Strip line high-power combiner

Abstract

The utility model belongs to the technical field of microwave power sources, and particularly relates to design and application of a strip line high-power combiner. The overall shape of the synthesizer is rectangular, and the synthesizer comprises eight coaxial inputs, one coaxial output, a synthesizer cavity, a polytetrafluoroethylene support column and a three-stage T-shaped synthesis network based on strip lines, the eight paths of coaxial inputs are arranged on one side of the synthesizer cavity, the one path of coaxial output is arranged on the corresponding side of the synthesizer cavity, and the three-stage T-shaped synthesis network based on the strip line is arranged in the synthesizer cavity and is supported and connected through the polytetrafluoroethylene support column; the strip line high-power combiner designed by the utility model has the beneficial effects of high isolation, high power capacity, low insertion loss, simplified processing technology, good heat dissipation performance and the like, and an efficient and reliable power synthesis solution is provided for the field of microwave power sources.

Description

Technical Field

[0001] The invention belongs to the technical field of microwave power sources, and in particular relates to the design and application of a stripline high-power synthesizer. Background Art

[0002] In the field of microwave power sources, especially high-power solid-state microwave sources, in order to achieve high-power output, it is usually necessary to synthesize the output powers of multiple microwave power devices; the power synthesizer is a key microwave network unit to complete this function, and its main design requirements include high-efficiency high-power synthesis capability and maintaining good isolation between various microwave power devices; traditional high-power synthesizers, such as Wilkinson type, coupled ring bridge type, branch bridge type, 3dB directional coupler, etc., have many limitations in achieving good isolation of each input port; for example, the Wilkinson type synthesizer has an isolation resistor connected across the two output arms and is suspended to the ground, so its power-bearing capacity is limited and it is not suitable for high-power synthesis; while the branch bridge type and 3dB directional coupler need to add isolation terminals, isolation resistors, etc. to achieve better isolation effects, which not only increases the complexity of the process, but also increases the processing cost. Summary of the invention

[0003] The present invention aims to design a high-power synthesizer based on strip lines to solve the problem of poor isolation between input ports of traditional synthesizers without isolating loads, while simplifying the processing technology, reducing device costs, and improving synthesis efficiency and power capacity.

[0004] The technical solution adopted by the present invention is: a stripline high-power synthesizer, the overall shape of the synthesizer is rectangular, including: 8 coaxial inputs, 1 coaxial output, a synthesizer cavity, a polytetrafluoroethylene support column, and a 3-level T-type synthesizing network based on the stripline; the 8 coaxial inputs are on one side of the synthesizer cavity, the 1 coaxial output is on the corresponding side of the synthesizer cavity, and the 3-level T-type synthesizing network based on the stripline is arranged inside the synthesizer cavity and supported and connected by the polytetrafluoroethylene support column.

[0005] The radio frequency signals of the eight input ports of the eight-way coaxial input are of equal amplitude and phase, and the inner conductor of the coaxial input port is inserted into the input port of the T-type network.

[0006] The internal stripline of the 8-in-1 synthesizer is mainly composed of 4 first-level T-type networks, 2 second-level T-type networks, and 1 third-level T-type network.

[0007] The arms ① and ② of the first-stage T-type network are input signal ends, which are connected to the inner conductor of the coaxial input end.

[0008] The impedances of the two arms ① and ② are 50Ω strip lines respectively. The electrical lengths of the two arms are required to be consistent, and the lengths can be adjusted according to the structure of the synthesizer.

[0009] The combined output terminal's No. ③ arm of the two 1st - stage T - type networks are respectively connected to the No. ① and No. ② arms of the 2nd - stage T - type network in sequence; the No. ① and No. ② arms of the 2nd - stage T - type network structure are both 50Ω strip lines.

[0010] The combined output terminal's No. ③ arm of the two 2nd - stage T - type networks are respectively connected to the No. ① and No. ② arms of the 3rd - stage T - type network in sequence;

[0011] The No. ① and No. ② arms of the 3rd - stage T - type network structure are both 50Ω strip lines, the impedance of the No. ③ arm strip line is 35.35Ω, the impedance of the No. ④ arm strip line is 50Ω, and the No. ④ arm is connected to the inner conductor of the coaxial output terminal of the synthesizer.

[0012] The synthesizer cavity is realized by adopting a double - layer air - plate line structure, and the connection between its upper and lower air - plate lines is realized through vertical transition, and the vertical transition adopts a cylindrical polytetrafluoroethylene support.

[0013] The radius of the polytetrafluoroethylene support column is 5mm, and the length of the strip lines of the No. ③ arm of the first - stage synthesis network and the No. ①, No. ②, and No. ③ arms of the 2nd - stage and 3rd - stage synthesis networks is 258.5mm.

[0014] The beneficial effects of the present invention are as follows: The strip - line high - power synthesizer designed by the present invention has beneficial effects such as high isolation, high power capacity, low insertion loss, simplified processing technology, and good heat dissipation performance, providing an efficient and reliable power synthesis solution for the microwave power source field. The specific beneficial effects are as follows:

[0015] By adopting multi - stage impedance transformation and the design of strip lines with an electrical length of 90 degrees, the present invention realizes a relatively high isolation between input channels, without the need for additional isolation loads, simplifies the structure, reduces costs, and improves the performance of the synthesizer at the same time; the isolation of each port is better than - 17.9dB, effectively reducing the mutual interference between channels; the synthesizer designed by the present invention can withstand high peak power, with a peak power greater than 200kW and an average power greater than 20kW, meeting the application requirements of high - power microwave sources and having a wide application prospect; by optimizing the structure of the synthesizer and the length of the strip lines, the present invention realizes a lower insertion loss, with an insertion loss less than 0.1dB, improving the synthesis efficiency and reducing power loss; the present invention does not require complex isolation ends and isolation loads, simplifies the processing technology of the synthesizer, reduces the processing cost, and improves the production efficiency and reliability; through reasonable design of the strip - line thickness and cavity height, the present invention has good heat dissipation performance while ensuring high power capacity. When bearing an average power of 20kW, the maximum temperature rise of the synthesizer is 78℃, ensuring the long - term stable operation of the synthesizer. Description of the Drawings

[0016] Figure 1It is a schematic diagram of the external structure of the high-power synthesizer in the present invention.

[0017] Figure 2 It is the internal structure of the high-power synthesizer in the present invention.

[0018] Figure 3 It is a schematic diagram of the structure of the first-stage T-network in the present invention.

[0019] Figure 4 It is a schematic diagram of the structure of the second-stage T-network in the present invention.

[0020] Explanation of the reference numerals in the attached drawings: 1 - coaxial output terminal, 2 - synthesizer cavity, 3 - coaxial input terminal, 4 - polytetrafluoroethylene support post, 5 - T-type synthesis network. Detailed implementation manners

[0021] The following describes in detail the specific implementation manners of the present invention with reference to the drawings of the specification:

[0022] As Figures 1-4 shown, the present invention has successfully designed a stripline high-power synthesizer, achieving high-power and high-efficiency synthesis, while maintaining the mutual isolation of each microwave power device, without the need for isolation loads and water-cooling plates, etc., simplifying the processing technology and reducing the device cost.

[0023] Specific embodiment 1: This embodiment describes the specific implementation process of an 8-in-1 high-power synthesizer based on stripline, mainly including the following steps:

[0024] Component preparation and assembly: Prepare 8 coaxial input terminals (3), with the RF signals of each input port being equal in amplitude and in-phase, and the characteristic impedance being 50Ω; prepare 1 coaxial output terminal (1), with the characteristic impedance being 50Ω; prepare a synthesizer cavity (2), made of aluminum alloy 6061 material, designed as a double-layer air-board line structure; prepare polytetrafluoroethylene support posts (4), with a radius of 5mm, for realizing the vertical transition between the upper and lower layers of air-board lines; prepare a 3-stage T-type synthesis network (5) based on stripline, and the stripline is made of brass H62 material.

[0025] Assembly of the stripline synthesis network: Insert the inner conductors of the 8 coaxial input terminals into the ① and ② arms of the first-stage T-network (5), and the impedances of these two arms are striplines of 50Ω, with the electrical lengths being the same, and connect them to one side of the synthesizer cavity (2); connect the two synthesis output terminals ③ arms of the first-stage T-network (5) to the ① and ② arms of the second-stage T-network (5), and the impedances of these two arms are striplines of 50Ω, and the impedance of the ③ arm is 35.35Ω.

[0026] Connect the two combined output terminals, i.e., the ③ arms, of the second - stage T - type network (5) to the ① and ② arms of the third - stage T - type network (5). The impedances of these two arms are 50Ω strip lines, the impedance of the ③ arm is 35.35Ω, the impedance of the ④ arm is 50Ω, and they are connected to the inner conductor of the coaxial output terminal (1).

[0027] Size adjustment and optimization: According to the structure of the synthesizer, adjust the electrical lengths of the ① and ② arms to be consistent; set the length of the strip line of the ③ arm of the first - stage synthesis network and the ①, ②, and ③ arms of the second - and third - stage synthesis networks to be 258.5mm, corresponding to a wavelength with an electrical length of 90 degrees; through optimization by CST software, determine that the radius of the polytetrafluoroethylene support post (4) is 5mm and the dimensions of the vertical transition.

[0028] Performance test: Conduct a performance test on the synthesizer to ensure that the isolation between input ports is better than - 17.9dB and the average insertion loss is less than 0.1dB; ensure that the synthesizer can withstand a peak power greater than 200kW and an average power greater than 20kW.

[0029] Specific embodiment 2: This embodiment details the implementation process of another 8 - in - 1 high - power synthesizer based on strip lines, including the following steps:

[0030] Component preparation: Prepare 8 coaxial input terminals (3) to ensure that the RF signals are of equal amplitude and in - phase, with a characteristic impedance of 50Ω; prepare 1 coaxial output terminal (1) with a characteristic impedance of 50Ω; prepare a synthesizer cavity (2) made of aluminum alloy 6061 with a double - layer air - plate line structure design; prepare polytetrafluoroethylene support posts (4) for vertical transition with a radius set to 5mm; prepare a three - stage T - type synthesis network (5) of strip lines made of brass H62.

[0031] Assemble the strip - line synthesis network: Insert the inner conductors of the 8 coaxial input terminals into the ① and ② arms of the four T - type networks (5) in the first stage. The impedances of these two arms are 50Ω strip lines and their electrical lengths are the same; connect the two combined output terminals, i.e., the ③ arms, of the first - stage T - type network (5) to the ① and ② arms of the two T - type networks (5) in the second stage. The impedances of these two arms are 50Ω strip lines and the impedance of the ③ arm is 35.35Ω; connect the two combined output terminals, i.e., the ③ arms, of the second - stage T - type network (5) to the ① and ② arms of the one T - type network (5) in the third stage. The impedances of these two arms are 50Ω strip lines, the impedance of the ③ arm is 35.35Ω, the impedance of the ④ arm is 50Ω, and they are connected to the inner conductor of the coaxial output terminal (1).

[0032] Size optimization: According to the specific structure of the synthesizer, adjust the electrical lengths of the two arms ① and ② to ensure consistency; through optimization with CST software, set the strip line length of the ③rd arm of the first-stage synthesis network and the ①st, ②nd, and ③rd arms of the second-stage and third-stage synthesis networks to 258.5 mm, corresponding to a wavelength with an electrical length of 90 degrees; determine the radius of the polytetrafluoroethylene support column (4) to be 5 mm and optimize the size of the vertical transition.

[0033] Performance test and verification: Conduct performance tests on the synthesizer to ensure that the isolation between input ports is better than -17.9 dB and the average insertion loss is less than 0.1 dB; verify that the synthesizer can withstand a peak power greater than 200 kW and an average power greater than 20 kW, meeting the design requirements.

[0034] In summary, through the adoption of multi-stage impedance transformation and the strip line design with an electrical length of 90 degrees, the present invention realizes the efficient synthesis of high-power microwave signals, while maintaining a high port isolation and a low synthesis loss, having significant technical advantages and application values.

Claims

1. A strip-line high-power synthesizer, characterized in that: The overall shape of the synthesizer is rectangular and includes: 8 coaxial inputs, 1 coaxial output, a synthesizer cavity, polytetrafluoroethylene support columns, and a 3-stage T-type synthesis network based on stripline; the 8 coaxial inputs are on one side of the synthesizer cavity, the 1 coaxial output is on the corresponding side of the synthesizer cavity, and the 3-stage T-type synthesis network based on stripline is arranged inside the synthesizer cavity and is supported and connected by polytetrafluoroethylene support columns.

2. The strip line high-power combiner according to claim 1, characterized in that: The RF signals of the 8 input ports of the 8 coaxial inputs are of equal amplitude and in-phase, and the inner conductor of the coaxial input port is inserted into the input port of the T-type network.

3. A stripline high-power combiner according to claim 1, characterized in that: The stripline inside the 8-in-1 synthesizer mainly consists of 4 first-stage T-type networks, 2 second-stage T-type networks, and 1 third-stage T-type network.

4. The strip line high power combiner according to claim 3, characterized in that: The ① and ② arms of the first-stage T-type network are input signal terminals and are connected to the inner conductor of the coaxial input terminal.

5. A stripline high-power combiner according to claim 4, characterized in that: The impedances of the ① and ② arms are striplines of 50Ω respectively, and the electrical lengths of these two arms are required to be the same, and the length can be modulated according to the structure of the synthesizer.

6. The stripline high-power combiner according to claim 3, characterized in that: The synthesis output terminals ③ arms of the 2 first-stage T-type networks are sequentially connected to the ① and ② arms of the second-stage T-type network respectively; the ① and ② arms of the second-stage T-type network structure are striplines of 50Ω respectively.

7. A stripline high-power synthesizer according to claim 3, characterized in that: The synthesis output terminals ③ arms of the 2 second-stage T-type networks are sequentially connected to the ① and ② arms of the third-stage T-type network respectively.

8. A stripline high-power combiner according to claim 1, characterized in that: The synthesizer cavity is realized by a double-layer air plate line structure, and the connection between the upper and lower layers of the air plate line is realized by vertical transition, and the vertical transition uses a cylindrical polytetrafluoroethylene support.

9. The strip line high-power combiner according to claim 8, characterized in that: The radius of the polytetrafluoroethylene support column is 5mm, and the length of the stripline of the ③ arm of the first-stage synthesis network and the ①, ②, and ③ arms of the second-stage and third-stage synthesis networks is 258.5mm.

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