High-frequency signal transmission method in pre-branched cable

Abstract

The invention relates to the technical field of pre-branch cable medium-high frequency signal transmission, in particular to a pre-branch cable medium-high frequency signal transmission method, which comprises the following steps of: constructing an asymmetric gradient chamfer branch structure; embedding a distributed wave absorbing layer; tDR feedback optimization of topology constraints is carried out; carrying out three-dimensional conformal shielding waveguide processing; joint iteration calibration is carried out; and the high-frequency pre-branch cable is closed-loop and standardized cooperatively. The asymmetric gradient chamfer branch structure is adopted, an electromagnetic field is forced to keep a TEM mode on a main transmission path, modal distortion is effectively reduced, the fidelity of signal transmission is improved, the reflection coefficient of a branch point caused by impedance abrupt change is synchronously reduced by optimizing the chamfer angle and embedding the distributed wave absorbing layer, and the transmission efficiency of the antenna is improved. The influence of reflection and multipath effect on signal transmission is reduced, and through TDR feedback optimization of topology constraint and three-dimensional conformal shielding waveguide, branch layout and shielding layer design are dynamically adjusted, and signal transmission efficiency and stability are improved.

Description

Technical Field

[0001] The present invention relates to the technical field of high-frequency signal transmission in a pre-branching cable, and in particular to a method for transmitting high-frequency signals in a pre-branching cable. Background Art

[0002] Pre-branched cable is a cable system with a pre-designed and installed branch structure, which is used to provide multiple branch points on the cable line to provide power or signal transmission for different devices or systems. This cable system is usually used in situations where multiple branch points are required, such as power distribution inside buildings, data centers, communication base stations, etc.

[0003] The high-frequency signal in the pre-branch cable refers to the electrical signal with a higher frequency transmitted in the pre-branch cable. These signals may be used in applications such as high-speed data transmission, wireless communication, radar systems, etc. High-frequency signals are easily affected by various factors during transmission, such as signal attenuation, reflection, multipath effect, etc., so special design and optimization methods are required to ensure stable signal transmission.

[0004] Generally, traditional cable design and selection will select the appropriate cable type and specifications according to application requirements, design branch points on the cables, and usually use simple right-angle or arc-shaped branch structures to transmit high-frequency signals to the target device through the cables and branch points, and receive and process the signals at the target device end. However, this traditional right-angle or arc-shaped branch structure can easily cause modal conversion of the electromagnetic field, resulting in signal distortion and energy loss. Impedance mismatch at the branch point can cause reflected waves, and multipath effects can cause signal interference and attenuation. High-frequency signals are easily interfered with by environmental noise and other signals during transmission, resulting in a decrease in signal quality. Traditional branch cable design lacks systematic optimization and standardized processes, and it is difficult to ensure the stability and reliability of signal transmission.

[0005] Based on this, the present invention provides a method for transmitting high-frequency signals in a pre-branching cable to solve the above-mentioned technical problems. Summary of the invention

[0006] The purpose of the present invention is to provide a method for transmitting high-frequency signals in a pre-branching cable, so as to solve the problems proposed in the above-mentioned background technology that the traditional right-angle or arc-shaped branch structure is prone to cause modal conversion of the electromagnetic field, resulting in signal distortion and energy loss, and the impedance mismatch at the branch point will cause reflected waves. At the same time, the multipath effect will cause signal interference and attenuation. The high-frequency signal is easily interfered by environmental noise and other signals during the transmission process, resulting in a decrease in signal quality. The traditional branch cable design lacks systematic optimization and standardized processes, and it is difficult to ensure the stability and reliability of signal transmission.

[0007] To achieve the above object, the present invention provides the following technical solutions: A method for transmitting high frequency signals in a pre-branching cable is provided, comprising the following steps: S1. Construct an asymmetric gradient chamfered branch structure; S2. Distributed absorbing layer embedded; S3. Topology-constrained TDR feedback optimization; S4. Three-dimensional conformal shielding waveguiding; S5. Joint iterative calibration; S6. Collaborative closure and standardization of high-frequency pre-branch cables.

[0008] As a preferred technical solution of the high frequency signal transmission method in the pre-branching cable of the present invention, the implementation steps of step S1 are: S1.1. For mode conversion, an asymmetric gradient chamfer geometry is used to introduce a continuous transition of curvature at the branch point, so that the radius of curvature matches the wavelength order, forcing the electromagnetic field to maintain the TEM mode on the main transmission path; S1.2. By optimizing the chamfer angle to 45°~60°, the reflection coefficient caused by impedance mutation at the branch point is simultaneously reduced, and the reflected energy attenuation is ≥10 dB; S1.3. Based on 30 GHz millimeter wave band wavelength , define the chamfer length: ; HFSS full-wave simulation is used to verify the convergence of the field distribution.

[0009] As a preferred technical solution of the high frequency signal transmission method in the pre-branching cable of the present invention, the implementation steps of step S2 are: S2.1. A nano-ferrite-graphene composite absorbing layer with a thickness of ≤0.1 mm is covered on the branch point conductor surface to actively absorb high-order mode energy through magneto-electric coupling loss. The dielectric constant gradient ε_r of the absorbing layer changes gradually from 3.0 to 6.0 to match the branch point and trunk impedance and suppress the reflected waves generated by the discontinuous interface. S2.2. The absorbing layer is deposited on the surface of the copper conductor using a magnetron sputtering process to ensure that there are no bubbles at the interface with the insulating layer.

[0010] As a preferred technical solution of the high frequency signal transmission method in the pre-branching cable of the present invention, the implementation steps of step S3 are: S3.1. Use a time domain reflectometer to measure the reflection peak position and amplitude of the branch cable, inversely calculate the multipath reflection path length difference ΔL, and establish a reflection path topology map; S3.2. Input the ΔL data into the topology optimization algorithm, constrain the branch point spacing to satisfy ΔL>λ / 2, destroy the coherence condition of the reflected wave, and use the genetic algorithm to iteratively adjust the branch layout so that the peak-to-peak value of the TDR reflection coefficient is ≤0.05.

[0011] As a preferred technical solution of the high frequency signal transmission method in the pre-branching cable of the present invention, the implementation steps of step S4 are: S4.1. Construct a three-dimensional metalized conformal shielding layer on the outer wall of the branch point, specifically a copper plating layer plus a conductive epoxy resin filling, to form a waveguide-like structure with a cutoff frequency higher than the working frequency band; S4.2. Suppress the propagation of high-order modes, seamlessly connect the shielding layer with the trunk shielding, use the waveguide characteristics to block the near-field coupling between branches, and eliminate the source of multipath reflection energy; S4.3. Laser-induced chemical plating is used to achieve uniform metallization of complex curved surfaces, and conductive glue is filled at the joints, with a resistance of ≤0.1 Ω / cm². As a preferred technical solution for the high-frequency signal transmission method in the pre-branching cable of the present invention, the implementation steps of step S5 are: S5.1. Take the chamfer curvature, absorbing layer gradient, topology ΔL and shielding cutoff frequency in the method of steps S1 to S4 as joint variables, compare the HFSS simulation with the TDR measured data, and establish a multi-objective optimization function as follows: Target 1. TEM mode energy share ≥ 95% (S parameter |S11| ≤ -20 dB); Objective 2. Inter-symbol interference power ratio ≤ 5%; S5.2. Use the covariance matrix adaptive evolution strategy (CMA-ES) to perform 10 to 20 rounds of iterations until convergence. As a preferred technical solution of the high-frequency signal transmission method in the pre-branching cable of the present invention, the implementation steps of step S6 are: S6.1. Process closed-loop verification and error tolerance calibration; S6.2. Perform multi-band compatibility verification; S6.3. Conversion of key parameters and production specifications, converting optimized design variables into producible engineering parameters, and then constructing cross-length adaptation rules.

[0012] As an optimal technical solution for the high-frequency signal transmission method in the pre-branching cable of the present invention, in the step S6.1, the chamfer curvature, absorbing layer gradient, and topology ΔL optimization results of step S5 are imported into the HFSS simulation model, compared with the S parameters and time domain reflection waveform measured by TDR, and the allowable error tolerance is defined. If the error exceeds the tolerance, local iteration of steps S1 to S5 is triggered.

[0013] As a preferred technical solution of the high-frequency signal transmission method in the pre-branching cable of the present invention, in step S6.2, three characteristic frequencies are selected in the target frequency band, and steps S1 to S5 are repeated for optimization to verify parameter robustness.

[0014] Compared with the prior art, the present invention has the following beneficial effects: The present invention adopts an asymmetric gradually chamfered branch structure to force the electromagnetic field to maintain the TEM mode on the main transmission path, effectively reduce modal distortion, and improve the fidelity of signal transmission. By optimizing the chamfer angle and embedding a distributed absorbing layer, the reflection coefficient caused by the impedance mutation at the branch point is simultaneously reduced, and the influence of reflection and multipath effects on signal transmission is reduced. Through topologically constrained TDR feedback optimization and three-dimensional conformal shielding waveguiding, the branch layout and shielding layer design are dynamically adjusted to improve signal transmission efficiency and stability. Through joint iterative calibration and process closed-loop verification, the repeatability of the method and the accuracy of the parameters are ensured. At the same time, cross-length adaptation rules and production compatibility process conversion are constructed to improve production efficiency and product quality. In summary, the method of the present invention is particularly suitable for high-frequency signal transmission applications, including but not limited to millimeter wave communication and high-speed data transmission, and can meet the high requirements of these applications for signal transmission performance and stability. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Figure 1 This is a flow chart of the high-frequency signal transmission method in the pre-branching cable of the present invention. DETAILED DESCRIPTION

[0016] The following will be combined with the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention. Example

[0017] See also Figure 1 The present invention proposes a method for transmitting high-frequency signals in a pre-branching cable, comprising the following steps: S1. Construct an asymmetric gradient chamfered branch structure; In this embodiment, it should be noted that the implementation steps of step S1 are: S1.1. For mode conversion, an asymmetric gradient chamfer geometry is used to introduce a continuous transition of curvature at the branch point, so that the radius of curvature matches the wavelength order, forcing the electromagnetic field to maintain the TEM mode on the main transmission path; S1.2. By optimizing the chamfer angle to 45°~60°, the reflection coefficient caused by impedance mutation at the branch point is simultaneously reduced, and the reflected energy attenuation is ≥10 dB; S1.3. Based on 30 GHz millimeter wave band wavelength , define the chamfer length: ; Use HFSS full-wave simulation to verify the convergence of field distribution.

[0018] S2. Distributed absorbing layer embedded; In this embodiment, it should be noted that the implementation steps of step S2 are: S2.1. Cover the branch point conductor surface with a nano-ferrite-graphene composite absorbing layer with a thickness of ≤0.1 mm, actively absorb the high-order mode energy through magneto-electric coupling loss, and the dielectric constant gradient ε_r of the absorbing layer gradually changes from 3.0 to 6.0, matching the branch point and trunk impedance, and suppressing the reflected waves generated by the discontinuous interface; S2.2. Use magnetron sputtering technology to deposit the absorbing layer on the surface of the copper conductor to ensure that there are no bubbles at the interface with the insulating layer.

[0019] S3. Topology-constrained TDR feedback optimization; In this embodiment, it should be noted that the implementation steps of step S3 are: S3.1. Use a time domain reflectometer to measure the reflection peak position and amplitude of the branch cable, inversely calculate the multipath reflection path length difference ΔL, and establish a reflection path topology map; S3.2. Input the ΔL data into the topology optimization algorithm, constrain the branch point spacing to satisfy ΔL>λ / 2, destroy the coherence condition of the reflected wave, and use the genetic algorithm to iteratively adjust the branch layout so that the peak-to-peak value of the TDR reflection coefficient is ≤0.05.

[0020] S4. Three-dimensional conformal shielding waveguide; In this embodiment, it should be noted that the implementation steps of step S4 are: S4.1. Construct a three-dimensional metalized conformal shielding layer on the outer wall of the branch point, specifically a copper plating layer plus a conductive epoxy resin filling, to form a waveguide-like structure with a cutoff frequency higher than the working frequency band; S4.2. Suppress the propagation of high-order modes, seamlessly connect the shielding layer with the trunk shielding, use the waveguide characteristics to block the near-field coupling between branches, and eliminate the source of multipath reflection energy; S4.3. Laser-induced chemical plating is used to achieve uniform metallization of complex curved surfaces, and the joints are filled with conductive glue, with a resistance of ≤0.1 Ω / cm².

[0021] S5. Joint iterative calibration; In this embodiment, it should be noted that the implementation steps of step S5 are: S5.1. Take the chamfer curvature, absorbing layer gradient, topology ΔL and shielding cutoff frequency in the method of steps S1 to S4 as joint variables, compare the HFSS simulation with the TDR measured data, and establish a multi-objective optimization function as follows: Target 1. TEM mode energy share ≥ 95% (S parameter |S11| ≤ -20 dB); Objective 2. Inter-symbol interference power ratio ≤ 5%; S5.2. Use the covariance matrix adaptive evolution strategy (CMA-ES) for 10 to 20 rounds of iterations until convergence.

[0022] S6. Collaborative closure and standardization of high-frequency pre-branch cables.

[0023] In this embodiment, it should be noted that the implementation steps of step S6 are: S6.1. Process closed-loop verification and error tolerance calibration; S6.2. Perform multi-band compatibility verification; S6.3. Conversion of key parameters and production specifications, converting optimized design variables into producible engineering parameters, and then constructing cross-length adaptation rules.

[0024] In this embodiment, it should also be noted that in step S6.1, the chamfer curvature, absorbing layer gradient, and topology ΔL optimization results of step S5 are imported into the HFSS simulation model, compared with the S parameters and time domain reflection waveform measured by TDR, and the allowable error tolerance is defined. If the error exceeds the tolerance, local iteration of steps S1 to S5 is triggered.

[0025] In this embodiment, it should also be noted that in step S6.2, three characteristic frequencies are selected within the target frequency band, and steps S1 to S5 are repeated for optimization to verify parameter robustness. Example

[0026] In practical applications, the method for transmitting high-frequency signals in a pre-branching cable of the present invention specifically includes the following steps: (1) Design an asymmetric gradient chamfered branch structure to suppress modal conversion and reduce branch point reflection, thus achieving synergistic suppression of the two problems; By constructing an asymmetric tapered chamfered branch structure through step (1), the electromagnetic field is forced to maintain the TEM mode on the main transmission path through the asymmetric tapered chamfered geometry, thereby suppressing the modal conversion, effectively reducing the modal distortion, and improving the fidelity of signal transmission; 1.1) Chamfer parameters match wavelength Calculation of radius of curvature: According to the operating frequency (such as 30GHz, λ=10mm), the chamfer curvature radius R must meet the following requirements: ; Among them, the medium ε_r=2.3, then R≥2.1mm, take R=2.5mm; Gradient Angle Optimization: Adopt piecewise linear gradient (asymmetric), the chamfer angle θ1 = 45° on the main transmission path side (gradual change to reduce modal distortion), and θ2 = 60° on the branch side (steep to reduce reflection); Electromagnetic field constraint verification: In HFSS, set: Boundary conditions: The radiation boundary extends beyond λ / 4; Meshing: The mesh size in the curvature area is ≤λ / 20 (0.5mm); Excitation port: The number of wave port modes is 5 to ensure that high-order modes are captured; Through step 1.1), for mode conversion, an asymmetric gradient chamfer geometry is adopted to introduce a continuous transition of curvature, so that the radius of curvature matches the wavelength magnitude, ensuring a smooth transition of the electromagnetic field and reducing energy loss; 1.2) Joint modeling of chamfer and absorbing layer Material interface optimization: A 50μm groove is preset on the chamfered surface, and a nano-ferrite-graphene composite absorbing layer (ratio Fe3O4:C=3:7) is embedded, and the impedance is matched by gradually changing the interface gradient ε_r from 2.5 to 5.0; Laser etching was used to process grooves on the surface of the copper conductor, and the absorbing layer was deposited by magnetron sputtering (sputtering power 200W, Ar gas flow rate 20sccm), and then annealed at 300℃ to eliminate stress; By optimizing the chamfer angle to 45°~60° in step 1.2), the reflection coefficient caused by impedance mutation at the branch point is simultaneously reduced, the reflection energy is significantly reduced, and the signal transmission efficiency is improved; 1.3) Reflection suppression verification Time Domain Reflectometry (TDR) Testing: A step signal with a rising edge of 1ps is injected into a single branch point and the reflection coefficient Γ is measured: If Γ>-15dB, adjust the chamfer angle θ2 to 65°; If Γ≤-15dB and the field distribution converges, enter the topology optimization stage; Through step 1.3), define the chamfer length based on the wavelength of the 30 GHz millimeter wave band, and use HFSS full-wave simulation to verify the convergence of the field distribution, ensure the accuracy of the design, and optimize the signal transmission performance; (2) Embedding of distributed absorbing layer; Through step (2) of embedding a distributed absorbing layer, a nano-ferrite-graphene composite absorbing layer is covered on the branch point conductor surface to actively absorb high-order mode energy, effectively suppress high-order modes, and reduce signal interference; 2.1) A nano-ferrite-graphene composite absorbing layer with a thickness of ≤0.1 mm is covered on the surface of the branch point conductor to actively absorb the energy of the high-order mode through magneto-electric coupling loss. The dielectric constant gradient ε_r of the absorbing layer gradually changes from 3.0 to 6.0, matching the branch point and trunk impedance, and suppressing the reflected waves generated by the discontinuous interface; Through step 2.1), a wave absorbing layer with a thickness of ≤0.1 mm is covered, and the dielectric constant of the wave absorbing layer is gradually changed to match the branch point and trunk impedance, thereby reducing the reflected waves caused by impedance mismatch and improving the signal transmission quality; 2.2) Use magnetron sputtering process to deposit the absorbing layer on the surface of the copper conductor to ensure that there are no bubbles at the interface with the insulating layer; In step 2.2), the absorbing layer is deposited by a magnetron sputtering process to ensure that there are no bubbles at the interface between the absorbing layer and the insulating layer, thereby improving the stability and reliability of the absorbing layer; (3) Topology-constrained TDR feedback optimization, inferring the multipath path through measured reflection data and dynamically adjusting the branch layout to destroy the coherence condition; Through the topology-constrained TDR feedback optimization in step (3), the multipath path is inferred from the measured reflection data, the branch layout is dynamically adjusted, the coherence condition of the reflected wave is destroyed, and the multipath reflection interference is reduced; 3.1) TDR multipath inversion algorithm Data collection: Inject TDR pulses (10ps pulse width, 5V amplitude) at all branch ports of the cable and record the time series of the reflected waveforms at each port, t1, t2, ... t n ; Path difference calculation: The reflection peak time difference Δt is extracted by cross-correlation algorithm, and the path length difference ΔL=Δt×v_p is inversely calculated (v_p is the signal propagation speed, which is taken as 0.7c); Constraints: Force ΔL>λ / 2 (ΔL>5mm at 30GHz); Through step 3.1), the reflection path topology map is established, and the multipath reflection path length difference ΔL is inferred to provide accurate data support for topology optimization; 3.2) Genetic algorithm topology optimization Coding rules: The branch position coordinates (x, y, z) and length L are encoded as chromosomes. Each gene represents a branch parameter. Specifically, x∈[0,L_total], and the fitness function is: ; Where α=0.6, β=0.4, Γ_i is the reflection coefficient of each branch point, and ΔL_j is the path difference; Iteration strategy: Population size: 50; Crossover rate: 0.8, mutation rate: 0.05; Termination condition: F change < 1% for 5 consecutive generations or total number of iterations ≥ 100; In step 3.2), the genetic algorithm is used to iteratively adjust the branch layout, constrain the branch point spacing to satisfy ΔL>λ / 2, optimize the branch layout, and reduce reflection interference; 3.3) Dynamic feedback adjustment Branch length fine-tuning: If there are still branch pairs with ΔL≤λ / 2 after optimization, use a piezoelectric ceramic micro-displacer with an accuracy of ±0.01mm to stretch / compress the branch cable until ΔL>λ / 2; Shield layer adaptive correction: For the branch points after movement, the shielding layer is reinforced by laser-induced chemical plating (plating thickness ≥ 2μm, resistance ≤ 0.05Ω / sq); (4) Three-dimensional conformal shielding waveguide Through step (4) of three-dimensional conformal shielding waveguiding, a three-dimensional metalized conformal shielding layer is constructed on the outer wall of the branch point to form a waveguide-like structure, block the near-field coupling between branches, and eliminate the source of multipath reflection energy; 4.1) Construct a three-dimensional metalized conformal shielding layer on the outer wall of the branch point, specifically a copper plating layer plus a conductive epoxy resin filling, to form a waveguide-like structure with a cutoff frequency higher than the working frequency band; Through step 4.1), a three-dimensional metallized conformal shielding layer is constructed, and the cut-off frequency is higher than the working frequency band, which effectively suppresses the propagation of high-order modes and improves the stability of signal transmission; 4.2) Suppress the propagation of high-order modes, the shielding layer is seamlessly connected with the trunk shielding, and the near-field coupling between branches is blocked by waveguide characteristics to eliminate the source of multipath reflection energy; Through step 4.2), the shielding layer is seamlessly connected with the trunk shielding, and the waveguide characteristics are used to block the near-field coupling between branches and reduce mutual interference between signals; 4.3) Laser-induced chemical plating is used to achieve uniform metallization of complex curved surfaces, and conductive glue is filled at the joints, with a resistance of ≤0.1 Ω / cm²; Through step 4.3), laser-induced chemical plating is used to achieve uniform metallization of complex curved surfaces, and conductive glue is filled at the joints, with a resistance of ≤0.1 Ω / cm², to improve the conductivity and reliability of the shielding layer; (5) Joint iterative calibration Through the joint iterative calibration in step (5), the chamfer curvature, the absorbing layer gradient, the topology ΔL and the shielding cutoff frequency are optimized as joint variables, and the overall performance of signal transmission is improved through multi-objective optimization; 5.1) The chamfer curvature, absorbing layer gradient, topology ΔL and shielding cutoff frequency in the methods of step S1 to step S4 are used as joint variables, and the multi-objective optimization function is established by comparing the HFSS simulation with the TDR measured data, as follows: Target 1. TEM mode energy share ≥ 95% (S parameter |S11| ≤ -20 dB); Objective 2. Inter-symbol interference power ratio ≤ 5%; Establish a multi-objective optimization function through step 5.1) and compare the HFSS simulation with the TDR measured data to ensure the accuracy and reliability of the optimization results; 5.2) Use the covariance matrix adaptive evolution strategy (CMA-ES) for 10 to 20 rounds of iterations until convergence; Specifically, the implementation process is: Chamfer design → TDR initial measurement: After completing steps 1.1) to 1.3), obtain the initial reflection data Γ and ΔL; Topology optimization → chamfer correction: If the branch position output by the genetic algorithm conflicts with the chamfer curvature, and the curvature radius is less than 2.1 mm, return to step 1.1 to adjust the chamfer parameters; Final verification: Perform full-band frequency sweep (26.5~33.5GHz) on the optimized cable, with the following requirements: TEM mode proportion ≥ 95% (measured by mode analyzer); Inter-symbol interference power ratio ≤ 3% (calculated by bit error rate tester); Among them, it is also necessary to explain: The chamfer curvature matches the wavelength: to avoid edge field distortion caused by insufficient curvature. When R=2.5mm, the high-order mode suppression ratio is increased by 12dB. TDR inversion accuracy control uses Gaussian pulse fitting algorithm to improve the path difference resolution to 0.1mm level; Genetic algorithm acceleration, the introduction of GPU parallel computing (CUDA acceleration), reduces the iteration time of 100 generations from 2 hours to 8 minutes; In step 5.2), the covariance matrix adaptive evolution strategy is used to iterate until convergence, and the parameters such as the chamfer curvature and the absorbing layer gradient are optimized to improve the optimization efficiency and ensure the optimality of the optimization results; (6) Closing loop and standardization of high-frequency pre-branch cable collaborative design process Through step (6) high frequency pre-branch cable coordinated closed loop and standardization, through process closed loop verification and error tolerance calibration, the repeatability of the method is ensured, and through standardized processes, production efficiency and product quality are improved; 6.1) Process closed-loop verification and error tolerance calibration Comparison of simulation and measured data: The chamfer curvature, absorbing layer gradient, and topology ΔL optimization results of step (5) are imported into the HFSS simulation model, compared with the S parameters (|S11|, |S21|) and time domain reflection waveform measured by TDR, and the allowable error tolerance is defined: a. The error between simulation and measured TEM mode energy is ≤±2%; b. Peak-to-peak deviation of reflection coefficient ≤±0.02; c. If the deviation is exceeded, trigger the local iteration of steps (1) to (5), and only adjust the deviation variable; Multi-band compatibility verification: Select 28 GHz, 30 GHz, and 32 GHz characteristic frequencies within the target frequency band, repeat optimization steps (1) to (5), and verify parameter robustness. Through step 6.1) process closed-loop verification and error tolerance calibration, the optimization results are imported into the HFSS simulation model and compared with the TDR measured data to ensure the accuracy and reliability of the design parameters; 6.2) Key parameter solidification and production specification conversion Parameter mapping table generation: The optimized design variables are converted into producible engineering parameters, and the cross-length adaptation rule is: For different total cable lengths L_total, the relationship between the chamfer length L and L_total is defined by a piecewise function: ; Perform multi-band compatibility verification through step 6.2), select characteristic frequencies within the target frequency band, repeat the optimization process, verify the robustness of the parameters, and improve the applicability of the product; 6.3) Production compatibility process conversion Chamfering process adaptation: Convert HFSS optimized chamfer surface data into five-axis CNC machining programs: Tool path generation: Based on asymmetric chamfer angles (θ1=45°, θ2=60°), contour layered milling is used; Surface roughness control: Ra≤0.8μm, to prevent high-frequency skin depth fluctuations; Shielding layer production line adaptation: Convert laser induced electroless plating parameters into production line equipment instructions: Plating solution formula: CuSO480g / L+H2SO420g / L+additive JGB-53mL / L; Laser parameters: wavelength 532nm, power 50W, scanning speed 2mm / s; Through step 6.3), the key parameters are solidified and converted into production specifications, and the optimized design variables are converted into producible engineering parameters, providing accurate technical guidance for production and improving production efficiency; 6.4) Design-Production Coupling Linkage rulebook: Prepare a table of parameter coupling relationships between steps and clarify the priority of conflict resolution: Version control and iteration trigger: Define the design version number rule, VerX.YZ, where X = frequency band, Y = topology complexity, Z = number of iterations, and set revision trigger conditions; a. Operating frequency change ≥ ±10%; b. When new materials are introduced, the dielectric constant changes by ≥±15%; c. The production yield rate is less than 95% for three consecutive batches; Through step 6.4) design-production coupling, compile a parameter coupling relationship table between steps, clarify the conflict resolution priority, ensure seamless connection between design and production, and improve the overall performance of the product; In this step, simulation-actual measurement comparison and error calibration are used to ensure the repeatability of the method, convert theoretical optimization parameters into executable process instructions, avoid the "design-manufacturing gap", solidify multi-step linkage rules through documentation, prevent local optimization from causing global performance degradation, and ensure the coordinated solution of modal conversion and multipath reflection through process standardization. Example

[0027] In practical applications, the practical application process of the high-frequency signal transmission method in the pre-branching cable of the present invention is as follows: Design of asymmetric tapered chamfer branch structure: The branch structure is designed with asymmetric tapered chamfer geometry to ensure that the electromagnetic field maintains the TEM mode on the main transmission path and suppress modal conversion. The chamfer curvature radius is calculated according to the operating frequency, and the chamfer angle is optimized to reduce the reflection coefficient of the branch point. The HFSS full-wave simulation is used to verify the convergence of the field distribution to ensure the accuracy of the design.

[0028] Distributed absorbing layer embedding: The surface of the branch point conductor is covered with a nano-ferrite-graphene composite absorbing layer, which actively absorbs high-order mode energy through magneto-electric coupling loss, ensures that there are no bubbles between the absorbing layer and the conductor surface, and improves the stability and reliability of the absorbing layer.

[0029] Topology-constrained TDR feedback optimization: The reflection peak position and amplitude of the branch cable are measured by time domain reflectometry (TDR), and the multipath reflection path length difference is inferred using the cross-correlation algorithm to establish a reflection path topology map. The branch layout is iteratively adjusted using a genetic algorithm to ensure that the spacing between branch points meets specific conditions, thereby destroying the coherence conditions of the reflected wave and reducing multipath reflection interference.

[0030] Three-dimensional conformal shielding waveguiding: A three-dimensional metalized conformal shielding layer is constructed on the outer wall of the branch point to form a waveguide-like structure, which suppresses the propagation of high-order modes, ensures seamless connection between the shielding layer and the trunk shielding, uses the waveguide characteristics to block the near-field coupling between branches, and uses laser-induced chemical plating to achieve uniform metallization of complex surfaces to ensure the conductivity and reliability of the shielding layer.

[0031] Joint iterative calibration: The chamfer curvature, absorbing layer gradient, topological layout and shielding cutoff frequency are taken as joint variables. Through HFSS simulation and TDR measured data comparison, a multi-objective optimization function is established. The covariance matrix adaptive evolution strategy (CMA-ES) is used for iterative optimization until convergence to ensure the overall optimal performance of signal transmission.

[0032] Closed-loop and standardized collaborative design process for high-frequency pre-branching cables: Import the optimization results into the HFSS simulation model, compare them with the TDR measured data, define the allowable error tolerance, ensure the accuracy and reliability of the design parameters, select the characteristic frequency within the target frequency band, repeat the optimization process, verify the robustness of the parameters, convert the optimized design variables into producible engineering parameters, build cross-length adaptation rules, convert the design parameters into production line equipment instructions, ensure the compatibility and efficiency of the production process, compile a parameter coupling relationship table between steps, clarify the conflict resolution priority, ensure seamless connection between design and production, define the design version number rules, and set revision trigger conditions to enable local iteration or comprehensive optimization when necessary.

[0033] Through the above-mentioned practical application steps, the present invention can effectively solve the problems of mode conversion and multipath reflection in high-frequency signal transmission in the pre-branching cable, improve the stability and reliability of signal transmission, and is suitable for the fields of high-frequency communication and data transmission.

[0034] In the description of this specification, the description with reference to the terms "one embodiment", "example", "specific example", etc. means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representation of the above terms does not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described can be combined in any one or more embodiments or examples in a suitable manner.

[0035] The preferred embodiments of the present invention disclosed above are only used to help illustrate the present invention. The preferred embodiments do not describe all the details in detail, nor do they limit the invention to the specific implementation methods described. Obviously, many modifications and changes can be made according to the content of this specification. This specification selects and specifically describes these embodiments in order to better explain the principles and practical applications of the present invention, so that those skilled in the art can understand and use the present invention well. The present invention is limited only by the claims and their full scope and equivalents.

Claims

1. A method for transmitting high frequency signals in a pre-branching cable, characterized in that: The following steps are involved: S1. Construct an asymmetric gradient chamfered branch structure; S2. Embedded distributed absorbing layer; S3. Perform topology-constrained TDR feedback optimization; S4. Implement three-dimensional conformal shielding waveguiding; S5. Perform joint iterative calibration; S6. Collaborative closure and standardization of high-frequency pre-branch cables.

2. A method for transmitting high frequency signals in a pre-branching cable according to claim 1, characterized in that: The implementation steps of step S1 are: S1.

1. For mode conversion, an asymmetric gradient chamfer geometry is used to introduce a continuous transition of curvature at the branch point, so that the radius of curvature matches the wavelength order, forcing the electromagnetic field to maintain the TEM mode on the main transmission path; S1.

2. By optimizing the chamfer angle to 45°~60°, the reflection coefficient caused by impedance mutation at the branch point is simultaneously reduced, and the reflected energy attenuation is ≥10 dB; S1.

3. Based on 30 GHz millimeter wave band wavelength , define the chamfer length: ; Use HFSS full-wave simulation to verify the convergence of field distribution.

3. A method for transmitting high frequency signals in a pre-branching cable according to claim 2, characterized in that: The implementation steps of step S2 are: S2.

1. Cover the branch point conductor surface with a nano-ferrite-graphene composite absorbing layer with a thickness of ≤0.1 mm, actively absorb the high-order mode energy through magneto-electric coupling loss, and the dielectric constant gradient of the absorbing layer gradually changes from 3.0 to 6.0 to match the branch point and trunk impedance, and suppress the reflected waves generated by the discontinuous interface; S2.

2. Use magnetron sputtering process to deposit the absorbing layer on the surface of the copper conductor to ensure that there are no bubbles at the interface with the insulating layer.

4. A method for transmitting high frequency signals in a pre-branching cable according to claim 3, characterized in that: The implementation steps of step S3 are: S3.

1. Use a time domain reflectometer to measure the reflection peak position and amplitude of the branch cable, inversely calculate the multipath reflection path length difference ΔL, and establish a reflection path topology map; S3.

2. Input the ΔL data into the topology optimization algorithm, constrain the branch point spacing to satisfy ΔL > λ / 2, destroy the coherence condition of the reflected wave, and use the genetic algorithm to iteratively adjust the branch layout so that the peak-to-peak value of the TDR reflection coefficient is ≤0.

05.

5. A method for transmitting high frequency signals in a pre-branching cable according to claim 4, characterized in that: The implementation steps of step S4 are: S4.

1. Construct a three-dimensional metallized conformal shielding layer on the outer wall of the branch point, specifically a copper plating layer plus a conductive epoxy resin filling, to form a waveguide-like structure with a cutoff frequency higher than the working frequency band; S4.

2. Suppress the propagation of high-order modes, seamlessly connect the shielding layer with the trunk shielding, use the waveguide characteristics to block the near-field coupling between branches, and eliminate the source of multipath reflection energy; S4.

3. Laser-induced chemical plating is used to achieve uniform metallization of complex curved surfaces, and the joints are filled with conductive glue, with a resistance of ≤0.1Ω / cm².

6. A method for transmitting high frequency signals in a pre-branching cable according to claim 5, characterized in that: The implementation steps of step S5 are: S5.

1. Take the chamfer curvature, absorbing layer gradient, topology ΔL and shielding cutoff frequency in the method of steps S1 to S4 as joint variables, compare the HFSS simulation with the TDR measured data, and establish a multi-objective optimization function as follows: Target 1. TEM mode energy ratio ≥ 95%; Objective 2. Inter-symbol interference power ratio ≤ 5%; S5.

2. Use the covariance matrix adaptive evolution strategy for 10 to 20 rounds of iterations until convergence.

7. A method for transmitting high frequency signals in a pre-branched cable according to claim 6, characterized in that: The implementation steps of step S6 are: S6.

1. Process closed-loop verification and error tolerance calibration; S6.

2. Perform multi-band compatibility verification; S6.

3. Conversion of key parameters and production specifications, converting optimized design variables into producible engineering parameters, and then constructing cross-length adaptation rules.

8. A method for transmitting high frequency signals in a pre-branched cable according to claim 7, characterized in that: In step S6.1, the chamfer curvature, absorbing layer gradient, and topology ΔL optimization results of step S5 are imported into the HFSS simulation model, compared with the S parameters and time domain reflection waveform measured by TDR, and the allowable error tolerance is defined. If the error exceeds the tolerance, local iteration of steps S1 to S5 is triggered.

9. A method for transmitting high frequency signals in a pre-branched cable according to claim 7, characterized in that: In step S6.2, three characteristic frequencies are selected within the target frequency band, and steps S1 to S5 are repeated for optimization to verify parameter robustness.

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