Ultra-wideband four-channel tapered power divider based on impedance transformation ratio and its design method

Abstract

This invention relates to an ultra-wideband four-way tapered line power divider based on impedance transformation ratio and its design method. The design method includes the following steps: obtaining the design requirements of the tapered line power divider; calculating the impedance transformation ratio; designing each segment of the tapered line according to the impedance transformation value; modeling and simulating a single tapered line; determining whether the performance requirements are met based on the insertion loss and VSWR of the single tapered line; if met, calculating the odd-even mode impedance sequence; otherwise, re-establishing the model of the single tapered line and simulating it; calculating the isolation resistance value sequence; establishing and simulating a 1-to-2 power divider model; determining whether the performance requirements are met based on the insertion loss, isolation, and VSWR of the 1-to-2 power divider; if met, establishing and simulating the overall model of the ultra-wideband four-way tapered line power divider; otherwise, recalculating the isolation resistance value sequence. Compared with the prior art, this invention adopts a novel bent structure and appropriate impedance transformation values, and the designed ultra-wideband four-way tapered line power divider has the advantages of high area utilization, short line length, and low insertion loss.

Description

Technical Field

[0001] This invention relates to the field of passive power dividers, and in particular to an ultra-wideband four-channel tapered line power divider based on impedance transformation ratio and its design method. Background Technology

[0002] Wideband Wilkinson power dividers are widely used in wireless and measurement systems. The main performance characteristics of a four-way power divider include transmission, reflection, and isolation. For two-port matched networks with different port impedances, multi-section impedance transformers and tapered line impedance transformers are used to improve broadband transmission and reflection performance. The reflection bandwidth of multi-section impedance transformers is limited by the number of sections, while tapered lines can theoretically exhibit infinite reflection bandwidth. To improve bandwidth, CN113904088A discloses a design method for an ultra-wideband power divider based on a vertically mounted substrate. First, using the circuit structure given by the equivalent circuit diagram, multiple coupled lines are connected in series to simulate the actual tapered line. The odd and even mode impedance values ​​of each node are obtained through simulation optimization using two-dimensional electromagnetic simulation software. The obtained odd and even mode impedances are divided into strongly coupled and weakly coupled parts. Finally, a function curve is fitted using the physical dimensions of each node obtained in the previous steps, and modeled and optimized in three-dimensional electromagnetic simulation software. However, in this scheme, the remaining area of ​​the substrate is large, the utilization rate is low, the line length is long, and the insertion loss is also relatively large. Summary of the Invention

[0003] The purpose of this invention is to provide an ultra-wideband four-channel tapered line power divider based on impedance transformation ratio and its design method. Based on an appropriate impedance transformation ratio, the insertion loss of the power divider is reduced, and the tapered line is established using a dataset obtained from simulation, resulting in higher accuracy. In terms of structure, a novel bending structure is used, which improves the area utilization of the substrate and reduces the line length.

[0004] The objective of this invention can be achieved through the following technical solutions:

[0005] A design method for an ultra-wideband four-channel tapered line power divider based on impedance transformation ratio includes the following steps:

[0006] S1, Obtain the design requirements of the gradient line power divider and select a gradient line to achieve transmission;

[0007] S2, Design the impedance transformation ratio of each section of the transmission line and calculate the characteristic impedance value of each section;

[0008] S3, Design the gradient line of each section according to the characteristic impedance value of each section;

[0009] S4. Calculate the transmission line width based on the design parameters of each section of the gradient line, establish a model of a single gradient line and perform simulation.

[0010] S5. Determine whether the single tapered line meets the performance index requirements based on the insertion loss and VSWR. If it does, calculate the odd-mode impedance sequence based on the modeling results of the single tapered line. Otherwise, return to step S4 and adjust the model of the single tapered line.

[0011] S6, Calculate the isolation resistance value sequence based on the odd-mode impedance sequence;

[0012] S7. Establish and simulate a one-to-two power divider based on the isolation resistor value sequence.

[0013] S8. Based on the insertion loss, isolation, and VSWR of the 1-to-2 power divider, determine whether it meets the performance requirements. If it does, establish the overall model of the ultra-wideband four-way tapered line power divider based on the model of the 1-to-2 power divider and perform simulation. Otherwise, return to step S6 and recalculate the isolation resistance value sequence.

[0014] The design requirements include reflection coefficient, line length, isolation, and insertion loss.

[0015] S2 includes the following steps:

[0016] S21, Design the impedance transformation ratio of each transmission line according to the number of transmission lines required by the power divider;

[0017] S22, based on the impedance transformation ratio of each transmission line and the structure of the four-channel tapered line power divider, calculates the characteristic impedance value of each single line.

[0018] The structure of the four-way tapered line power divider is as follows: the input impedance Z0 and the load impedance Z4 are the same, the total impedance transformation ratio is 4, and the impedance transformation stage is three. The input impedance Z0 is matched to the load impedance Z4 after passing through a three-stage single-wire impedance transformation tapered line and a transition structure at both ends. In this section, the third single wire is bent and split into two, with intermediate impedances Z1, Z2, and Z3. The design formula for the impedance transformation ratio of each transmission line section is as follows:

[0019] 2Z1 / Z2=K1

[0020] Z2 / Z3=K2

[0021] 2Z3 / Z0=K3

[0022] K1*K2*K3=4

[0023] Where Z1, Z2, Z3, and Z0 represent the characteristic impedances of the first single-wire input of the four channels, the second single-wire input of the three channels, and the total input impedance of the transmission line, respectively; K i (i = 1, 2, 3) represents the characteristic impedance ratio of each section.

[0024] To ensure that each section of the transmission line has the same length, K1 = K2 = K3 is set.

[0025] S3 includes the following steps:

[0026] S31, Selecting a gradient line: For each section of transmission line, determine its port impedance and load impedance based on the characteristic impedance value calculated in step S2, calculate the load reflection coefficient, calculate the ripple value in the passband based on the maximum reflection coefficient limited in the passband, calculate intermediate variables based on the load reflection coefficient and the ripple value in the passband, and select different types of gradient lines based on the intermediate variables.

[0027] S32, Segmenting the gradient line: Based on the port impedance, load impedance, wavelength, total length of the gradient line, and the maximum reflection coefficient within the passband of each transmission line section, and creating a length partitioning array according to the total length of the gradient line, the gradient line is segmented to obtain the characteristic impedance sequence of the gradient line.

[0028] S4 includes the following steps:

[0029] S41, Establish a dataset corresponding to characteristic impedance values ​​and line width dimensions;

[0030] S42, call the dataset and use interpolation to determine the line width corresponding to each segment in the gradient line characteristic impedance sequence obtained in step S3;

[0031] S43. Establish a single gradient line model, set simulation parameters and perform simulation to analyze the reflection and transmission characteristics of the gradient line within the operating frequency range.

[0032] The calculation of the odd-mode impedance sequence based on the modeling results of a single gradient line includes the following steps:

[0033] S51, based on the modeling results of a single gradient line, read the S-parameter dataset from the simulation results;

[0034] S52, calculate the Z parameters based on the S parameters: Z = Z0*(I+S) / (IS), where I is the identity matrix, S is the S parameter matrix, Z is the Z parameter matrix, and the Z parameter matrix is ​​divided into 4 sub-matrices according to the size of the S parameters;

[0035] S53, calculate the first and second matrices based on the submatrices of the Z-parameter matrix;

[0036] S54, perform eigenvalue decomposition on the first matrix to obtain the eigenvector matrix and the eigenvalue matrix;

[0037] S55, Odd-mode impedance calculation:

[0038] Normalize the eigenvector matrix;

[0039] The principal value of the transmission constant is calculated based on the eigenvalue matrix, and phase defolding is performed to remove redundant up-hop and down-hop points from the principal value of the transmission constant.

[0040] Calculate the complex propagation constant based on the principal values ​​of the eigenvector matrix and the propagation constant;

[0041] Calculate the characteristic impedance based on the eigenvector matrix, the principal value of the transmission constant, and the second matrix;

[0042] Calculate odd-mode impedance based on complex propagation constant and characteristic impedance.

[0043] The method for calculating the isolation resistance value sequence is as follows:

[0044]

[0045] Among them, G k The following values ​​represent the electrical conductivity, l represents the bus length, Δz represents the specified unit length of the gradient line, A represents the maximum reflection coefficient of the gradient line within the passband, Γ0 represents the terminal reflection coefficient, and T... i Let represent the transmission coefficient between each section, F represent the adjustment factor, k represent the sequence number of each section, and I1(x) represent the first-order modified Bessel function.

[0046] A=acosh(Γ ld / Γ rip )

[0047]

[0048] Among them, Γ ld Γ represents the load reflection coefficient. rip This indicates the ripple value within the passband, where 'a' represents a custom scale and 'Y' represents the ripple value within the passband. i G represents the admittance value, which is the reciprocal of the tapered line isolation resistor sequence. i It represents the reciprocal of the isolation resistance, i.e., the conductance.

[0049] An ultra-wideband four-channel tapered line power divider is designed using the method described above.

[0050] Compared with the prior art, the present invention has the following beneficial effects:

[0051] 1. This invention proposes a design method for a four-way power divider based on the determination of the impedance transformation ratio. This method is applicable to the design of a four-way tapered Wilkinson power divider with infinite bandwidth. By determining the impedance transformation ratio, this method effectively reduces the transmission line length, thereby reducing the device size and greatly reducing insertion loss.

[0052] 2. This invention proposes a method for obtaining datasets through simulation, and uses datasets of line width and characteristic impedance, along with an interpolation method, to design gradient lines, thereby improving the design accuracy of gradient lines.

[0053] 3. The high-isolation ultrawideband four-channel tapered line power divider designed in this invention exhibits excellent performance in terms of reflection, isolation, and insertion loss in broadband response. Attached Figure Description

[0054] Figure 1 This is a flowchart of the method of the present invention;

[0055] Figure 2 This is a schematic diagram of the four-way power divider structure of the present invention;

[0056] Figure 3 This is a model diagram of the four-way power divider designed for this invention;

[0057] Figure 4 The simulation results of the four-way power divider designed in this invention are shown in the figure. Detailed Implementation

[0058] The present invention will now be described in detail with reference to the accompanying drawings and specific embodiments. These embodiments are based on the technical solution of the present invention and provide detailed implementation methods and specific operating procedures. However, the scope of protection of the present invention is not limited to the following embodiments.

[0059] Example 1

[0060] This embodiment provides a design method for an ultra-wideband four-channel tapered line power divider based on impedance transformation ratio, such as... Figure 1 As shown, it includes the following steps:

[0061] S1. Obtain the design requirements of the gradient line power divider (including reflection coefficient, line length, isolation and insertion loss, etc.), and select the gradient line to achieve transmission;

[0062] S2, Design the impedance transformation ratio of each section of the transmission line and calculate the characteristic impedance value of each section;

[0063] S2 includes the following steps:

[0064] S21, Design the impedance transformation ratio of each transmission line according to the number of transmission lines required by the power divider;

[0065] S22, based on the impedance transformation ratio of each transmission line and the structure of the four-channel tapered line power divider, calculates the characteristic impedance value of each single line.

[0066] like Figure 2As shown, the structure of the four-way taper line power divider is as follows: the input impedance Z0 and the output load impedance Z4 are the same. Since all four output ports of the four-way power divider are Z0, if they are directly connected, Z0 will be connected in parallel to form 1 / 4 Z0. Therefore, the total impedance transformation ratio is 4, and the number of impedance transformation stages is three. The input impedance Z0 is matched to the load impedance Z4 after passing through three stages of single-wire impedance transformation taper lines and transition structures at both ends. In this case, the third single wire is bent and split into two, with intermediate impedances Z1, Z2, and Z3. Z0 and Z4 are 50Ω. The design formula for the impedance transformation ratio of each transmission line section is as follows:

[0067] 2Z1 / Z2=K1

[0068] Z2 / Z3=K2

[0069] 2Z3 / Z0=K3

[0070] K1*K2*K3=4

[0071] Where Z1, Z2, Z3, and Z0 represent the characteristic impedances of the first single-wire input of the four channels, the second single-wire input of the three channels, and the total input impedance of the transmission line, respectively; K i (i = 1, 2, 3) represents the characteristic impedance ratio of each section.

[0072] In this embodiment, to ensure that each transmission line section has the same length, K1 = K2 = K3 is set. Therefore, given the values ​​of K1, K2, K3, and Z0, Z1, Z2, and Z3 can be calculated.

[0073] S3, Design the gradient line of each section according to the characteristic impedance value of each section;

[0074] S3 includes the following steps:

[0075] S31, Selecting a tapered line: For each transmission line section, determine its port impedance and load impedance based on the characteristic impedance value calculated in step S2, calculate the load reflection coefficient, calculate the ripple value in the passband based on the maximum reflection coefficient limited within the passband, calculate intermediate variables based on the load reflection coefficient and the ripple value in the passband, and select different types of tapered lines based on the intermediate variables, such as Klopfenstein tapered lines, exponential tapered lines, or trigonometric function tapered lines; taking the first single line section as an example, its port impedance is Z1 and its load impedance is Z2; the port impedance of the second single line section is Z2 and its load impedance is Z3; the port impedance of the third single line section is 2Z3 and its load impedance is Z4.

[0076] S32, Segmenting the gradient line: Based on the port impedance, load impedance, wavelength, total length of the gradient line, and the maximum reflection coefficient within the passband of each transmission line section, and creating a length partitioning array according to the total length of the gradient line, the gradient line is segmented to obtain the characteristic impedance sequence of the gradient line.

[0077] S4. Calculate the transmission line width based on the design parameters of each section of the gradient line, establish a model of a single gradient line and perform simulation.

[0078] S4 includes the following steps:

[0079] S41, Establish a dataset corresponding to characteristic impedance values ​​and linewidth dimensions: Set the Rogers 5880 substrate material parameters, substrate thickness, conductor thickness, line spacing, line length, and substrate width. Through joint simulation using Matlab and HFSS, scan the linewidth values ​​to obtain S-parameters. Extract the characteristic impedance values ​​from the S-parameters to obtain the dataset of stripline linewidth and S-parameters. The formula for extracting characteristic parameters from S-parameters is as follows:

[0080]

[0081] Where Z0 represents the input impedance, S 11 and S 21 Z is derived from the S-parameter dataset obtained through simulation. c This represents the extracted characteristic impedance value.

[0082] S42, call the dataset and use interpolation to determine the line width corresponding to each segment in the gradient line characteristic impedance sequence obtained in step S3;

[0083] S43. A single gradient line model was established using Matlab-HFSS-API. Simulation parameters were set and simulations were performed to analyze the reflection and transmission characteristics of the gradient line within the operating frequency range.

[0084] S5. Determine whether the single tapered line meets the performance index requirements based on the insertion loss and VSWR. If it does, calculate the odd-mode impedance sequence based on the modeling results of the single tapered line. Otherwise, return to step S4 and adjust the model of the single tapered line.

[0085] The calculation of the odd-mode impedance sequence based on the modeling results of a single gradient line includes the following steps:

[0086] S51, based on the modeling results of a single gradient line, read the S-parameter dataset from the simulation results;

[0087] S52, Calculate the Z parameters based on the S parameters: Z = Z0 * (I + S) / (IS), where I is the identity matrix, S is the S parameter matrix, and Z is the Z parameter matrix. Divide the Z parameter matrix into 4 sub-matrices according to the size of the S parameters:

[0088] Z 11 =Z([1N / 2],[1N / 2],fre);

[0089] Z 12=Z([1N / 2],[N / 2+1N],fre);

[0090] Z 21 =Z([N / 2+1N],[1N / 2],fre);

[0091] Z 22 =Z([N / 2+1N],[N / 2+1N],fre)

[0092] Where fre is the current frequency.

[0093] S53, Calculate the first matrix P and the second matrix Q based on the submatrices of the Z-parameter matrix:

[0094] P = Z 11 / Z 21 ;

[0095] Q = Z 11 / Z 21 *Z 22 -Z 12 .

[0096] S54, perform eigenvalue decomposition on the first matrix P to obtain the eigenvector matrix E and the eigenvalue matrix VA;

[0097] S55, Odd-mode impedance calculation:

[0098] S551, normalize the eigenvector matrix E;

[0099] S552, calculate the principal value of the transmission constant based on the eigenvalue matrix VA: γ = acos(VA), and perform phase defolding to remove redundant up-hop and down-hop points in the principal value of the transmission constant;

[0100] S553, Calculate the complex propagation constant Γ based on the principal value of the eigenvector matrix E and the propagation constant γ:

[0101] Γ=EγE -1 =Ediag(γ1,γ2,…,γ) N E -1

[0102] S554, Calculate the characteristic impedance Z based on the eigenvector matrix E, the principal value of the transmission constant γ, and the second matrix Q. c :

[0103] Z c =E(sinhPV(γl)) -1 E -1 Q

[0104] S555, calculating odd-mode impedance based on complex propagation constant and characteristic impedance:

[0105]

[0106] Where ω represents frequency.

[0107] S6, Calculate the isolation resistance value sequence based on the odd-mode impedance sequence;

[0108] The method for calculating the sequence of isolation resistance values ​​is as follows:

[0109]

[0110] Among them, G k G represents the conductance value, which is the reciprocal of the resistance value. k =1 / R k R k This indicates the isolation resistance value of the tapered line, l represents the bus length, and Δ z The gradient line represents the specified unit length, usually 1 mm; A represents the maximum reflection coefficient of the gradient line within the passband; Γ0 represents the terminal reflection coefficient, usually 1 / 3; T i The transmission coefficient between each section is represented by F, the adjustment factor is represented by k, the sequence number of each section is represented by I1(x), and the function represents the first-order modified Bessel function.

[0111] A=acosh(Γ ld / Γ rip )

[0112]

[0113] Among them, Γ ld Γ represents the load reflection coefficient. rip This indicates the ripple value within the passband, where 'a' represents a custom scale and 'Y' represents the ripple value within the passband. i G represents the admittance value, which is the reciprocal of the tapered line isolation resistor sequence. i It represents the reciprocal of the isolation resistance, i.e., the conductance.

[0114] When the number of gradient line segments is too large, the conductivity value may become negative. Initially, F is 1. When a negative value occurs, the value of F is gradually increased, and a positive value will be recalculated. When using this formula, the required conductivity value is generated gradually through iteration.

[0115] S7. Establish and simulate a one-to-two power divider based on the isolation resistor value sequence.

[0116] S8. Based on the insertion loss, isolation, and VSWR of the 1-to-2 power divider, determine whether it meets the performance requirements. If it does, establish the overall model of the ultra-wideband four-way tapered line power divider based on the model of the 1-to-2 power divider and perform simulation. Otherwise, return to step S6 and recalculate the isolation resistance value sequence.

[0117] Example 2

[0118] This embodiment provides an ultra-wideband four-channel tapered line power divider, which is designed using the method described in Embodiment 1. Figure 3 The simulation model diagram is shown, with specific dimensions of 98.8mm x 55mm, which is significantly smaller than the size of existing commercial power dividers (commonly 158mm x 74mm). The S-parameter simulation results are as follows. Figure 4 As shown, it exhibits outstanding performance response with an additional insertion loss of only 2dB. This performance fully meets the performance requirements of ultra-wideband four-way power dividers on the market, and greatly improves the utilization rate of the substrate area. At the same time, it also reduces the line length and lowers the insertion loss.

[0119] The preferred embodiments of the present invention have been described in detail above. It should be understood that those skilled in the art can make numerous modifications and variations based on the concept of the present invention without creative effort. Therefore, all technical solutions that can be obtained by those skilled in the art based on the concept of the present invention through logical analysis, reasoning, or limited experimentation on the basis of existing technology should be within the scope of protection defined by the claims.

Claims

1. A design method for an ultra-wideband four-channel tapered line power divider based on impedance transformation ratio, characterized in that, Includes the following steps: S1, Obtain the design requirements of the gradient line power divider and select a gradient line to achieve transmission; S2, Design the impedance transformation ratio of each section of the transmission line and calculate the characteristic impedance value of each section; S3, Design the gradient line of each section according to the characteristic impedance value of each section; S4. Calculate the transmission line width based on the design parameters of each section of the gradient line, establish a model of a single gradient line and perform simulation. S5. Determine whether the single tapered line meets the performance index requirements based on the insertion loss and VSWR. If it does, calculate the odd-mode impedance sequence based on the modeling results of the single tapered line. Otherwise, return to step S4 and adjust the model of the single tapered line. S6, Calculate the isolation resistance value sequence based on the odd-mode impedance sequence; S7. Establish and simulate a one-to-two power divider based on the isolation resistor value sequence. S8. Based on the insertion loss, isolation and VSWR of the 1-to-2 power divider, determine whether it meets the performance index requirements. If it does, establish the overall model of the ultra-wideband four-way tapered line power divider based on the model of the 1-to-2 power divider and perform simulation. Otherwise, return to step S6 and recalculate the isolation resistance value sequence. The structure of the four-way tapered line power divider is as follows: the input impedance Z0 and the load impedance Z4 are the same, the total impedance transformation ratio is 4, and the impedance transformation stage is three. The input impedance Z0 is matched to the load impedance Z4 after passing through a three-stage single-wire impedance transformation tapered line and a transition structure at both ends. In this section, the third single wire is bent and split into two, with intermediate impedances Z1, Z2, and Z3. The design formula for the impedance transformation ratio of each transmission line section is as follows: Where Z1, Z2, Z3, and Z0 represent the characteristic impedances of the first single-wire input of the four channels, the second single-wire input of the three channels, and the total input impedance of the transmission line, respectively; K i (i=1,2,3) represents the characteristic impedance ratio of each section; To ensure that each section of the transmission line has the same length, K1=K2=K3 is set.

2. The design method of an ultra-wideband four-channel tapered line power divider based on impedance transformation ratio according to claim 1, characterized in that, The design requirements include reflection coefficient, line length, isolation, and insertion loss.

3. The design method for an ultra-wideband four-channel tapered line power divider based on impedance transformation ratio according to claim 1, characterized in that, S2 includes the following steps: S21, Design the impedance transformation ratio of each transmission line according to the number of transmission lines required by the power divider; S22, based on the impedance transformation ratio of each transmission line and the structure of the four-channel tapered line power divider, calculates the characteristic impedance value of each single line.

4. The design method of an ultra-wideband four-channel tapered line power divider based on impedance transformation ratio according to claim 1, characterized in that, S3 includes the following steps: S31, Selecting a gradient line: For each section of transmission line, determine its port impedance and load impedance based on the characteristic impedance value calculated in step S2, calculate the load reflection coefficient, calculate the ripple value in the passband based on the maximum reflection coefficient limited in the passband, calculate intermediate variables based on the load reflection coefficient and the ripple value in the passband, and select different types of gradient lines based on the intermediate variables. S32, Segmenting the gradient line: Based on the port impedance, load impedance, wavelength, total length of the gradient line, and the maximum reflection coefficient within the passband of each transmission line section, and creating a length partitioning array according to the total length of the gradient line, the gradient line is segmented to obtain the characteristic impedance sequence of the gradient line.

5. The design method of an ultra-wideband four-channel tapered line power divider based on impedance transformation ratio according to claim 1, characterized in that, S4 includes the following steps: S41, Establish a dataset corresponding to characteristic impedance values ​​and line width dimensions; S42, call the dataset and use interpolation to determine the line width corresponding to each segment in the gradient line characteristic impedance sequence obtained in step S3; S43. Establish a single gradient line model, set simulation parameters and perform simulation to analyze the reflection and transmission characteristics of the gradient line within the operating frequency range.

6. The design method of an ultra-wideband four-channel tapered line power divider based on impedance transformation ratio according to claim 1, characterized in that, The calculation of the odd-mode impedance sequence based on the modeling results of a single gradient line includes the following steps: S51, based on the modeling results of a single gradient line, read the S-parameter dataset from the simulation results; S52, Calculate Z parameters based on S parameters: Z = Z0 (I+S) / (IS), where I is the identity matrix, S is the S-parameter matrix, and Z is the Z-parameter matrix. The Z-parameter matrix is ​​divided into 4 sub-matrices according to the size of the S-parameters. S53, calculate the first and second matrices based on the submatrices of the Z-parameter matrix; S54, perform eigenvalue decomposition on the first matrix to obtain the eigenvector matrix and the eigenvalue matrix; S55, Odd-mode impedance calculation: Normalize the eigenvector matrix; The principal value of the transmission constant is calculated based on the eigenvalue matrix, and phase defolding is performed to remove redundant up-hop and down-hop points from the principal value of the transmission constant. Calculate the complex propagation constant based on the principal values ​​of the eigenvector matrix and the propagation constant; Calculate the characteristic impedance based on the eigenvector matrix, the principal value of the transmission constant, and the second matrix; Calculate odd-mode impedance based on complex propagation constant and characteristic impedance.

7. The design method of an ultra-wideband four-channel tapered line power divider based on impedance transformation ratio according to claim 1, characterized in that, The method for calculating the isolation resistance value sequence is as follows: in, G k Indicates the conductivity value. l Indicates the bus length. z This indicates the specified unit length of the gradient line. A Γ0 represents the maximum reflection coefficient of the gradient line within the passband, and Γ0 represents the terminal reflection coefficient. T i This represents the transmission coefficient between each section. F Indicates the adjustment factor. k This indicates the section number. I 1( x The function represents the first-order modified Bessel function. Among them, Γ ld Γ represents the load reflection coefficient. rip Indicates the ripple value within the passband. a Indicates a custom ratio. Y i This represents the admittance value, which is the reciprocal of the tapered line isolation resistor sequence. It represents the reciprocal of the isolation resistance, i.e., the conductance.

8. An ultra-wideband four-channel tapered line power divider, characterized in that, The ultra-wideband four-channel tapered line power divider is designed using the method described in any one of claims 1-7.

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