A rectenna array layout method and system

Abstract

The application discloses a rectenna array layout method and system, and the method comprises the following steps: establishing a rectangular coordinate system with the center of the rectenna array as the origin and determining the parameters required by the rectenna array layout; dividing the modular subarray area and determining the size specification set of the subarray unit filling each modular subarray area; setting the receiving power reference value set of the subarray unit; constructing the design variable representing the rectenna array layout scheme; comprehensively considering the subarray unit scale, the receiving power uniformity of the subarray unit and the matching of the receiving power of the subarray unit and the optimal radio frequency input power of the rectifier circuit, establishing the optimization model of the rectenna array layout, including the objective optimization function and the constraint condition; solving the optimization model of the rectenna array layout to obtain the optimal layout index, and outputting the optimal scheme of the rectenna array layout; the application has the advantages that the influencing factors are comprehensively considered, the layout scheme is optimized, and the rectenna linear array has good performance.

Description

Technical Field

[0001] This invention relates to the field of antenna design, and more specifically to a method and system for rectifier antenna array layout. Background Technology

[0002] Microwave wireless power transfer technology uses microwaves as an energy carrier to achieve long-distance directional transmission of electrical energy in free space. It can be used for wireless power supply in fields such as aerospace, space-based solar power stations, and the Internet of Things (IoT). According to the microwave transmission path, a microwave wireless power transfer system can be divided into a transmitter, free space, and a receiver. At the transmitter, the transmitting antenna radiates microwave energy in a specific frequency band in a directional manner. At the receiver, the receiving antenna, corresponding to the operating frequency band, collects the microwave energy within its aperture and transmits it to a rectifier circuit via a radio frequency synthesis network, converting it into DC power to supply the load. The receiving antenna and the rectifier circuit are collectively referred to as the rectifier antenna.

[0003] In microwave wireless power transmission systems, the receiving antenna aperture must be large enough to improve microwave collection capability and increase transmission distance. When the rectifier antenna is presented in the form of a large array, a hybrid array approach is generally adopted, i.e., RF combining is performed first, followed by DC combining. However, a large aperture leads to significant non-uniform power density distribution within the aperture, posing difficulties for both RF and DC combining. The size of the subarray elements, the uniformity of the received power of the subarray elements, and the matching between the received power of the subarray elements and the optimal RF input power of the rectifier circuit all affect the receiving efficiency of the rectifier antenna array and the difficulty of series-parallel DC combining. Therefore, these three factors should be comprehensively considered in the layout of the rectifier antenna array.

[0004] Chinese Patent Publication No. CN114171933A discloses a microwave rectifier antenna array method based on the cross-growth method. This method discretizes the energy model of the receiving antenna to obtain an energy matrix. Based on the energy matrix and the optimal input power of the rectifier circuit, the optimal number of subarrays in the microwave rectifier antenna array is determined. The cross-growth method is used to divide the microwave rectifier antenna array until the optimal number of subarrays is met or the total output power of the divided microwave rectifier antenna array meets the optimal output power range of the rectifier circuit. The array elements in each microwave rectifier antenna subarray are connected in a symmetrical layout. However, this method only considers the impact of the optimal input power of the rectifier circuit on the rectifier antenna, without comprehensively considering the impact of subarray element size, the uniformity of received power in subarray elements, and the matching of received power in subarray elements with the optimal RF input power of the rectifier circuit on the receiving efficiency of the rectifier antenna array and the difficulty of series-parallel DC-DC combining. Therefore, the layout of the rectifier antenna array is not optimized, and the performance of the rectifier antenna array is not good enough. Summary of the Invention

[0005] The technical problem to be solved by the present invention is that the existing layout methods for rectifier antenna arrays do not take into account all the influencing factors and the layout schemes are not optimized enough, resulting in poor performance of the rectifier antenna arrays.

[0006] This invention solves the above-mentioned technical problems through the following technical means: a method for arranging a rectifier antenna array, comprising the following steps:

[0007] Step a: Establish a rectangular coordinate system with the center of the rectified antenna array as the origin and determine the parameters required for the array layout;

[0008] Step b: Divide the modular subarray regions and determine the set of size specifications of the subarray elements that fill each modular subarray region;

[0009] Step c: Set the set of received power reference values ​​for the subarray elements;

[0010] Step d: Construct design variables to characterize the layout scheme of the rectified antenna array;

[0011] Step e: Taking into account the size of the subarray elements, the uniformity of the received power of the subarray elements, and the matching between the received power of the subarray elements and the optimal RF input power of the rectifier circuit, a dual-objective optimization model for the layout of the rectifier antenna array is established. The dual-objective optimization model includes the objective optimization function and the constraint conditions.

[0012] Step f: Solve the rectifier antenna array layout optimization model to obtain the optimal layout index and output the optimal layout scheme of the rectifier antenna array.

[0013] Furthermore, the parameters required for the layout of the rectifier antenna array in step a include:

[0014] The dimensions of the basic antenna array element, the square aperture size of the rectifier antenna array, the receiving efficiency of the basic antenna array element, the attenuation factor of the RF synthesis network, the power density distribution curve within the aperture of the rectifier antenna array, and the relationship curve between the rectification efficiency of the rectifier circuit and the RF input power.

[0015] Further, step b includes:

[0016] Using the x-axis and y-axis as axes of symmetry, the aperture of the rectifier antenna array is divided into 2n×2n modular subarray regions of equal area, each a square. The side length D / 2n of the modular subarray region is the side length D of the basic array element of the square antenna. a 2 d The value is 2d+1 times, where n and d are both positive integers; D is the side length of the square aperture of the rectified antenna array; there are 2d+1 possible sizes for the subarray elements, forming the set A of subarray element sizes, i.e., A = {2d+1}. a ×2 a |a=0,1,…,d}∪{2a-1 ×2 a |a=1,…,d}.

[0017] Further, step c includes:

[0018] The set of reference values ​​for the received power of the subarray unit is determined based on the relationship curve between the rectification efficiency of the rectifier circuit and the RF input power. As a reference for the received power selection of subarray elements at each location, among which This represents the k-th received power reference value, and m is the number of received power reference values ​​in this set.

[0019] Further, step d includes:

[0020] Construct design variable Q = {Q -n,-n Q -(n-1),-(n-1) ,…,Q i,j ,…,Q n-1,n-1 Q n,n} to characterize the layout scheme of the rectifier antenna array,

[0021] in,

[0022] ν i,j,k ={a i,j,k ,b i,j,k ,c i,j,k -n≤i≤n, -n≤j≤n, i≠0, j≠0, 1≤k≤s i,j

[0023] In the formula, Q represents the design variables of the rectifier antenna array layout; n represents the number of rows of modular subarray regions in the upper and lower half-planes of the rectifier antenna array or the number of columns of modular subarray regions in the left and right half-planes; Q i,j This represents the design variable for the modular subarray region located in the i-th row and j-th column, which is determined by s from the subarray element size specification set A. i,j Each subarray unit is filled; v i,j,k This represents the design variable for the k-th subarray element in the modular subarray region of row i and column j; a i,j,k This represents the size specification of the k-th subarray element in the modular subarray region of row i and column j; b i,j,k c represents the position coordinates of the k-th subarray element in the modular subarray region of row i and column j; i,j,k This indicates the perpendicular or parallel relationship between the long side of the k-th subarray element in the i-th row and j-th column modular subarray region and the x-axis: c i,j,k A value of 0 indicates that the longer side is perpendicular to the x-axis, c i,j,k A value of 1 indicates that the longer side is parallel to the x-axis.

[0024] Furthermore, the objective optimization function corresponding to the bi-objective optimization model in step e includes:

[0025] Through formula Determine the index that minimizes the received power nonuniformity of the rectified antenna array, where,

[0026] In the formula, ε i,j This represents the non-uniformity index of received power in the modular subarray region of row i and column j. This represents the received power reference value for all subarray elements in the modular subarray region at row i and column j. This represents the received power of the k-th subarray element in the modular subarray region of row i and column j, and... η a This represents the receiving efficiency of the basic antenna array element; r i,j,k σ represents the number of basic antenna array elements contained in the k-th subarray element of the modular subarray region in the i-th row and j-th column; μ0 represents the attenuation factor of the RF synthesis network; p(x,y) represents the power density at (x,y) within the aperture of the rectified antenna array; σ i,j,k This represents the set of coordinates of the region where the kth subarray element is located in the modular subarray region of the i-th row and j-th column;

[0027] Through formula Minimize the number of subarray elements in the rectified antenna array.

[0028] Furthermore, the constraints in step e include:

[0029]

[0030]

[0031]

[0032] In the formula, ∩ represents the intersection operation of sets; ∪ represents the union operation of sets; A represents the empty set; B represents the set of dimensions of the subarray elements; C represents the set of position coordinates of the subarray elements; C represents the graphical relationship between the long side of the subarray element and the x-axis, C = {0, 1}, where 0 indicates that the long side of the subarray element is perpendicular to the x-axis, and 1 indicates that the long side of the subarray element is parallel to the x-axis.

[0033] Furthermore, the optimal layout indices in step f include the number of subarray elements, the non-uniformity of received power, the total received power, the total received efficiency, and the average received power of the subarray elements.

[0034] Furthermore, the total received power of the optimal layout of the rectifier antenna array is obtained through the formula... Calculate, where, Let represent the optimal solution for the received power of the k-th subarray element in the modular subarray region of row i and column j. This represents the optimal solution for the number of subarray elements within the modular subarray region of row i and column j;

[0035] The overall receiving efficiency of the optimal layout of the rectifier antenna array is expressed by the formula. Calculate σ array This represents the set of coordinates for the region where the rectifier antenna array is located.

[0036] The average received power of subarray elements under the optimal layout scheme is calculated using the following formula.

[0037]

[0038] The present invention also provides a rectifier antenna array layout system, comprising:

[0039] The initialization module is used to establish a Cartesian coordinate system with the center of the rectifier antenna array as the origin and to determine the parameters required for the layout of the rectifier antenna array.

[0040] The region division module is used to divide modular subarray regions and determine the set of size specifications of the subarray elements that fill each modular subarray region.

[0041] The set setting module is used to set the set of received power reference values ​​for subarray elements;

[0042] The design variable construction module is used to construct design variables that characterize the layout scheme of the rectifier antenna array.

[0043] The optimization model construction module is used to comprehensively consider the size of the subarray elements, the uniformity of the received power of the subarray elements, and the matching between the received power of the subarray elements and the optimal RF input power of the rectifier circuit, and to establish a dual-objective optimization model for the layout of the rectifier antenna array. The dual-objective optimization model includes objective optimization functions and constraints.

[0044] The solver module is used to solve the rectifier antenna array layout optimization model to obtain the optimal layout index and output the optimal layout scheme of the rectifier antenna array.

[0045] Furthermore, the parameters required for the layout of the rectifier antenna array in the initialization module include:

[0046] The dimensions of the basic antenna array element, the square aperture size of the rectifier antenna array, the receiving efficiency of the basic antenna array element, the attenuation factor of the RF synthesis network, the power density distribution curve within the aperture of the rectifier antenna array, and the relationship curve between the rectification efficiency of the rectifier circuit and the RF input power.

[0047] Furthermore, the region division module is also used for:

[0048] Using the x-axis and y-axis as axes of symmetry, the aperture of the rectifier antenna array is divided into 2n×2n modular subarray regions of equal area, each a square. The side length D / 2n of the modular subarray region is the side length D of the basic array element of the square antenna. a 2 d The value is 2d+1 times, where n and d are both positive integers; D is the side length of the square aperture of the rectified antenna array; there are 2d+1 possible sizes for the subarray elements, forming the set A of subarray element sizes, i.e., A = {2d+1}. a ×2 a |a=0,1,…,d}∪{2 a-1 ×2 a |a=1,…,d}.

[0049] Furthermore, the set setting module is also used for:

[0050] The set of reference values ​​for the received power of the subarray unit is determined based on the relationship curve between the rectification efficiency of the rectifier circuit and the RF input power. As a reference for the received power selection of subarray elements at each location, among which This represents the k-th received power reference value, and m is the number of received power reference values ​​in this set.

[0051] Furthermore, the design variable construction module is also used for:

[0052] Construct design variable Q = {Q -n,-n Q -(n-1),-(n-1) ,…,Q i,j ,…,Q n-1,n-1 Q n,n} to characterize the layout scheme of the rectifier antenna array,

[0053]

[0054] ν i,j,k ={a i,j,k ,b i,j,k ,c i,j,k -n≤i≤n, -n≤j≤n, i≠0, j≠0, 1≤k≤s i,j

[0055] In the formula, Q represents the design variables of the rectifier antenna array layout; n represents the number of rows of modular subarray regions in the upper and lower half-planes of the rectifier antenna array or the number of columns of modular subarray regions in the left and right half-planes; Q i,j This represents the design variable for the modular subarray region located in the i-th row and j-th column, which is determined by s from the subarray element size specification set A. i,j Each subarray unit is filled; v i,j,kThis represents the design variable for the k-th subarray element in the modular subarray region of row i and column j; a i,j,k This represents the size specification of the k-th subarray element in the modular subarray region of row i and column j; b i,j,k c represents the position coordinates of the k-th subarray element in the modular subarray region of row i and column j; i,j,k This indicates the perpendicular or parallel relationship between the long side of the k-th subarray element in the i-th row and j-th column modular subarray region and the x-axis: c i,j,k A value of 0 indicates that the longer side is perpendicular to the x-axis, c i,j,k A value of 1 indicates that the longer side is parallel to the x-axis.

[0056] Furthermore, the objective optimization function corresponding to the bi-objective optimization model in the optimization model construction module includes:

[0057] Through formula Determine the index that minimizes the received power nonuniformity of the rectified antenna array, where,

[0058] In the formula, ε i,j This represents the non-uniformity index of received power in the modular subarray region of row i and column j. This represents the received power reference value for all subarray elements in the modular subarray region at row i and column j. This represents the received power of the k-th subarray element in the modular subarray region of row i and column j, and... η a This represents the receiving efficiency of the basic antenna array element; r i,j,k σ represents the number of basic antenna array elements contained in the k-th subarray element of the modular subarray region in the i-th row and j-th column; μ0 represents the attenuation factor of the RF synthesis network; p(x,y) represents the power density at (x,y) within the aperture of the rectified antenna array; σ i,j,k This represents the set of coordinates of the region where the kth subarray element is located in the modular subarray region of the i-th row and j-th column;

[0059] Through formula Minimize the number of subarray elements in the rectified antenna array.

[0060] Furthermore, the constraints in the optimization model construction module include:

[0061]

[0062]

[0063]

[0064] In the formula, ∩ represents the intersection operation of sets; ∪ represents the union operation of sets; A represents the empty set; B represents the set of subarray element size specifications; C represents the set of subarray element position coordinates; C represents the graphical relationship between the long side of the subarray element and the x-axis, C = {0, 1}, where 0 indicates that the long side of the subarray element is perpendicular to the x-axis, and 1 indicates that the long side of the subarray element is parallel to the x-axis.

[0065] Furthermore, the optimal layout indices in the solution module include the number of subarray elements, the non-uniformity of received power, the total received power, the total received efficiency, and the average received power of the subarray elements.

[0066] Furthermore, the total received power of the optimal layout of the rectifier antenna array is obtained through the formula... Calculate, where, Let represent the optimal solution for the received power of the k-th subarray element in the modular subarray region of row i and column j. This represents the optimal solution for the number of subarray elements within the modular subarray region of row i and column j;

[0067] The overall receiving efficiency of the optimal layout of the rectifier antenna array is expressed by the formula. Calculate σ array This represents the set of coordinates for the region where the rectifier antenna array is located.

[0068] The average received power of subarray elements under the optimal layout scheme is calculated using the following formula:

[0069]

[0070] The advantages of this invention are:

[0071] (1) This invention establishes a rectifier antenna array layout optimization model and considers the influence of various factors such as the size of subarray units, the uniformity of subarray unit received power, and the matching of subarray unit received power with the optimal RF input power of rectifier circuit on the layout of rectifier antenna array. Thus, a corresponding dual-objective optimization function and constraint conditions are constructed and solved to obtain the optimal layout index and output the optimal scheme of rectifier antenna array layout. This method considers all influencing factors and the layout of the rectifier antenna array has good performance.

[0072] (2) This invention establishes a dual-objective optimization function and constraints for the layout of the rectifier antenna array and solves them using a multi-objective hierarchical decision-making method. This results in a rectifier antenna array layout scheme with the minimum received power non-uniformity index, the minimum number of subarray units, and the matching of the received power of the subarray units with the optimal RF input power of the rectifier circuit. The minimum number of subarray units greatly reduces the number of rectifier circuits required for DC combining. The minimum received power non-uniformity index effectively reduces the difference in the input RF power of each rectifier circuit unit and reduces the difficulty of series-parallel DC combining. Thus, the overall scheme reduces the complexity and design difficulty of the overall system structure and is conducive to the series-parallel arraying of rectifier circuit units.

[0073] (3) Based on the relationship curve between the rectification efficiency of the rectifier circuit and the RF input power, the present invention determines the set of reference values ​​for the received power of the subarray unit, which can ensure that the RF combined output power of the subarray unit is located in the high-efficiency working area of ​​the rectifier circuit, thereby improving the rectification efficiency.

[0074] (4) The present invention divides the rectifier antenna array into several modular subarray regions of equal size and fills each modular subarray region with subarray units, which effectively reduces the complexity and design difficulty of the overall system structure and is conducive to solving the optimization model. Attached Figure Description

[0075] Figure 1 This is a flowchart of a rectifier antenna array layout method disclosed in an embodiment of the present invention;

[0076] Figure 2 This is a schematic diagram of the modular subarray region division in a rectifier antenna array layout method disclosed in an embodiment of the present invention;

[0077] Figure 3 The curve showing the relationship between the rectification efficiency of the rectification circuit and the radio frequency input power in a rectification antenna array layout method disclosed in an embodiment of the present invention is shown.

[0078] Figure 4 This is a visual representation of the rectifier antenna array layout scheme provided in the rectifier antenna array layout method disclosed in the embodiments of the present invention. Detailed Implementation

[0079] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below in conjunction with the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0080] Example 1

[0081] like Figure 1 As shown, the present invention provides a method for arranging a rectifier antenna array, comprising the following steps:

[0082] Step 1: The rectifier antenna array adopts a square aperture. A Cartesian coordinate system is established with the center of the rectifier antenna array as the origin, and the parameters required for the array layout are determined. The parameters required for the rectifier antenna array layout include:

[0083] (1) The size D of the basic array element of the square antenna a ×D a D a Indicates the side length;

[0084] (2) The square aperture size of the rectifier antenna array is D×D, where D represents the side length;

[0085] (3) The receiving efficiency η of the basic antenna array element a ;

[0086] (4) Attenuation factor μ0 of the radio frequency synthesis network;

[0087] (5) Power density distribution curve within the aperture of the rectified antenna array:

[0088]

[0089] In the formula, (x,y) represents the coordinates of any point within the aperture of the rectifier antenna array; p(x,y) represents the power density at (x,y) within the aperture of the rectifier antenna array; p max The maximum power density is represented at the center of the rectifier antenna array; α represents the power density distribution factor, which reflects the distribution characteristics of power density within the aperture of the rectifier antenna array. The power density within the aperture of the rectifier antenna array gradually decreases from the center to the edge, generally following a Gaussian distribution.

[0090] (6) The relationship curve between the rectification efficiency of the rectifier circuit and the RF input power.

[0091] Step 2: Divide the modular subarray regions; the specific process is as follows:

[0092] Using the x-axis and y-axis as axes of symmetry, the aperture of the rectifier antenna array is divided into 2n×2n square modular subarray regions of equal area, where n is a positive integer. The side length D / 2n of the modular subarray region is the side length D of the basic array element of the square antenna. a 2 d times, that is, 2 d =D / (2n·D) a During the design process, d is guaranteed to be a positive integer.

[0093] Step 3: Determine the set of size specifications for the subarray elements that fill each modular subarray region; the specific process is as follows:

[0094] There are 2d+1 possible sizes for the subarray elements, forming the set A of sizes for the subarray elements, i.e., A = {2d+1}. a ×2 a |a=0,1,…,d}∪{2 a-1 ×2 a |a=1,…,d}, where 2 0 ×2 0 The subarray element with the specified size is the smallest subarray element, also known as the basic antenna array element, 2 d ×2 d The subarray unit with the specified size is the largest subarray unit, which exactly covers the modular subarray area.

[0095] Step 4: Set the set of received power reference values ​​for the subarray elements; the specific process is as follows:

[0096] The set of reference values ​​for the received power of the subarray unit is determined based on the relationship curve between the rectification efficiency of the rectifier circuit and the RF input power. As a reference for the received power selection of subarray elements at each location, among which This represents the k-th received power reference value, and m is the number of received power reference values ​​in this set.

[0097] Based on the relationship curve between the rectification efficiency of the rectifier circuit and the RF input power, the set of reference values ​​for the received power of the subarray unit is determined. This ensures that the RF combined output power of the subarray unit is located in the high-efficiency operating region of the rectifier circuit, thereby improving the rectification efficiency.

[0098] Step 5: Construct design variables to characterize the layout scheme of the rectified antenna array; the relevant formulas are as follows:

[0099] Q = {Q -n,-n Q -(n-1),-(n-1) ,…,Q i,j ,…,Q n-1,n-1 Q n,n} (2)

[0100]

[0101] ν i,j,k ={a i,j,k ,b i,j,k ,c i,j,k -n≤i≤n, -n≤j≤n, i≠0, j≠0, 1≤k≤s i,j (4) In the formula,

[0102] Q represents the design variables for the layout of the rectifier antenna array; n represents the number of rows of modular subarray regions in the upper and lower half-planes or the number of columns of modular subarray regions in the left and right half-planes of the rectifier antenna array; Q i,j This represents the design variable for the modular subarray region located in the i-th row and j-th column, which is defined by s. i,j Each subarray element (all derived from the size specification set A of the subarray elements) is filled; v i,j,k This represents the design variable for the k-th subarray element in the modular subarray region of row i and column j; a i,j,k This represents the size specification of the k-th subarray element in the modular subarray region of row i and column j; b i,j,k c represents the position coordinates of the k-th subarray element in the modular subarray region of row i and column j; i,j,k This indicates the perpendicular or parallel relationship between the long side of the k-th subarray element in the i-th row and j-th column modular subarray region and the x-axis: c i,j,k A value of 0 indicates that the longer side is perpendicular to the x-axis, c i,j,k A value of 1 indicates that the longer side is parallel to the x-axis; a i,j,k b i,j,k and c i,j,k They collectively characterize the graphical properties of the k-th subarray element in the modular subarray region of row i and column j in the xoy plane.

[0103] Figure 2 This is a schematic diagram of the modular subarray region division of the rectifier antenna array in this invention. The rows above the x-axis are numbered sequentially with positive integers 1, 2, ..., n, and the rows below the x-axis are numbered sequentially with negative integers -1, -2, ..., -n. The columns to the right of the y-axis are numbered sequentially with positive integers 1, 2, ..., n, and the columns to the left of the y-axis are numbered sequentially with negative integers -1, -2, ..., -n.

[0104] Step 6: Considering the subarray element size, the uniformity of received power in the subarray elements, and the matching between the received power of the subarray elements and the optimal RF input power of the rectifier circuit, establish the bi-objective optimization function corresponding to the rectifier antenna array layout optimization model; the specific process is as follows:

[0105] (1) Minimize the received power non-uniformity index of the rectified antenna array

[0106]

[0107]

[0108] In the formula, ε represents the non-uniformity index of the received power of the rectified antenna array; ε i,j This represents the non-uniformity index of the received power in the modular subarray region of row i and column j; s i,j This represents the number of subarray elements within the modular subarray region in the i-th row and j-th column; This represents the received power reference value for all subarray elements in the modular subarray region at row ik and column j. Let represent the received power of the k-th subarray element in the modular subarray region of row i and column j, and

[0109]

[0110] In the formula, η a This represents the receiving efficiency of the basic antenna array element; r i,j,k σ represents the number of basic antenna array elements contained in the k-th subarray element of the modular subarray region in the i-th row and j-th column; μ0 represents the attenuation factor of the RF synthesis network; p(x,y) represents the power density at (x,y) within the aperture of the rectified antenna array; σ i,j,k This represents the set of coordinates of the region containing the k-th subarray element in the i-th row and j-th column of the modular subarray region.

[0111] The smaller the non-uniformity of the received power of the rectifier antenna array, the smaller the difference in received power among the subarray units, the smaller the difference in the output power of the RF synthesis of the subarray units, and the smaller the difference in the input RF power of the rectifier circuit units. Therefore, it is convenient to connect the rectifier circuit units in series and parallel to form an array.

[0112] (2) Minimize the number of subarray elements in the rectified antenna array

[0113]

[0114] In the formula, S represents the number of subarray elements of the rectified antenna array; s i,j This represents the number of subarray elements within the modular subarray region in the i-th row and j-th column.

[0115] The fewer the number of subarray units, the fewer rectifier circuit units are required for DC synthesis, thereby reducing the overall complexity and design difficulty of the system.

[0116] Step 7: Establish the constraints corresponding to the rectifier antenna array layout optimization model; the specific process is as follows:

[0117] (1) Geometric constraints of the rectifier antenna array layout optimization model:

[0118]

[0119] In the formula, ∩ represents the intersection operation of sets; ∪ represents the union operation of sets; Indicates the empty set; v i,j,kLet represent the design variable of the k-th subarray element in the modular subarray region of row i and column j; this formula means that the graphic of the k-th subarray element in the modular subarray region of row i and column j does not overlap with any other subarray elements in the region.

[0120] (2) Constraints on optimization variables in the rectifier antenna array layout optimization model, including the size specification a of the subarray elements. i,j,k The position coordinates of the subarray element b i,j,k The graphical relationship between subarray elements and the x-axis (c) i,j,k and subarray element received power reference value Constraints:

[0121]

[0122]

[0123] In the formula, A represents the set of dimensions of the subarray element; B represents the set of position coordinates of the subarray element; C represents the graphical relationship between the long side of the subarray element and the x-axis, C = {0, 1}, where 0 indicates that the long side of the subarray element is perpendicular to the x-axis, and 1 indicates that the long side of the subarray element is parallel to the x-axis; P ref It is a set of reference values ​​for the received power of subarray units selected based on the relationship curve between the rectification efficiency of the rectifier circuit and the RF input power; m is the set P ref The number of elements in the middle.

[0124] Step 8: Solve the above-mentioned rectifier antenna array layout optimization model through multi-objective hierarchical decision-making: First, solve the problem of minimizing the non-uniformity index of the received power of the rectifier antenna array. Then, while ensuring that the non-uniformity index is minimized, solve the problem of minimizing the number of subarray elements of the rectifier antenna array to obtain the optimal solution of the received power reference value of the subarray element in the i-th row and j-th column. The optimal solution Q for design variables * Thus, the optimal layout scheme of the rectifier antenna array is obtained:

[0125]

[0126]

[0127]

[0128] In the formula, the variable marked with an asterisk (*) in the upper right corner is the optimal solution for the corresponding variable in formulas (2)-(4); according to The optimal number of antenna basic array elements contained in the k-th subarray element of the modular subarray region in the i-th row and j-th column can be determined. The optimal value of the coordinate set of the region containing the kth subarray element in the i-th row and j-th column modular subarray region. Therefore, the optimal received power of the k-th subarray element in the modular subarray region of the i-th row and j-th column under the optimal layout can be calculated according to equation (15).

[0129]

[0130] Step 9: Calculate the optimal layout parameters of the rectified antenna array: number of subarray elements, received power non-uniformity, total received power, total receiving efficiency, and average received power of subarray elements, as detailed below.

[0131] The optimal number of subarray elements S in the layout of the rectifier antenna array * Calculate according to formula (16):

[0132]

[0133] Received power nonuniformity index ε * Calculate according to formula (17):

[0134]

[0135] In the formula, This represents the received power reference value of the subarray element in the i-th row and j-th column. The optimal solution.

[0136] Total Received Power of Optimal Layout of Rectifier Antenna Array Calculate according to formula (18):

[0137]

[0138] Overall receiving efficiency of optimal layout of rectifier antenna array Calculate according to formula (19):

[0139]

[0140] In the formula, σ represents the total received power of the optimal layout of the rectifier antenna array; p(x,y) represents the power density at (x,y) within the aperture of the rectifier antenna array; array This represents the set of coordinates for the region where the rectifier antenna array is located.

[0141] Average received power of subarray elements under optimal layout scheme Calculate according to formula (20):

[0142]

[0143] Step 10: Output the layout scheme of the rectifier antenna array and its intuitive display diagram.

[0144] The following simulation of a millimeter-wave rectified antenna array layout scheme operating at 94 GHz illustrates the layout steps and advantages of this invention. Millimeter waves are a band of microwaves approaching far-infrared wavelengths. The relevant content is as follows:

[0145] The basic antenna array element has a size of 2cm × 2cm, i.e., D a =2cm; the rectifier antenna array adopts a square aperture with dimensions of 1.92m × 1.92m, i.e., D = 1.92m; the receiving efficiency η of the basic antenna array element. a The attenuation factor μ0 of the RF synthesizing network is 0.3 dB; a rectangular coordinate system is established with the center of the rectifier antenna array aperture as the origin, and the received power density distribution curve within the rectifier antenna array aperture is shown below. That is, the maximum power density p at the center of the rectifier antenna array max 200W / m 2 The power density distribution factor α is 2.347; the relationship between the rectification efficiency of the rectifier circuit and the RF input power is shown in the curve. Figure 3 As shown.

[0146] (1) Divide the aperture of the rectifier antenna array into 12×12 square modular subarray regions of equal area, i.e., n=6. The side length of each modular subarray region is 16cm, which is 8 times the side length of the basic antenna array element, i.e., d=3. Therefore, there are 7 different sizes of subarray elements, forming a set A={2 0 ×2 0 ,2 1 ×2 1 ,2 2 ×2 2 ,2 3 ×2 3 ,2 0 ×2 1 ,2 1 ×2 2 ,2 2 ×2 3}

[0147] The rectified antenna array containing 9216 basic antenna array elements is divided into 144 modular subarray regions of equal size. Each modular subarray region is filled with subarray elements of 7 different sizes, which effectively reduces the complexity and design difficulty of the overall system structure and is conducive to solving the optimization model.

[0148] (2) Based on the relationship curve between the rectification efficiency of the rectifier circuit and the RF input power (e.g. Figure 3 (As shown) Determine the set of received power reference values ​​P for the subarray elements. ref={40,50,60}(mW) serves as a reference for the received power of subarray elements at each location. The received power reference values ​​in this set are within the high-efficiency operating range of the rectifier circuit, which is beneficial for obtaining higher rectification efficiency.

[0149] (3) Optimize the layout of the rectifier antenna array according to the optimization model and algorithm described above. A visual representation of the optimal layout scheme is shown in the figure below. Figure 4 As shown, the optimal layout of the rectified antenna array has 3348 subarray elements, a received power non-uniformity index of 0.1586, a total received power of 176.72W, a total receiving efficiency of 71.66%, an average received power of 56mW for each subarray element, and the received power of all subarray elements is between 35 and 80mW.

[0150] The optimized array layout achieves a received power non-uniformity index of 0.1586, effectively reducing the differences in input RF power among various rectifier circuit units and simplifying the series-parallel DC combining process. The number of subarray elements is 3348, significantly reduced compared to the 9216 elements in the basic antenna array, greatly decreasing the number of rectifier circuits required for DC combining. The received power of all subarray elements is between 35 and 80 mW, within the high-efficiency operating range of the rectifier circuits, ensuring high rectification efficiency for the rectifier circuit units in DC combining.

[0151] Through the above technical solutions, this invention overcomes the shortcomings of traditional methods that do not comprehensively consider the size of subarray units, the uniformity of subarray unit received power, and the matching of subarray unit received power with the optimal RF input power of the rectifier circuit. By establishing a dual-objective optimization model for the layout of the rectifier antenna array and solving it using a multi-objective hierarchical decision method, a rectifier antenna array layout scheme with the minimum received power non-uniformity index, the fewest number of subarray units, and the matching of subarray unit received power with the optimal RF input power of the rectifier circuit is obtained. This reduces the complexity and design difficulty of the overall system structure and is beneficial to the series and parallel arraying of rectifier circuit units. The specific effects are reflected in the following aspects: (1) Based on the relationship curve between the rectifier circuit efficiency and the RF input power, the set of reference values ​​for the received power of the subarray units is determined, which can ensure that the RF combined output power of the subarray units is located in the high-efficiency working area of ​​the rectifier circuit, thereby improving the rectification efficiency. (2) The rectifier antenna array is divided into several modular subarray regions of equal size, and each modular subarray region is filled with subarray units, which effectively reduces the complexity and design difficulty of the overall system structure and is beneficial to solving the optimization model. (3) A dual-objective optimization model for the layout of the rectifier antenna array was established and solved using a multi-objective hierarchical decision method. This has two major benefits: First, it minimizes the number of subarray units, thereby greatly reducing the number of rectifier circuits required for DC synthesis. Second, it minimizes the non-uniformity index of the received power of the rectifier antenna array, thereby effectively reducing the difference in input RF power of each rectifier circuit unit and reducing the difficulty of series-parallel DC synthesis.

[0152] Example 2

[0153] Based on Embodiment 1, Embodiment 2 of the present invention also provides a rectifier antenna array layout system, comprising:

[0154] The initialization module is used to establish a Cartesian coordinate system with the center of the rectifier antenna array as the origin and to determine the parameters required for the layout of the rectifier antenna array.

[0155] The region division module is used to divide modular subarray regions and determine the size of the subarray element that fills each modular subarray region;

[0156] The set setting module is used to set the set of received power reference values ​​for subarray elements;

[0157] The design variable construction module is used to construct design variables that characterize the layout scheme of the rectifier antenna array.

[0158] The optimization model construction module is used to comprehensively consider the size of the subarray elements, the uniformity of the received power of the subarray elements, and the matching between the received power of the subarray elements and the optimal RF input power of the rectifier circuit, and to establish a dual-objective optimization model for the layout of the rectifier antenna array. The dual-objective optimization model includes objective optimization functions and constraints.

[0159] The solver module is used to solve the rectifier antenna array layout optimization model to obtain the optimal layout index and output the optimal layout scheme of the rectifier antenna array.

[0160] Specifically, the parameters required for the layout of the rectifier antenna array in the initialization module include:

[0161] The dimensions of the basic antenna array element, the square aperture size of the rectifier antenna array, the receiving efficiency of the basic antenna array element, the attenuation factor of the RF synthesis network, the power density distribution curve within the aperture of the rectifier antenna array, and the relationship curve between the rectification efficiency of the rectifier circuit and the RF input power.

[0162] Specifically, the region division module is also used for:

[0163] Using the x-axis and y-axis as axes of symmetry, the aperture of the rectifier antenna array is divided into 2n×2n modular subarray regions of equal area, each a square. The side length D / 2n of the modular subarray region is the side length D of the basic array element of the square antenna. a 2 d The value is 2d+1 times, where n and d are both positive integers; D is the side length of the square aperture of the rectified antenna array; there are 2d+1 possible sizes for the subarray elements, forming the set A of subarray element sizes, i.e., A = {2d+1}. a ×2 a |a=0,1,…,d}∪{2 a-1 ×2 a |a=1,…,d}.

[0164] Specifically, the set setting module is also used for:

[0165] The set of reference values ​​for the received power of the subarray unit is determined based on the relationship curve between the rectification efficiency of the rectifier circuit and the RF input power. As a reference for the received power selection of subarray elements at each location, among which This represents the k-th received power reference value, and m is the number of received power reference values ​​in this set.

[0166] Specifically, the design variable construction module is also used for:

[0167] Construct design variable Q = {Q -n,-n Q -(n-1),-(n-1) ,…,Q i,j ,…,Q n-1,n-1 Q n,n} to characterize the layout scheme of the rectifier antenna array,

[0168] in,

[0169] ν i,j,k ={a i,j,k,b i,j,k ,c i,j,k -n≤i≤n, -n≤j≤n, i≠0, j≠0, 1≤k≤s i,j

[0170] In the formula, Q represents the design variables of the rectifier antenna array layout; n represents the number of rows of modular subarray regions in the upper and lower half-planes of the rectifier antenna array or the number of columns of modular subarray regions in the left and right half-planes; Q i,j This represents the design variable for the modular subarray region located in the i-th row and j-th column, which is determined by s from the subarray element size specification set A. i,j Each subarray unit is filled; v i,j,k This represents the design variable for the k-th subarray element in the modular subarray region of row i and column j; a i,j,k This represents the size specification of the k-th subarray element in the modular subarray region of row i and column j; b i,j,k c represents the position coordinates of the k-th subarray element in the modular subarray region of row i and column j; i,j,k This indicates the perpendicular or parallel relationship between the long side of the k-th subarray element in the i-th row and j-th column modular subarray region and the x-axis: c i,j,k A value of 0 indicates that the longer side is perpendicular to the x-axis, c i,j,k A value of 1 indicates that the longer side is parallel to the x-axis.

[0171] More specifically, the objective optimization function corresponding to the bi-objective optimization model in the optimization model construction module includes:

[0172] Through formula Determine the index that minimizes the received power nonuniformity of the rectified antenna array, where,

[0173] In the formula, ε i,j This represents the non-uniformity index of received power in the modular subarray region of row i and column j. This represents the received power reference value for all subarray elements in the modular subarray region at row i and column j. This represents the received power of the k-th subarray element in the modular subarray region of row i and column j, and... η a This represents the receiving efficiency of the basic antenna array element; r i,j,k σ represents the number of basic antenna array elements contained in the k-th subarray element of the modular subarray region in the i-th row and j-th column; μ0 represents the attenuation factor of the RF synthesis network; p(x,y) represents the power density at (x,y) within the aperture of the rectified antenna array; σ i,j,k This represents the set of coordinates of the region where the kth subarray element is located in the modular subarray region of the i-th row and j-th column;

[0174] Through formula Minimize the number of subarray elements in the rectified antenna array.

[0175] More specifically, the constraints in the optimization model construction module include:

[0176]

[0177]

[0178]

[0179] In the formula, ∩ represents the intersection operation of sets; ∪ represents the union operation of sets; A represents the empty set; B represents the set of dimensions of the subarray elements; C represents the set of position coordinates of the subarray elements; C represents the graphical relationship between the long side of the subarray element and the x-axis, C = {0, 1}, where 0 indicates that the long side of the subarray element is perpendicular to the x-axis, and 1 indicates that the long side of the subarray element is parallel to the x-axis.

[0180] More specifically, the optimal layout indices in the solution module include the number of subarray elements, the non-uniformity of received power, the total received power, the total received efficiency, and the average received power of the subarray elements.

[0181] More specifically, the total received power of the optimal layout of the rectifier antenna array is obtained through the formula... Calculate, where, Let represent the optimal solution for the received power of the k-th subarray element in the modular subarray region of row i and column j. This represents the optimal solution for the number of subarray elements within the modular subarray region of row i and column j;

[0182] The overall receiving efficiency of the optimal layout of the rectifier antenna array is expressed by the formula. Calculate σ array This represents the set of coordinates for the region where the rectifier antenna array is located.

[0183] The average received power of subarray elements under the optimal layout scheme is calculated using the following formula.

[0184]

[0185] The above embodiments are only used to illustrate the technical solutions of the present invention, and are not intended to limit it. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A method for arranging a rectified antenna array, characterized in that, Includes the following steps: Step a: Establish a rectangular coordinate system with the center of the rectified antenna array as the origin and determine the parameters required for the array layout; Step b: Divide the modular subarray regions and determine the set of size specifications of the subarray elements that fill each modular subarray region; Step c: Set the set of received power reference values ​​for the subarray elements; Step d: Construct design variables to characterize the layout scheme of the rectified antenna array; Step e: Taking into account the size of the subarray elements, the uniformity of the received power of the subarray elements, and the matching between the received power of the subarray elements and the optimal RF input power of the rectifier circuit, a dual-objective optimization model for the layout of the rectifier antenna array is established. The dual-objective optimization model includes the objective optimization function and the constraint conditions. The objective functions corresponding to the bi-objective optimization model include: Through formula Determine the index that minimizes the received power nonuniformity of the rectified antenna array, where, , This indicates the number of rows in the modular subarray region of the upper and lower half-planes of the rectified antenna array, or the number of columns in the modular subarray region of the left and right half-planes. Indicates the first line, number The non-uniformity index of received power in the modular subarray region; Indicates the first line, number The received power reference value for all subarray elements in the modular subarray region. ; Indicates the first line, number The first in the modular subarray region The received power of each subarray element and ; This indicates the receiving efficiency of the basic antenna array element; Indicates the first line, number The first modular subarray region The number of basic antenna array elements contained in a subarray element; This represents the attenuation factor of the radio frequency synthesis network; Indicates the aperture of the rectifier antenna array Power density at the location; Indicates the first line, number The first modular subarray region The set of coordinates of the region where each subarray element is located; Through formula Minimize the number of subarray elements in the rectified antenna array; The constraints include: In the formula, This represents the intersection operation of sets; This represents the union operation of sets; Indicates the empty set; This represents the set of dimensions and specifications for the subarray elements; Represents the set of position coordinates of subarray elements; Indicates the long side of the subarray element and The graphical relationship of the axes. 0 indicates that the longer side of the subarray element is parallel to the line segment. The axis is perpendicular, and 1 indicates that the long side of the subarray element is perpendicular to the axis. The axes are parallel; , , as well as They represent the first line, number The first in the modular subarray region Design variables, dimensions, location coordinates, and long side of each subarray element. The perpendicular or parallel relationship of the axes; Step f: Solve the rectifier antenna array layout optimization model to obtain the optimal layout index and output the optimal layout scheme of the rectifier antenna array.

2. The rectifier antenna array layout method according to claim 1, characterized in that, The parameters required for the layout of the rectified antenna array in step a include: The dimensions of the basic antenna array element, the square aperture size of the rectifier antenna array, the receiving efficiency of the basic antenna array element, the attenuation factor of the RF synthesis network, the power density distribution curve within the aperture of the rectifier antenna array, and the relationship curve between the rectification efficiency of the rectifier circuit and the RF input power.

3. The rectifier antenna array layout method according to claim 1, characterized in that, Step b includes: by shaft and The axis is the axis of symmetry, dividing the aperture of the rectifier antenna array into Modular subarray regions of equal area, each square, with a side length of [missing information]. It is the side length of the basic array element of a square antenna. of times, and All are positive integers; It is the side length of the square aperture of the rectified antenna array; the dimensions of the subarray elements are as follows: +1 type, a set of size specifications for the subarray elements. ,Right now .

4. The rectifier antenna array layout method according to claim 1, characterized in that, Step c includes: The set of reference values ​​for the received power of the subarray unit is determined based on the relationship curve between the rectification efficiency of the rectifier circuit and the RF input power. As a reference for the received power selection of subarray elements at each location, among which Indicates the first One received power reference value, This represents the number of received power reference values ​​in the set.

5. The rectifier antenna array layout method according to claim 1, characterized in that, Step d includes: Build design variables To characterize the array layout scheme of the rectifier antenna, in, In the formula, Design variables representing the layout of the rectifier antenna array; Indicates that it is located at the th line, number The design variables for the modular subarray region of the column, which are derived from the set of subarray element size specifications. of Each subarray unit is filled; A value of 0 indicates that the longer side is... The axis is perpendicular. A value of 1 indicates that the longer side is... The axes are parallel.

6. The rectifier antenna array layout method according to claim 1, characterized in that, The optimal layout indices in step f include the number of subarray elements, the non-uniformity of received power, the total received power, the total received efficiency, and the average received power of the subarray elements.

7. A method for arranging a rectified antenna array according to claim 6, characterized in that, The total received power of the optimal layout of the rectifier antenna array is expressed by the formula. Calculate, where, Indicates the first line, number The first modular subarray region The optimal solution for the received power of each subarray element. Indicates the first line, number The optimal solution for the number of subarray elements within a modular subarray region of a column; The overall receiving efficiency of the optimal layout of the rectifier antenna array is expressed by the formula. calculate, This represents the set of coordinates for the region where the rectifier antenna array is located. The average received power of subarray elements under the optimal layout scheme is calculated using the following formula. 。 8. A rectifier antenna array layout system, comprising the method described in any one of claims 1-7, characterized in that, include: The initialization module is used to establish a Cartesian coordinate system with the center of the rectifier antenna array as the origin and to determine the parameters required for the layout of the rectifier antenna array. The region division module is used to divide modular subarray regions and determine the size of the subarray element that fills each modular subarray region; The set setting module is used to set the set of received power reference values ​​for subarray elements; The design variable construction module is used to construct design variables that characterize the layout scheme of the rectifier antenna array. The optimization model construction module is used to comprehensively consider the size of the subarray element, the uniformity of the received power of the subarray element, and the matching between the received power of the subarray element and the optimal RF input power of the rectifier circuit, and to establish the dual-objective optimization function and constraints corresponding to the rectifier antenna array layout optimization model. The solver module is used to solve the rectifier antenna array layout optimization model to obtain the optimal layout index and output the optimal layout scheme of the rectifier antenna array.

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