Line impedance calculation method, system, equipment and medium of mesh shielding structure

Abstract

The present invention discloses a line impedance calculation method, system, equipment and medium for a mesh shielding structure. The method first calculates the signal leakage ratio of the mesh shielding layer relative to the signal transmission ratio of the electric formation based on the conductor width and spacing of the mesh shielding layer, then equates the signal leakage of the mesh shielding layer to the increase in the dielectric thickness of the dielectric layer, calculates the equivalent dielectric thickness based on the leakage ratio and the dielectric thickness parameter, and then calculates the equivalent dielectric constant of the mesh shielding structure compared to the large copper surface shielding layer based on the equivalence principle of the transmission time of the electric formation loop network. Finally, the line impedance of the mesh shielding structure is calculated by combining the line width, copper thickness, equivalent dielectric thickness, equivalent dielectric constant and the classic characteristic impedance calculation formula of the large copper surface shielding layer. The method proposes a calculation theory and calculation model for the line impedance of the mesh shielding structure for the first time, greatly improving the accuracy of the line impedance calculation of the mesh shielding structure, and can be well applied to the impedance line design of the mesh shielding structure.

Description

Technical Field

[0001] The present invention relates to the technical field of line impedance calculation, and in particular to a line impedance calculation method and system for a grid shielding structure, an electronic device, and a computer-readable storage medium. Background Art

[0002] With the rapid development of the communications industry, signal transmission speeds are getting faster and faster, and the requirements for operating frequencies and transmission quality are getting higher and higher. At the same time, the types and characteristics of high-speed transmission structures are increasing. In some special PCB boards and other carrier transmission characteristic impedance structures, the original large metal shielding layer structure is changed into a mesh shielding structure. In high-frequency signal transmission, high-frequency signal electromagnetic radiation is transmitted between the signal layer (i.e., the conductor layer) and the ground layer (i.e., the shielding layer). According to the classic characteristic impedance line transmission and TDR (time domain reflectometry) measurement rules, a high-frequency signal is emitted from the signal line. The signal is not only transmitted forward on the conductor, but also radiated to the ground plane. The induction signal received by the ground plane is returned to the measurement end (the measurement and transmission end share the same port). The line impedance value is calculated by the level strength of the transmitted signal and the reflected signal. Generally, the reflectivity is expressed as ρ = V reflected / V incident Indicates that the measured impedance Z = Z ref *(1+ρ) / (1-ρ) to measure, where ρ is the signal reflectivity, V reflected The level strength of the reflected received signal, V incident Indicates the level strength of the transmitted signal, Z ref Represents a standard reference resistance, typically 50 ohms. For large metal shield structures, signal reflection on the large copper surface follows a path consistent with the transmission cable length. Loss of reflected signal strength primarily stems from dielectric loss and conductor surface loss. Therefore, the aforementioned line impedance calculation method is well-suited for large metal shield structures.

[0003] However, for mesh shielding structures, after receiving the reflected signal through the mesh shielding layer with holes, it is affected by the distribution of electromagnetic signal lines and exhibits a uniform distribution in the local space. That is, dφ tends to be evenly distributed within a single square area (the grid size is a + b, where a represents the conductor width of the mesh shielding layer and b represents the spacing between conductors in the mesh shielding layer). Therefore, when the signal is transmitted to the shielding layer, part of it is received and returned by the shielding layer, while the other part is radiated and dissipated through the mesh holes, causing the return signal strength to vary, which in turn affects the impedance calculation. Therefore, existing line impedance calculation methods are not suitable for mesh shielding structures. Summary of the Invention

[0004] The present invention provides a line impedance calculation method and system for a mesh shielding structure, an electronic device, and a computer-readable storage medium to solve the technical problem that the existing line impedance value calculation method is not applicable to the mesh shielding structure.

[0005] According to one aspect of the present invention, a method for calculating line impedance of a mesh shielding structure is provided, comprising the following steps:

[0006] Obtaining the conductor width and spacing of the mesh shielding layer, and calculating the ratio of the signal leakage of the mesh shielding layer to the signal transmission amount of the electrical formation;

[0007] Obtain the dielectric thickness parameters of the dielectric layer, equate the signal leakage of the mesh shielding layer to an increase in dielectric thickness, and calculate the equivalent dielectric thickness based on the leakage ratio and dielectric thickness parameters;

[0008] Obtain the angle between the impedance line and the horizontal edge of the mesh shielding layer, the dielectric constant of the dielectric layer, and calculate the equivalent dielectric constant based on the time equivalence principle;

[0009] Obtain the line width and copper thickness of the impedance line, and calculate the line impedance by combining the equivalent dielectric thickness, equivalent dielectric constant, and the classic characteristic impedance calculation formula.

[0010] Furthermore, the escape ratio is calculated based on the following formula:

[0011]

[0012] Where η represents the dissipation ratio, a and b represent the conductor width and spacing of the mesh shield layer, respectively.

[0013] Furthermore, the equivalent dielectric thickness is calculated based on the following formula:

[0014]

[0015] Where h′ represents the equivalent dielectric thickness, h represents the dielectric thickness parameter of the dielectric layer, and η represents the dissipation ratio.

[0016] Furthermore, the process of calculating the equivalent dielectric constant based on the time equivalence principle is as follows:

[0017] In a single grid, the actual transmission time of the electrical signal is t = (1 + cosθ + sinθ)l / v, c represents the speed of light, ε r Represents the dielectric constant of the dielectric layer, θ represents the angle between the impedance line and the horizontal side of the grid shielding layer, l represents the length of the hypotenuse of a single grid, according to the time equivalence principle, assuming that the transmission length is still 2l, then ε′ r represents the equivalent dielectric constant, so

[0018] Furthermore, the line impedance of the mesh shielding structure is calculated based on the following formula:

[0019]

[0020] Where Z1 represents the line impedance, ε r represents the dielectric constant of the dielectric layer, a and b represent the conductor width and spacing of the mesh shield layer, respectively, θ represents the angle between the impedance line and the horizontal side of the mesh shield layer, w and t represent the line width and copper thickness of the impedance line, respectively.

[0021] Furthermore, the mesh shielding layer is infinitely wide relative to the impedance line in the width direction; or, the mesh shielding layer is larger than one side of the impedance line by more than 3 mm in the width direction.

[0022] In addition, the present invention also provides a line impedance calculation system for a grid shielding structure, comprising:

[0023] The first calculation module is used to obtain the conductor width and spacing of the grid shielding layer, and calculate the leakage ratio of the signal leakage of the grid shielding layer to the signal transmission amount of the electrical formation;

[0024] The second calculation module is used to obtain the dielectric thickness parameter of the dielectric layer, equate the signal leakage of the grid shielding layer to the increase in dielectric thickness, and calculate the equivalent dielectric thickness based on the leakage ratio and the dielectric thickness parameter;

[0025] The third calculation module obtains the angle between the impedance line and the horizontal edge of the mesh shielding layer, the dielectric constant of the dielectric layer, and calculates the equivalent dielectric constant based on the time equivalence principle;

[0026] The fourth calculation module is used to obtain the line width and copper thickness of the impedance line, and calculate the line impedance by combining the equivalent dielectric thickness, equivalent dielectric constant and the classic characteristic impedance calculation formula.

[0027] Furthermore, the fourth calculation module calculates the line impedance of the mesh shielding structure based on the following formula:

[0028]

[0029] Where Z1 represents the line impedance, ε r represents the dielectric constant of the dielectric layer, a and b represent the conductor width and spacing of the mesh shield layer, respectively, θ represents the angle between the impedance line and the horizontal side of the mesh shield layer, w and t represent the line width and copper thickness of the impedance line, respectively.

[0030] In addition, the present invention also provides an electronic device, including a processor and a memory, wherein the memory stores a computer program, and the processor is configured to execute the steps of the above method by calling the computer program stored in the memory.

[0031] In addition, the present invention also provides a computer-readable storage medium for storing a computer program for calculating the line impedance of a mesh shielding structure, wherein the computer program executes the steps of the above-mentioned method when running on a computer.

[0032] The present invention has the following effects:

[0033] The line impedance calculation method of the mesh shielding structure of the present invention takes into account that after the signal is transmitted to the mesh shielding layer, a part of the signal is received and returned by the mesh shielding layer, while the other part is radiated out through the mesh holes of the mesh shielding layer and dissipated, which causes the return signal strength to change, thereby affecting the accuracy of the impedance value calculation. Therefore, the present invention first calculates the signal dissipation ratio of the mesh shielding layer relative to the signal transmission amount of the electric formation based on the conductor width and spacing of the mesh shielding layer, and then equates the signal dissipation of the mesh shielding layer to the increase in the dielectric thickness of the dielectric layer, thereby calculating the equivalent dielectric thickness based on the dissipation ratio and the dielectric thickness parameter, and then calculates the equivalent dielectric constant of the mesh shielding structure compared to the large copper surface shielding layer based on the equivalent principle of the transmission time of the electric formation loop network. Finally, the line impedance of the mesh shielding structure is calculated by combining the line width, copper thickness, equivalent dielectric thickness, equivalent dielectric constant and the classic characteristic impedance calculation formula of the large copper surface shielding layer. This invention proposes for the first time a calculation theory and calculation model for the line impedance of a mesh shielding structure, taking into account the influence of the dissipation effect of the mesh shielding layer on the impedance calculation. By equating the signal dissipation of the mesh shielding layer to an increase in dielectric thickness, and calculating the equivalent dielectric constant of the mesh shielding structure compared to the large copper surface shielding layer based on the time equivalence principle, the accuracy of the line impedance calculation of the mesh shielding structure is greatly improved, and it can be well applied to the impedance line design of the mesh shielding structure.

[0034] In addition, the line impedance calculation system, electronic device, and computer-readable storage medium of the grid shielding structure of the present invention also have the above advantages.

[0035] In addition to the above-described objects, features and advantages, the present invention has other objects, features and advantages. The present invention will be further described in detail below with reference to the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0036] The accompanying drawings, which constitute part of this application, are intended to provide a further understanding of the present invention. The exemplary embodiments of the present invention and their descriptions are intended to explain the present invention and do not constitute an undue limitation of the present invention. In the accompanying drawings:

[0037] Figure 1 It is a schematic cross-sectional structural diagram of a grid shielding structure according to a preferred embodiment of the present invention.

[0038] Figure 2 It is a schematic diagram of a preferred embodiment of the present invention in which the impedance line is arranged at an angle to the horizontal side of the mesh shielding layer.

[0039] Figure 3 It is a flow chart of a method for calculating line impedance of a grid shielding structure according to a preferred embodiment of the present invention.

[0040] Figure 4 It is a schematic diagram of the module structure of a line impedance calculation system of a grid shielding structure according to another embodiment of the present invention. DETAILED DESCRIPTION

[0041] The embodiments of the present invention are described in detail below with reference to the accompanying drawings. However, the present invention can be implemented in many different ways as defined and covered below.

[0042] It can be understood that the preferred embodiment of the present invention provides a method for calculating the line impedance of a mesh shielding structure, wherein, Figure 1 and Figure 2 As shown, the impedance line structure with a grid shielding structure specifically includes a wiring layer, a dielectric layer and a grid shielding layer. The wiring layer and the grid shielding layer are respectively arranged on both sides of the dielectric layer. The wiring layer is designed with an impedance line, which is generally a single-ended microstrip line. The grid shielding layer is an orthogonal grid conductor. Optionally, the grid shielding layer is infinitely wide relative to the impedance line in the width direction; or, the grid shielding layer is more than 3mm larger than the impedance line on one side in the width direction. Figure 3 As shown, the line impedance calculation method of the grid shielding structure specifically includes the following contents:

[0043] Step S1: obtaining the conductor width and spacing of the mesh shielding layer, and calculating the signal leakage ratio of the mesh shielding layer to the signal transmission amount of the electrical formation;

[0044] Step S2: Obtain the dielectric thickness parameter of the dielectric layer, equate the signal leakage of the mesh shielding layer to the increase in dielectric thickness, and calculate the equivalent dielectric thickness based on the leakage ratio and the dielectric thickness parameter;

[0045] Step S3: Obtain the angle between the impedance line and the horizontal side of the mesh shielding layer, and the dielectric constant of the dielectric layer, and calculate the equivalent dielectric constant based on the time equivalence principle;

[0046] Step S4: Obtain the line width and copper thickness of the impedance line, and calculate the line impedance by combining the equivalent dielectric thickness, equivalent dielectric constant and the classic characteristic impedance calculation formula.

[0047] It can be understood that the line impedance calculation method of the mesh shielding structure of this embodiment takes into account that after the signal is transmitted to the mesh shielding layer, a part of the signal is received and returned by the mesh shielding layer, while the other part is radiated out through the mesh holes of the mesh shielding layer and dissipated, which causes the return signal strength to change, thereby affecting the accuracy of the impedance value calculation. Therefore, the present invention first calculates the signal dissipation ratio of the mesh shielding layer relative to the signal transmission amount of the electric formation based on the conductor width and spacing of the mesh shielding layer, and then equates the signal dissipation of the mesh shielding layer to the increase in the dielectric thickness of the dielectric layer, thereby calculating the equivalent dielectric thickness based on the dissipation ratio and the dielectric thickness parameter, and then calculates the equivalent dielectric constant of the mesh shielding structure compared to the large copper surface shielding layer based on the equivalence principle of the transmission time of the electric formation loop network. Finally, the line impedance of the mesh shielding structure is calculated by combining the line width, copper thickness, equivalent dielectric thickness, equivalent dielectric constant and the classic characteristic impedance calculation formula of the large copper surface shielding layer. This invention proposes for the first time a calculation theory and calculation model for the line impedance of a mesh shielding structure, taking into account the influence of the dissipation effect of the mesh shielding layer on the impedance calculation. By equating the signal dissipation of the mesh shielding layer to an increase in dielectric thickness, and calculating the equivalent dielectric constant of the mesh shielding structure compared to the large copper surface shielding layer based on the time equivalence principle, the accuracy of the line impedance calculation of the mesh shielding structure is greatly improved, and it can be well applied to the impedance line design of the mesh shielding structure.

[0048] It can be understood that in step S1, since the electromagnetic signal line is uniformly distributed in a single grid area (i.e., a grid size of a+b) in the grid shielding layer, after the signal is transmitted to the grid shielding layer, the actual signal leakage amount in the single grid area relative to the signal transmission amount is proportional to the receiving area, that is, Among them, φ1 and φ 总 Represent the signal dissipation and signal transmission respectively, S1 and S 总 Represent the mesh hole area and total area within a single mesh area, respectively. a and b represent the conductor width and spacing of the mesh shield layer, respectively. Therefore, only the conductor width a and spacing b of the mesh shield layer need to be input to calculate the dissipation ratio based on the following formula:

[0049]

[0050] Here, η represents the escape ratio.

[0051] It can be understood that in step S2, according to the classic characteristic impedance calculation formula of the large copper surface shielding layer: It can be seen that the line impedance Z0 is related to the line width w of the impedance line, the copper thickness t, and the dielectric constant ε of the dielectric layer. rIt is inversely proportional to the dielectric thickness h, and directly proportional to it. The greater the dielectric thickness h, the less signal is received. The signal reception is directly related to the electrical-ground layer spacing (i.e., the distance from the dielectric layer to the mesh shielding layer). Increasing the mesh is equivalent to increasing the electrical-ground layer spacing. Therefore, after replacing the large copper surface shielding layer with a mesh shielding layer, the signal radiation emission can be equivalent to an increase in dielectric thickness. Therefore, by inputting the dielectric thickness parameter of the dielectric layer, the equivalent dielectric thickness can be calculated based on the following formula:

[0052]

[0053] Where h′ represents the equivalent dielectric thickness, h represents the dielectric thickness parameter of the dielectric layer, and η represents the dissipation ratio.

[0054] It can be understood that in step S3, from the perspective of the electrical formation loop, the characteristic impedance transmission cable still presents a straight line in the dielectric layer, but the transmission path of the mesh shielding layer is affected by the angle between the transmission line and the mesh. Specifically, in a single grid, the signal is transmitted along the right-angled side of the single grid. According to the relationship between the hypotenuse and the short side of the right triangle, the signal transmission length of the mesh shielding layer is: l(cosθ+sinθ), where θ represents the angle between the impedance line and the horizontal side of the mesh shielding layer, and l represents the length of the hypotenuse of the right triangle. Combined with the transmission speed of the electrical signal in the medium, it is: c represents the speed of light, ε r = represents the dielectric constant of the dielectric layer. Therefore, the actual transmission time of the electrical signal is t = (1 + cosθ + sinθ) l / v. According to the transmission time equivalence principle of the electrical formation loop network, assuming that the transmission length is still 2l, then ε′ r represents the equivalent dielectric constant, which can be calculated as follows:

[0055] It can be understood that in step S4, the line width w and copper thickness t of the impedance line are obtained, and combined with the equivalent dielectric thickness h' and equivalent dielectric constant ε' calculated previously r The classic characteristic impedance calculation formula of the large copper surface shielding layer structure is modified to obtain the line impedance calculation formula of the mesh shielding structure:

[0056]

[0057] Where Z1 represents the line impedance of the mesh shielding structure, ε r represents the dielectric constant of the dielectric layer, a and b represent the conductor width and spacing of the mesh shield layer, respectively, θ represents the angle between the impedance line and the horizontal side of the mesh shield layer, w and t represent the line width and copper thickness of the impedance line, respectively.

[0058] It can be understood that in order to verify the calculation accuracy of the line impedance calculation model of the mesh shielding structure of the present invention, actual verification was carried out, and the specific verification case is as follows.

[0059] Case 1: Set up a double-sided board, according to the outer microstrip line stacking structure, the line layer design line width is 120um, the transmission cable copper thickness is 50um, the dielectric layer material (FR4, epoxy resin) has a dielectric constant Dk of 4.4, the dielectric thickness is 89um, the conductor width a of the mesh shielding layer is 1000um, the spacing b is 1000um, and the angles between the transmission line and the horizontal direction of the mesh are 0°, 15°, 30°, 45°, 60°, and 90°, respectively. The actual measured impedance values ​​simulated by the calculation model are shown in Table 1 below.

[0060] Table 1. Comparison of impedance values ​​at different angles

[0061] w / um t / um h / um Dk θ / ° a b Z-estimation Z measured Remark 120 50 89 4.4 0 1000 0 46.69 48.32 Conventional large copper surface impedance 120 50 89 4.4 0 1000 1000 57.07 58.84 120 50 89 4.4 15 1000 1000 52.547 52.89 120 50 89 4.4 30 1000 1000 50.01 51.35 120 50 89 4.4 45 1000 1000 49.19 49.58 120 50 89 4.4 60 1000 1000 50.00 50.89 120 50 89 4.4 90 1000 1000 57.05 57.35

[0062] Case 2: A double-sided board is set up with an outer microstrip line stacking structure. The line layer is designed to have a line width of 240 μm, a copper thickness of 50 μm, a dielectric constant Dk of 4.4, and a thickness of 89 μm for the dielectric layer material (FR4, epoxy resin). The conductor width a of the mesh shielding layer is 1000 μm, and the spacing b is 1000 μm, 2000 μm, 3000 μm, and 4000 μm, respectively. The angle between the transmission line and the horizontal direction of the mesh is 0°. The actual measured impedance values ​​simulated by the calculation model are shown in Table 2 below.

[0063] Table 2. Effect of different mesh shielding layer spacing on impedance value

[0064] w / um t / um h / um Dk θ / ° a b Z-estimation Z measured 240 50 89 4.4 0 1000 1000 38.83 40.26 240 50 89 4.4 0 1000 2000 49.66 50.21 240 50 89 4.4 0 1000 3000 58.28 59.39 240 50 89 4.4 0 1000 4000 65.32 63.89

[0065] It can be seen from the above practical verification results that the calculation accuracy of the line impedance calculation model of the mesh shielding structure of the present invention is very high.

[0066] In addition, if Figure 4 Another embodiment of the present invention further provides a line impedance calculation system for a mesh shielding structure, preferably using the line impedance calculation method described above, the system comprising:

[0067] The first calculation module is used to obtain the conductor width and spacing of the grid shielding layer, and calculate the leakage ratio of the signal leakage of the grid shielding layer to the signal transmission amount of the electrical formation;

[0068] The second calculation module is used to obtain the dielectric thickness parameter of the dielectric layer, equate the signal leakage of the grid shielding layer to the increase in dielectric thickness, and calculate the equivalent dielectric thickness based on the leakage ratio and the dielectric thickness parameter;

[0069] The third calculation module obtains the angle between the impedance line and the horizontal edge of the mesh shielding layer, the dielectric constant of the dielectric layer, and calculates the equivalent dielectric constant based on the time equivalence principle;

[0070] The fourth calculation module is used to obtain the line width and copper thickness of the impedance line, and calculate the line impedance by combining the equivalent dielectric thickness, equivalent dielectric constant and the classic characteristic impedance calculation formula.

[0071] It can be understood that the line impedance calculation system of the mesh shielding structure of this embodiment takes into account that after the signal is transmitted to the mesh shielding layer, part of the signal is received and returned by the mesh shielding layer, while the other part is radiated out through the mesh holes of the mesh shielding layer and dissipated, which causes the return signal strength to change, thereby affecting the accuracy of the impedance value calculation. Therefore, the present invention first calculates the signal dissipation ratio of the mesh shielding layer relative to the signal transmission amount of the electrical formation based on the conductor width and spacing of the mesh shielding layer, and then equates the signal dissipation of the mesh shielding layer to the increase in the dielectric thickness of the dielectric layer, thereby calculating the equivalent dielectric thickness based on the dissipation ratio and the dielectric thickness parameter, and then calculates the equivalent dielectric constant of the mesh shielding structure compared to the large copper surface shielding layer based on the time equivalence principle. Finally, the line impedance of the mesh shielding structure is calculated by combining the line width, copper thickness, equivalent dielectric thickness, equivalent dielectric constant and the classic characteristic impedance calculation formula of the large copper surface shielding layer. This invention proposes for the first time a calculation theory and calculation model for the line impedance of a mesh shielding structure, taking into account the influence of the dissipation effect of the mesh shielding layer on the impedance calculation. By equating the signal dissipation of the mesh shielding layer to an increase in dielectric thickness, and calculating the equivalent dielectric constant of the mesh shielding structure compared to the large copper surface shielding layer based on the time equivalence principle, the accuracy of the line impedance calculation of the mesh shielding structure is greatly improved, and it can be well applied to the impedance line design of the mesh shielding structure.

[0072] It can be understood that the first calculation module calculates the dissipation ratio based on the following formula:

[0073]

[0074] Where η represents the dissipation ratio, a and b represent the conductor width and spacing of the mesh shield layer, respectively.

[0075] It can be understood that the second calculation module calculates the equivalent dielectric thickness based on the following formula:

[0076]

[0077] Where h′ represents the equivalent dielectric thickness, h represents the dielectric thickness parameter of the dielectric layer, and η represents the dissipation ratio.

[0078] It can be understood that the third calculation module calculates the equivalent dielectric constant based on the following formula:

[0079]

[0080] Among them, ε′ r represents the equivalent dielectric constant, ε r represents the dielectric constant of the dielectric layer, and θ represents the angle between the impedance line and the horizontal side of the mesh shielding layer.

[0081] It can be understood that the fourth calculation module calculates the line impedance of the mesh shielding structure based on the following formula:

[0082]

[0083] Where Z1 represents the line impedance, ε r represents the dielectric constant of the dielectric layer, a and b represent the conductor width and spacing of the mesh shield layer, respectively, θ represents the angle between the impedance line and the horizontal side of the mesh shield layer, w and t represent the line width and copper thickness of the impedance line, respectively.

[0084] It can be understood that each module in the system of this embodiment corresponds to each step of the above method embodiment, so the specific calculation principle of each module will not be repeated here, and reference can be made to the above method embodiment.

[0085] In addition, another embodiment of the present invention further provides an electronic device, including a processor and a memory, wherein the memory stores a computer program, and the processor is configured to execute the steps of the above method by calling the computer program stored in the memory.

[0086] In addition, another embodiment of the present invention further provides a computer-readable storage medium for storing a computer program for calculating the line impedance of a mesh shielding structure. When the computer program is run on a computer, the steps of the method described above are executed.

[0087] Common computer-readable storage media include: floppy disks, flexible disks, hard disks, magnetic tape, any other magnetic media, CD-ROMs, any other optical media, punch cards, paper tape, any other physical medium with a pattern of holes, random access memory (RAM), programmable read-only memory (PROM), erasable programmable read-only memory (EPROM), flash-erasable programmable read-only memory (FLASH-EPROM), any other memory chip or cartridge, or any other medium that can be read by a computer. Instructions can further be transmitted or received via a transmission medium. The term transmission medium includes any tangible or intangible medium that can be used to store, encode, or carry instructions for execution by a machine, and includes digital or analog communication signals or other intangible media that facilitate communication of such instructions. Transmission media include coaxial cables, copper wire, and fiber optics, including the wires of a bus used to transmit a computer data signal.

[0088] The foregoing description is merely a preferred embodiment of the present invention and is not intended to limit the present invention. Those skilled in the art will readily appreciate that various modifications and variations of the present invention are possible. Any modifications, equivalent substitutions, or improvements made within the spirit and principles of the present invention are intended to be within the scope of protection of the present invention.

[0089] Those skilled in the art will appreciate that the embodiments of the present application can be provided as methods, systems, or computer program products. Therefore, the application can adopt the form of a complete hardware embodiment, a complete software embodiment, or an embodiment in combination with software and hardware. Moreover, the application can adopt the form of a computer program product implemented on one or more computer-usable storage media (including but not limited to disk storage, CD-ROM, optical storage, etc.) that contain computer-usable program code. The scheme in the embodiment of the present application can be implemented in various computer languages, for example, object-oriented programming language Java and literal translation scripting language JavaScript, etc.

[0090] The present application is described with reference to the flowcharts and / or block diagrams of the methods, devices (systems), and computer program products according to the embodiments of the present application. It should be understood that each process and / or box in the flowchart and / or block diagram, as well as the combination of the processes and / or boxes in the flowchart and / or block diagram, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, a special-purpose computer, an embedded processor, or other programmable data processing device to produce a machine, so that the instructions executed by the processor of the computer or other programmable data processing device generate instructions for implementing the steps in the process. Figure 1a process or multiple processes and / or boxes Figure 1 A device that provides the functions specified in a block or multiple blocks.

[0091] These computer program instructions may also be stored in a computer readable memory that can direct a computer or other programmable data processing device to work in a specific manner, so that the instructions stored in the computer readable memory produce an article of manufacture comprising an instruction device, which implements the process Figure 1 a process or multiple processes and / or boxes Figure 1 The function specified in one or more boxes.

[0092] These computer program instructions can also be loaded onto a computer or other programmable data processing device so that a series of operational steps are executed on the computer or other programmable device to produce a computer-implemented process, thereby providing the instructions executed on the computer or other programmable device for implementing the process. Figure 1 a process or multiple processes and / or boxes Figure 1 A step that specifies a function in one or more boxes.

[0093] Although the preferred embodiments of the present application have been described, those skilled in the art may make additional changes and modifications to these embodiments once they have learned the basic creative concept. Therefore, the appended claims are intended to be interpreted as including the preferred embodiments and all changes and modifications that fall within the scope of the present application.

[0094] Obviously, those skilled in the art may make various changes and modifications to this application without departing from the spirit and scope of this application. Thus, if these modifications and variations of this application fall within the scope of the claims of this application and their equivalents, this application is intended to include these modifications and variations.

Claims

1. A method for calculating line impedance of a mesh shielding structure, characterized in that: Includes the following: Obtaining the conductor width and spacing of the mesh shielding layer, and calculating the ratio of the signal leakage of the mesh shielding layer to the signal transmission of the electrical formation, where the signal transmission of the electrical formation refers to the signal transmission between the dielectric layer and the mesh shielding layer; Obtain the dielectric thickness parameters of the dielectric layer, equate the signal leakage of the mesh shielding layer to an increase in dielectric thickness, and calculate the equivalent dielectric thickness based on the leakage ratio and dielectric thickness parameters; Obtain the angle between the impedance line and the horizontal edge of the mesh shielding layer, the dielectric constant of the dielectric layer, and calculate the equivalent dielectric constant based on the time equivalence principle; Obtain the line width and copper thickness of the impedance line, and calculate the line impedance by combining the equivalent dielectric thickness, equivalent dielectric constant, and the classic characteristic impedance calculation formula.

2. The line impedance calculation method of the mesh shielding structure according to claim 1, characterized in that: The escape ratio is calculated based on the following formula: Where η represents the dissipation ratio, a and b represent the conductor width and spacing of the mesh shield layer, respectively.

3. The line impedance calculation method of the mesh shielding structure according to claim 1, characterized in that: The equivalent dielectric thickness is calculated based on the following formula: Where h′ represents the equivalent dielectric thickness, h represents the dielectric thickness parameter of the dielectric layer, and η represents the dissipation ratio.

4. The line impedance calculation method of the mesh shielding structure according to claim 1, wherein: The specific process of calculating the equivalent dielectric constant based on the time equivalence principle is: In a single grid, the actual transmission time of the electrical signal is t = (1 + cosθ + sinθ) l / v, c represents the speed of light, ε r Represents the dielectric constant of the dielectric layer, θ represents the angle between the impedance line and the horizontal side of the grid shielding layer, l represents the length of the hypotenuse of a single grid, according to the time equivalence principle, assuming that the transmission length is 2l, then ε′ r represents the equivalent dielectric constant, so 5. The line impedance calculation method of the mesh shielding structure according to claim 1, wherein: The line impedance of the mesh shielding structure is calculated based on the following formula: Where Z1 represents the line impedance, ε r represents the dielectric constant of the dielectric layer, a and b represent the conductor width and spacing of the mesh shield layer, respectively, θ represents the angle between the impedance line and the horizontal side of the mesh shield layer, w and t represent the line width and copper thickness of the impedance line, respectively, and h represents the dielectric thickness parameter of the dielectric layer.

6. The line impedance calculation method of the mesh shielding structure according to claim 1, characterized in that: The mesh shielding layer is infinitely wide relative to the impedance line in the width direction; or, the mesh shielding layer is larger than one side of the impedance line by more than 3 mm in the width direction.

7. A line impedance calculation system for a mesh shielding structure, characterized in that: include: A first calculation module is used to obtain the conductor width and spacing of the mesh shielding layer, and calculate the signal leakage ratio of the mesh shielding layer to the electrical formation signal transmission amount, where the electrical formation signal transmission amount refers to the signal transmission amount between the dielectric layer and the mesh shielding layer; The second calculation module is used to obtain the dielectric thickness parameter of the dielectric layer, equate the signal leakage of the grid shielding layer to the increase in dielectric thickness, and calculate the equivalent dielectric thickness based on the leakage ratio and the dielectric thickness parameter; The third calculation module obtains the angle between the impedance line and the horizontal edge of the mesh shielding layer, the dielectric constant of the dielectric layer, and calculates the equivalent dielectric constant based on the time equivalence principle; The fourth calculation module is used to obtain the line width and copper thickness of the impedance line, and calculate the line impedance by combining the equivalent dielectric thickness, equivalent dielectric constant and the classic characteristic impedance calculation formula.

8. The line impedance calculation system of the mesh shielding structure according to claim 7, characterized in that: The fourth calculation module calculates the line impedance of the mesh shielding structure based on the following formula: Where Z1 represents the line impedance, ε r represents the dielectric constant of the dielectric layer, a and b represent the conductor width and spacing of the mesh shield layer, respectively, θ represents the angle between the impedance line and the horizontal side of the mesh shield layer, w and t represent the line width and copper thickness of the impedance line, respectively, and h represents the dielectric thickness parameter of the dielectric layer.

9. An electronic device, characterized in that: The method comprises a processor and a memory, wherein the memory stores a computer program, and the processor is configured to execute the steps of the method according to any one of claims 1 to 6 by calling the computer program stored in the memory.

10. A computer-readable storage medium for storing a computer program for calculating line impedance of a mesh shielding structure, characterized in that: When the computer program is run on a computer, the steps of the method according to any one of claims 1 to 6 are executed.

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