Adjustable power divider matched with impedance of any port

Abstract

The invention relates to the technical field of adjustable power dividers, in particular to an adjustable power divider matched with any port impedance, which comprises a transmission line structure power divider used for dividing an input signal into multiple paths for output; the input ends of the second impedance matching networks are connected with the output end of the transmission line structure power divider; wherein the second impedance matching network comprises an adjustable capacitor and an inductance element, and the second impedance matching network dynamically matches the impedances of different output ports by adjusting the capacitance value of the adjustable capacitor without changing the structural parameters of the transmission line. According to the adjustable power divider matched with the impedance of any port, the impedance matching networks which are formed by the adjustable capacitors and are connected in parallel are introduced into the output end of the power divider, real-time matching of different load impedances can be achieved only by adjusting capacitance values of the capacitors, a transmission line does not need to be redesigned or an isolator does not need to be additionally arranged, and the adjusting complexity is remarkably reduced.

Description

Technical Field

[0001] The present invention relates to the technical field of adjustable power dividers, and particularly to an adjustable power divider that matches the impedance of any port. Background Art

[0002] The power divider is a key device in the radio frequency system and is widely used in fields such as wireless communication and radar. The traditional Wilkinson power divider realizes power distribution by fixing the transmission line parameters, but once the port impedance matching is designed, it cannot be adjusted. When the impedance of the subsequent circuit changes, the standing wave ratio and insertion loss of the common port of the power divider deteriorate significantly, resulting in a decline in system performance. In the prior art, to solve this problem, usually two solutions are adopted: one is to improve the matching by adding isolators and attenuators, but it will increase the volume, weight and cost of the system; the other is to use a reconfigurable power divider, which switches paths through radio frequency switches, but its impedance matching range is limited and a complex control circuit is required.

[0003] For example, a prior art proposes to achieve impedance matching of any port by adjusting the transmission line parameters, but the characteristic impedance of the transmission line cannot be dynamically modified after processing, resulting in insufficient adaptation ability; another prior art uses a multi-impedance conversion network, but it only supports discrete impedance values, cannot cover the continuous impedance range, and relies on a large number of discrete components, resulting in a complex circuit. In addition, the prior arts have not solved the dynamic matching requirements of the power divider in the case of single-ended mismatch, and it is difficult to adapt to the scenario where the load impedance changes frequently in practical applications.

[0004] Therefore, there is an urgent need for a new power divider structure that can dynamically adapt the impedance of any port without changing the transmission line parameters or adding additional devices, while maintaining a compact structure and low cost. Summary of the Invention

[0005] The object of the present invention is to provide an adjustable power divider that matches the impedance of any port to solve the above technical problems.

[0006] The technical solution of the present invention is realized as follows:

[0007] An adjustable power divider that matches the impedance of any port, comprising: a transmission line structure power divider for dividing an input signal into multiple outputs; a plurality of second impedance matching networks connected in parallel, the input ends of the second impedance matching networks being connected to the output end of the transmission line structure power divider;

[0008] Wherein, the second impedance matching network includes an adjustable capacitor and an inductive element, and the second impedance matching network dynamically matches the impedance of different output ports by adjusting the capacitance value of the adjustable capacitor without changing the transmission line structure parameters.

[0009] Optionally, the second impedance matching network includes a first inductance unit, a first adjustable capacitance unit, and a second inductance unit arranged in sequence along the signal transmission direction. A first fixed capacitance unit is provided at the signal input end of the first inductance unit, a second adjustable capacitance unit is provided between the first inductance unit and the first adjustable capacitance unit, a third adjustable capacitance unit is provided between the first adjustable capacitance unit and the second inductance unit, and a second fixed capacitance unit is provided at the signal output end of the second inductance unit.

[0010] Optionally, one end of the first fixed capacitance unit is grounded, and the other end is connected to the signal input end of the first inductance unit; one end of the second adjustable capacitance unit is grounded, and the other end is connected between the first inductance unit and the first adjustable capacitance unit; one end of the third adjustable capacitance unit is grounded, and the other end is connected between the first adjustable capacitance unit and the second inductance unit; one end of the second fixed capacitance unit is grounded, and the other end is connected to the signal output end of the second inductance unit.

[0011] Optionally, the transmission line structure power divider includes a first impedance matching network and a plurality of transmission lines connected in parallel to the output end of the first impedance matching network. The transmission line is composed of a first transmission sub-line and a second transmission sub-line, and the characteristic impedance value Z1 corresponding to the first transmission sub-line and the characteristic impedance value Z2 corresponding to the second transmission sub-line satisfy the relationship: And the electrical lengths of both the first transmission sub-line and the second transmission sub-line are 90°.

[0012] Optionally, a resistor is provided between two adjacent transmission lines in the transmission line structure power divider, and the connection point of the resistor is located between the first transmission sub-line and the second transmission sub-line in the transmission line.

[0013] Optionally, the lengths of both the first transmission sub-line and the second transmission sub-line are one-quarter wavelength.

[0014] Optionally, the impedance matching network is based on the J-transformer principle, and the quarter-wavelength transmission line is equivalent to a cascaded Π-type network including a series inductor and a parallel adjustable capacitor to achieve multi-stage impedance conversion.

[0015] The beneficial effects of the present invention are:

[0016] The adjustable power divider for matching arbitrary port impedances according to the present invention introduces a plurality of impedance matching networks (IMNs) composed of adjustable capacitors connected in parallel at the output end of the power divider. By only adjusting the capacitance value of the capacitor, real-time matching of different load impedances can be achieved without re-designing the transmission line or adding an isolator, significantly reducing the adjustment complexity. Description of the Drawings

[0017] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the following will briefly introduce the drawings required for use in the embodiments. Obviously, the drawings in the following description are only some embodiments of the present invention. For those of ordinary skill in the art, without creative efforts, other drawings can also be obtained based on these drawings.

[0018] Figure 1 Schematic diagram of a power divider structure with arbitrary port impedance corresponding to the prior art solution 1;

[0019] Figure 2 N-way reconfigurable power divider corresponding to the prior art solution 2;

[0020] Figure 3 Schematic diagram of the adjustable power divider for matching arbitrary port impedance described in the embodiment;

[0021] Figure 4 Odd-mode excitation equivalent circuit described in the embodiment;

[0022] Figure 5 Even-mode excitation equivalent circuit described in the embodiment;

[0023] Figure 6 Impedance matching circuit based on J-transformer described in the embodiment;

[0024] Figure 7 Simplified circuit of the impedance matching network described in the embodiment;

[0025] Figure 8 Principle of capacitance implementation of the impedance matching circuit described in the embodiment;

[0026] Figure 9 Circuit diagram when the input / output port impedances of the two-way power divider described in the embodiment are both 50Ω;

[0027] Figure 10 Simulation result when the input / output port impedances of the two-way power divider described in the embodiment are both 50Ω;

[0028] Figure 11 Circuit diagram when the input port impedance of the two-way power divider described in the embodiment is 50Ω, the impedance of output port 1 is 75Ω, and the impedance of output port 2 is 35Ω;

[0029] Figure 12 Simulation result when the input port impedance of the two-way power divider described in the embodiment is 50Ω, the impedance of output port 1 is 75Ω, and the impedance of output port 2 is 35Ω;

[0030] Figure 13Circuit diagram when the input / output port impedances of the three-way power divider described in the embodiment are both 50 Ω

[0031] Figure 14 Simulation results when the input / output port impedances of the three-way power divider described in the embodiment are all 50 Ω

[0032] Figure 15 Circuit diagram when the input port impedance of the three-way power divider described in the embodiment is 50 Ω, the impedance of output port 1 is 75 Ω, the impedance of output port 2 is 50 Ω, and the impedance of output port 3 is 35 Ω

[0033] Figure 16 Simulation results when the input port impedance of the three-way power divider described in the embodiment is 50 Ω, the impedance of output port 1 is 75 Ω, the impedance of output port 2 is 50 Ω, and the impedance of output port 3 is 35 Ω

[0034] Figure 17 Circuit diagram when the input / output port impedances of the four-way power divider described in the embodiment are both 50 Ω

[0035] Figure 18 Simulation results when the input / output port impedances of the four-way power divider described in the embodiment are all 50 Ω

[0036] Figure 19 Circuit diagram when the input port impedance of the four-way power divider described in the embodiment is 50 Ω, the impedance of output port 1 is 75 Ω, the impedance of output port 2 is 65 Ω, the impedance of output port 3 is 45 Ω, and the impedance of output port 4 is 35 Ω

[0037] Figure 20 Simulation results when the input port impedance of the four-way power divider described in the embodiment is 50 Ω, the impedance of output port 1 is 75 Ω, the impedance of output port 2 is 65 Ω, the impedance of output port 3 is 45 Ω, and the impedance of output port 4 is 35 Ω Detailed implementation manners

[0038] Next, the technical solutions in the embodiments of the present invention will be clearly and completely described in conjunction with the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all of the embodiments.

[0039] In the description of the present invention, it should be understood that the orientation or positional relationship indicated by the terms "upper", "lower", "front", "rear", "left", "right", "top", "bottom", "inner", "outer", etc. is based on the orientation or positional relationship shown in the accompanying drawings, and is only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be construed as a limitation to the present invention.

[0040] Before elaborating on the solution of the present invention, it is necessary to elaborate on several existing solutions, so as to facilitate the understanding of the advantages of the solution of the present invention.

[0041] Existing technical solution one:

[0042] A power divider with arbitrary port impedance, and its schematic diagram is as Figure 1 shown. The proposed power divider is determined by two transmission lines and two series isolation resistors. According to the transmission line equation and the nodal equation, the design formula of the power divider with arbitrary port impedance is derived. According to the design equation, the power divider can meet the design requirements when the port impedances of the power splitter are different.

[0043] However, the above-mentioned power divider with arbitrary port impedance faces a key problem in practical applications: when the port impedance changes, it is necessary to recalculate and adjust the parameters of the transmission lines in the circuit to meet the design requirements. However, once the transmission lines are manufactured, their characteristic parameters are difficult to change, which results in the power divider being unable to achieve true arbitrary port impedance adaptation in actual operation.

[0044] Existing technical solution two:

[0045] An N-way reconfigurable power splitter, and its schematic diagram is as Figure 2 shown. The radio frequency switch is used to control the conduction and cut-off of a certain output port and the matching stub is used to adjust the input impedance. An impedance matching network is introduced at the input port. In order to achieve the matching performance under different transmission modes, a reconfigurable multi-impedance conversion network is introduced at the input port of the power splitter. Using the parameters of N-1 pin diodes under different bias conditions, N different load impedances can be converted into port impedances through the multi-impedance conversion network.

[0046] In the design process of the N-way reconfigurable power splitter, the reconfigurability of the power splitting path is mainly concerned, and the design requirements when the port impedance changes are not fully considered. This design idea results in the port impedance being limited to a fixed value and being unable to flexibly adapt to the working requirements under different impedance conditions. At the same time, the impedance matching circuit introduced at the input port of the N-way reconfigurable power splitter can only meet the impedance matching under different transmission path conditions. When the port impedance changes, the original circuit cannot meet the impedance matching.

[0047] Embodiment 1:

[0048] As Figure 3 shown, this embodiment provides an adjustable power divider that matches arbitrary port impedance, including:

[0049] A transmission line structure power divider for splitting an input signal into multiple outputs;

[0050] A plurality of second impedance matching networks (IMNs) are connected in parallel, and the input end of the second impedance matching network is connected to the output end of the transmission line structure power divider;

[0051] Wherein, the second impedance matching network includes an adjustable capacitor and an inductive element, and the second impedance matching network dynamically matches the impedance of different output ports by adjusting the capacitance value of the adjustable capacitor without changing the transmission line structure parameters.

[0052] Wherein, the specific structure of the impedance matching network includes a first inductive unit, a first adjustable capacitor unit, and a second inductive unit arranged in sequence along the signal transmission direction. A first fixed capacitor unit is provided at the signal input end of the first inductive unit, a second adjustable capacitor unit is provided between the first inductive unit and the first adjustable capacitor unit, a third adjustable capacitor unit is provided between the first adjustable capacitor unit and the second inductive unit, and a second fixed capacitor unit is provided at the signal output end of the second inductive unit. One end of the first fixed capacitor unit is grounded, and the other end is connected to the signal input end of the first inductive unit; one end of the second adjustable capacitor unit is grounded, and the other end is connected between the first inductive unit and the first adjustable capacitor unit; one end of the third adjustable capacitor unit is grounded, and the other end is connected between the first adjustable capacitor unit and the second inductive unit; one end of the second fixed capacitor unit is grounded, and the other end is connected to the signal output end of the second inductive unit.

[0053] The adjustable power divider for matching any port impedance proposed by the present invention is composed of a transmission line structure power divider and a matching circuit. The power divider realizes power distribution in the form of a transmission line, and the matching circuit realizes front / back stage circuit matching by adjusting the capacitance. Compared with the traditional Wilkinson power divider, the circuit structure proposed by the present invention enables the power divider to achieve matching when the port impedance changes simultaneously without changing the circuit structure while ensuring the basic functions of the power divider are realized. Compared with the reconfigurable power divider, the circuit proposed by the present invention realizes front / back stage circuit impedance matching by adjusting the capacitance value of the adjustable capacitor in the matching circuit, thereby meeting the requirement that the output port impedance does not have to be always consistent. This also broadens the adjustment range of the port impedance matching of the power divider, making it no longer limited to finite discrete values.

[0054] Figure 3 The structural schematic diagram of the adjustable power divider for matching any port impedance is shown. A signal source with an internal impedance of ZS enters the transmission line structure power divider through the input end impedance matching network module (IMN). The transmission line structure power divider injects the signal into the first transmission sub-line of the call branch through input port 1. The first transmission sub-line transmits the signal to the second transmission sub-line, and the other end of the second transmission sub-line is connected to the input end of the impedance matching circuit.

[0055] The power divider of the transmission line structure achieves impedance matching when the impedance of the input / output ports changes uniformly through a quarter-wavelength transmission line. The impedance matching circuit consists of inductors, capacitors, and variable capacitors. In actual use, corresponding to the change in the impedance of the signal source / load, the series capacitor C and the parallel capacitors (C1-C) are variable capacitors. By adjusting their capacitance values, the purpose of impedance matching at different impedances at the output end is achieved, and at the same time, the impedance matching adjustment range is also broadened.

[0056] Figures 4 - 5 The principle of the transmission line power divider is shown. In the odd-mode, a voltage (electric field) node is formed at the center of symmetry of the circuit, which is equivalent to the existence of an electric wall, so the input port is virtually grounded. At this time, Todd = 0 in the circuit, where Todd is the circuit transmission coefficient for odd-mode excitation. In the even-mode, a voltage (electric field) antinode is formed at the center of symmetry of the circuit, which is equivalent to the existence of a magnetic wall, so the symmetric points of the two branches at the input port are short-circuited. At this time, the input impedances of the two λ / 4 microstrip transmission lines Z1 and Z2 are respectively expressed as If it can meet the requirement of the circuit Z even = 2Z p (Z p is the port impedance). At the same time, a resistor R is connected between the two branches of the power divider, which changes the isolation characteristics between the two ports of the power divider. By reasonably adjusting the value of the variable capacitor, a good matching effect can be achieved.

[0057] Figures 6 - 7 The principle of the impedance matching network is shown. Since there may be a situation of single-ended mismatch in the power divider, an impedance matching circuit needs to be connected after the output port 1 and output port 2 of the power divider. This impedance matching circuit is based on the characteristics of the J-transformer and the quarter-wavelength transmission line, and can be equivalently split into three Π-type networks. The overall circuit transmission matrix after series connection can be equivalent to a J-transformer. Compared with the switch-controlled reconfigurable impedance matching network in the figure, this impedance matching circuit realizes impedance matching at both ends of the matching circuit by adjusting the variable capacitor, solves the limitation that the impedance of the input / output ports must be kept consistent, and at the same time expands the impedance adjustment range.

[0058] The adjustable power divider proposed in this embodiment realizes arbitrary impedance matching at the ports:

[0059] Arbitrary port impedance matching under the condition of consistent impedance of the input / output ports of the power divider is achieved through a quarter-wavelength transmission line;

[0060] Arbitrary impedance matching at the output ports is achieved by adding impedance matching networks to the two ports of the power divider respectively;

[0061] The impedance matching network does not adopt traditional matching networks such as T-type, Π-type, and L-type. Instead, it improves the traditional quarter-wavelength transmission line into an LC network. This topological structure combines the impedance characteristics of the power divider ports and can function as port impedance matching, thus achieving true arbitrary port impedance matching. By reasonably adjusting the value of the adjustable capacitor in the LC network, the power divider can achieve a good matching effect, avoid the use of isolators, and significantly reduce the volume and weight of the microwave channel.

[0062] Therefore, the present invention can be applied to the situation where different impedances are loaded on the power divider, can optimize the port impedance of the power divider to the greatest extent, ensure the port standing wave and insertion loss, avoid the use of isolators and attenuators, is beneficial to reducing the volume and weight of the product, and saving costs.

[0063] Embodiment 2:

[0064] This embodiment is based on Embodiment 1 and is used to provide several specific simulation cases.

[0065] The capacitor in this embodiment is connected between the output port and the load port of the power divider, as Figure 8 shown. This power divider can achieve output impedance matching by controlling the change of the capacitor. The implementation forms of the capacitor include fixed capacitors, varactor diodes, and switched capacitors, etc. By adjusting the number and size of the capacitor groups, different impedance tuning ranges can be achieved, thereby realizing continuous coverage of the port impedance of the power divider.

[0066] Simulation Case 1:

[0067] In this embodiment, there is a two-way power divider, as Figure 9 shown. For the transmission line power divider part, Z1 and Z2 respectively correspond to the characteristic impedance values of the first transmission sub-line and the second transmission sub-line. Select appropriate Z1 and Z2 values to satisfy At the same time, set the electrical lengths of the first transmission sub-line and the second transmission sub-line to be both 90°. For the impedance matching network part, L1 and C1 in the input / output port impedance matching network have the same parameter values. According to the actual impedance change range requirements, determine appropriate L1 and C1 values; by adjusting the capacitance values of the adjustable capacitors C2 / C3 in the input / output port impedance matching network, better port standing wave and insertion loss performance can be obtained. When the input port impedance (Z s ) / output port impedance (Z l1 , Z l2 ) are both 50Ω at the same time, the adjustable capacitors (C2, C3, C4) in the input / output port impedance matching network all take the value of 0.38 pf. The simulation results of the insertion loss and port standing wave of the power divider are as Figure 10 shown.

[0068] Simulation Case 2:

[0069] In this embodiment, it is a two-way power divider, as Figure 11 shown. When the input port impedance (Z s ) is 50 Ω, the output port 1 impedance (Z l1 ) is 75 Ω, and the output port 2 impedance (Z l2 ) is 35 Ω, with the remaining circuit parameters in Example 2 unchanged, the value of the adjustable capacitor (C3) on the corresponding branch of port 2 is taken as 0.46 pf, and the value of the adjustable capacitor (C4) on the corresponding branch of port 3 is taken as 0.32 pf. The simulation results of the insertion loss and port standing wave of the power divider are as Figure 12 shown.

[0070] Simulation Case 3:

[0071] In this embodiment, it is a three-way power divider, as Figure 13 shown. When the input port impedance (Z s ) / output port impedance (Z l1 , Z l2 , Z l3 ) are all 50 Ω, on the basis that the values of the components in each branch are the same as the circuit parameters of each branch in Example 2, the value of the adjustable capacitor (C2) in the input port impedance matching network is taken as 0.31 pf, and the values of the adjustable capacitors (C3, C4, C5) in the output port impedance matching network are all taken as 0.38 pf. The simulation results of the insertion loss and port standing wave of the power divider are as Figure 14 shown.

[0072] Simulation Case 4:

[0073] In this embodiment, it is a three-way power divider, as Figure 15 shown. When the input port impedance (Z s ) is 50 Ω, the output port 1 impedance (Z l1 ) is 75 Ω, the output port 2 impedance (Z l2 ) is 50 Ω, and the output port 3 impedance (Z l3 ) is 35 Ω, with the remaining circuit parameters in Example 4 unchanged, the value of the adjustable capacitor (C3) on the corresponding branch of port 2 is taken as 0.46 pf, the value of the adjustable capacitor (C4) on the corresponding branch of port 3 is taken as 0.38 pf, and the value of the adjustable capacitor (C5) on the corresponding branch of port 4 is taken as 0.32 pf. The simulation results of the insertion loss and port standing wave of the power divider are as Figure 16 shown.

[0074] Simulation Case 5:

[0075] In this embodiment, it is a four-way power divider, as Figure 17 shown. When the input port impedance (Z s ) / output port impedance (Zl1 , Z l2 , Z l3 , Z l4 ) When they are all 50 Ω, on the basis that the component values of each branch are the same as the circuit parameters of each branch in the second embodiment, the value of the adjustable capacitor (C2) in the input port impedance matching network is 0.27 pf, and the values of the adjustable capacitors (C3, C4, C5, C6) in the output port impedance matching network are all 0.38 pf. The simulation results of the insertion loss and port standing wave of the power divider are as Figure 18 shown.

[0076] Simulation case 6;

[0077] In this embodiment, it is a four-way power divider, as Figure 19 shown. When the input port impedance (Z s ) is 50 Ω, the output port 1 impedance (Z l1 ) is 75 Ω, the output port 2 impedance (Z l2 ) is 65 Ω, the output port 3 impedance (Z l3 ) is 45 Ω, and the output port 4 impedance (Z l4 ) is 35 Ω, when the other circuit parameters in the sixth embodiment remain unchanged, the value of the adjustable capacitor (C3) on the corresponding branch of port two is 0.46 pf, the value of the adjustable capacitor (C4) on the corresponding branch of port three is 0.44 pf, the value of the adjustable capacitor (C5) on the corresponding branch of port four is 0.34 pf, and the value of the adjustable capacitor (C6) on the corresponding branch of port five is 0.32 pf. The simulation results of the insertion loss and port standing wave of the power divider are as Figure 20 shown.

[0078] The above is only a preferred specific embodiment of the present invention, but the protection scope of the present invention is not limited thereto. Any person skilled in the art within the technical scope disclosed by the present invention, according to the technical solution and inventive concept of the present invention, makes equivalent substitutions or changes, and should be covered by the protection scope of the present invention.

Claims

1. An adjustable power divider that matches any port impedance, characterized in that Comprising: A transmission line structure power divider for dividing an input signal into multiple outputs; A plurality of second impedance matching networks connected in parallel, with the input ends of the second impedance matching networks connected to the output ends of the transmission line structure power divider; Wherein, the second impedance matching network includes an adjustable capacitor and an inductive element, and the second impedance matching network dynamically matches the impedances of different output ports by adjusting the capacitance value of the adjustable capacitor without changing the parameters of the transmission line structure.

2. The adjustable power divider for matching any port impedance according to claim 1, characterized in that, The second impedance matching network includes a first inductive unit, a first adjustable capacitor unit, and a second inductive unit arranged in sequence along the signal transmission direction, and a first fixed capacitor unit is provided at the signal input end of the first inductive unit, a second adjustable capacitor unit is provided between the first inductive unit and the first adjustable capacitor unit, a third adjustable capacitor unit is provided between the first adjustable capacitor unit and the second inductive unit, and a second fixed capacitor unit is provided at the signal output end of the second inductive unit.

3. An adjustable power divider for matching any port impedance according to claim 2, wherein One end of the first fixed capacitor unit is grounded, and the other end is connected to the signal input end of the first inductive unit; One end of the second adjustable capacitor unit is grounded, and the other end is connected between the first inductive unit and the first adjustable capacitor unit; One end of the third adjustable capacitor unit is grounded, and the other end is connected between the first adjustable capacitor unit and the second inductive unit; one end of the second fixed capacitor unit is grounded, and the other end is connected to the signal output end of the second inductive unit.

4. An adjustable power divider for matching any port impedance according to claim 1, wherein The transmission line structure power divider includes a first impedance matching network and a plurality of transmission lines connected in parallel to the output end of the first impedance matching network. The transmission line is composed of a first transmission sub-line and a second transmission sub-line, and the characteristic impedance value Z1 corresponding to the first transmission sub-line and the characteristic impedance value Z2 corresponding to the second transmission sub-line satisfy the relationship: Moreover, the electrical lengths of both the first transmission sub-line and the second transmission sub-line are 90°.

5. An adjustable power divider for matching any port impedance according to claim 4, characterized in that, A resistor is provided between adjacent two transmission lines in the transmission line structure power divider, and the connection point of the resistor is located between the first transmission sub-line and the second transmission sub-line in the transmission line.

6. The adjustable power divider for matching any port impedance according to claim 5, wherein The lengths of the first transmission sub-line and the second transmission sub-line are both one-quarter wavelength.

7. An adjustable power divider for matching any port impedance according to claim 6, characterized in that, The impedance matching network is based on the J-transformer principle, and the one-quarter wavelength transmission line is equivalent to a cascaded Π-type network including a series inductor and a parallel adjustable capacitor to achieve multi-stage impedance conversion.

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