A filter-type broadband unequal power divider with no reflection at the input port

Abstract

The present invention discloses a filtering-type broadband unequal power divider with no reflection at the input port. The specific scheme comprises: a transmission line, a resonator-loaded coupled line, an absorption branch, an isolation resistor and a 50Ω port; the transmission line comprises a first transmission line and a second transmission line; the resonator-loaded coupled line comprises a first resonator-loaded coupled line and a second resonator-loaded coupled line; the first resonator-loaded coupled line comprises a first section of parallel coupled line and a first section of parallel open line; the second resonator-loaded coupled line comprises a second section of parallel coupled line and a second section of parallel open line; the first section of parallel coupled line comprises a first coupled line and a second coupled line. The present invention provides a filtering-type broadband unequal power divider with no reflection at the input port. The divider has the characteristics of wide bandwidth, good no reflection characteristic at the input port, flat passband, high frequency selectivity, simple structure, easy processing, low cost and the like, and is suitable for wide promotion.

Description

Technical Field

[0001] The invention relates to the field of microwave passive devices, and in particular to a filtering-type broadband unequal power distributor with no reflection at the input port. Background Art

[0002] Power dividers are one of the most widely used passive components in the microwave and millimeter wave fields and are crucial components in radar communication systems. In phased array radar systems, it is often necessary to distribute transmitter energy among the various transmitting units. Power dividers, as essential components, are widely used in power amplifiers, mixers, and antenna arrays. Power dividers are passive microwave networks that split input signal energy into equal or unequal outputs. The Wilkinson power divider, due to its simple structure, is widely used. A key front-end component, the Wilkinson power divider is widely used in many RF / microwave subsystems, such as antenna feed networks and power amplifier circuits, due to its high isolation between its output port and the matching conditions of all ports. With technological advancements, research on unequal power dividers has become increasingly important, especially for antenna array beamforming. Unequal power division feeding can effectively suppress excessive antenna sidelobe levels.

[0003] With the development of modern radio frequency and microwave industries, the requirements for miniaturization, low loss and low cost are becoming increasingly higher. In order to comply with this trend, multifunctional fusion technology has attracted the attention of more and more scholars as an emerging field. The unequal power divider integrates filtering characteristics and non-reflection characteristics on the basis of the unequal power divider, and develops in the direction of wide bandwidth and high selectivity to meet the requirements of modern communication systems. The non-reflection characteristic means that the useless signal reflected back to the source end is absorbed by lossy components, which greatly reduces the signal energy reflected back to the transmitter to achieve the non-reflection characteristic. As far as the author knows, there is currently no non-reflection unequal filtering power divider. The current problems of unequal power dividers include narrow bandwidth, passband flatness, poor frequency selectivity and other problems. To this end, the present invention proposes a filtering-type broadband unequal power divider with non-reflection at the input port, which adds non-reflection characteristics without affecting the performance of the broadband filtering unequal power divider. Summary of the Invention

[0004] In view of the problems existing in the prior art, the present invention discloses a filtering-type broadband unequal power divider with no reflection at the input port, comprising: a transmission line, a resonator-loaded coupling line, an absorption branch, an isolation resistor and a 50Ω port;

[0005] Furthermore, the transmission line includes a first transmission line and a second transmission line; the resonator-loaded coupling line includes a first resonator-loaded coupling line and a second resonator-loaded coupling line; the first resonator-loaded coupling line includes a first parallel coupling line and a first parallel open line; the second resonator-loaded coupling line includes a second parallel coupling line and a second parallel open line; the first parallel coupling line includes a first coupling line and a second coupling line; the first parallel open line includes a first open line and a third transmission line; the second parallel coupling line includes a third coupling line and a fourth coupling line; the second parallel open line includes a second open line and a fourth transmission line; the absorbing branch includes a first absorbing branch and a second absorbing branch; the first absorbing branch includes a first resistor and a fifth transmission line; the second absorbing branch includes a second resistor and a sixth transmission line; the 50Ω transmission line includes a 50Ω port I, a 50Ω port II, and a 50Ω port III;

[0006] Furthermore, the right end of the 50Ω port I is connected to the left end of the first transmission line and the second transmission line; the right end of the first transmission line is connected to the left end of the second coupling line; the right end of the first coupling line is connected to the lower end of the third transmission line and the 50Ω port II; the right end of the second coupling line is connected to the left end of the first resistor, and the right end of the first resistor is connected to the left end of the fifth transmission line; the right end of the fifth transmission line is connected to the floor; the right end of the second transmission line is connected to the left end of the third coupling line; the right end of the third coupling line is connected to the left end of the second resistor, and the right end of the second resistor is connected to the left end of the sixth transmission line; the right end of the sixth transmission line is connected to the floor; the right end of the fourth coupling line is connected to the upper end of the fourth transmission line and the 50Ω port III; the lower end of the fourth transmission line is connected to the upper end of the second open line; the upper end of the isolation resistor is connected to the right end of the first transmission line and the left end of the second coupling line, and the lower end of the isolation resistor is connected to the right end of the second transmission line and the left end of the third coupling line;

[0007] Furthermore, the parameters of the first section of the parallel open line are the same as those of the second section of the parallel open line; the characteristic impedance of the first transmission line is k times the characteristic impedance of the second transmission line. 2 times, where k 2 is the ratio of the output power of port 3 to that of port 2; the difference between the odd and even mode characteristic impedances of the first parallel coupled line is the square root k times the difference between the odd and even mode characteristic impedances of the second parallel coupled line; the first transmission line, the second transmission line, the first parallel coupled line, the second parallel coupled line, the first open line, the third transmission line, the second open line, the fourth transmission line, the fifth transmission line

[0008] The electrical lengths of the first transmission line and the sixth transmission line are the same, and are 90° corresponding to the center frequency point.

[0009] Furthermore, the output port of the said non-reflective filter-type broadband unequal power divider is matched to S22 and S 33 And the isolation between output ports S 23 The expression is as follows:

[0010]

[0011]

[0012]

[0013] The parameters in ABCD can be expressed as:

[0014] A=(A2A 11 +C2A 13 )(A 22 +Y Y A 24 )+(A 11 B2+A 13 D2)+(A 42 +Y Y A 44 )

[0015] B=A 24 (A2A 11 +C2A 13 )+A 44 (B2A 11 +D2A 13 )

[0016] C=A2(A 11 Y Y +A 31 )(A 22 +Y Y A 24 )+C2(A 13 Y Y +A 33 )(A 22 +Y Y A 24 )+B2(A 11 Y Y +A 31 )(A 42 +Y Y A 44 )+D2(A 13 Y Y +A 33 )(A 42 +Y Y A 44 )D=A 24 A2(A 11 Y Y +A 31 )+A24 C2(A 13 Y Y +A 33 )+A 44 B2(A 11 Y Y +A 31 )+A 44 D2(A 13 Y Y +A 33 )

[0017] where Y Y It is the port input and output admittance of the first parallel open line and the second parallel open line.

[0018] The expression is:

[0019]

[0020] Among them A 11 、A 13 、A 31 and A 33 The ABCD matrix of the first parallel coupled line terminated with the first absorbing branch viewed from the 50Ω port II of the power divider is expressed as follows:

[0021] The expressions are:

[0022]

[0023]

[0024]

[0025]

[0026] where R e1 is the input characteristic impedance of the first absorbing branch port, which is expressed as:

[0027] R e1 =R2+jZ5tanθ

[0028] A2, B2, C2, and D2 are the ABCD matrix of the network consisting of the first transmission line, the second transmission line, the first resistor, and the 50Ω port I. Its expression is:

[0029]

[0030] in

[0031]

[0032]

[0033]

[0034]

[0035] A 22 、A 24 、A 42 and A 44 The ABCD matrix of the second parallel coupled line terminated at the second absorbing branch viewed from the left is expressed as follows:

[0036]

[0037]

[0038]

[0039]

[0040] where R e2 is the input characteristic impedance of the second absorbing branch port, which is expressed as:

[0041] R e2 =R 2_2 +jZ 5_5 tanθ

[0042] Where Z1 is the characteristic impedance of the first open line and the second open line, Z2 is the characteristic impedance of the third transmission line and the fourth transmission line, Z3 is the characteristic impedance of the first transmission line, Z4 is the characteristic impedance of the second transmission line, Z5 is the characteristic impedance of the fifth transmission line, and Z 5_5 is the characteristic impedance of the sixth transmission line, Z o1 and Z e1 are the odd-mode characteristic impedance and even-mode characteristic impedance of the first parallel coupled line, Z o2 and Z e2 are the odd-mode characteristic impedance and even-mode characteristic impedance of the second parallel coupled line, Z S is the characteristic impedance of the 50Ω transmission line, R1 is the resistance value of the isolation resistor, R2 and R 2_2 are the resistance values of the first resistor and the second resistor, respectively, and θ is the electrical length of the first transmission line, the second transmission line, the first parallel coupled line, the second parallel coupled line, the first open line, the third transmission line, the second open line, the fourth transmission line, the fifth transmission line, and the sixth transmission line.

[0043] Furthermore, by adjusting the impedance of the fifth and sixth transmission lines and the resistance values of the first and second resistors in the absorption branch, reflection-free characteristics are achieved both in-band and out-of-band at the input port. Unequal power distribution is achieved by adjusting the impedance ratio of the first and second transmission lines, as well as the first and second parallel coupled lines. By adjusting the characteristic impedances of the first open-ended line, the third open-ended line, the second open-ended line, and the fourth transmission line, in-band flatness, frequency selectivity, and matching at the output port are improved. By adjusting the resistance value of the isolation resistor, good isolation is achieved at the output port.

[0044] Furthermore, the characteristic impedances of the third transmission line, the fourth transmission line, the fifth transmission line and the sixth transmission line are all greater than 100Ω; and the characteristic impedances of the first open line, the second open line and the second transmission line are between 40Ω and 80Ω.

[0045] Due to the adoption of the above technical solution, the present invention provides a filtering-type broadband unequal power divider with no reflection at the input port. The input port of the power divider has no reflection characteristics within the entire test frequency band (0-4GHz), that is, the bandwidth of the input port return loss of the power divider is greater than 10-dB is 0-4GHz, and the minimum return loss in the passband is greater than 15dB. The 3-dB relative bandwidth within the band of the 2-port of the power divider is 99% (1.01-2.99GHz), and the 3-dB relative bandwidth within the band of the 3-port is 98% (1.02-2.98GHz). Both output ports have broadband filtering characteristics. At the same time, the power divider also has high frequency selectivity, and its S 21 The rectangular coefficient is K 30dB =1.24, S 31 The rectangular coefficient is K 30dB =1.22. Furthermore, the fractional bandwidth for in-band 2-port output return loss <-10dB reaches 83% (1.17 to 2.83GHz), and the fractional bandwidth for in-band 3-port output return loss <-10dB reaches 89% (1.11 to 2.89GHz). In-band isolation between output ports can reach 19dB. BRIEF DESCRIPTION OF THE DRAWINGS

[0046] In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are only some embodiments recorded in this application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0047] Figure 1 The present invention is a schematic structural diagram of a filtering-type broadband unequal power divider with no reflection at the input port.

[0048] Figure 2 This is an equivalent circuit diagram of the filtering-type broadband unequal power divider with no reflection at the input port described in the present invention.

[0049] Figure 3 This is the S parameter curve of the filter-type broadband unequal power divider with no reflection at the input port of the present invention.

[0050] In the figure: 1, transmission line, 11, first transmission line, 12, second transmission line, 2, resonator-loaded coupled line, 21, first resonator-loaded coupled line, 22, second resonator-loaded coupled line, 211, first parallel coupled line, 212, first parallel open line, 221, second parallel coupled line, 222, second parallel open line, 2111, first coupled line, 2112, second coupled line, 2121, first open line, 2122, Third transmission line, 2211, third coupled line, 2212, fourth coupled line, 2221, second open line, 2222, fourth transmission line, 3, absorption branch, 31, first absorption branch, 32, second absorption branch, 311, first resistor, 312, fifth transmission line, 321, second resistor, 322, sixth transmission line, 5, 50Ω port, 51, 50Ω port I, 52, 50Ω port II, 53, 50Ω port III; DETAILED DESCRIPTION

[0051] To make the objectives, technical solutions, and advantages of the present invention more clearly understood, the present invention will be further described in detail below in conjunction with specific embodiments and with reference to the accompanying drawings. It should be understood that these descriptions are merely exemplary and are not intended to limit the scope of the present invention. In addition, in the following description, descriptions of well-known structures and technologies are omitted to avoid unnecessary confusion of the concepts of the present invention.

[0052] Figure 1 This is a schematic structural diagram of a filtering-type broadband unequal power divider with no reflection at the input port according to the present invention. The reflectionless bandpass filtering unequal power divider of this embodiment may include: a transmission line 1, a resonator-loaded coupling line 2, an absorbing branch 3, an isolation resistor 4, and a 50Ω port 5;

[0053] Furthermore, the transmission line 1 includes a first transmission line 11 and a second transmission line 12; the resonator-loaded coupling line 2 includes a first resonator-loaded coupling line 21 and a second resonator-loaded coupling line 22; the first resonator-loaded coupling line 21 includes a first section of parallel coupling line 211 and a first section of parallel open line 212; the second resonator-loaded coupling line 22 includes a second section of parallel coupling line 221 and a second section of parallel open line 222; the first section of parallel coupling line 211 includes a first coupling line 2111 and a second coupling line 2112; the first section of parallel open line 212 includes a first open line 212 1 and a third transmission line 2122; the second parallel coupled line 221 includes a third coupled line 2211 and a fourth coupled line 2212; the second parallel open line 222 includes a second open line 2221 and a fourth transmission line 2222; the absorbing branch 3 includes a first absorbing branch 31 and a second absorbing branch 32; the first absorbing branch 31 includes a first resistor 311 and a fifth transmission line 312; the second absorbing branch 32 includes a second resistor 321 and a sixth transmission line 322; the 50Ω port 5 includes a 50Ω port I51, a 50Ω port II52, and a 50Ω port III53;

[0054] Furthermore, the right end of the 50Ω port I51 is connected to the left ends of the first transmission line 11 and the second transmission line 12; the right end of the first transmission line 11 is connected to the left end of the second coupling line 2112; the right end of the first coupling line 2111 is connected to the lower end of the third transmission line 2122 and the 50Ω port II52; the right end of the second coupling line 2112 is connected to the left end of the first resistor 311, and the right end of the first resistor 311 is connected to the left end of the fifth transmission line 312; the right end of the fifth transmission line 312 is connected to the floor; the right end of the second transmission line 12 is connected to the left end of the third coupling line 2211; The right end of the third coupled line 2211 is connected to the left end of the second resistor 321, and the right end of the second resistor 321 is connected to the left end of the sixth transmission line 322; the right end of the sixth transmission line 322 is connected to the floor; the right end of the fourth coupled line 2212 is connected to the upper end of the fourth transmission line 2222 and the 50Ω port III53; the lower end of the fourth transmission line 2222 is connected to the upper end of the second open line 2221; the upper end of the isolation resistor 4 is connected to the right end of the first transmission line 11 and the left end of the second coupled line 2112, and the lower end of the isolation resistor 4 is connected to the right end of the second transmission line 12 and the left end of the third coupled line 2211;

[0055] Furthermore, the first section of the parallel open line 212 and the second section of the parallel open line 222 have the same parameters; the characteristic impedance of the first transmission line 11 is k times the characteristic impedance of the second transmission line 12. 2 times, where k 2is the ratio of the output powers of port 3 to port 2; the difference between the odd and even mode characteristic impedances of the first parallel coupled line 211 is the square root k times the difference between the odd and even mode characteristic impedances of the second parallel coupled line 221; the electrical lengths of the first transmission line 11, the second transmission line 12, the first parallel coupled line 211, the second parallel coupled line 221, the first open-circuit line 2121, the third transmission line 2122, the second open-circuit line 2221, the fourth transmission line 2222, the fifth transmission line 312, and the sixth transmission line 322 are all the same and are 90° at the center frequency.

[0056] Specifically, in this example, good matching of the two output ports and good isolation between the two output ports can be achieved. The ABCD matrix analysis method is used to analyze the two output port networks and calculate the circuit parameters.

[0057] Figure 2 The equivalent circuit diagram between the two output ports is given. Y is the port input admittance of the first parallel open-ended line 212 and the second parallel open-ended line 222. Re1 and Re2 are the port input impedances of the first absorption branch 31 and the second absorption branch 32, respectively. 11 、A 13 、A 31 and A 33 is the ABCD matrix parameter of the first parallel coupled line 211 connected to the second absorbing branch 31 as viewed from port 2. A2, B2, C2 and D2 are the ABCD matrix parameters of the network consisting of the first transmission line 11, the second transmission line 12, the first resistor 311 and the 50Ω port I51. 22 、A 24 、A 42 and A 44 It is the ABCD matrix parameter when the second parallel coupling line 221 is connected to the second absorbing branch 32 and viewed from the left.

[0058] according to Figure 2 By solving the relevant parameters of the equivalent circuit structure, the design formula of the filter-type broadband unequal power divider with no reflection at the input port of the present invention can be obtained. The solution steps are as follows:

[0059] Step 1: The solution process of the ABCD matrix of the M1 part looking from the 50Ω port II (52) of the power divider is as follows:

[0060] A1=A 11 B1=A 13 C1=Y Y A 11 +A 31 D1=Y Y A 13 +A 33

[0061]

[0062] The first parallel coupling line 211 is connected to the first absorption branch (ABCD parameter A of 31). 11 、A 13 、A 31 and A 33 Solution process:

[0063]

[0064] Where I4=0,V2 / I2=-R e1 And there are:

[0065]

[0066] Get an A 11 、A 13 、A 31 and A 33 The expression is as follows:

[0067]

[0068]

[0069]

[0070]

[0071] in

[0072] R e1 =R2+jZ5tanθ

[0073] Step 2: The solution process of the ABCD matrix of part M2 is as follows:

[0074]

[0075] in

[0076]

[0077]

[0078]

[0079]

[0080] Step 3: The solution process of the ABCD matrix of the M3 part from the left is as follows:

[0081] A3=A 22 +YY A 24 B3=A 24 C3=A 42 +Y Y A 44 D3=A 44 The ABCD parameter A of the second parallel coupling line 221 connected to the second absorbing branch 32 22 、A 24 、A 42 and A 44 Solution process:

[0082]

[0083] Where I1=0,V3 / I3=-R e2 And there are:

[0084]

[0085] R e2 =R 2_2 +jZ 5_5 tanθ

[0086] Get an A 22 、A 24 、A 42 and A 44 The expression is:

[0087]

[0088]

[0089]

[0090]

[0091] Step 4: The ABCD parameters between two output ports can be expressed as:

[0092] A=(A2A 11 +C2A 13 )(A 22 +Y Y A 24 )+(A 11 B2+A 13 D2)+(A 42 +Y Y A 44 )

[0093] B=A 24 (A2A 11 +C2A 13 )+A 44 (B2A11 +D2A 13 )

[0094] C=A2(A 11 Y Y +A 31 )(A 22 +Y Y A 24 )+C2(A 13 Y Y +A 33 )(A 22 +Y Y A 24 )+B2(A 11 Y Y +A 31 )(A 42 +Y Y A 44 )+D2(A 13 Y Y +A 33 )(A 42 +Y Y A 44 )D=A 24 A2(A 11 Y Y +A 31 )+A 24 C2(A 13 Y Y +A 33 )+A 44 B2(A 11 Y Y +A 31 )+A 44 D2(A 13 Y Y +A 33 )

[0095] Then we can get the output port matching S of the power divider. 22 and S 33 And the isolation between output ports S 23 The expression is as follows:

[0096]

[0097]

[0098]

[0099] In a specific embodiment of the present invention, the center frequency of the non-reflective filter-type broadband unequal power divider at the input port is 2.0 GHz. Figure 3As shown. The input port of the power divider has a non-reflective characteristic within the entire test frequency band (0-4GHz), that is, the bandwidth of the input port return loss of the power divider greater than 10-dB is 0-4GHz, and the minimum return loss in the passband is greater than 15dB. The 3-dB relative bandwidth of the 2-port in-band of the power divider is 99% (1.01-2.99GHz), and the 3-dB relative bandwidth of the 3-port in-band is 98% (1.02-2.98GHz). Both output ports have broadband filtering characteristics. At the same time, the power divider also has high frequency selectivity, and its S21 rectangular coefficient is K 30dB =1.24, S31 rectangular coefficient is K 30dB =1.22. Furthermore, the fractional bandwidth for in-band 2-port output return loss <-10dB reaches 83% (1.17 to 2.83GHz), and the fractional bandwidth for in-band 3-port output return loss <-10dB reaches 89% (1.11 to 2.89GHz). In-band isolation between output ports can reach 19dB.

[0100] The above description is only a preferred specific embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any technician familiar with the technical field, within the technical scope disclosed by the present invention, who makes equivalent replacements or changes based on the technical solution and inventive concept of the present invention, should be covered by the scope of protection of the present invention.

Claims

1. A filter-type broadband unequal power divider with no reflection at the input port, characterized in that include: Transmission line (1), resonator loaded coupling line (2), absorption branch (3), isolation resistor (4) and 50Ω port (5); The transmission line (1) comprises a first transmission line (11) and a second transmission line (12); the resonator-loaded coupling line (2) comprises a first resonator-loaded coupling line (21) and a second resonator-loaded coupling line (22); the first resonator-loaded coupling line (21) comprises a first section of parallel coupling line (211) and a first section of parallel open line (212); the second resonator-loaded coupling line (22) comprises a second section of parallel coupling line (221) and a second section of parallel open line (222); the first section of parallel coupling line (211) comprises a first coupling line (2111) and a second coupling line (2112); the first section of parallel open line (212) comprises a first open line (2121) and a third transmission line line (2122); the second section of parallel coupled line (221) includes a third coupled line (2211) and a fourth coupled line (2212); the second section of parallel open line (222) includes a second open line (2221) and a fourth transmission line (2222); the absorption branch (3) includes a first absorption branch (31) and a second absorption branch (32); the first absorption branch (31) includes a first resistor (311) and a fifth transmission line (312); the second absorption branch (32) includes a second resistor (321) and a sixth transmission line (322); the 50Ω port (5) includes a 50Ω port I (51), a 50Ω port II (52) and a 50Ω port III (53); The 50Ω port I (51) is connected to the left ends of the first transmission line (11) and the second transmission line (12); the right end of the first transmission line (11) is connected to the left end of the second coupling line (2112); the right end of the first coupling line (2111) is connected to the lower end of the third transmission line (2122) and the 50Ω port II (52); the right end of the second coupling line (2112) is connected to the left end of the first resistor (311), and the right end of the first resistor (311) is connected to the left end of the fifth transmission line (312); the right end of the fifth transmission line (312) is connected to the ground; the right end of the second transmission line (12) is connected to the left end of the third coupling line (2211); The right end of the three coupling lines (2211) is connected to the left end of the second resistor (321), and the right end of the second resistor (321) is connected to the left end of the sixth transmission line (322); the right end of the sixth transmission line (322) is connected to the floor; the right end of the fourth coupling line (2212) is connected to the upper end of the fourth transmission line (2222) and the 50Ω port III (53); the lower end of the fourth transmission line (2222) is connected to the upper end of the second open line (2221); the upper end of the isolation resistor (4) is connected to the right end of the first transmission line (11) and the left end of the second coupling line (2112), and the lower end of the isolation resistor (4) is connected to the right end of the second transmission line (12) and the left end of the third coupling line (2211); The first section of the parallel open line (212) and the second section of the parallel open line (222) have the same parameters; the characteristic impedance of the first transmission line (11) is k times the characteristic impedance of the second transmission line (12). 2 times, where k 2 is the ratio of the output powers of the 50Ω port III (53) and the 50Ω port II (52); the difference between the odd and even mode characteristic impedances of the first section of parallel coupled line (211) is square root k times the difference between the odd and even mode characteristic impedances of the second section of parallel coupled line (221); the electrical lengths of the first transmission line (11), the second transmission line (12), the first section of parallel coupled line (211), the second section of parallel coupled line (221), the first open line (2121), the third transmission line (2122), the second open line (2221), the fourth transmission line (2222), the fifth transmission line (312) and the sixth transmission line (322) are all the same and are 90° at the center frequency point.

2. The filter-type broadband unequal power divider with no reflection at the input port according to claim 1, characterized in that: The output port of the power divider matches S 22 and S 33 And the isolation between output ports S 23 The expression is as follows: The parameter expression in ABCD is: <h2 style=";text-align:left;direction:ltr">A=(A2A<h2 style=";text-align:left;direction:ltr"> 11 <h2 style=";text-align:left;direction:ltr"> +C2A<h2 style=";text-align:left;direction:ltr"> 13 <h2 style=";text-align:left;direction:ltr"> (A)<h2 style=";text-align:left;direction:ltr"> 22 <h2 style=";text-align:left;direction:ltr"> +Y<h2 style=";text-align:left;direction:ltr"> Y <h2 style=";text-align:left;direction:ltr"> A<h2 style=";text-align:left;direction:ltr"> 24 <h2 style=";text-align:left;direction:ltr"> )+(A<h2 style=";text-align:left;direction:ltr"> 11 <h2 style=";text-align:left;direction:ltr"> B2+A<h2 style=";text-align:left;direction:ltr"> 13 <h2 style=";text-align:left;direction:ltr"> D2)+(A<h2 style=";text-align:left;direction:ltr"> 42 <h2 style=";text-align:left;direction:ltr"> +Y<h2 style=";text-align:left;direction:ltr"> Y <h2 style=";text-align:left;direction:ltr"> A<h2 style=";text-align:left;direction:ltr"> 44 <h2 style=";text-align:left;direction:ltr"> ) <h2 style=";text-align:left;direction:ltr">B=A<h2 style=";text-align:left;direction:ltr"> 24 <h2 style=";text-align:left;direction:ltr"> (A2A<h2 style=";text-align:left;direction:ltr"> 11 <h2 style=";text-align:left;direction:ltr"> +C2A<h2 style=";text-align:left;direction:ltr"> 13 <h2 style=";text-align:left;direction:ltr"> )+A<h2 style=";text-align:left;direction:ltr"> 44 <h2 style=";text-align:left;direction:ltr"> (B2A<h2 style=";text-align:left;direction:ltr"> 11 <h2 style=";text-align:left;direction:ltr"> +D2A<h2 style=";text-align:left;direction:ltr"> 13 <h2 style=";text-align:left;direction:ltr"> ) C=A2(A 11 AND Y +A 31 )(TO 22 +Y Y TO 24 )+C2(A 13 AND Y +A 33 )(TO 22 +Y Y TO 24 )+B2(A 11 AND Y +A 31 )(TO 42 +Y Y TO 44 )+D2(A 13 AND Y +A 33 )(TO 42 +Y Y TO 44 ) D=A 24 A2(A 11 Y Y +A 31 )+A 24 C2(A 13 Y Y +A 33 )+A 44 B2(A 11 Y Y +A 31 )+A 44 D2(A 13 Y Y +A 33 ) where Y Y are the port input and output admittances of the first parallel open-circuit line (212) and the second parallel open-circuit line (222), and are expressed as follows: Among them A 11 、A 13 、A 31 and A 33 It is the ABCD matrix of the first parallel coupled line (211) connected to the first absorption branch (31) viewed from the 50Ω port II (52) of the power divider, and its expressions are: where R e1 is the input characteristic impedance of the first absorbing branch (31) port, which is expressed as: R e1 =R2+jZ5tanθ A2, B2, C2 and D2 are the ABCD matrix of the network composed of the first transmission line (11), the second transmission line (12), the first resistor (311) and the 50Ω port I (51), and the expression thereof is: in A 22 、A 24 、A 42 and A 44 It is the ABCD matrix of the second parallel coupling line (221) connected to the second absorption branch (32) viewed from the left, and its expressions are: where R e2 is the input characteristic impedance of the second absorbing branch (32) port, which is expressed as: R e2 =R 2_2 +jZ 5_5 tanθ Wherein Z1 is the characteristic impedance of the first open line (2121) and the second open line (2221), Z2 is the characteristic impedance of the third transmission line (2122) and the fourth transmission line (2222), Z3 is the characteristic impedance of the first transmission line (11), Z4 is the characteristic impedance of the second transmission line (12), Z5 is the characteristic impedance of the fifth transmission line (312), and Z 5_5 is the characteristic impedance of the sixth transmission line (322), Z o1 and Z e1 are the odd-mode characteristic impedance and even-mode characteristic impedance of the first parallel coupled line (211), Z o2 and Z e2 are the odd-mode characteristic impedance and even-mode characteristic impedance of the second parallel coupled line (221), Z S is the impedance of the 50Ω port (5), R1 is the resistance value of the isolation resistor (4), R2 and R 2_2 are the resistance values of the first resistor (311) and the second resistor (321), respectively; and θ is the electrical length of the first transmission line (11), the second transmission line (12), the first section of parallel coupled line (211), the second section of parallel coupled line (221), the first open line (2121), the third transmission line (2122), the second open line (2221), the fourth transmission line (2222), the fifth transmission line (312), and the sixth transmission line (322).

3. The filter-type broadband unequal power divider with no reflection at the input port according to claim 1, characterized in that: By adjusting the impedance of the fifth transmission line (312) and the sixth transmission line (322) in the absorption branch (3) and the resistance values of the first resistor (311) and the second resistor (321), the non-reflection characteristics of the input port in-band and out-band are achieved; by adjusting the impedance ratio of the first transmission line (11) and the second transmission line (12) and the first section of parallel coupled line (211) and the second section of parallel coupled line (221), unequal power distribution is achieved; by adjusting the characteristic impedance of the first open line (2121), the third transmission line (2122), the second open line (2221) and the fourth transmission line (2222), the in-band flatness, frequency selectivity and the matching degree of the output port are improved; and by adjusting the resistance value of the isolation resistor (4), the isolation between the output ports is improved.

4. The filter-type broadband unequal power divider with no reflection at the input port according to claim 1, characterized in that: The characteristic impedances of the third transmission line (2122), the fourth transmission line (2222), the fifth transmission line (312) and the sixth transmission line (322) are all greater than 100Ω; the characteristic impedances of the first open line (2121), the second open line (2221) and the second transmission line (12) are between 40 and 80Ω.

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