Method for designing tension of mesh antenna cable with proportional distribution of electrical parameters

Abstract

The invention discloses a net-shaped antenna cable tension design method based on electric parameter proportional distribution. The method comprises the following steps: 1, inputting a mesh antenna structure and electrical parameters into an initial model; 2, generating cable network structure node information according to the antenna structure parameters and the electrical parameters; 3, tension cable structure connection information is generated; step 4, calculating an amplitude distribution function of the aperture field according to electrical parameters including taper pin parameters and shape parameters of the aperture field; 5, according to the node information of the cable net structure, the connection information of the tension cable structure and the amplitude distribution function of the caliber field, generating a cable tension pre-distribution proportion; step 6, generating a cable tension distribution objective function according to the cable tension pre-distribution proportion; 7, establishing an optimization model and solving the optimization model; and step 8, outputting the optimized cable tension value. According to the invention, the electrical parameters of the reflector antenna are introduced into the tension design of the cable net structure, so that the rigidity distribution of the cable net structure of the mesh antenna oriented to the electrical performance and the excellent electrical performance can be realized.

Description

Technical Field

[0001] The invention belongs to the technical field of antennas, and in particular relates to a method for designing the wire tension of a mesh antenna with proportional distribution of electrical parameters. Background Art

[0002] Mesh antennas are gradually being used in space antenna design due to their light weight and small size. Mesh antennas use a cable net structure to support the parabola shape and use the laid metal wire mesh to receive and transmit electromagnetic waves. The design of the cable tension of the mesh antenna is the key to the antenna structure design, which ensures that the antenna reflector achieves the predetermined surface accuracy and electrical performance. How to design the cable tension and shape that meet the structural stiffness requirements is a key step in the design of the mesh antenna structure.

[0003] Nie et al. disclosed a tension optimization method considering the truss structure and the cable net system in the document “Optimization design method for mesh reflector antennas considering the truss deformation and thermal effects” (EngineeringStructures, 2020, 208: 112503), and designed for surface accuracy and tension uniformity. Zhang et al. disclosed a tension design method for cable-mesh reflector antennas considering interactive effects between cable network and supporting truss (EngineeringStructures, 2021, 244 (1): 112722) based on force density sensitivity. It was proposed to use force density sensitivity for tension optimization design, so as to achieve uniform tension and high surface accuracy design. These documents all take uniform tension as the design goal or constraint function, and strive to make the cable net system have a relatively uniform tension distribution. However, uniform tension distribution is not the optimal design state for electrical performance, and it is difficult to achieve better electrical performance. In the field of antenna structure design, the center area of ​​the antenna reflector requires high precision and has high electrical performance ratio requirements. Therefore, in the antenna structure design, a higher structural stiffness, that is, a larger tension, is often applied to the back frame structure in the center area of ​​the reflector to achieve better performance. Therefore, in response to the design requirements of mesh antenna line tension, a mesh antenna line tension design method with electrical parameter proportional distribution is proposed to achieve electrical performance-oriented mesh antenna line structural stiffness distribution and excellent electrical performance. Summary of the invention

[0004] In order to overcome the shortcomings of the above-mentioned prior art, the purpose of the present invention is to provide a mesh antenna cable tension design method with proportional distribution of electrical parameters. This method introduces the electrical parameters of the reflector antenna into the cable net structure tension design, which can achieve mesh antenna cable net structure stiffness distribution and excellent electrical performance oriented to electrical performance.

[0005] In order to achieve the above object, the technical solution adopted by the present invention is:

[0006] A method for designing the wire tension of a mesh antenna with proportional distribution of electrical parameters comprises the following steps;

[0007] Step 1: Input the mesh antenna structure and electrical parameters into the initial model;

[0008] Step 2: Generate cable network structure node information according to the antenna structure parameters and electrical parameters;

[0009] Step 3: Generate tension cable structure connection information according to the cable net structure node information;

[0010] Step 4: Calculate the aperture field amplitude distribution function based on the electrical parameters including the cone pin parameters and the aperture field shape parameters;

[0011] Step 5: Generate the cable tension pre-distribution ratio according to the cable net structure node information and the tension cable structure connection information and the aperture field amplitude distribution function;

[0012] Step 6: Generate a cable tension distribution objective function according to the cable tension pre-distribution ratio;

[0013] Step 7: According to the cable tension distribution objective function, establish an optimization model and solve it;

[0014] Step 8: Based on the established optimization model and solution results, output the optimized cable tension value.

[0015] The step 1 is specifically as follows:

[0016] The structural parameters include the mesh antenna aperture, focal length, offset distance, minimum distance between the front and rear mesh surfaces, cable unit cross-sectional area, Young's elastic modulus, cable net tension, and surface shape root mean square value;

[0017] The electrical parameters include cone pin parameters and aperture field shape parameters.

[0018] The step 2 is specifically as follows:

[0019] According to the mesh antenna aperture, focal length, offset distance, minimum distance between the front and rear mesh surfaces, cable unit cross-sectional area, Young's elastic modulus, cable net tension, and surface root mean square value structural parameters, the mesh antenna wire mesh structural node information is generated according to the following formula:

[0020]

[0021] ρ i -ρ j |≤l max

[0022] Among them, l max is the upper limit of the length of the node information constraint of the mesh antenna network structure, f is the antenna focal length, δ rms is the RMS value of the surface shape, ρ i , i They are respectively the adjacent i-th and j-th node information in the cable net structure, and || represents the norm operation.

[0023] The step 3 is specifically as follows:

[0024] According to the cable net structure node information, the tension cable structure connection information is generated according to the following formula:

[0025] l ij (ρ i ,ρ j )

[0026] Among them, l ij represents the connection information of the tensioned cable structure connecting the i-th and j-th nodes in the cable net structure, ρ i , i They are respectively the adjacent i-th and j-th node information in the cable net structure.

[0027] The step 4 is specifically as follows:

[0028] According to the electrical parameters including the cone pin parameters and the aperture field shape parameters, the aperture field amplitude distribution function is generated according to the following formula:

[0029]

[0030] Among them, Q(ρ) is the aperture field amplitude distribution function, ρ is the cable net structure node information, B is the cone pin parameter, P represents the aperture field shape parameter, and d is the aperture.

[0031] The step 5 is specifically as follows:

[0032] Generate the cable tension pre-distribution ratio according to the following formula:

[0033]

[0034] Among them, Q represents the pre-distribution ratio of cable tension, list() represents column vector operation, Q(l ij ) represents the aperture field amplitude distribution function at the cable connecting the i-th and j-th nodes, l ij represents the connection information of the tensioned cable structure connecting the i-th and j-th nodes in the cable net structure, ρ i It represents the information of the i-th node in the cable net structure, || represents the norm operation, B is the cone pin parameter, P represents the aperture field shape parameter, and d is the aperture.

[0035] The step 6 is specifically as follows:

[0036] The specific objective function of generating cable tension distribution is:

[0037]

[0038] Where f(X) represents the cable tension distribution objective function, X is the design variable, F is the cable tension, max(F) represents the maximum value of the cable tension, max() represents the maximum value operation, Q is the cable tension pre-distribution ratio, and || represents the norm operation.

[0039] The specific steps of optimizing the model and solving the problem in step 7 are as follows:

[0040] find X

[0041] min f(X)

[0042] stAF=0

[0043]

[0044] Where X is the design variable, f(X) represents the cable tension distribution objective function, F is the cable tension, and A is the equilibrium matrix generated by the cable net structure node information and the tension cable structure connection information. F are the upper and lower limits of cable tension respectively.

[0045] Beneficial effects of the present invention:

[0046] 1. The present invention takes into account the contribution of the electrical parameters of the mesh antenna to the structural stiffness, and directly designs the tension of the mesh antenna cable network structure oriented to the electrical performance, thereby achieving the electrical performance-oriented mesh antenna cable network structural stiffness distribution and excellent electrical performance;

[0047] 2. The present invention introduces electrical parameters into the structural design from the initial conceptual design stage, generates the cable tension pre-distribution ratio through the aperture field distribution, and the objective function makes the cable tension proportional to the aperture field amplitude function value, which can further ensure the rationality of the tension design of the mesh antenna cable network structure. The obtained result realizes the optimal structural design in terms of electrical performance. BRIEF DESCRIPTION OF THE DRAWINGS

[0048] Figure 1 It is a flow chart of the present invention.

[0049] Figure 2 The tension distribution result of the cable net structure obtained by the traditional uniform tension design method.

[0050] Figure 3 The tension distribution result of the cable net structure obtained by the method of the present invention is shown in FIG. DETAILED DESCRIPTION

[0051] The present invention will be further described in detail below in conjunction with the accompanying drawings.

[0052] like Figure 1 As shown, a method for designing the wire tension of a mesh antenna with proportional distribution of electrical parameters comprises the following steps;

[0053] Step 1, input the structural parameters provided by the user, including mesh antenna aperture, focal length, offset distance, minimum distance between front and rear mesh surfaces, cable unit cross-sectional area, Young's elastic modulus, cable net tension, and surface root mean square value, and electrical parameters including cone pin parameters and aperture field shape parameters;

[0054] Step 2: According to the mesh antenna aperture, focal length, offset distance, minimum distance between front and rear mesh surfaces, cable unit cross-sectional area, Young's elastic modulus, cable net tension, and surface root mean square value structural parameters, generate mesh antenna wire mesh structural node information according to the following cable length constraint formula; in terms of cable length and RMS accuracy, the longer the cable length, the greater the principle error;

[0055]

[0056] ρ i -ρ j |≤l max

[0057] Among them, l max is the upper limit of the length of the node information constraint of the mesh antenna network structure, f is the antenna focal length, δ rms is the RMS value of the surface shape, ρ i , i are the adjacent i-th and j-th node information in the cable network structure, respectively, and || represents the norm operation;

[0058] Step 3: Generate the tension cable structure connection information according to the following formula based on the cable net structure node information:

[0059] l ij (ρ i ,ρ j )

[0060] To provide support for the subsequent equilibrium matrix, the equilibrium matrix is ​​written in matrix form after establishing the cable force equilibrium equation through the cable net structure information.

[0061] Among them, l ij represents the connection information of the tensioned cable structure connecting the i-th and j-th nodes in the cable net structure, ρ i , i They are the adjacent i-th and j-th node information in the cable network structure respectively;

[0062] Step 4: Generate the aperture field amplitude distribution function according to the following formula based on the electrical parameters including the cone pin parameters and the aperture field shape parameters:

[0063]

[0064] Among them, Q(ρ) is the amplitude distribution function of the aperture field, ρ is the node information of the cable net structure, B is the cone pin parameter, P represents the aperture field shape parameter, and d is the aperture;

[0065] Step 5: Generate the cable tension pre-distribution ratio according to the following formula based on the cable net structure node information, the tension cable structure connection information, and the aperture field amplitude distribution function:

[0066]

[0067] Among them, Q represents the pre-distribution ratio of cable tension, list() represents column vector operation, Q(l ij ) represents the aperture field amplitude distribution function at the cable connecting the i-th and j-th nodes, l ij represents the connection information of the tensioned cable structure connecting the i-th and j-th nodes in the cable net structure, ρ i represents the i-th node information in the cable net structure, || represents the norm operation, B is the cone pin parameter, P represents the aperture field shape parameter, and d is the aperture;

[0068] Step 6: Generate the cable tension distribution objective function according to the cable tension pre-distribution ratio:

[0069]

[0070] Where f(X) represents the cable tension distribution objective function, X is the design variable, F is the cable tension, max(F) represents the maximum cable tension, max() represents the maximum value operation, Q represents the cable tension pre-distribution ratio, and || represents the norm operation;

[0071] Step 7: According to the cable tension distribution objective function, an optimization model is established and solved:

[0072] find X

[0073] min f(X)

[0074] stAF=0

[0075]

[0076] Where X is the design variable, f(X) represents the cable tension distribution objective function, F is the cable tension, and A is the equilibrium matrix generated by the cable net structure node information and the tension cable structure connection information. F They are the upper and lower limits of the cable tension respectively; the upper and lower limits are amplified by 5N calculated according to the traditional method, because the calculation result of the entire force balance structure is still a balanced structure after the overall amplification.

[0077] Step 8: Output the optimized cable tension value according to the established optimization model and solution results.

[0078] The advantages of the present invention can be further illustrated by the following simulation experiments:

[0079] 1. Simulation conditions:

[0080] The maximum projection aperture of the mesh antenna is 9.23m, the focal length is 6m, the offset height is 5m, and the minimum spacing between the front and rear mesh surfaces is 0.2m. The operating frequency is 2GHz, the cone pin parameter is -12dB, and the aperture field shape parameter is 1. The mesh surface of the mesh reflection surface is divided into 5 equal sections along the radial direction in the aperture surface. The Young's elastic modulus of the cable is E=20GPa, and the cable cross-sectional area is A=3.14mm2. The conventional tension uniform design method and the method of the present invention are used to design the cable tension of the mesh antenna.

[0081] 2. Simulation results:

[0082] The conventional tension uniform design method and the method of the present invention are used to design the tension of the mesh antenna line. The tension distribution results obtained by the conventional tension uniform design method are as follows: Figure 2 As shown, the tension design result obtained by the method of the present invention is as follows Figure 3 shown.

[0083] By comparison Figure 2 and Figure 3 It can be seen that the optimization result of uniform tension is obtained by using the traditional uniform tension design method, and the tension is 5N. The traditional tension design pursues the uniformity of force, so that the cable force tends to be consistent. This method changes the optimization objective function from the traditional uniform tension design to the distribution according to the proportion of electrical parameters. The method of the present invention obtains different tension distributions. In the overall trend, the tension in the center area is large and the tension in the edge area is small, thus providing a tension design scheme with good stiffness at the center of the reflector. From the perspective of ensuring electrical performance, the results obtained by the method of the present invention are more conducive to the realization of antenna electrical performance.

[0084] Because the central area of ​​the antenna contributes more to the overall electrical performance, the stiffness of the central area becomes higher as the force in the central area increases. High stiffness can better resist external factors, so it is beneficial to the realization of electrical performance.

[0085] At the same time, since the electrical parameters are introduced into the cable tension design, the obtained cable tension design result can achieve the optimal distribution of structural stiffness oriented to electrical performance. The simulation example verifies the effectiveness of the method of the present invention.

[0086] The parts not described in detail in this embodiment belong to the commonly known means in the industry and are not described here one by one. The above examples are only examples of the present invention and do not constitute a limitation on the protection scope of the present invention. All designs that are the same or similar to the present invention belong to the protection scope of the present invention.

Claims

1. A method for designing the wire tension of a mesh antenna with proportional distribution of electrical parameters, characterized in that: The steps include: Step 1: Input the mesh antenna structure and electrical parameters into the initial model; Step 2: Generate cable network structure node information according to the antenna structure parameters and electrical parameters; Step 3: Generate tension cable structure connection information according to the cable net structure node information; Step 4: Calculate the aperture field amplitude distribution function according to the electrical parameters; Step 5: Generate the cable tension pre-distribution ratio according to the cable net structure node information and the tension cable structure connection information and the aperture field amplitude distribution function; Step 6: Generate a cable tension distribution objective function according to the cable tension pre-distribution ratio; Step 7: According to the cable tension distribution objective function, establish an optimization model and solve it; Step 8: Based on the established optimization model and solution results, output the optimized cable tension value.

2. The method for designing the wire tension of a mesh antenna with electrical parameter proportional distribution according to claim 1, characterized in that: The step 1 is specifically as follows: The structural parameters include the mesh antenna aperture, focal length, offset distance, minimum distance between the front and rear mesh surfaces, cable unit cross-sectional area, Young's elastic modulus, cable net tension, and surface shape root mean square value; The electrical parameters include cone pin parameters and aperture field shape parameters.

3. The method for designing the wire tension of a mesh antenna with electrical parameter proportional distribution according to claim 2, characterized in that: The step 2 is specifically as follows: According to the mesh antenna aperture, focal length, offset distance, minimum distance between the front and rear mesh surfaces, cable unit cross-sectional area, Young's elastic modulus, cable net tension, and surface root mean square value structural parameters, the mesh antenna wire mesh structural node information is generated according to the following formula: r i -r j |≤l max Among them, l max is the upper limit of the length of the node information constraint of the mesh antenna network structure, f is the antenna focal length, δ rms is the RMS value of the surface shape, ρ i , i They are respectively the adjacent i-th and j-th node information in the cable net structure, and || represents the norm operation.

4. The method for designing the wire tension of a mesh antenna with electrical parameter proportional distribution according to claim 3, characterized in that: The step 3 is specifically as follows: According to the cable net structure node information, the tension cable structure connection information is generated according to the following formula: l ij (r i ,r j ) Among them, l ij represents the connection information of the tensioned cable structure connecting the i-th and j-th nodes in the cable net structure, ρ i , i They are respectively the adjacent i-th and j-th node information in the cable net structure.

5. The method for designing the wire tension of a mesh antenna with electrical parameter proportional distribution according to claim 4, characterized in that: The step 4 is specifically as follows: According to the electrical parameters including the cone pin parameters and the aperture field shape parameters, the aperture field amplitude distribution function is generated according to the following formula: Among them, Q(ρ) is the amplitude distribution function of the aperture field, ρ is the node information of the cable net structure, B is the cone pin parameter, P represents the aperture field shape parameter, and d is the aperture.

6. A method for designing the wire tension of a mesh antenna with electrical parameter proportional distribution according to claim 5, characterized in that: The step 5 is specifically as follows: Generate the cable tension pre-distribution ratio according to the following formula: Among them, Q represents the pre-distribution ratio of cable tension, list() represents column vector operation, Q(l ij ) represents the aperture field amplitude distribution function at the cable connecting the i-th and j-th nodes, l ij represents the connection information of the tensioned cable structure connecting the i-th and j-th nodes in the cable net structure, ρ i It represents the information of the i-th node in the cable net structure, || represents the norm operation, B is the cone pin parameter, P represents the aperture field shape parameter, and d is the aperture.

7. A method for designing the wire tension of a mesh antenna with electrical parameter proportional distribution according to claim 6, characterized in that: The step 6 is specifically as follows: The specific objective function of generating cable tension distribution is: Where f(X) represents the cable tension distribution objective function, X is the design variable, F is the cable tension, max(F) represents the maximum value of the cable tension, max() represents the maximum value operation, Q is the cable tension pre-distribution ratio, and || represents the norm operation.

8. The method for designing the wire tension of a mesh antenna with electrical parameter proportional distribution according to claim 7, characterized in that: The specific steps of optimizing the model and solving the problem in step 7 are as follows: find X min f(X) stAF=0 Where X is the design variable, f(X) represents the cable tension distribution objective function, F is the cable tension, and A is the equilibrium matrix generated by the cable net structure node information and the tension cable structure connection information. F are the upper and lower limits of cable tension respectively.

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