RIS array beam forming method and device and processor readable storage medium

Abstract

The embodiment of the invention relates to an RIS array beam forming method and device and a processor readable storage medium. The method comprises the following steps: traversing a scannable beam direction of an RIS array to carry out beam scanning; obtaining the phase of each array element in the RIS array during each wave beam scanning; and determining a discrete phase value of each array element in the RIS array based on the obtained phases. According to the technical scheme provided by the embodiment of the invention, the discrete phase value of each array element in the RIS array is determined according to the phase of each array element in the RIS array during each wave beam scanning, so that the array element phase quantization state of the RIS array is unbound, and a limited number of different phase quantization values are configured for different RIS array adjustable units according to the requirements of different array elements. On the premise of not increasing quantization bits of the RIS array, not increasing switch cost and not increasing control complexity, the beam control precision of the RIS array is improved.

Description

Technical Field

[0001] The embodiments of the present invention relate to the field of wireless mobile communication technology, and in particular to a RIS array beamforming method, device and processor-readable storage medium. Background Art

[0002] The accuracy of the beam control of the Reconfigurable Intelligence Surface (RIS) is affected by the phase quantization accuracy of the adjustable unit in the RIS array. Common RIS arrays include 1-bit RIS array, 2-bit RIS array, and 3-bit RIS array. The beam control accuracy of the 3-bit RIS array has met certain engineering requirements. However, it is limited by the discretization of the phase state, which limits the freedom of RIS beam control.

[0003] The existing RIS beam control method is limited by the phase quantization accuracy of the adjustable unit, which limits the beam control accuracy. The common solution is to improve the phase quantization accuracy of the RIS unit, but due to the influence of cost and complexity, this method is unrealistic and does not meet the engineering conditions. Summary of the invention

[0004] Based on the above situation of the prior art, the purpose of the embodiments of the present invention is to provide a RIS array beamforming method, device and processor-readable storage medium, which can improve the beam control accuracy of RIS by relaxing the phase optional range of RIS adjustable units without increasing the number of RIS quantization bits.

[0005] To achieve the above object, according to a first aspect of the present invention, there is provided an adjustable intelligent metasurface RIS array beamforming method, the method comprising:

[0006] Traversing the scannable beam directions of the RIS array to perform beam scanning;

[0007] Acquire the phase of each array element in the RIS array during each beam scan;

[0008] Based on the acquired phase, a discrete phase value of each array element in the RIS array is determined, and the discrete phase value is used to determine the angle of RIS array beamforming.

[0009] Further, the traversing the scannable beam direction of the RIS array to perform beam scanning includes:

[0010] The beam weight of the RIS array is set to a low sidelobe weight, and beam scanning is performed based on the set weight.

[0011] Further, the traversing the scannable beam direction of the RIS array to perform beam scanning includes:

[0012] The scannable beam directions of the RIS array are traversed separately in at least two different dimensions.

[0013] Further, the determining of the discrete phase value of each array element in the RIS array includes determining the discrete phase value of each array element in the RIS array according to the following formula:

[0014]

[0015] The RIS array is an array of n-bit k×k array elements, where n is a positive integer and k is a natural number greater than or equal to 2; represents the discrete phase value of the target array element, i represents the number of discrete phase values, i=1,2,……,2 n ; represents the phase of the target array element obtained during beam scanning, j = 1, 2, ..., L, L represents the number of phases of the target array element obtained during beam scanning, m represents the array element number, m = 1, 2, ..., k 2 ; f() represents the clustering function.

[0016] Furthermore, the discrete phase value is used to determine the angle of RIS array beamforming, specifically:

[0017] The phase of each array element in the RIS array is adjusted according to the determined discrete phase value to obtain the angle of RIS array beamforming.

[0018] Furthermore, the method further comprises:

[0019] The adjusted RIS array is searched for beamforming weights.

[0020] Furthermore, the method further comprises:

[0021] Generating a beamforming weight matrix of the RIS array according to the determined discrete phase values;

[0022] The beamforming weight matrix is ​​stored.

[0023] According to a second aspect of the present invention, a RIS array beamforming device is provided, comprising a memory, a transceiver and a processor:

[0024] Memory for storing computer programs;

[0025] a transceiver, for transmitting and receiving data under the control of the processor;

[0026] A processor is configured to read the computer program in the memory and perform the following operations:

[0027] Traversing the scannable beam directions of the RIS array to perform beam scanning;

[0028] Acquire the phase of each array element in the RIS array during each beam scan;

[0029] Based on the acquired phase, a discrete phase value of each array element in the RIS array is determined, and the discrete phase value is used to determine the angle of RIS array beamforming.

[0030] Further, the traversing the scannable beam direction of the RIS array to perform beam scanning includes:

[0031] The beam weight of the RIS array is set to a low sidelobe weight, and beam scanning is performed based on the set weight.

[0032] Further, the traversing the scannable beam direction of the RIS array to perform beam scanning includes:

[0033] The scannable beam directions of the RIS array are traversed separately in at least two different dimensions.

[0034] Further, the determining of the discrete phase value of each array element in the RIS array includes determining the discrete phase value of each array element in the RIS array according to the following formula:

[0035]

[0036] The RIS array is an array of n-bit k×k array elements, where n is a positive integer and k is a natural number greater than or equal to 2; represents the discrete phase value of the target array element, i represents the number of discrete phase values, i=1,2,……,2 n ; represents the phase of the target array element obtained during beam scanning, j = 1, 2, ..., L, L represents the number of phases of the target array element obtained during beam scanning, m represents the array element number, m = 1, 2, ..., k 2 ; f() represents the clustering function.

[0037] Furthermore, the discrete phase value is used to determine the angle of RIS array beamforming, specifically:

[0038] The phase of each array element in the RIS array is adjusted according to the determined discrete phase value to obtain the angle of RIS array beamforming.

[0039] Furthermore, the processor also performs the following operations:

[0040] The adjusted RIS array is searched for beamforming weights.

[0041] Furthermore, the processor also performs the following operations:

[0042] Generating a beamforming weight matrix of the RIS array according to the determined discrete phase values;

[0043] The beamforming weight matrix is ​​stored.

[0044] According to a third aspect of the present invention, a RIS array beamforming device is provided, the device comprising:

[0045] A traversal unit, used for traversing the scannable beam directions of the RIS array to perform beam scanning;

[0046] A phase acquisition unit, used to acquire the phase of each array element in the RIS array during each beam scanning;

[0047] The discrete phase value determining unit is used to determine the discrete phase value of each array element in the RIS array based on the acquired phase, and the discrete phase value is used to determine the angle of RIS array beamforming.

[0048] According to a fourth aspect of the present invention, there is provided a processor-readable storage medium storing a program for causing the processor to execute the method described in the first aspect of the present invention.

[0049] In summary, the embodiments of the present invention provide a RIS array beamforming method, device and processor-readable storage medium, the method comprising: traversing the scannable beam direction of the RIS array to perform beam scanning; obtaining the phase of each array element in the RIS array during each beam scanning; and determining the discrete phase value of each array element in the RIS array based on the obtained phase. The technical solution provided by the embodiments of the present invention determines the discrete phase value of each array element in the RIS array according to the phase of each array element in the RIS array during each beam scanning, thereby realizing the phase quantization state of the array element of the unbinding RIS array, and configuring different finite phase quantization values ​​for different RIS array adjustable units according to the requirements of different array elements, thereby greatly improving the beamforming effect of RIS. From another perspective, the technical solution provided by the embodiments of the present invention can also use the same bit control method under the condition of limited array space, instead of expanding the array area, to still achieve the effect of improving beam control accuracy. BRIEF DESCRIPTION OF THE DRAWINGS

[0050] Figure 1 is a flow chart of a RIS array beamforming method provided by an embodiment of the present invention;

[0051] Figure 2 It is a structural schematic diagram of a RIS array beamforming device provided by an embodiment of the present invention;

[0052] Figure 3 It is a schematic structural diagram of a RIS array beamforming device provided by yet another embodiment of the present invention. DETAILED DESCRIPTION

[0053] In order to make the purpose, technical scheme and advantages of the present invention clearer, the present invention is further described in detail below in conjunction with specific embodiments and with reference to the accompanying drawings. It should be understood that these descriptions are only exemplary and are not intended to limit the scope of the present invention. In addition, in the following description, the description of well-known structures and technologies is omitted to avoid unnecessary confusion of the concept of the present invention.

[0054] It should be noted that, unless otherwise defined, the technical terms or scientific terms used in one or more embodiments of the present invention should be understood by people with ordinary skills in the field to which the present invention belongs. The words "first", "second" and similar words used in one or more embodiments of the present invention do not indicate any order, quantity or importance, but are only used to distinguish different components. "Include" or "comprise" and similar words mean that the elements or objects appearing before the word include the elements or objects listed after the word and their equivalents, without excluding other elements or objects. "Connect" or "connected" and similar words are not limited to physical or mechanical connections, but may include electrical connections, whether direct or indirect.

[0055] RIS beam control benefits from the ability to achieve similar beam control effects without the need for a large number of high-cost digital channels, and will become an important product direction in future mobile communications. The beamforming method of RIS usually achieves beam scanning by controlling the phase of all adjustable units in the RIS array. The phase control of the RIS unit is implemented by a positive-intrinsic-negative (PIN) switch. For example, a 1-bit RIS unit implements 2 discrete phase adjustments through 1 switch, and the 2 phase states are usually set to 0 / 180 degrees. Although this discrete phase control can achieve a certain degree of beam scanning effect, the beam control accuracy is usually poor, such as high side lobes and impaired gain.

[0056] In order to improve the beam control accuracy, a common method is to improve the beam control accuracy, such as 2-bit and 3-bit RIS arrays, where the 3-bit RIS unit phase control states can reach 8, which are 0 / 45 / 90 / 135 / 180 / 225 / 270 / 315 degrees, but there is still a certain degree of loss. RIS arrays with quantization accuracy of 4 bits or above require more than double the RF switches, and the production and processing costs are too high, the cost-benefit is relatively low, and there are no engineering conditions. Another method is to use a larger RIS array to compensate for the beam control problem caused by the discretization of the phase control of the RIS unit, and the expansion of the RIS array and the increase in cost are necessary. The embodiment of the present invention improves the beam control accuracy of RIS by relaxing the phase selection range of the RIS adjustable unit without increasing the number of quantization bits of the RIS array, increasing the switch cost, and increasing the control complexity.

[0057] The technical solution of the present invention is described in detail below with reference to the accompanying drawings. An embodiment of the present invention provides a RIS array beamforming method. The method provided by the embodiment of the present invention changes the phase of the adjustable unit in the traditional RIS array with fixed n bits from all array elements fixed to the same 2 n discrete phases, different array elements can choose different 2 n discrete phases, thereby unbinding the constraints on the array element phase. Figure 1 FIG. 8 is a flow chart of the RIS array beamforming method, which comprises the following steps:

[0058] S1100 , traverse the scannable beam directions of the RIS array to perform beam scanning.

[0059] S1110. Acquire the phase of each array element in the RIS array during each beam scanning.

[0060] According to certain optional embodiments, in step S1100, when the RIS array structure is fixed, the scannable beam direction of the RIS array is traversed; in step S1110, the phase state of each array element during each beam scan is recorded. The RIS array is usually an array of n-bit k×k array elements, where n is a positive integer and k is a natural number greater than or equal to 2. The bit value n of the RIS array is usually 1, 2, 3 or 4 according to the currently common RIS array phase quantization range. This embodiment of the present invention is described by taking an n-bit, k=10 RIS array as an example, that is, the RIS array has a 10×10 RIS array plane, which includes a total of 100 RIS array elements. Based on the existing beamforming theory, such as the grid of beam (GOB) method, the achievable beam pointing of the 10×10 RIS array can be traversed, and all achievable beam pointing can be scanned to obtain the phase of each of the 100 array elements of the RIS array during each beam scan, and the phase value of each of the 100 array elements can be recorded. Where m is the array element number, 1≤m≤100, j=1,2,……,L; j is the beam number, L represents the number of phases of the target array element acquired during beam scanning, and the value of L depends on the number of beams traversed by the RIS. Since the RIS array is usually a two-dimensional planar array, it is necessary to traverse the scannable beam directions of the RIS array in two different dimensions corresponding to the two-dimensional plane to traverse all beam directions of the RIS array.

[0061] According to certain optional embodiments, when traversing the beam, the beam weights of the RIS array can be set to low sidelobe weights, and beam scanning can be performed based on the set weights, so that in subsequent beamforming, discrete weights will also obtain a low sidelobe shaped beam.

[0062] S1120: Based on the acquired phase, a discrete phase value of each array element in the RIS array is determined, and the discrete phase value is used to determine the angle of RIS array beamforming. In this embodiment of the present invention, the phase of each array element in the RIS array can be adjusted according to the determined discrete phase value to obtain the angle of RIS array beamforming.

[0063] In order not to make the RIS array nThe discrete phases are not fixed at several specific phase values. For example, a typical 1-bit RIS array has two states of 0 / 180 degrees, a 2-bit RIS array has four states of 0 / 90 / 180 / 270 degrees, and a 3-bit RIS array has eight states of 0 / 45 / 90 / 135 / 180 / 225 / 270 / 315 degrees. The technical solution provided by the embodiment of the present invention can configure different discrete phases according to the phase requirements of each array element. For the mth array element, it can be seen from the traversal of the above steps that there are a total of L phase state requirements:

[0064]

[0065] A practical n-bit RIS array requires only 2 n discrete phases, usually 2 n <<L, need to find 2 of L phases n According to some optional embodiments, a clustering algorithm is used to find 2 of the L phases. n For example, a K-means clustering algorithm can be used to find the 2 phase centers of the mth array element. n The discrete phase value of each array element in the RIS array can be determined according to the following formula:

[0066]

[0067] Wherein, the RIS array is an array of n-bit k×k array elements, n is a positive integer, and k is a natural number greater than or equal to 2; The discrete phase value i represents the number of discrete phase values, i = 1, 2, ..., 2 n ; represents the phase of the target array element obtained during beam scanning, j = 1, 2, ..., L, L represents the number of phases of the target array element obtained during beam scanning, m represents the array element number, m = 1, 2, ..., k 2 ; f() represents the clustering function.

[0068] That can be expressed as:

[0069]

[0070] The embodiment of the present invention performs phase clustering for all 100 array elements in the RIS array to obtain the discrete phase value of each adjustable unit. The discrete phase values ​​of different array elements will not be consistent, nor will they be limited to several known optional phases. The restrictions on the array element phase are untied, thereby improving the freedom of beam weight selection of the RIS array and the beamforming accuracy. For example, for a 2-bit RIS array, the configurable phase of the array element does not have to be limited to the four states of 0 / 90 / 180 / 270 degrees, but for different array elements, four different phase states can be selected according to requirements. This method of unbinding the phase quantization state of the array element can greatly improve the beam control effect of the RIS. The technical solution of the embodiment of the present invention does not increase the phase quantization accuracy of the array element, and keeps the original number of bits unchanged, so the hardware complexity of the RIS array does not change.

[0071] According to some optional embodiments, the method further comprises the steps of:

[0072] performing a beamforming weight search on the adjusted RIS array; and,

[0073] A beamforming weight matrix of the RIS array is generated according to the determined discrete phase values; and the beamforming weight matrix is ​​stored.

[0074] The RIS array obtained through the above steps has different optional discrete phases for each array element. A beam weight search similar to that of a traditional RIS array can be used to verify the beamforming effect. After verification, the beamforming weight matrix of the RIS array is generated according to the determined discrete phase values; and the beamforming weight matrix is ​​stored to obtain a specific set of beamforming weights for direct use in subsequent beamforming.

[0075] An embodiment of the present invention further provides a RIS array beamforming device, Figure 2 The schematic diagram of the structure of the device is shown in FIG. Figure 2 As shown, the device includes a memory 2120, a transceiver 2110 and a processor 2100:

[0076] Memory 2120, used for storing computer programs;

[0077] A transceiver 2110, configured to send and receive data under the control of the processor 2100;

[0078] The processor 2100 is configured to read the computer program in the memory 2120 and perform the following operations:

[0079] Traversing the scannable beam directions of the RIS array to perform beam scanning;

[0080] Obtain the phase of each element in the RIS array during each beam scan;

[0081] Based on the acquired phase, a discrete phase value of each array element in the RIS array is determined, and the discrete phase value is used to determine the angle of RIS array beamforming.

[0082] It should be noted here that the above-mentioned RIS array beamforming device provided in the embodiment of the present invention can implement all the method steps implemented in the above-mentioned RIS array beamforming method embodiment, and can achieve the same technical effect. The parts and beneficial effects of this embodiment that are the same as those of the method embodiment will not be specifically repeated here.

[0083] Among them, Figure 2 In the embodiment, the bus architecture may include any number of interconnected buses and bridges, specifically one or more processors represented by the processor 2100 and various circuits of the memory represented by the memory 2120 are linked together. The bus architecture may also link together various other circuits such as peripherals, voltage regulators, and power management circuits, which are well known in the art and are therefore not further described herein. The bus interface provides an interface. The transceiver 2110 may be a plurality of components, namely, a transmitter and a receiver, providing a unit for communicating with various other devices on a transmission medium, which may include a wireless channel, a wired channel, an optical cable, and other transmission media. The processor 2100 is responsible for managing the bus architecture and general processing, and the memory may store data used by the processor 2100 when performing operations. The processor 2100 may be a central processing unit (CPU), an application specific integrated circuit (ASIC), a field programmable gate array (FPGA), or a complex programmable logic device (CPLD), and the processor may also adopt a multi-core architecture.

[0084] An embodiment of the present invention further provides a RIS array beamforming device, Figure 3 The schematic diagram of the structure of the device is shown in FIG. Figure 3 As shown, the device comprises:

[0085] A traversal unit 3100, used for traversing the scannable beam directions of the RIS array to perform beam scanning;

[0086] The phase acquisition unit 3110 is used to acquire the phase of each array element in the RIS array during each beam scanning;

[0087] The discrete phase value determining unit 3120 is used to determine the discrete phase value of each array element in the RIS array based on the acquired phase, and the discrete phase value is used to determine the angle of RIS array beamforming.

[0088] It should be noted here that the above-mentioned RIS array beamforming device provided in the embodiment of the present invention can implement all the method steps implemented in the above-mentioned RIS array beamforming method embodiment, and can achieve the same technical effect. The parts and beneficial effects of this embodiment that are the same as those of the method embodiment will not be specifically repeated here.

[0089] An embodiment of the present invention further provides a processor-readable storage medium, which stores a program, and the program is used to enable the processor to execute the method involved in the above embodiment of the present invention. The processor-readable storage medium can be any available medium or data storage device that the processor can access, including but not limited to magnetic storage (such as floppy disk, hard disk, magnetic tape, magneto-optical disk (MO), etc.), optical storage (such as CD, DVD, BD, HVD, etc.), and semiconductor storage (such as ROM, EPROM, EEPROM, non-volatile memory (NAND FLASH), solid state drive (SSD)), etc.

[0090] In summary, the embodiments of the present invention relate to a RIS array beamforming method, device and processor-readable storage medium, the method comprising: traversing the scannable beam direction of the RIS array to perform beam scanning; obtaining the phase of each array element in the RIS array during each beam scanning; and determining the discrete phase value of each array element in the RIS array based on the obtained phase. The technical solution provided by the embodiments of the present invention realizes the phase quantization state of the array element of the unbinding RIS array by determining the discrete phase value of each array element in the RIS array according to the phase of each array element in the RIS array during each beam scanning, and configures different finite phase quantization values ​​for different RIS array adjustable units according to the requirements of different array elements. Under the premise of not increasing the number of RIS array quantization bits, not increasing the switch cost, and not increasing the control complexity, the phase of each array element of the RIS array is configured by relaxing the phase selectable range of the adjustable unit in the RIS array, thereby improving the beam control accuracy of the RIS array.

[0091] It should be understood that the discussion of any of the above embodiments is only exemplary and is not intended to imply that the scope of the present invention (including claims) is limited to these examples; under the idea of ​​the present invention, the technical features in the above embodiments or different embodiments may also be combined, the steps may be implemented in any order, and there are many other changes in different aspects of one or more embodiments of the present invention as described above, which are not provided in detail for the sake of simplicity. The above specific embodiments of the present invention are only used to illustrate or explain the principles of the present invention, and do not constitute a limitation of the present invention. Therefore, any modifications, equivalent substitutions, improvements, etc. made without departing from the spirit and scope of the present invention should be included in the scope of protection of the present invention. In addition, the claims attached to the present invention are intended to cover all changes and modifications that fall within the scope and boundaries of the attached claims, or the equivalent forms of such scope and boundaries.

Claims

1. An adjustable intelligent metasurface RIS array beamforming method, characterized in that: The method comprises: Traversing the scannable beam directions of the RIS array to perform beam scanning; Acquire the phase of each array element in the RIS array during each beam scan; Based on the acquired phase, a discrete phase value of each array element in the RIS array is determined, and the discrete phase value is used to determine the angle of RIS array beamforming.

2. The method according to claim 1, characterized in that The traversing the scannable beam direction of the RIS array to perform beam scanning includes: The beam weight of the RIS array is set to a low sidelobe weight, and beam scanning is performed based on the set weight.

3. The method according to claim 1, characterized in that The traversing the scannable beam direction of the RIS array to perform beam scanning includes: The scannable beam directions of the RIS array are traversed separately in at least two different dimensions.

4. The method according to claim 1, characterized in that: The determining of the discrete phase value of each array element in the RIS array includes determining the discrete phase value of each array element in the RIS array according to the following formula: The RIS array is an array of n-bit k×k array elements, where n is a positive integer and k is a natural number greater than or equal to 2; represents the discrete phase value of the target array element, i represents the number of discrete phase values, i=1,2,……,2 n ; represents the phase of the target array element obtained during beam scanning, j = 1, 2, ..., L, L represents the number of phases of the target array element obtained during beam scanning, m represents the array element number, m = 1, 2, ..., k 2 ; f() represents the clustering function.

5. The method according to any one of claims 1 to 4, characterized in that: The discrete phase value is used to determine the angle of RIS array beamforming, specifically: the phase of each array element in the RIS array is adjusted according to the determined discrete phase value to obtain the angle of RIS array beamforming.

6. The method according to claim 5, characterized in that The method further comprises: The adjusted RIS array is searched for beamforming weights.

7. The method according to claim 6, characterized in that The method further comprises: Generating a beamforming weight matrix of the RIS array according to the determined discrete phase values; The beamforming weight matrix is ​​stored.

8. A RIS array beamforming device, characterized in that: Includes memory, transceiver and processor: Memory for storing computer programs; a transceiver, for transmitting and receiving data under the control of the processor; A processor is configured to read the computer program in the memory and perform the following operations: Traversing the scannable beam directions of the RIS array to perform beam scanning; Acquire the phase of each array element in the RIS array during each beam scan; Based on the acquired phase, a discrete phase value of each array element in the RIS array is determined, and the discrete phase value is used to determine the angle of RIS array beamforming.

9. The device according to claim 8, characterized in that The traversing the scannable beam direction of the RIS array to perform beam scanning includes: The beam weight of the RIS array is set to a low sidelobe weight, and beam scanning is performed based on the set weight.

10. The device according to claim 8, characterized in that The traversing the scannable beam direction of the RIS array to perform beam scanning includes: The scannable beam directions of the RIS array are traversed separately in at least two different dimensions.

11. The device according to claim 8, characterized in that The determining of the discrete phase value of each array element in the RIS array includes determining the discrete phase value of each array element in the RIS array according to the following formula: The RIS array is an array of n-bit k×k array elements, where n is a positive integer and k is a natural number greater than or equal to 2; represents the discrete phase value of the target array element, i represents the number of discrete phase values, i=1,2,……,2 n ; represents the phase of the target array element obtained during beam scanning, j = 1, 2, ..., L, L represents the number of phases of the target array element obtained during beam scanning, m represents the array element number, m = 1, 2, ..., k 2 ; f() represents the clustering function.

12. The device according to any one of claims 8 to 11, characterized in that The discrete phase value is used to determine the angle of RIS array beamforming, specifically: The phase of each array element in the RIS array is adjusted according to the determined discrete phase value to obtain the angle of RIS array beamforming.

13. The device according to claim 12, characterized in that The processor also performs the following operations: The adjusted RIS array is searched for beamforming weights.

14. The device according to claim 12, characterized in that The processor also performs the following operations: Generating a beamforming weight matrix of the RIS array according to the determined discrete phase values; The beamforming weight matrix is ​​stored.

15. A RIS array beamforming device, characterized in that: The device comprises: A traversal unit, used for traversing the scannable beam directions of the RIS array to perform beam scanning; A phase acquisition unit, used to acquire the phase of each array element in the RIS array during each beam scanning; The discrete phase value determining unit is used to determine the discrete phase value of each array element in the RIS array based on the acquired phase, and the discrete phase value is used to determine the angle of RIS array beamforming.

16. A processor-readable storage medium, characterized in that: The processor-readable storage medium stores a program, and the program is used to enable the processor to execute the method according to any one of claims 1 to 7.

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