CN113224491A - Miniaturized broadband four-way filtering power divider based on non-equal-width three-wire coupling structure - Google Patents

Miniaturized broadband four-way filtering power divider based on non-equal-width three-wire coupling structure Download PDF

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CN113224491A
CN113224491A CN202110402221.1A CN202110402221A CN113224491A CN 113224491 A CN113224491 A CN 113224491A CN 202110402221 A CN202110402221 A CN 202110402221A CN 113224491 A CN113224491 A CN 113224491A
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coupling
transmission line
wire
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CN113224491B (en
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刘宏梅
马逸涵
王雪娇
李晓婷
房少军
王钟葆
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Dalian Maritime University
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    • HELECTRICITY
    • H01ELECTRIC ELEMENTS
    • H01PWAVEGUIDES; RESONATORS, LINES, OR OTHER DEVICES OF THE WAVEGUIDE TYPE
    • H01P5/00Coupling devices of the waveguide type
    • H01P5/12Coupling devices having more than two ports
    • H01P5/16Conjugate devices, i.e. devices having at least one port decoupled from one other port
    • HELECTRICITY
    • H01ELECTRIC ELEMENTS
    • H01PWAVEGUIDES; RESONATORS, LINES, OR OTHER DEVICES OF THE WAVEGUIDE TYPE
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    • H01P1/20Frequency-selective devices, e.g. filters

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Abstract

The invention discloses a miniaturized broadband four-way filtering power divider based on a non-equal-width three-wire coupling structure, which comprises: the circuit comprises a non-equal-width three-wire coupling structure, an open-ended stepped impedance stub, a cross-over resistor and an input/output port; the unequal-width three-line coupling structure comprises a first unequal-width three-line coupling structure and a second unequal-width three-line coupling structure; the circuit size of the first unequal-width three-wire coupling structure is the same as that of the second unequal-width three-wire coupling structure; the terminal open-circuit stepped impedance branch comprises a first stepped impedance branch and a second stepped impedance branch; the first stepped impedance branch and the second stepped impedance branch have the same circuit size; the bridging resistor comprises a first bridging resistor, a second bridging resistor and a third bridging resistor; the first bridging resistor and the second bridging resistor have the same resistance value; the miniaturized four-path broadband filtering power divider provided by the invention has the characteristics of filtering response, wide working frequency band, stopband suppression, multi-path output, small size and low cost.

Description

Miniaturized broadband four-way filtering power divider based on non-equal-width three-wire coupling structure
Technical Field
The invention relates to the field of filtering power dividers, in particular to a miniaturized broadband four-path filtering power divider based on a non-equal-width three-line coupling structure.
Background
Under the era background of high demand of modern informatization, the wireless communication technology is rapidly developed. The development trend of communication technology with large capacity, high transmission rate, low cost and high performance also brings higher challenges and stricter requirements to the research and design of radio frequency microwave circuits. Therefore, the high-performance microwave passive device with broadband, miniaturization and low cost has great engineering application values such as necessity and practicability.
A power divider, called a power divider for short, is an important multi-port device. Its main function is to divide the input signal into two or more paths of signals according to a certain proportion and output them. Power splitters are widely used in various parts of wireless transceiving systems, such as in antenna feed systems, high power transmission systems, and in phase shifters, mixers, etc. The conventional planar multi-path power divider usually adopts a multi-stage transmission line connection mode for port expansion, and the common mode is to divide an input signal into two paths of signals for output, divide each path of output signal into two paths of signals for output, and so on to realize multi-port output signals. However, the design method is often large in size and narrow in bandwidth. The traditional method for realizing the broadband power division effect is to adopt a plurality of stages of impedance transformation lines matched with a plurality of isolation resistors, so that the broadband width can be expanded infinitely theoretically, and when the bandwidth is expanded to a certain degree, the volume of the power divider is overlarge.
In order to realize the broadband filtering function, K Song, Q Xue and the like realize an ultra-wideband filtering power divider by utilizing a multi-layer board microstrip line slot line coupling structure. The filter power divider has small size and ultra-wideband response. He Zhu et al designs a compact broadband four-way filtering power divider by introducing a ring-shaped coupling line and loading a short-circuit coupling line at an input end, and introduces a plurality of transmission zeros for inhibiting a stop band by the short-circuit parallel coupling line, so that the selectivity of the stop band inhibition and the pass band is improved. Gang Zhang et al realizes the dual functions of filtering and power division by introducing a multimode resonator, and realizes good isolation and passband selectivity.
Although the prior art realizes the design of a broadband filtering function, part of the prior art has the characteristics of large size and difficulty in realizing multi-path transmission simultaneously. Therefore, a power divider with filtering characteristics, wide operating frequency band, multiple outputs and small volume is needed.
Disclosure of Invention
According to the problems existing in the prior art, the invention discloses a miniaturized broadband four-way filtering power divider based on a non-equal-width three-wire coupling structure, which comprises: the circuit comprises a non-equal-width three-wire coupling structure, an open-ended stepped impedance stub, a cross-over resistor and an input/output port;
further, the unequal-width three-wire coupling structure comprises a first unequal-width three-wire coupling structure and a second unequal-width three-wire coupling structure; the circuit size of the first unequal-width three-wire coupling structure is the same as that of the second unequal-width three-wire coupling structure; the terminal open-circuit stepped impedance branch comprises a first stepped impedance branch and a second stepped impedance branch; the first stepped impedance branch and the second stepped impedance branch have the same circuit size; the bridging resistor comprises a first bridging resistor, a second bridging resistor and a third bridging resistor; the first bridging resistor and the second bridging resistor have the same resistance value; the first bridging resistor and the third bridging resistor have different resistance values; the input/output ports comprise an input port, a first output port, a second output port, a third output port and a fourth output port;
further, the first unequal-width three-wire coupling structure comprises a first coupling wire, a second coupling wire and a third coupling wire; the second unequal-width three-wire coupling structure comprises a fourth coupling wire, a fifth coupling wire and a sixth coupling wire; the first coupling line is the same as the third coupling line, the fourth coupling line and the sixth coupling line in size; the sizes of the second coupling line and the fifth coupling line are the same; the first coupling line and the second coupling line are different in size.
Further, the first ladder impedance stub comprises a first transmission line and a second transmission line; the second stepped impedance branch node comprises a third transmission line and a fourth transmission line; the first transmission line and the third transmission line are the same in size, and the second transmission line and the fourth transmission line are the same in size.
Furthermore, the input port is connected with the lower end of the first transmission line, the upper end of the first transmission line is connected with the left end of the second transmission line, and the right end of the second transmission line is open-circuited.
Furthermore, the input port is connected with the upper end of a third transmission line, the lower end of the third transmission line is connected with the left end of a fourth transmission line, and the right end of the fourth transmission line is open-circuited.
Furthermore, the input port is connected with the left end of the second coupling line, and the right end of the second coupling line is connected with the upper end of the third crossover resistor. The input port is connected with the left end of the fifth coupling line, and the right end of the fifth coupling line is connected with the lower end of the third bridging resistor.
Furthermore, the left end of the first coupling line is connected with the upper end of the first crossover resistor, and the right end of the first coupling line is connected with the first output port; the left end of the third coupling line is connected with the lower end of the first crossover resistor, and the right end of the third coupling line is connected with the second output port;
furthermore, the left end of the fourth coupling line is connected with the upper end of the second cross-over resistor, and the right end of the fourth coupling line is connected with the third output port; the left end of the sixth coupling line is connected with the lower end of the second bridging resistor, and the right end of the sixth coupling line is connected with the fourth output port;
further, let Zs1Is the characteristic impedance, Z, of the first transmission line and the third transmission lines2Is the characteristic impedance of the second transmission line and the fourth transmission line; theta is the electrical length of the first and second unequal-width three-wire coupling structures1Is the electrical length of the first and third transmission lines, θ2Is the electrical length, R, of the second transmission line and the fourth transmission line1Is the resistance value of the first and second bridge resistors, R2Is the resistance value of the third bridge resistance; zsRepresenting the matched impedance of the input port, ZLThe impedance matching device represents the matched impedance of the first output port, the second output port, the third output port and the fourth output port; the parity-mode analysis method has the following S parameter formula:
Figure BDA0003020834760000031
Figure BDA0003020834760000032
Figure BDA0003020834760000033
wherein
Figure BDA0003020834760000034
Figure BDA0003020834760000035
Figure BDA0003020834760000036
Resistance R1、R2The solving formula of (2) is as follows:
Figure BDA0003020834760000037
Figure BDA0003020834760000038
in the above formula, Zins、Z11、Z14、Z41、Z44、Z1、Z2、Z3、Z4、Z5、Z6And Z7Is an intermediate variable expressed as follows
Figure BDA0003020834760000041
Figure BDA0003020834760000042
Figure BDA0003020834760000043
K is an adjustable coefficient, and 0<K<1, parameter of
Figure BDA0003020834760000044
Representing the odd-even mode impedance of the asymmetric parallel coupling line formed by the first coupling line and the second coupling line; wherein the upper subscript a represents the first coupled line and b represents the second coupled line; and satisfy the conditions
Figure BDA0003020834760000045
Further, the first transmission line and the third transmission line are high impedance transmission lines, and the impedance value Z iss1Greater than 120 Ω; the second transmission line and the fourth transmission line are low-impedance transmission lines with impedance value Zs2Less than 50 Ω;
further, the electrical length theta of the unequal-width three-wire coupling structure is equal to pi/2 at the central frequency; electrical length theta of first transmission line1And the electrical length theta of the second transmission line2Both at the center frequency are pi/2;
further, the resistance values of the first bridging resistor and the second bridging resistor are both smaller than 200 Ω; the third bridging resistance value is greater than 400 omega; the first coupling line is wider than the second coupling line, and the line width ratio of the first coupling line to the second coupling line is larger than 10: 1.
The broadband power distribution system can realize the function of broadband power distribution, and has the advantages of filter response, simple structure, small size and the like; the selectivity of a passband can be adjusted by introducing a terminal open-circuit stepped impedance stub, so that wider stop band suppression is realized; meanwhile, the adoption of a non-equal-width three-wire coupling structure can realize simultaneous output of multiple ports in a plane and further reduce the circuit size of the power divider. Due to the adoption of the technical scheme, the miniaturized broadband four-way filtering power divider based on the non-equal-width three-wire coupling structure has the advantages of small volume, wide frequency band and good application in a radio frequency circuit, and is favorable for being widely popularized in a low-cost multi-application wireless communication system.
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In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the drawings needed to be used in the description of the embodiments or the prior art will be briefly described below, it is obvious that the drawings in the following description are only some embodiments described in the present application, and other drawings can be obtained by those skilled in the art without creative efforts.
Fig. 1 is a structural diagram of a miniaturized wideband four-way filter power divider based on a non-equal-width three-wire coupling structure according to the present invention;
FIG. 2 is a structure diagram of an even-even mode equivalent circuit under the odd-even mode analysis of the miniaturized broadband four-way filtering power divider based on the non-equal-width three-wire coupling structure according to the present invention;
FIG. 3 is a structural diagram of an even-odd mode equivalent circuit of the miniaturized broadband four-way filtering power divider based on the unequal-width three-wire coupling structure according to the present invention;
FIG. 4 is a structural diagram of an odd-even mode equivalent circuit of the miniaturized broadband four-way filtering power divider based on the unequal-width three-wire coupling structure according to the invention under the odd-even mode analysis;
FIG. 5 is a structure diagram of an odd-odd equivalent circuit of the miniaturized broadband four-way filter power divider based on the non-equal-width three-wire coupling structure according to the present invention;
fig. 6 is a graph of return loss and insertion loss S parameter when a signal is input from an input port in the miniaturized wideband four-way filter power divider based on the non-equal-width three-wire coupling structure according to the present invention;
fig. 7 is an S-parameter curve diagram of return loss of an output port of the miniaturized wideband four-way filtering power divider based on the non-equal-width three-wire coupling structure according to the present invention;
fig. 8 is a graph of an isolation S parameter between output ports of the miniaturized wideband four-way filter power divider based on the non-equal-width three-wire coupling structure according to the present invention;
in the figure: 11. the first unequal-width three-wire coupling structure 111, the first coupling line 112, the second coupling line 113, the third coupling line 12, the second unequal-width three-wire coupling structure 121, the fourth coupling line 122, the fifth coupling line 123, the sixth coupling line 21, the first stepped impedance stub 211, the first transmission line 212, the second transmission line 22, the second stepped impedance stub 221, the third transmission line 222, the fourth transmission line 31, the first crossover resistor 32, the second crossover resistor 33, the third crossover resistor 41, the input port 42, the first output port 43, the second output port 44, the third output port 45, and the fourth output port.
Detailed Description
In order to make the technical solutions and advantages of the present invention clearer, the present invention is further described in detail below with reference to the accompanying drawings in the embodiments of the present invention. It is to be understood that this description is intended for purposes of illustration only and is not intended to limit the scope of the present disclosure. Moreover, in the following description, descriptions of well-known structures and techniques are omitted so as to not unnecessarily obscure the concepts of the present invention.
Fig. 1 is a schematic structural diagram of a miniaturized wideband four-way filtering power divider based on a non-equal-width three-wire coupling structure according to the present invention, where the wideband filtering power divider of the present embodiment may include;
the invention relates to a miniaturized broadband four-way filtering power divider based on a non-equal-width three-wire coupling structure, which comprises a non-equal-width three-wire coupling structure 1, an open-ended stepped impedance branch 2, a bridging resistor 3 and an input/output port 4. The unequal-width three-wire coupling structure 1 comprises a first unequal-width three-wire coupling structure 11 and a second unequal-width three-wire coupling structure 12; the first unequal-width three-wire coupling structure 11 and the second unequal-width three-wire coupling structure 12 have the same circuit size; the terminal open-circuit stepped impedance branch 2 comprises a first stepped impedance branch 21 and a second stepped impedance branch 22; the first stepped impedance branch 21 and the second stepped impedance branch 22 have the same circuit size; the bridging resistor 3 comprises a first bridging resistor 31, a second bridging resistor 32 and a third bridging resistor 33; the first bridging resistor 31 and the second bridging resistor 32 have the same resistance value; the first bridging resistor 31 and the third bridging resistor 33 have different resistance values; the input/output port 4 includes an input port 41, a first output port 42, a second output port 43, a third output port 44, and a fourth output port 45.
Further, the first unequal-width three-wire coupling structure 11 includes a first coupling wire 111, a second coupling wire 112, and a third coupling wire 113; the second unequal-width three-wire coupling structure 12 comprises a fourth coupling wire 121, a fifth coupling wire 122 and a sixth coupling wire 123; the first coupled line 111 is the same size as the third coupled line 113, the fourth coupled line 121 and the sixth coupled line 123; the second coupling line 112 and the fifth coupling line 122 have the same size; the first coupling line 111 and the second coupling line 112 have different sizes.
Further, the first stepped impedance branch 21 includes a first transmission line 211, a second transmission line 212; the second stepped-impedance branch 22 comprises a third transmission line 221 and a fourth transmission line 222; the first transmission line 211 and the third transmission line 221 have the same size, and the second transmission line 212 and the fourth transmission line 222 have the same size.
Further, the input port 41 is connected to the lower end of the first transmission line 211, the upper end of the first transmission line 211 is connected to the left end of the second transmission line 212, and the right end of the second transmission line 212 is open-circuited.
Further, the input port 41 is connected to the upper end of the third transmission line 221, the lower end of the third transmission line 221 is connected to the left end of the fourth transmission line 222, and the right end of the fourth transmission line 222 is open-circuited.
Further, the input port 41 is connected to the left end of the second coupled line 112, and the right end of the second coupled line 112 is connected to the upper end of the third bridging resistor 33. The input port 41 is connected to the left end of the fifth coupled line 122, and the right end of the fifth coupled line 122 is connected to the lower end of the third bridging resistor 33.
Further, the left end of the first coupling line 111 is connected to the upper end of the first bridging resistor 31, and the right end is connected to the first output port 42; the left end of the third coupling line 113 is connected to the lower end of the first crossover resistor 31, and the right end is connected to the second output port 43.
Further, the left end of the fourth coupling line 121 is connected to the upper end of the second cross-over resistor 32, and the right end is connected to the third output port 44; the left end of the sixth coupling line 123 is connected to the lower end of the second bridging resistor 32, and the right end is connected to the fourth output port 45.
Further, the first transmission line 211 and the third transmission line 221 are high impedance transmission lines, and the impedance value Z iss1Greater than 120 Ω; the second transmission line 212 and the fourth transmission line 222 are low impedance transmission line impedance values Zs2Less than 50 omega.
Further, the electrical length theta of the unequal-width three-wire coupling structure 1 is equal to pi/2 at the central frequency; the electrical length θ of the first transmission line 2111And the electrical length theta of the second transmission line 2122Both at the center frequency are pi/2.
Further, the resistance values of the first bridging resistor 31 and the second bridging resistor 32 are both less than 200 Ω; the third bridge resistor 33 has a resistance value larger than 400 Ω; the first coupled line 111 is wider than the second coupled line 112 with a line width ratio greater than 10: 1.
Fig. 2 shows an even-even mode equivalent circuit under the odd-even mode analysis of the miniaturized broadband four-way filtering power divider based on the unequal-width three-wire coupling structure. Wherein Zs1Is the characteristic impedance, Z, of the first transmission line 211s2Is the characteristic impedance of the second transmission line 212; theta1Is the electrical length, θ, of the first transmission line 2112Is the electrical length of the second transmission line 212, theta is the electrical length of the non-constant width three-wire coupled structure 1, ZsRepresenting the matched impedance of the input port 41. Parameter of
Figure BDA0003020834760000071
Represents the odd-even mode impedance of the asymmetric parallel coupled line formed by the first coupled line 111 and the second coupled line 112; wherein the upper subscript a represents the first coupled line 111, b represents the second coupled line 112; and satisfy the conditions
Figure BDA0003020834760000072
Fig. 3 shows an even-odd mode equivalent circuit of the miniaturized broadband four-way filtering power divider based on the unequal-width three-wire coupling structure under the odd-even mode analysis. The structure in the figure shows that the second coupled line 112 is equivalently grounded at both ends, and the circuit body is an asymmetric parallel coupled line formed by the first coupled line 111 and the second coupled line 112. Wherein R is1Representing the impedance value of the first crossover resistor 31.
Fig. 4 shows an odd-even mode equivalent circuit of the miniaturized broadband four-way filtering power divider based on the unequal-width three-wire coupling structure under the odd-even mode analysis. R2Is the resistance value of the third bridge resistor 33.
Fig. 5 shows an odd-odd mode equivalent circuit of the miniaturized broadband four-way filtering power divider based on the unequal-width three-wire coupling structure under the odd-even mode analysis.
By solving the related parameters by using the impedance matrix of the multiport network and the transmission line theory according to the transmission characteristics of the broadband filtering power divider and the circuit structure and the transmission line parameters of the equivalent circuit shown in fig. 2, fig. 3, fig. 4 and fig. 5, the design formula of the miniaturized four-path broadband filtering power divider of the invention can be obtained, and the solving steps are as follows:
for simple analysis, the circuit is firstly split by adopting an odd-even mode analysis method, port input impedance under various modes is solved, and then a design method of multi-port standard S parameters is combined to finally obtain specific design parameters of the circuit.
Step 1: the circuit analysis was performed on the even-even mode equivalent circuit using the transmission line theory based on the characteristic impedance and the electrical length in fig. 2.
The input impedance of the stepped impedance open stub is:
Figure BDA0003020834760000081
the local circuit input impedance is:
Figure BDA0003020834760000082
wherein
Figure BDA0003020834760000083
K is an adjustable coefficient, and 0< K <1
The input impedance expression of the even-even mode equivalent circuit input port 41 is:
Figure BDA0003020834760000091
step 2: the odd-even mode equivalent circuit is analyzed using the transmission line theory and the impedance analysis method according to the input impedance and the electrical length of the equivalent circuit shown in fig. 4.
The input impedance of the first output port (42) in this mode is:
Figure BDA0003020834760000092
wherein
Figure BDA0003020834760000093
And step 3: the odd-odd mode equivalent circuit was analyzed using transmission line theory and impedance analysis based on the input impedance and electrical length of the equivalent circuit shown in fig. 5. The odd-odd mode equivalent circuit of fig. 5 is identical to the even-odd mode equivalent circuit of fig. 2, so that both circuits analyze one of them.
In fig. 5, the impedance matrix of the two-port network terminating the short-circuited asymmetric parallel coupled lines formed by the first coupled line 111 and the second coupled line 112 is:
Figure BDA0003020834760000094
wherein
Figure BDA0003020834760000095
Figure BDA0003020834760000096
The input impedance of the first output port 42 in the odd-odd mode is:
Figure BDA0003020834760000097
and 4, step 4: solving transmission line parameters in the structure according to a standard scattering parameter matrix
S11=S11ee
Figure BDA0003020834760000101
Figure BDA0003020834760000102
Figure BDA0003020834760000103
Figure BDA0003020834760000104
The matched impedance of the input port 41 is ZsFirst input and outputThe impedance matching of the output port 42, the second output port 43, the third output port 44 and the fourth output port 45 is ZLThe relevant S parameters can be obtained:
Figure BDA0003020834760000105
Figure BDA0003020834760000106
Figure BDA0003020834760000107
the condition of matching all ports and isolating the output ports is satisfied to obtain
S11ee=S22oe=S22oo=0
While satisfying the initial conditions
Figure BDA00030208347600001010
Electrical length theta ═ theta1=θ2Equal to pi/2 at the center frequency, the adjustable factor K is 0.5. According to the design index of the broadband power divider, the particle swarm optimization algorithm is adopted to enable the target relative bandwidth to be more than 60%, and the bandwidth meeting the requirement can be obtained
Figure BDA00030208347600001011
And Zs1、Zs2
And 5: according to the procedure described in step 4, push-out
Figure BDA0003020834760000108
Figure BDA0003020834760000109
The initial resistance of the cross-over resistor can be determined by the aboveThe formula (II) is obtained. Adjusting the resistance R of the cross-over resistor according to the isolation design requirement of the power divider1、R2To achieve good isolation.
In the embodiment of the invention, the center frequency f of the miniaturized four-path broadband filtering power divider0Is 1.5 GHz. From the above design formula and solving step, the values of the circuit parameters of this embodiment can be obtained, as shown in table 1.
TABLE 1 specific circuit parameter values for this example
Figure BDA0003020834760000111
The technical indexes adopted by the embodiment of the invention are as follows:
center frequency: 1.5GHz
15-dB return loss bandwidth in passband: > 80%
Inter-output port isolation >15dB bandwidth: > 80%
The port output amplitude imbalance is less than 0.5dB bandwidth: > 90%
15-dB stop band bandwidth: > 80%
Circuit size:
Figure BDA0003020834760000112
as shown in fig. 6, in the miniaturized wideband four-way filter power divider based on the unequal-width three-wire coupling structure, the relative bandwidth of the input port with the return loss greater than 15dB is 88%, and the passband frequency range is 860MHz to 2.18 GHz. The insertion loss 6.07 + -0.5 dB relative bandwidth is 94.6%, corresponding to a frequency range of 820MHz to 2.24 GHz. At 1.7f0To 2.52f0Achieves an upper stop band suppression effect of about 20dB over the frequency range of (a). The miniaturized broadband four-way filtering power divider based on the non-equal-width three-wire coupling structure has good input port matching performance, achieves the effect of broadband filtering power division and has the capability of upper stop band suppression.
As shown in fig. 7, in the miniaturized wideband four-way filter power divider based on the non-equal-width three-wire coupling structure, the relative bandwidth of the output port with return loss greater than 15dB is 82%, which corresponds to the frequency range from 880MHz to 2.11 GHz. The relative bandwidth with output port return loss greater than 20dB is about 66.7%. The filtering power divider provided by the invention has wider output port matching bandwidth.
As shown in fig. 8, the isolation between the output ports of the same coupling line of the miniaturized wideband four-way filtering power divider based on the non-equal-width three-line coupling structure provided by the present invention is less than-15 dB in the full frequency band. The relative bandwidth of the isolation between the output ports of different coupled lines is larger than 15dB, and the relative bandwidth is 84 percent, and corresponds to the frequency of 870MHz to 2.13 GHz.
The size of the miniaturized broadband four-way filter power divider body based on the non-equal-width three-wire coupling structure is 0.25 lambdag×0.27λgWherein λ isgIs the waveguide wavelength corresponding to a center frequency of 1.5 GHz. The circuit structure of the invention is compact, and the miniaturization is effectively realized.
The above description is only for the preferred embodiment of the present invention, but the scope of the present invention is not limited thereto, and any person skilled in the art should be considered to be within the technical scope of the present invention, and the technical solutions and the inventive concepts thereof according to the present invention should be equivalent or changed within the scope of the present invention.

Claims (5)

1. A miniaturized broadband four-way filtering power divider based on a non-equal-width three-wire coupling structure is characterized by comprising: the non-equal-width three-wire coupling structure, the terminal open-circuit stepped impedance stub, the bridging resistor and the input/output port;
the unequal-width three-wire coupling structure comprises a first unequal-width three-wire coupling structure (11) and a second unequal-width three-wire coupling structure (12), and the circuit sizes of the first unequal-width three-wire coupling structure (11) and the second unequal-width three-wire coupling structure (12) are the same; the open-ended ladder impedance branch comprises a first ladder impedance branch (21) and a second ladder impedance branch (22), the first ladder impedance branch (21) and the second ladder impedance branch (22) are identical in circuit size, the bridge resistor comprises a first bridge resistor (31), a second bridge resistor (32) and a third bridge resistor (33), the first bridge resistor (31) and the second bridge resistor (32) are identical in resistance value, the first bridge resistor (31) and the third bridge resistor (33) are different in resistance value, and the input/output port comprises an input port (41), a first output port (42), a second output port (43), a third output port (44) and a fourth output port (45);
the first unequal-width three-wire coupling structure (11) comprises a first coupling wire (111), a second coupling wire (112) and a third coupling wire (113), the second unequal-width three-wire coupling structure (12) comprises a fourth coupling wire (121), a fifth coupling wire (122) and a sixth coupling wire (123), the first coupling wire (111) is the same as the third coupling wire (113), the fourth coupling wire (121) and the sixth coupling wire (123) in size, the second coupling wire (112) is the same as the fifth coupling wire (122) in size, and the first coupling wire (111) is different from the second coupling wire (112) in size;
the first stepped impedance branch (21) comprises a first transmission line (211) and a second transmission line (212), the second stepped impedance branch (22) comprises a third transmission line (221) and a fourth transmission line (222), the first transmission line (211) and the third transmission line (221) are the same in size, and the second transmission line (212) and the fourth transmission line (222) are the same in size;
the input port (41) is connected with the lower end of the first transmission line (211), the upper end of the first transmission line (211) is connected with one end of the second transmission line (212), and the other end of the second transmission line (212) is open-circuited;
the input port (41) is connected with the upper end of a third transmission line (221), the lower end of the third transmission line (221) is connected with one end of a fourth transmission line (222), and the other end of the fourth transmission line (222) is open-circuited;
the input port (41) is connected with one end of a second coupling line (112), the other end of the second coupling line (112) is connected with the upper end of a third bridging resistor (33), the input port (41) is connected with one end of a fifth coupling line (122), and the other end of the fifth coupling line (122) is connected with the lower end of the third bridging resistor (33);
one end of the first coupling line (111) is connected with the upper end of a first bridging resistor (31), and the other end of the first coupling line (111) is connected with a first output port (42); one end of the third coupling line (113) is connected with the lower end of the first bridging resistor (31), and the other end of the third coupling line (113) is connected with the second output port (43);
one end of the fourth coupling line (121) is connected with the upper end of the second bridging resistor (32), and the other end of the fourth coupling line (121) is connected with the third output port (44); one end of the sixth coupling line (123) is connected with the lower end of the second bridging resistor (32), and the right end of the sixth coupling line (123) is connected with the fourth output port (45).
2. The miniaturized broadband four-way filter power divider based on the unequal-width three-wire coupling structure according to claim 1, wherein: is provided with Zs1Is a characteristic impedance, Z, of the first transmission line (211) and the third transmission line (221)s2Is a characteristic impedance of the second transmission line (212) and the fourth transmission line (222), theta is an electrical length of the first unequal-width three-wire coupling structure (11) and the second unequal-width three-wire coupling structure (12), and theta is an electrical length of the second unequal-width three-wire coupling structure (11)1Is the electrical length, theta, of the first transmission line (211) and the third transmission line (221)2Is the electrical length, R, of the second transmission line (212) and the fourth transmission line (222)1Is a resistance value of the first bridge resistor (31) and the second bridge resistor (32), R2Is the resistance value of the third bridge resistor (33); zsRepresents the matched impedance, Z, of the input port (41)LRepresenting the matched impedance of the first output port (42), the second output port (43), the third output port (44) and the fourth output port (45), the S parameter formula under the odd-even mode analysis method is as follows:
Figure FDA0003020834750000021
Figure FDA0003020834750000022
Figure FDA0003020834750000023
wherein
Figure FDA0003020834750000024
Figure FDA0003020834750000031
Figure FDA0003020834750000032
Resistance R1、R2The solving formula of (2) is as follows:
Figure FDA0003020834750000033
Figure FDA0003020834750000034
in the above formula, Zins、Z11、Z14、Z41、Z44、Z1、Z2、Z3、Z4、Z5、Z6And Z7Is an intermediate variable expressed as follows
Figure FDA0003020834750000035
Figure FDA0003020834750000036
Figure FDA0003020834750000041
K is an adjustable coefficient, and 0<K<1, parameter of
Figure FDA0003020834750000042
Represents the odd-even mode impedance of the asymmetric parallel coupling line formed by the first coupling line (111) and the second coupling line (112); wherein the upper corner mark a represents a first coupled line (111) and the upper corner mark b represents a second coupled line (112), and the condition is satisfied
Figure FDA0003020834750000043
3. The miniaturized broadband four-way filter power divider based on the unequal-width three-wire coupling structure according to claim 1, wherein: the first transmission line (211) and the third transmission line (221) are high impedance transmission lines, the impedance value Zs1Greater than 120 Ω; the second transmission line (212) and the fourth transmission line (222) have a low impedance transmission line impedance value Zs2Less than 50 omega.
4. The miniaturized broadband four-way filter power divider based on the unequal-width three-wire coupling structure according to claim 1, wherein: the electrical length theta of the non-uniform width three-wire coupling structure (1) is equal to pi/2 at the central frequency; an electrical length θ of the first transmission line (211)1And the electrical length theta of the second transmission line (212)2Both at the center frequency are pi/2.
5. The miniaturized broadband four-way filter power divider based on the unequal-width three-wire coupling structure according to claim 1, wherein: the resistance values of the first bridging resistor (31) and the second bridging resistor (32) are both less than 200 omega; the resistance value of the third bridging resistor (33) is greater than 400 omega; the first coupled line (111) is wider than the second coupled line (112) with a line width ratio greater than 10: 1.
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Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN113964467A (en) * 2021-10-25 2022-01-21 金陵科技学院 Balance-unbalanced type in-phase filtering power divider based on three-wire coupling

Citations (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN204651446U (en) * 2015-05-26 2015-09-16 华南理工大学 A kind of balance filter adopting coupling minor matters to load resonator
CN106785289A (en) * 2016-12-26 2017-05-31 西安电子科技大学 Gao Gongfen based on three line coupled structures compares broadband power divider
CN108417956A (en) * 2018-03-28 2018-08-17 杭州电子科技大学 A kind of four road power splitters
CN110247147A (en) * 2019-07-09 2019-09-17 电子科技大学 A kind of micro-strip band logical power splitter
CN110931932A (en) * 2019-12-10 2020-03-27 大连海事大学 Balance/unbalance power divider with any power dividing ratio and design method thereof
CN111384534A (en) * 2020-02-28 2020-07-07 南京智能高端装备产业研究院有限公司 Three-way band-pass power division filter
CN111710945A (en) * 2020-06-08 2020-09-25 南通大学 Subminiature balanced three-wire coupling filter
CN111786062A (en) * 2020-08-04 2020-10-16 大连海事大学 Balanced/unbalanced power divider/combiner with unbalanced-end non-reflection filtering characteristic
CN112018482A (en) * 2020-08-20 2020-12-01 南京航空航天大学 Ultra-wideband filtering power divider based on stepped impedance multimode resonator

Patent Citations (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN204651446U (en) * 2015-05-26 2015-09-16 华南理工大学 A kind of balance filter adopting coupling minor matters to load resonator
CN106785289A (en) * 2016-12-26 2017-05-31 西安电子科技大学 Gao Gongfen based on three line coupled structures compares broadband power divider
CN108417956A (en) * 2018-03-28 2018-08-17 杭州电子科技大学 A kind of four road power splitters
CN110247147A (en) * 2019-07-09 2019-09-17 电子科技大学 A kind of micro-strip band logical power splitter
CN110931932A (en) * 2019-12-10 2020-03-27 大连海事大学 Balance/unbalance power divider with any power dividing ratio and design method thereof
CN111384534A (en) * 2020-02-28 2020-07-07 南京智能高端装备产业研究院有限公司 Three-way band-pass power division filter
CN111710945A (en) * 2020-06-08 2020-09-25 南通大学 Subminiature balanced three-wire coupling filter
CN111786062A (en) * 2020-08-04 2020-10-16 大连海事大学 Balanced/unbalanced power divider/combiner with unbalanced-end non-reflection filtering characteristic
CN112018482A (en) * 2020-08-20 2020-12-01 南京航空航天大学 Ultra-wideband filtering power divider based on stepped impedance multimode resonator

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
YU-ANN LAI等: "A Compact Ka-Band Planar Three-Way Power Divider", 《IEEE MICROWAVE AND WIRELESS COMPONENTS LETTERS》 *

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN113964467A (en) * 2021-10-25 2022-01-21 金陵科技学院 Balance-unbalanced type in-phase filtering power divider based on three-wire coupling
CN113964467B (en) * 2021-10-25 2022-05-17 金陵科技学院 Balance-unbalanced type in-phase filtering power divider based on three-wire coupling

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