage medium storing instructions is provided, which, when executed by a processor, performs the method described above.

[0016] The spatial domain linear phase modulation and energy efficiency optimization methods, systems, devices, and media according to various embodiments of the present invention have at least the following technical effects: a) This invention can improve the non-diffraction distance, specifically by increasing the transverse radial coordinate. By applying spatial domain linear phase modulation, the radius of the angular spectral ring and the equivalent wave vector angle are reduced, thereby increasing the maximum diffraction-free distance under finite aperture conditions. It can effectively overcome the problem of limited non-diffraction distance caused by the difficulty in further reducing the wave vector angle in existing generation systems.

[0017] (b) This invention can be implemented without changing the original generation structure and has strong compatibility. Specifically, this invention pertains to the back-end control method of zero-order Bessel electromagnetic beams, and can be implemented without changing the original Bessel beam generation system structure and aperture radius, making it easy to integrate with or upgrade existing systems.

[0018] c) This invention provides the correspondence between spatial domain linear phase modulation and angular spectral domain convolutional translation, which can be derived from... , as well as By establishing a calculable mapping between modulation factor, equivalent wave vector angle, and maximum non-diffraction distance, the improvement in non-diffraction distance becomes predictable and designable.

[0019] d) The present invention achieves adjustable enhancement through modulation factor. Specifically, with modulation factor as an adjustable parameter, the degree of diagonal spectral ring shrinkage and the magnitude of the enhancement of non-diffraction distance can be continuously controlled, which is convenient for parameter matching for different apertures, different wavelengths and different target propagation distances.

[0020] e) To address the potential decrease in spatial energy efficiency caused by spatial domain linear phase modulation, this invention further introduces a pre-reconstruction factor. The pre-reconstruction process involves applying a pre-reconstruction function in the frequency domain. The input field is pre-shaped to compensate for and optimize the spatial energy efficiency at the target propagation distance.

[0021] f) The implementation results show that when the spatial domain linear phase modulation factor is too large, the spatial energy efficiency decreases more significantly and may cause beam distortion. This invention introduces an energy efficiency optimization step and makes reasonable selection of the modulation factor during implementation, so that the trade-off between the improvement of the non-diffraction distance and the energy efficiency / beam quality is clearer, which is conducive to the robust parameter selection in engineering applications.

[0022] g) The method of the present invention has no strict requirements on the waveband, can be implemented in multiple wavebands, and can load the spatial domain linear phase distribution through electromagnetic metasurfaces or other phase modulation devices, thus having strong implementation flexibility and portability.

[0023] Additional aspects and advantages of the invention will be set forth in part in the description which follows, and in part will be obvious from the description, or may be learned by practice of the invention. Attached Figure Description

[0024] The above and / or additional aspects and advantages of the present invention will become apparent and readily understood from the following description of the embodiments taken in conjunction with the accompanying drawings, wherein: Figure 1 This is a schematic diagram illustrating the working principle of a spatial domain linear phase modulation and energy efficiency optimization method provided in an embodiment of the present invention. Figure 2 A flowchart illustrating a spatial domain linear phase modulation and energy efficiency optimization method provided in an embodiment of the present invention; Figure 3 This is a schematic diagram of the spatial domain linear phase modulation mechanism provided in an embodiment of the present invention; Figure 4 This is a schematic diagram comparing the frequency domain angular spectrum distribution under different modulation factor conditions provided in an embodiment of the present invention; Figure 5 A schematic diagram of the propagation electric field distribution of a zero-order Bessel electromagnetic beam in the xoz plane under different modulation factors provided in this embodiment of the invention; Figure 6 This is a schematic diagram comparing the changes in spatial energy efficiency with propagation distance under different modulation factors provided in this embodiment of the invention. Figure 7 This is a structural diagram of a spatial domain linear phase modulation and energy efficiency optimization system provided in an embodiment of the present invention. Detailed Implementation

[0025] To enable those skilled in the art to better understand the technical solution of the present invention, the present invention will be described in detail below with reference to the accompanying drawings and specific embodiments.

[0026] This invention provides a spatial domain linear phase modulation and energy efficiency optimization method. Please refer to [link to relevant documentation]. Figure 1 This is a schematic diagram illustrating the working principle of a spatial domain linear phase modulation and energy efficiency optimization method provided in this embodiment of the invention. It shows the key parameter relationships between the zero-order Bessel electromagnetic beam generation system, the phase modulation device, and the output beam, as well as the process of improving the diffraction-free distance through spatial domain linear phase modulation. Specifically, a Gaussian wave or plane wave is input as the incident wave to the Bessel beam generation module. The Bessel beam generation module converts the incident wave into an initial zero-order Bessel electromagnetic beam and outputs it to the phase modulation device. The total wave vector of the initial zero-order Bessel electromagnetic beam is... k The total wave vector can be decomposed into radial components. k r With axial component k z Total wave vector and propagation axis z The included angle is the equivalent wave vector angle. θ Under the constraint of a finite aperture radius, the maximum diffraction-free distance of the initial zero-order Bessel electromagnetic beam is z max The phase modulation device applies spatial domain linear phase modulation to the incident initial zero-order Bessel electromagnetic beam, reducing the equivalent wave vector angle of the output beam after modulation to... θ c While maintaining the original finite aperture radius, the maximum diffraction-free distance of the modulated zero-order Bessel electromagnetic beam is extended to [value missing]. z cmax . Figure 1 The radial coordinates in the angular spectral domain are also shown. ρ The three-dimensional spatial intensity distribution of the zero-order Bessel electromagnetic beam reveals the typical beam characteristics of a highly concentrated central main lobe energy of the zero-order Bessel electromagnetic beam. The entire system adopts an architecture of cascaded Bessel beam generation module and phase modulation device. There is no need to modify the internal structure and aperture parameters of the original Bessel beam generation module. The effective improvement of the diffraction-free distance can be achieved simply by back-end phase modulation.

[0027] Therefore, this method can be directly applied to the output transverse plane of existing zero-order Bessel electromagnetic beam generation systems without involving the interception of the initial wave propagation and time reversal, nor does it rely on the expansion of physical aperture or equivalent aperture to achieve diffraction-free distance enhancement.

[0028] Based on the above working principle, please further combine Figure 2As shown, the spatial domain linear phase modulation and energy efficiency optimization method includes the following steps S10-S40.

[0029] S10: Under the condition of keeping the existing zero-order Bessel electromagnetic beam generation system structure and finite aperture radius unchanged, obtain the complex amplitude distribution on the output transverse plane of the zero-order Bessel electromagnetic beam generation system.

[0030] The purpose of step S10 is to directly utilize the output field of the existing system without modifying the original generation system, thus ensuring the compatibility and convenience of the method. By obtaining the complex amplitude distribution on the output transverse plane, a clear control target is provided for subsequent linear phase modulation, enabling the improvement of the diffraction-free distance to be achieved without changing the physical structure of the system.

[0031] It should be noted that the zero-order Bessel electromagnetic beam generation system mentioned in this article refers to any existing device or system capable of generating a zero-order Bessel electromagnetic beam, such as beam generation structures built based on principles like axial pyramids, spatial light modulators, annular slit-lens combinations, or electromagnetic metasurfaces. These systems have been widely used in free-space optical communication, terahertz imaging, and wireless power transmission, and their output characteristics are well-known to those skilled in the art. The method of this invention directly acts on the output transverse plane of this existing system without modifying any internal components, thus offering the advantage of plug-and-play backend control.

[0032] S20: Apply spatial domain linear phase modulation that is linearly related to the transverse and radial coordinates to the complex amplitude distribution to obtain the modulated complex amplitude distribution.

[0033] Step S20 introduces a linear phase factor in the spatial domain to change the transverse phase distribution of the beam, thereby effectively compressing the angular spectral ring radius. Linear phase modulation reduces the original wave vector angle, creating conditions for extending the diffraction-free distance under finite aperture conditions. Furthermore, by adjusting the magnitude of the modulation factor, the degree of reduction in the wave vector angle can be continuously controlled, thus achieving flexible control of the diffraction-free distance.

[0034] In one specific embodiment, such as Figure 1 As shown, the transverse complex amplitude distribution of the zero-order Bessel electromagnetic beam is obtained without changing the original structure and aperture radius of the zero-order Bessel electromagnetic beam generation system. ,in For the horizontal and radial coordinates. Loading linear phase factor The modulated complex amplitude distribution is obtained. : in, For modulation factor, The imaginary unit, is the base of the natural logarithm.

[0035] S30: Based on spatial domain linear phase modulation, determine the modulated angular spectral ring radius, equivalent wave vector angle, and maximum non-diffraction distance while keeping the finite aperture radius unchanged.

[0036] Step S30 utilizes the translation property of Fourier transform to establish a quantitative relationship between the modulation factor, the angular spectral ring radius, and the equivalent wave vector angle, and further calculates the maximum diffraction-free distance under a given finite aperture radius. This calculation process has a clear analytical expression, making the improvement in diffraction-free distance predictable and designable, facilitating the selection of a suitable modulation factor according to actual engineering needs.

[0037] Specifically, such as Figure 3 The diagram shown is a schematic representation of the spatial domain linear phase modulation mechanism provided in an embodiment of the present invention, illustrating the modulation of the input complex amplitude. After applying linear phase modulation, the radius of the angular spectral ring is reduced from... Shrink to This increases the non-diffraction distance. Figure 3 The left side of the middle section represents the spatial coordinate system. x and y Using horizontal rectangular coordinates, r Let be the transverse and radial coordinates. The complex amplitude distribution of the initial zero-order Bessel electromagnetic beam in the spatial domain is: Its effective radial range is determined by r 0 characterization. For the complex amplitude distribution in the spatial domain. Loading phase factor Phase modulation is performed, where c The modulation factor ensures that the radial range of the modulated spatial field remains unchanged. The right side of the figure represents the frequency domain, i.e., the angular spectral domain coordinate system. f x and f y They are respectively x direction and y Spatial frequency of direction, Let be the radial coordinates in the frequency domain. The initial zero-order Bessel electromagnetic beam's angular spectrum distribution in the frequency domain is: F ( ρ ), presented as a radius of The ring-shaped distribution is called the angular spectral ring. Based on the spatial domain multiplication property of Fourier transform corresponding to frequency domain convolution and translation, spatial domain linear phase modulation will produce an angular spectral scaling effect in the frequency domain, causing the radius of the angular spectral ring to change from the initial value. Shrink to And satisfy The quantitative relationship is that the reduction in the radius of the angular spectral ring directly corresponds to the reduction in the equivalent wave vector angle, thereby improving the maximum non-diffraction distance of the zero-order Bessel electromagnetic beam under finite aperture conditions.

[0038] In one specific embodiment, based on the aforementioned spatial domain linear phase modulation mechanism, and utilizing the properties of Fourier transform, spatial domain multiplication is equivalent to angular spectral domain convolution. For a zero-order Bessel beam, when Its angular spectrum initially appears as an angular spectral ring; after applying spatial domain linear phase modulation, while maintaining the original finite aperture radius, the angular spectral ring shrinks, and its radius decreases from... Become ,in, The radius of the modulated angular spectral ring. The radius of the angular spectral ring before modulation. It is a zeroth-order Bessel function of the first kind. Radial wave vector, For wave vector, , , The equivalent wave vector angle before modulation. For wavelength, The coordinates are the horizontal and radial coordinates.

[0039] Correspondingly, the modulated equivalent wave vector angle is changed from... It becomes: in, The equivalent wave vector angle after modulation. The equivalent wave vector angle before modulation. λ is the wavelength.

[0040] With a finite aperture radius Under finite aperture conditions, the maximum non-diffraction distance is determined by Revised to: when When the angle is small, it can be approximated as: in, This represents the maximum non-diffraction distance after modulation. For a finite aperture radius.

[0041] Based on the above modulated equivalent wave vector angle and maximum non-diffraction distance The calculation formula for modulation factor The selection of the modulation factor directly affects the improvement in the diffraction-free distance and also changes the space energy efficiency. The following explanation, based on simulation results, illustrates this modulation factor. The role of and the matching relationship when selecting .

[0042] like Figure 4 and Figure 5 As shown, where Figure 4 This is a schematic diagram comparing the frequency domain angular spectrum distribution under different modulation factor conditions provided in the embodiments of the present invention. It is used to characterize the trend of the angular spectrum ring changing with the modulation factor and to show the influence of spatial domain phase modulation on the angular spectrum ring. Figure 5 This diagram illustrates the propagation electric field distribution of a zero-order Bessel electromagnetic beam in the xoz plane under different modulation factors, as provided in this embodiment of the invention. It serves to explain the improvement in propagation distance without diffraction and demonstrates the change in the beam center position under different modulation factors. Figure 4 and Figure 5 It can be seen that, with the modulation factor Increasing the modulation factor reduces the angular spectral ring radius and the equivalent wave vector angle, thus increasing the theoretical maximum non-diffraction distance, consistent with the simulation results. Under representative conditions of N=256 and θ=2°, when the modulation factor... When the modulation factor is set to 0.1, 0.2, and 0.3 respectively, the corresponding non-diffraction distance can be increased from 67.7m to 79.4m, 93.7m, and 113m, indicating that the present invention can improve the diffraction distance through modulation factor adjustment. Achieve continuously adjustable enhancement of diffraction-free distance.

[0043] Meanwhile, spatial domain linear phase modulation may cause a decrease in spatial energy efficiency, and this decrease is more pronounced when the modulation factor is too large, potentially leading to beam distortion. Therefore, the modulation factor... A trade-off should be made between improving the non-diffraction distance and energy efficiency / beam quality.

[0044] S40: Select the pre-reconstruction factor based on the maximum non-diffraction distance, and perform pre-reconstruction processing on the initial input plane field of the zero-order Bessel electromagnetic beam generation system to obtain the pre-reconstructed initial plane field distribution.

[0045] Step S40 aims to compensate for the decrease in spatial energy efficiency caused by linear phase modulation in the spatial domain. Since phase modulation changes the energy distribution of the beam while increasing the diffraction-free distance, resulting in a decrease in energy concentration at the target distance, selecting an appropriate pre-reconstruction factor based on the determined maximum diffraction-free distance and pre-shaping the initial input plane field in the frequency domain can effectively restore or optimize the spatial energy efficiency at the target distance, thereby achieving a balance between increasing the diffraction-free distance and energy efficiency.

[0046] In one specific embodiment, to compensate for the decrease in spatial energy efficiency caused by spatial domain linear phase modulation, such as Figure 6The diagram illustrates the comparison of spatial energy efficiency with propagation distance under different modulation factors according to an embodiment of the present invention. It explains the trend of energy efficiency changes caused by phase modulation and shows the decrease and increase in spatial energy efficiency under different modulation factors. The horizontal axis represents the propagation distance z of the electromagnetic wave, in meters, and the vertical axis represents the spatial energy efficiency η, used to visually characterize the influence of spatial domain linear phase modulation on beam energy concentration and the energy compensation effect of pre-reconstruction processing. The diagram contains three curves corresponding to different modulation factors. c =0.1, c =0.2, c =0.3. All three curves exhibit similar trends. Within the propagation distance range of 0 to 40m, the spatial energy efficiency remains at a relatively high level close to 1 and is basically stable, indicating that the energy concentration of the beam does not significantly decrease within this distance. When the propagation distance exceeds 40m, the spatial energy efficiency begins to gradually decrease with increasing propagation distance. Furthermore, the larger the modulation factor, the later the propagation distance at which the spatial energy efficiency begins to decrease significantly, corresponding to a longer diffraction-free distance for the zero-order Bessel electromagnetic beam. This verifies the effect of spatial domain linear phase modulation on improving the diffraction-free distance. A marked point in the figure corresponds to the modulation factor. c The spatial energy efficiency at the maximum non-diffraction distance when the coefficient of performance (COP) is 0.1 is 92.95%, an improvement of 1.94% compared to the case without pre-reconstruction processing; one marker point corresponds to a modulation factor. c The spatial energy efficiency at the maximum non-diffraction distance when the coefficient of performance (COP) is 0.2 is 92.36%, an improvement of 1.24% compared to the case without pre-reconstruction processing; one marker point corresponds to a modulation factor. c The spatial energy efficiency at the maximum diffraction-free distance when the modulation index (MCI) is 0.3 is 89.76%, which is 1.83% higher than that without pre-reconstruction processing. These results demonstrate that the pre-reconstruction processing introduced in this invention can effectively compensate for the decrease in spatial energy efficiency caused by linear phase modulation in the spatial domain. It significantly improves the spatial energy efficiency at the target's diffraction-free distance under different modulation factor conditions, achieving a synergistic balance between improving the diffraction-free distance and optimizing energy efficiency. This provides a clear experimental basis for the rational selection of modulation factors in engineering applications.

[0047] This embodiment introduces a pre-reconstruction factor to pre-reconstruct the input field. The selection of the pre-reconstruction factor is directly related to the maximum non-diffraction distance determined in step S30. Specifically, based on the target non-diffraction distance, the corresponding pre-reconstruction factor value is determined through numerical simulation or empirical lookup tables, so that the initial planar field after pre-reconstruction achieves optimal spatial energy efficiency or meets system requirements when propagating to the maximum non-diffraction distance. For example, the pre-reconstruction factor is selected under the condition of a theoretical maximum non-diffraction distance of approximately 62.3 m. By appropriately selecting the pre-reconstruction factor, it is possible to achieve different modulation factors. This improves the spatial energy efficiency at the maximum non-diffraction distance, thereby achieving energy efficiency compensation optimization. The initial planar field distribution after pre-reconstruction satisfies: in, This represents the initial planar field distribution after pre-reconstruction. The initial planar field distribution before pre-reconstruction. Represents a two-dimensional Fourier transform. This represents the two-dimensional inverse Fourier transform. , For frequency domain coordinates, For transmission distance, Pre-reconstruction factor; The pre-reconstruction function is expressed as follows: And satisfy the constraints: in, This represents an exponential function with the natural constant as its base. The imaginary unit, For wave number, For wavelength, , These are spatial frequency coordinates.

[0048] It should be noted that the method of this invention is not limited to a specific operating band in principle, but its applicability needs to be evaluated in conjunction with factors such as the electromagnetic wave propagation characteristics, device processing accuracy, and material dispersion in the specific frequency band. It has potential applications in microwave, terahertz, infrared, and visible light bands. In actual implementation, the modulation factor and pre-reconstruction parameters need to be adapted accordingly according to the target band. The spatial domain linear phase modulation described in step S20 can be implemented using electromagnetic metasurfaces, spatial light modulators, or other phase modulation devices capable of loading linear phase distributions, provided that subwavelength phase modulation capability is available. The selection of specific devices needs to comprehensively consider the operating wavelength, insertion loss, phase resolution, and system integration requirements to ensure the reliability of the modulation effect and engineering feasibility.

[0049] Another aspect of the present invention provides a spatial domain linear phase modulation and energy efficiency optimization system, such as... Figure 7 The diagram shown is a structural diagram of a spatial domain linear phase modulation and energy efficiency optimization system provided in an embodiment of the present invention. The spatial domain linear phase modulation and energy efficiency optimization system includes: The complex amplitude distribution acquisition module 701 is configured to acquire the complex amplitude distribution on the output transverse plane of the zero-order Bessel electromagnetic beam generation system while keeping the existing zero-order Bessel electromagnetic beam generation system structure and finite aperture radius unchanged. Phase modulation module 702 is configured to apply spatial domain linear phase modulation that is linearly related to the transverse radial coordinate to the complex amplitude distribution to obtain the modulated complex amplitude distribution. The modulated parameter determination module 703 is configured to determine the modulated angular spectral ring radius, equivalent wave vector angle, and maximum non-diffraction distance based on the spatial domain linear phase modulation, while keeping the finite aperture radius unchanged. The pre-reconstruction processing module 704 is configured to select a pre-reconstruction factor based on the maximum non-diffraction distance and perform pre-reconstruction processing on the initial input plane field of the zero-order Bessel electromagnetic beam generation system to obtain the pre-reconstructed initial plane field distribution.

[0050] Another aspect of the present invention provides an electronic device, comprising: a controller; and a memory for storing one or more programs, which, when executed by the controller, perform the methods described in the various embodiments above.

[0051] Another aspect of the present invention provides a computer-readable storage medium having a computer program stored thereon, which, when executed by a processor, implements the method as described above. This computer-readable storage medium may be included in the electronic device described in the above embodiments, or it may exist independently without being assembled into the electronic device.

[0052] Another aspect of the present invention provides a computer program product or computer program including computer instructions stored in a computer-readable storage medium. A processor of a computer device reads the computer instructions from the computer-readable storage medium and executes the computer instructions, causing the computer device to perform the methods provided in the various embodiments described above.

[0053] According to one aspect of the present invention, a computer system is also provided, including a central processing unit (CPU) that can perform various appropriate actions and processes, such as executing the methods described above, based on a program stored in read-only memory (ROM) or a program loaded from storage into random access memory (RAM). The RAM also stores various programs and data required for system operation. The CPU, ROM, and RAM are interconnected via a bus. Input / output (I / O) interfaces are also connected to the bus.

[0054] The following components are connected to the I / O interface: input components including keyboards, mice, etc.; output components including cathode ray tubes (CRTs), liquid crystal displays (LCDs), and speakers; storage components including hard drives; and communication components including network interface cards such as LAN (Local Area Network) cards and modems. The communication components perform communication processing via networks such as the Internet. Drives are also connected to the I / O interface as needed. Removable media, such as disks, optical discs, magneto-optical discs, semiconductor memories, etc., are installed on the drive as needed so that computer programs read from them can be installed into the storage components as required.

[0055] In particular, according to embodiments of the present invention, the processes described above with reference to the flowcharts can be implemented as computer software programs. For example, embodiments of the present invention include a computer program product comprising a computer program carried on a computer-readable medium, the computer program containing computer programs for performing the methods shown in the flowcharts. In such embodiments, the computer program can be downloaded and installed from a network via a communication component, and / or installed from a removable medium. When the computer program is executed by a central processing unit (CPU), it performs various functions defined in the system of the present invention.

[0056] It should be noted that the computer-readable medium shown in the embodiments of the present invention can be a computer-readable signal medium or a computer-readable storage medium, or any combination thereof. A computer-readable storage medium can be, for example, an electrical, magnetic, optical, electromagnetic, infrared, or semiconductor system, apparatus, or device, or any combination thereof. More specific examples of a computer-readable storage medium may include, but are not limited to: an electrical connection having one or more wires, a portable computer disk, a hard disk, random access memory (RAM), read-only memory (ROM), erasable programmable read-only memory (EPROM), flash memory, optical fiber, portable compact disc read-only memory (CD-ROM), optical storage device, magnetic storage device, or any suitable combination thereof. In the present invention, a computer-readable storage medium can be any tangible medium containing or storing a program that can be used by or in conjunction with an instruction execution system, apparatus, or device. In the present invention, a computer-readable signal medium can include a data signal propagated in baseband or as part of a carrier wave, carrying a computer-readable computer program. Such propagated data signals can take various forms, including but not limited to electromagnetic signals, optical signals, or any suitable combination thereof. Computer-readable signal media can also be any computer-readable medium other than computer-readable storage media, which can send, propagate, or transmit a program for use by or in connection with an instruction execution system, apparatus, or device. The computer program contained on the computer-readable medium can be transmitted using any suitable medium, including but not limited to wireless, wired, etc., or any suitable combination thereof.

[0057] The flowcharts and block diagrams in the accompanying drawings illustrate the architecture, functionality, and operation of possible implementations of systems, methods, and computer program products according to various embodiments of the present invention. Each block in a flowchart or block diagram may represent a module, segment, or portion of code, which contains one or more executable instructions for implementing a specified logical function. It should also be noted that in some alternative implementations, the functions indicated in the blocks may occur in a different order than those indicated in the drawings. For example, two consecutively indicated blocks may actually be executed substantially in parallel, or they may sometimes be executed in reverse order, depending on the functions involved. It should also be noted that each block in a block diagram or flowchart, and combinations of blocks in a block diagram or flowchart, may be implemented using a dedicated hardware-based system that performs the specified function or operation, or using a combination of dedicated hardware and computer instructions.

[0058] The module units described in the embodiments of the present invention can be implemented in software or hardware, and the described units can also be located in a processor. The names of these units do not necessarily limit the specific unit itself.

[0059] The above embodiments are only used to illustrate the present invention and are not intended to limit the present invention. Those skilled in the art can make various changes and modifications without departing from the spirit and scope of the present invention. Therefore, all equivalent technical solutions also fall within the scope of the present invention, and the patent protection scope of the present invention should be defined by the claims.

Claims

1. A spatial domain linear phase modulation and energy efficiency optimization method, characterized in that, The method includes: While keeping the existing zero-order Bessel electromagnetic beam generation system structure and finite aperture radius unchanged, obtain the complex amplitude distribution on the output transverse plane of the zero-order Bessel electromagnetic beam generation system; The complex amplitude distribution is subjected to spatial domain linear phase modulation that is linearly related to the transverse and radial coordinates to obtain the modulated complex amplitude distribution. Based on the spatial domain linear phase modulation, while keeping the finite aperture radius unchanged, the modulated angular spectral ring radius, equivalent wave vector angle, and maximum non-diffraction distance are determined. The pre-reconstruction factor is selected based on the maximum non-diffraction distance, and the initial input plane field of the zero-order Bessel electromagnetic beam generation system is pre-reconstructed to obtain the pre-reconstructed initial plane field distribution.

2. The spatial domain linear phase modulation and energy efficiency optimization method according to claim 1, characterized in that, The modulated complex amplitude distribution can be obtained using the following formula: in, The complex amplitude distribution before modulation. This represents the modulated complex amplitude distribution. For modulation factor, The horizontal and radial coordinates are... The imaginary unit, is the base of the natural logarithm.

3. The spatial domain linear phase modulation and energy efficiency optimization method according to claim 2, characterized in that, The radius of the modulated angular spectral ring can be obtained using the following formula: in, The radius of the modulated angular spectral ring. The radius of the angular spectral ring before modulation.

4. The spatial domain linear phase modulation and energy efficiency optimization method according to claim 2, characterized in that, The modulated equivalent wave vector angle can be obtained using the following formula: in, The equivalent wave vector angle after modulation. The equivalent wave vector angle before modulation. λ is the wavelength.

5. The spatial domain linear phase modulation and energy efficiency optimization method according to claim 4, characterized in that, The maximum non-diffraction distance after modulation can be obtained using the following formula: And when the equivalent wave vector angle before modulation For small angles, the maximum non-diffraction distance after modulation can be obtained using the following approximate formula: in, This represents the maximum non-diffraction distance after modulation. For a finite aperture radius.

6. The spatial domain linear phase modulation and energy efficiency optimization method according to claim 1, characterized in that, The complex amplitude distribution of the zero-order Bessel electromagnetic beam is obtained by the following formula: in, For complex amplitude distribution, It is a zeroth-order Bessel function of the first kind. Radial wave vector, For wave vector, , , The equivalent wave vector angle before modulation. For wavelength, The coordinates are the horizontal and radial coordinates.

7. The spatial domain linear phase modulation and energy efficiency optimization method according to claim 1, characterized in that, The methods for pre-reconstructing the initial input plane field of the zero-order Bessel electromagnetic beam generation system include: After applying the pre-reconstruction function in the frequency domain, the relationship between the pre-reconstructed initial planar field distribution and the unreconstructed initial planar field distribution can be obtained using the following formula: in, This represents the initial planar field distribution after pre-reconstruction. The initial planar field distribution before pre-reconstruction. Represents a two-dimensional Fourier transform. This represents the two-dimensional inverse Fourier transform. , For frequency domain coordinates, For transmission distance, Pick hour For pre-reconstruction functions, Pre-reconstruction factor; The pre-reconstruction function is expressed as follows: And satisfy the constraints: in, This represents an exponential function with the natural constant as its base. The imaginary unit, For wave vector, For wavelength, , These are spatial frequency coordinates.

8. A spatial domain linear phase modulation and energy efficiency optimization system, characterized in that, The system includes: The complex amplitude distribution acquisition module is configured to acquire the complex amplitude distribution on the output transverse plane of the zero-order Bessel electromagnetic beam generation system while keeping the existing zero-order Bessel electromagnetic beam generation system structure and finite aperture radius unchanged. The phase modulation module is configured to apply spatial domain linear phase modulation that is linearly related to the transverse radial coordinate to the complex amplitude distribution to obtain the modulated complex amplitude distribution. The modulated parameter determination module is configured to determine the modulated angular spectral ring radius, equivalent wave vector angle, and maximum non-diffraction distance based on the spatial domain linear phase modulation, while keeping the finite aperture radius unchanged. The pre-reconstruction processing module is configured to select a pre-reconstruction factor based on the maximum non-diffraction distance and perform pre-reconstruction processing on the initial input plane field of the zero-order Bessel electromagnetic beam generation system to obtain the pre-reconstructed initial plane field distribution.

9. An electronic device, characterized in that, The electronic device includes: Memory, used to store computer programs; A processor for executing the computer program to implement the method as described in any one of claims 1 to 7.

10. A non-transitory computer-readable storage medium storing instructions, characterized in that, When the instructions are executed by the processor, the method according to any one of claims 1 to 7 is performed.

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