A waveguide-microstrip four-way power divider
By inserting two microstrip probes on the wide side of the rectangular waveguide and connecting the microstrip lines, the problem of difficult to achieve four-channel power distribution in the prior art is solved, and the power distribution of four-channel microstrip lines is realized, which is suitable for electronic systems such as communications and radars.
Patent Information
- Application Number
- CN202411275265.2
- Authority / Receiving Office
- CN · China
- Patent Type
- Patents(China)
- Current Assignee / Owner
- Filing Date
- 2024-09-12
- Publication Date
- 2025-07-18
- Estimated Expiration
- 2044-09-12
AI Technical Summary
The existing rectangular waveguide-microstrip power distributors can only realize two-channel power distribution, which is difficult to meet the engineering design requirements of four-channel power distribution output.
Insert two microstrip probes on the wide side of the rectangular waveguide, connect the microstrip lines through the dielectric substrate to achieve four-way power distribution output, and set an isolation resistor on the dielectric substrate to improve isolation performance.
It realizes the power distribution of four microstrip lines, has good insertion loss, return loss, isolation characteristics and phase consistency, and is suitable for electronic systems such as communications and radars.
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Figure CN118920061B_ABST
Abstract
Description
Technical Field
[0001] The present invention relates to the technical field of radio frequency and microwave circuits, and particularly to a waveguide-microstrip four-way power divider. Background Art
[0002] A power divider is a multi-port microwave device that can divide the input power into two or more equal or unequal power outputs, or synthesize multiple microwave signals with different powers into one output. As an important passive device, it has a wide range of applications in electronic systems such as communication, radar, and electronic countermeasure.
[0003] The rectangular waveguide has the characteristics of high power capacity and low insertion loss, while the microstrip line, as a planar circuit, is easy to integrate with microwave integrated circuits with other functions. Both of them, as two common types of circuit structures in engineering, have a large number of applications. The existing rectangular waveguide-microstrip power divider adopts an implementation scheme of inserting a microstrip probe or a coupling loop inside the rectangular waveguide, which has the advantages of a compact circuit structure, low insertion loss, and being convenient for integrating with other functional circuits at the back end of the power distribution output. However, its power division types are mainly the electrical excitation method of inserting a total of 2 microstrip probes at the centers of the two wide sides of the rectangular waveguide, or on the wide sides on the same side of the rectangular waveguide, or the magnetic excitation method of inserting a total of 2 ring-shaped circuits at the centers of the two narrow sides of the rectangular waveguide to realize the circuit structure of two-way power division of the input power. Under certain design requirements, the above settings cannot meet the circuit structure of four-way power division output. Summary of the Invention
[0004] In view of this, an embodiment of the present invention provides a waveguide-microstrip four-way power divider, which can realize four-way power division output on the wide side of the rectangular waveguide to meet the requirements of some engineering designs.
[0005] The present invention provides a waveguide-microstrip four-way power divider, including:
[0006] A first rectangular waveguide;
[0007] A dielectric substrate, connected to the cross-section at the end of the signal transmission direction of the first rectangular waveguide;
[0008] Two insertion circuits, arranged on the surface of the dielectric substrate. The two insertion circuits respectively extend into the first rectangular waveguide from the two wide sides of the first rectangular waveguide and are symmetrically arranged with respect to the central connection line of the two narrow sides of the first rectangular waveguide. The insertion circuit includes two strip-shaped microstrip probes, and the output ends of the strip-shaped microstrip probes are connected with microstrip lines.
[0009] In an alternative embodiment, the two strip microstrip probes of the insertion circuit are symmetrically arranged with respect to the central connection line of the two wide sides of the first rectangular waveguide.
[0010] In an alternative embodiment, a second rectangular waveguide is further included. The second rectangular waveguide is short-circuited at the terminal and is connected to the back surface of the dielectric substrate, and the cross-sectional dimensions of the second rectangular waveguide are the same as those of the first rectangular waveguide.
[0011] In an alternative embodiment, a first isolation resistor is provided between the subsequent circuits of the two strip microstrip probes of the same insertion circuit, and the first isolation resistor is assembled on the dielectric substrate in the outer cavity wall groove on the wide side of the first rectangular waveguide.
[0012] In an alternative embodiment, a second isolation resistor is provided between the subsequent circuits of the two adjacent strip microstrip probes of the two insertion circuits, and the second isolation resistor is assembled on the dielectric substrate in the outer cavity wall groove on the narrow side of the first rectangular waveguide.
[0013] In an alternative embodiment, the microstrip line includes an impedance transformation line segment connected to the output end of the strip microstrip probe.
[0014] In an alternative embodiment, the microstrip line further includes an output end standard microstrip line connected to the impedance transformation line segment.
[0015] In an alternative embodiment, four channel structures are further included for the dielectric substrate carrying the strip microstrip probes to pass through the waveguide from the first rectangular waveguide. The four channel structures are formed on the outer cavity wall of the first rectangular waveguide and are communicated with the inside of the first rectangular waveguide.
[0016] In an alternative embodiment, the characteristic impedance of the standard microstrip line is 50 ohms.
[0017] In an alternative embodiment, the material of the dielectric substrate is Rogers5880 and the thickness is 0.254 mm.
[0018] A waveguide-microstrip four-way power divider provided by an embodiment of the present application inserts two strip microstrip probes on the two wide sides of a first rectangular waveguide respectively. After the four strip microstrip probe circuits are led out through the two wide sides of the first rectangular waveguide, four-way microstrip line power distribution output is realized to meet the requirements of some engineering designs. BRIEF DESCRIPTION OF THE DRAWINGS
[0019] Figure 1 The figure shows a three-dimensional structural schematic diagram of a waveguide-microstrip four-way power divider;
[0020] Figure 2Shown is a schematic diagram of the front - side circuit on the dielectric substrate of a four - way power divider;
[0021] Figure 3 Shown is a schematic diagram of the back - side circuit on the dielectric substrate of a four - way power divider;
[0022] Figure 4 Shown is a simulation result diagram of the input return loss and insertion loss of the waveguide - microstrip four - way power divider provided by an embodiment of the present invention;
[0023] Figure 5 Shown is a simulation result diagram of the output return loss of the waveguide - microstrip four - way power divider provided by an embodiment of the present invention;
[0024] Figure 6 Shown is a simulation result diagram of the isolation between the output ports of the waveguide - microstrip four - way power divider provided by an embodiment of the present invention;
[0025] Figure 7 Shown is a simulation result diagram of the phase consistency of the output ports of the waveguide - microstrip four - way power divider provided by an embodiment of the present invention.
[0026] Reference numerals
[0027] 1. First rectangular waveguide; 2. Dielectric substrate; 3. Strip - shaped microstrip probe; 4. Second rectangular waveguide; 5. First isolation resistor; 6. Second isolation resistor; 7. Outer cavity wall groove; 8. Impedance transformation line segment; 9. Standard microstrip line; 10. Channel structure; 11. Metal - free layer region with the same size as the second rectangular waveguide; 12. Copper - plated layer of the dielectric substrate. Detailed implementation manners
[0028] 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. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the protection scope of the present invention.
[0029] A power divider is a multi - port microwave device that can divide the input power into two or more equal or unequal power outputs, or synthesize multiple microwave signals with different powers into one output. As an important passive device, it has a wide range of applications in electronic systems such as communication, radar, and electronic countermeasures.
[0030] Common power dividers mainly include circuit structures such as Wilkinson bridge, Lange bridge, branch - line bridge, T - junction, magic T, etc., and can be implemented in the form of independent or mixed use of various waveguide systems including microstrip line, stripline, coaxial line, CPW, SIW, rectangular waveguide, etc.
[0031] The rectangular waveguide has the characteristics of high power capacity and low insertion loss, while the microstrip line, as a planar circuit, is easy to be integrated with microwave integrated circuits with other functions. As two common types of circuit structures in engineering, both of them have a large number of applications.
[0032] For the existing rectangular waveguide - microstrip power divider, the implementation scheme of inserting a microstrip probe or a coupling loop inside the rectangular waveguide is adopted, which has the advantages of compact circuit structure, low insertion loss, and being convenient for integrating with other functional circuits at the back end of the power distribution output. However, its power division types are mainly the electrical excitation method of inserting a total of 2 microstrip probes at the centers of the two wide sides of the rectangular waveguide, or on the wide sides on the same side of the rectangular waveguide, or the magnetic excitation method of inserting a total of 2 ring-shaped circuits at the centers of the two narrow sides of the rectangular waveguide to realize the circuit structure of two-way power division of the input power. Almost no circuit structure that realizes four-way power distribution output by inserting 2 microstrip probes on the two wide sides inside the input rectangular waveguide is seen in this type of structure.
[0033] In view of the above problems, referring to Figures 1-3 In an embodiment of the present invention, a waveguide - microstrip four-way power divider is provided, including: a first rectangular waveguide 1, a dielectric substrate 2, which is connected to the cross-section at the end of the signal transmission direction of the first rectangular waveguide 1. The two surfaces of the first rectangular waveguide 1 used for the signal transmission direction are defined as the input surface and the output surface. Among the other four surfaces of the first rectangular waveguide 1 except the input surface and the output surface, the surface with a relatively small area is defined as the narrow side, and the surface with a relatively large area is defined as the wide side. The dielectric substrate 2 is connected to the cross-section at the end of the signal transmission direction of the first rectangular waveguide 1, that is, connected to the output surface of the first rectangular waveguide 1.
[0034] Two insertion circuits are arranged on the surface of the dielectric substrate 2. The two insertion circuits extend into the first rectangular waveguide 1 from the two wide sides of the first rectangular waveguide 1 respectively, and are symmetrically arranged with respect to the central connection line of the two narrow sides of the first rectangular waveguide 1. The insertion circuit includes two strip-shaped microstrip probes 3, and the output ends of the strip-shaped microstrip probes 3 are connected with microstrip lines. That is, on the surface of the dielectric substrate 2 located inside the first rectangular waveguide 1, a total of four strip-shaped microstrip probes 3 are laid. The four strip-shaped microstrip probes 3 are grouped in two as an insertion circuit. The four strip-shaped microstrip probes 3 extend into the first rectangular waveguide 1 from the wide sides of the first rectangular waveguide 1 respectively, and the setting directions of the four strip-shaped microstrip probes 3 are the same as the electric field direction of the main mode TE 10 mode of the first rectangular waveguide 1. The two insertion circuits are symmetrically arranged with respect to the central connection line of the two narrow sides of the first rectangular waveguide 1, that is, the four strip-shaped microstrip probes 3 in the two insertion circuits are arranged in pairs.
[0035] The dielectric substrate 2 is of a plate - type structure. Four strip - shaped microstrip probes 3 and microstrip lines connected to the strip - shaped microstrip probes 3 are laid on the upper surface thereof close to the first rectangular waveguide 1.
[0036] Among them, when the first rectangular waveguide 1 is used as the signal input end, the microstrip line is used as the signal output end, realizing a circuit structure with four - way power distribution output. When the microstrip line is used as the signal input end, the first rectangular waveguide 1 is used as the signal output end, realizing the synthesis of four - way microwave signal power into one - way output.
[0037] Furthermore, the power divider circuit further includes four channel structures 10 through which the dielectric substrate 2 carrying the strip - shaped microstrip probes 3 passes out of the waveguide from the first rectangular waveguide 1. The four channel structures 10 are formed on the outer cavity wall of the first rectangular waveguide 1 and are in communication with the inside of the first rectangular waveguide 1.
[0038] By changing the different positions and physical structure dimensions of the four strip - shaped microstrip probes 3 on the dielectric substrate 2, the usage requirements of a four - way power divider with the same or different output power ratios among the four channels can be realized.
[0039] Furthermore, by integrating other circuits on the dielectric substrate 2, the design and realization of circuit components with more functions can be achieved.
[0040] In an alternative embodiment, referring to Figure 2 , the two strip - shaped microstrip probes 3 of the inserted circuit are symmetrically arranged with respect to the central connection line of the two wide - side edges of the first rectangular waveguide 1.
[0041] In an alternative embodiment, referring to Figure 1 , it further includes a second rectangular waveguide 4 with a short - circuited end. The waveguide cross - sectional dimension of the second rectangular waveguide 4 is the same as that of the first rectangular waveguide 1. It is placed on the back of the dielectric substrate 2. The back of the dielectric substrate 2 of the circuit has a metal - free layer region 11 and a copper - clad layer 12 of the dielectric substrate with the same size as the second rectangular waveguide. The waveguide port of the second rectangular waveguide 4 is accurately docked with the waveguide port of the first rectangular waveguide 1. The first rectangular waveguide 1, the dielectric substrate 2, and the second rectangular waveguide 4 are tightly connected and assembled together.
[0042] The second rectangular waveguide 4 with a short - circuited end is part of the circuit structure of the device for realizing four - way coupled power distribution output. By optimizing the distance between the dielectric substrate 2 and the short - circuit surface of the second rectangular waveguide 4, the best power - distribution output performance can be obtained.
[0043] In an alternative embodiment, referring to Figure 2, between the post-connected impedance transformation line circuits of two strip-shaped microstrip probes 3 connected to the same insertion circuit, a first isolation resistor 5 is provided. The first isolation resistor 5 is assembled on the dielectric substrate 2 in the outer cavity wall groove 7 on the wide side of the first rectangular waveguide 1, and is used to improve the mutual isolation performance between the output channel ports corresponding to the addition of the first isolation resistor 5.
[0044] In an alternative embodiment, referring to Figure 2 , between the post-connected impedance transformation line circuits of two adjacent strip-shaped microstrip probes 3 of the two insertion circuits, a second isolation resistor 6 is provided. The second isolation resistor 6 is assembled on the dielectric substrate 2 in the outer cavity wall groove 7 on the narrow side of the first rectangular waveguide 1, and is used to improve the mutual isolation performance between the output channel ports corresponding to the addition of the second isolation resistor 6.
[0045] In an alternative embodiment, referring to Figure 2 , the microstrip line includes an impedance transformation line segment 8 connected to the output end of the strip-shaped microstrip probe 3.
[0046] In an alternative embodiment, the microstrip line further includes an output end standard microstrip line 9 connected to the impedance transformation line segment 8.
[0047] In an alternative embodiment, referring to Figure 1 、 Figure 2 , the characteristic impedance of the standard microstrip line 9 is 50 ohms.
[0048] In an alternative embodiment, the thickness of the dielectric substrate 2 is 0.254 mm, and its material is Rogers5880.
[0049] In a specific embodiment of the present invention, it is a millimeter-wave waveguide-microstrip four-way power divider. The three-dimensional structure of the four-way power divider and the circuit on the dielectric substrate are as shown in the appendix Figures 1-3 . The dielectric substrate used has a material of Rogers5880 and a thickness of 0.254 mm. The input signal in the Ka band is fed through the first rectangular waveguide 1 at the input end. On the cross-section of the first rectangular waveguide 1 at a certain transmission distance from the input port of the first rectangular waveguide 1, a dielectric substrate 2 is placed. Inside the first rectangular waveguide 1 where the dielectric substrate 2 is located, four strip-shaped microstrip probes 3 are symmetrically arranged in pairs with the central axes of the wide and narrow sides of the first rectangular waveguide 1. The lengths and widths of the four strip-shaped microstrip probes 3 are 1.278 and 0.469 mm respectively. After the four strip-shaped microstrip probes 3 enter the channel structure 10 from the wide side of the first rectangular waveguide 1 respectively, they are connected to the standard microstrip line 9 with a characteristic impedance of 50 ohms through a metal impedance transformation line segment 8 for impedance transformation. Between the impedance transformation line segments 8 of two adjacent paths, a first isolation resistor 5 and a second isolation resistor 6 are added to improve the mutual isolation performance between adjacent output ports of the standard microstrip line 9.
[0050] Reference Figure 4 As shown in Figure 4 , the curves of the input return loss and insertion loss of the millimeter-wave four-way power divider of this embodiment are presented. It can be seen from the figure that in the frequency range of 26.5 - 40 GHz, the average insertion loss is -0.50 dB, and at the center frequency, the insertion loss can reach -0.41 dB; in the frequency range of 26.5 - 40 GHz, the input return loss is greater than 18 dB, and in the frequency range of 26.6 - 39.2 GHz, the input return loss is greater than 19 dB. It can be seen that the millimeter-wave four-way power divider has good input impedance matching and good transmission coefficient.
[0051] Reference Figure 5 As shown in Figure 5 , the curve of the output return loss of the millimeter-wave four-way power divider of this embodiment is presented. It can be seen from the figure that in the frequency range of 26.5 - 40 GHz, the output return loss is greater than 4.2 dB. It can be seen that the millimeter-wave four-way power divider has good output impedance matching.
[0052] Reference Figure 6 As shown in Figure 6 , the curve of the isolation between each output port of the millimeter-wave four-way power divider of this embodiment is presented. It can be seen from the figure that in the frequency range of 26.5 - 38 GHz, the isolation between the output ends on the same side of the waveguide broadside is greater than 13.5 dB, the isolation between the two diagonal output ends of the broadside is greater than 13 dB, and in the frequency range of 26.5 - 40 GHz, the isolation between the adjacent output ends of the waveguide narrow side is greater than 12.5 dB. It can be seen that the millimeter-wave four-way power divider has high isolation characteristics and a relatively wide operating bandwidth.
[0053] Reference Figure 7 As shown in Figure 7 , the curve of the phase consistency of each output port of the millimeter-wave four-way power divider of this embodiment is presented. It can be seen from the figure that in the frequency range of 26.5 - 40 GHz, the phases of the two output ports on the same side of the waveguide broadside are in-phase, with high phase consistency, and the phases of the two output ports on the opposite sides of the waveguide broadside are anti-phase.
[0054] The above are only the preferred embodiments of the present invention, and are not used to limit the present invention. Any modifications, equivalent substitutions, etc. made within the spirit and principles of the present invention shall be included within the protection scope of the present invention.
Claims
1. A waveguide - microstrip four - way power divider, characterized in that, Comprising: A first rectangular waveguide (1); A dielectric substrate (2), connected to the cross-section at the end of the signal transmission direction of the first rectangular waveguide (1); Two insertion circuits, arranged on the surface of the dielectric substrate (2), the two insertion circuits respectively extend into the first rectangular waveguide (1) from the two wide-side edges of the first rectangular waveguide (1), and are symmetrically arranged with respect to the central connection line of the two narrow-side edges of the first rectangular waveguide (1), the insertion circuit includes two strip-shaped microstrip probes (3), and the output end of the strip-shaped microstrip probe (3) is connected with a microstrip line; The two strip-shaped microstrip probes (3) of the insertion circuit are symmetrically arranged with respect to the central connection line of the two wide-side edges of the first rectangular waveguide (1); Between the subsequent circuits of the two strip-shaped microstrip probes (3) of the same insertion circuit, a first isolation resistor (5) is provided, and the first isolation resistor (5) is assembled on the dielectric substrate (2) in the outer cavity wall groove (7) of the wide-side edge of the first rectangular waveguide (1); Between the subsequent circuits of the two adjacent strip-shaped microstrip probes (3) of the two insertion circuits, a second isolation resistor (6) is provided, and the second isolation resistor (6) is assembled on the dielectric substrate (2) in the outer cavity wall groove (7) of the narrow-side edge of the first rectangular waveguide (1); It further includes four channel structures (10) through which the dielectric substrate (2) carrying the strip-shaped microstrip probes (3) passes out of the waveguide from the first rectangular waveguide (1), and the four channel structures (10) are formed on the outer cavity wall of the first rectangular waveguide (1) and are communicated with the inside of the first rectangular waveguide (1).
2. The waveguide - microstrip four - way power divider according to claim 1, wherein It further includes a second rectangular waveguide (4), the second rectangular waveguide (4) is short-circuited at the terminal, connected to the lower surface of the dielectric substrate (2), and the cross-sectional dimension of the second rectangular waveguide (4) is the same as the cross-sectional dimension of the first rectangular waveguide (1).
3. The waveguide-microstrip four-way power divider according to claim 1, wherein The microstrip line includes an impedance transformation line segment (8) connected to the output end of the strip-shaped microstrip probe (3).
4. The waveguide-microstrip four-way power divider according to claim 3, characterized in that, The microstrip line further includes an output end standard microstrip line (9) connected to the impedance transformation line segment (8).
5. The waveguide - microstrip four - way power divider according to claim 4, wherein The characteristic impedance of the standard microstrip line (9) is 50 ohms.
6. The waveguide - microstrip four - way power divider according to claim 1, wherein The material of the dielectric substrate (2) is Rogers5880, and the thickness is 0.254 mm.
Citation Information
Patent Citations
Microstrip-to-waveguide power combiner for radio frequency power combining
US20030197572A1