CN219610716U - Coplanar waveguide power divider and synthesizer with arbitrary power ratio - Google Patents

Abstract

The utility model discloses a coplanar waveguide power divider and synthesizer with any power ratio; wherein the splitter is characterized by comprising a phase shifter, a 3dB bridge and an equal power splitter; the input end of the equal power divider is used for receiving the output power of one microwave power source and dividing the output power into two paths of equal amplitude and same phase outputs; one output end of the equal power divider is connected with the input end of the phase shifter through a waveguide, and the other output end of the equal power divider is connected with the first input end of the 3dB bridge through a waveguide; the output end of the phase shifter is connected with the second input end of the 3dB bridge; the phase shifter is used for adjusting the phase of the input power so as to control the difference value of the phase of the input power at two input ends of the 3dB bridge; the utility model also designs a synthesizer matched with the distributor and used for synthesizing two input powers, and the synthesizer comprises a first phase shifter, a second phase shifter, a 3dB bridge and an equal power synthesizer. The utility model reduces complexity and cost of waveguide power divider and synthesizer with arbitrary power ratio to a great extent.

Description

Coplanar waveguide power divider and synthesizer with arbitrary power ratio

Technical Field

The utility model belongs to the technical field of particle accelerators, and relates to a coplanar waveguide power divider and synthesizer with any power ratio.

Background

The charged particle energy in a particle accelerator is derived from the accelerating electric field, while klystrons are typically used as a microwave power source for the accelerator. At present, taking an S-band klystrons as an example, the peak power of the output is generally in the order of tens of megawatts, and according to the requirements of different accelerators, the power of the S-band klystrons is provided for a plurality of accelerating tubes through a microwave transmission system (a high-power high-vacuum environment generally adopts a waveguide) so as to lift the energy of charged particles passing through the tubes. Microwave power which is not used for accelerating charged particles in the accelerating tube is absorbed by a dry load at an output end and converted into heat which is taken away by constant-temperature water. Currently mainstream accelerating tubes can utilize approximately 2/3 of the input power, with the remaining 1/3 being absorbed by the dry load at the output, which means that each klystron is not effectively utilized with about 1/3 of the microwave power. It is well known that the procurement and operating costs of klystrons are considerable, and there is a considerable proportion of the construction and operating costs of accelerators, if 1/3 of the microwave power that is not being used effectively can be recycled, the number of klystrons required can be reduced by about 1/4. And also means that there is no need to use a relatively high dry load in the waveguide device, whereas the waveguide is a passive device, low cost, long life and no need for additional maintenance. In a comprehensive view, the recycling of the microwave power at the output end of the accelerating tube can effectively reduce the construction and operation cost of the accelerator, and accords with the national policy guidance for reducing energy consumption.

The method solves the recycling of microwave power at the output end of the accelerating tube, mainly transmits the power to a certain place through a waveguide, and then synthesizes two paths of microwave power (multiplexing can be cascaded). In other applications, it is desirable that a single microwave power can be simultaneously distributed to two paths of devices in any proportion as required, and both paths of power can be continuously variable between 0 and 1 (0 represents no power in the path, 1 represents the whole power in the path, but the sum of the two paths of power does not exceed 1), which is essentially to realize any power ratio output of the single microwave power. Because of the reciprocity of the waveguide devices, the design methods of the two are identical.

After the 21 st century, various new structures and methods have grown endlessly, but have been changed in many ways. In terms of structures like microstrip lines or strip lines, the ronad-lunian of the american EMS technology company in 2006 introduced several topological structures of variable power splitters in principle, and introduced several design steps and principles of variable power splitters for planar microstrip line-like scenarios (refer to ronad l-lunian, "variable power splitters", publication No. CN 1720636 a). In China, shen Yongchun, wang Wei, etc., phase shift is realized by utilizing variable capacitors and variable stub lengths, respectively, so that variable power ratios are realized in the strip line structure (refer to Shen Yongchun, etc., an utility model patent of a variable power divider, CN 205303636U; wang Wei, a novel power divider design, national microwave millimeter wave conference treatises, all, china, pp.373-375,2001). However, microstrip and stripline structures have limited power capacity and cannot be used in high power environments.

In the waveguide structure, the Rolf Kich et al in the United states in 2001 changes the rectangular waveguide structure at two ends into a single end aiming at the problem of long longitudinal length of the structure, a short-circuit surface is added at the other end of the circular waveguide, and microwave phase shift is realized in the circular waveguide through a slow wave structure, so that variable power ratio output is realized. Since the rectangular waveguide at one end is eliminated and reflection is used instead of transmission, shortening of the longitudinal length of the overall structure is successfully achieved (refer to R.Kich, J.M.Barker, "Reflective waveguide variable power divider/combiner", united States Patent, no. us 6181221 B1,January 2001), but a circular waveguide is still required. In 2002, U.S. hous airlines proposed a waveguide variable power divider based on transmission, all consisting of rectangular waveguides, and the variable power ratio was achieved by changing the bias field values of two ferrites placed vertically in the middle rectangular waveguide to achieve phase shifting (see R.Ihmels, C.Trammell, "variable power divider/combiner", united States Patent, no. us 6377133 B1,April 2002). The structure proposed by Adam kroaming in the united states in 2017 is also realized by using ferrite, and a Three-terminal junction circulator is used, so that the time ratio of ferrite in the circulator in different magnetization directions is controlled through pulse signals, namely, the time ratio of ferrite in different annular directions is controlled, so that two output ends of the circulator respectively occupy part of the time of output power, which is essentially the time-sharing use of microwave power and is not really a variable power component (refer to U.S. patent document "Three-port variable power divider", no. us 2017/0054193 A1). The use of ferrite materials in the above-described structure increases the difficulty of being used in a high vacuum environment, and also limits its power capacity to be used in a high power environment.

In a configuration using neither a circular waveguide nor ferrite material, george Harris in the united states proposed a rectangular waveguide three-port variable power divider in 2006, the metal matching posts of the three ports achieve impedance matching, and the microwave power ratio obtained at the two output ends is adjusted by changing the length of the metal probe extending into the waveguide in the middle of the broad sides of the waveguides of the two output ports (refer to "Apparatus and method for in-process high power variable power division", no. us 2006/0006959 A1). Zhang Hongtao et al in 2012 proposed a broadband waveguide variable power divider, wherein both input and output adopt coaxial line structures, coaxial and waveguide interconversion is realized inside a rectangular waveguide through metal steps, and the distance between two coaxial connectors at the output end is unchanged and can move along the wide side of the waveguide, so as to realize variable power ratio (refer to a broadband waveguide variable power divider, and the utility model patent document of publication No. CN 202121047U). However, in both configurations, the metal probe limits the power capacity and the coaxial connector adds to the structural complexity.

From the research situation of the variable power divider at home and abroad, the purpose is to phase shift microwave power whether the variable power divider uses variable capacitance in similar microstrip lines or introduces an adjustable mechanical part in a waveguide structure or changes the bias magnetic field value of ferrite materials. Therefore, the core of the variable waveguide power divider is to realize the waveguide phase shifter which has simple structure, stable operation, high transmission efficiency, large power capacity and can be used in a high vacuum environment, and the best scheme is realized by adding an adjustable mechanical part in a straight waveguide structure, so that the phase shift can be completed while the waveguide is transmitted without adding an additional port.

In the aspect of waveguide phase shifters, extensive researches are also carried out at home and abroad, and the implementation methods are mainly divided into the following categories: the waveguide phase shifter is designed based on a circular polarizer, and the circular polarizer is used for conversion between rectangular waveguides and circular waveguides, and consists of two rectangular waveguide ports and one circular waveguide port, when the circular polarizer is used as the waveguide phase shifter, microwave power is input from one end of the rectangular waveguide and is transmitted to the circular waveguide, the output end of the circular waveguide is short-circuited, the polarization direction of the circular polarized wave is changed due to a short-circuited surface, the reflected microwave power is transmitted to the other rectangular waveguide port and is output, and the microwave phase can be changed by using a movable short-circuited piston in the circular waveguide to play the role of the waveguide phase shifter (refer to L.T.Guo, C.Chao, W.H.Huang, design of a novel phase shifter for high power microwave applications, proceedings of IEEE International Vacuum Electronics Conference, beijin, china and April 2015; and patent literature of publication No. CN 109818114A entitled "compact high-power capacity waveguide phase shifter and waveguide phase shifting method").

Secondly, the waveguide phase shifter realized by utilizing the self characteristic of the four-port device of the 3dB bridge is characterized in that the microwave power of the two output ends of the 3dB bridge is always equal in amplitude and has a phase difference of 90 DEG, if the microwave reflected back to the input end is offset by 180 DEG after short circuit, the microwaves reflected to the original isolation end (fourth port) are overlapped in phase, and therefore, the microwave phase shifter only needs to be arranged at the two output endsThe function of waveguide phase shifters is achieved by reflecting power using a movable shorting piston or metal post (ref L.P.Lopez, J.L.Masa-Campos, j.a. Ruiz-Cruz, "Design of a reconfigurable rectangular waveguide phase shifter with metallic posts", proceedings of the 47) ^th European Microwave Conference,Nuremberg,Germany,October,2017)。

In addition, the propagation constant of the internal microwave is changed by changing the size of the waveguide or partially filling the medium in the waveguide, so that the phase shift is realized. Other methods capable of achieving microwave phase shifting within the waveguide also include: the telescopic metal structure is introduced into the center of the wide edge inside the waveguide along the axis, or ferrite material is introduced into the waveguide, and even a photosensitive material which is well contacted with the waveguide wall is paved on the inner wall of the waveguide, the resistance of the photosensitive material is changed through illumination, and then the propagation constant of microwaves is changed to realize the phase shift.

However, the above methods are not preferred or can not be used as alternative when the waveguide power divider with any power ratio is designed for the first time in the utility model: the circular polarizer and the 3dB bridge are used as waveguide phase shifters, and can meet the requirements of high-power high-vacuum environment and transmission efficiency, but the introduced additional ports can cause the increase of structural complexity. Changing the dimensions of the waveguide itself or filling the medium inside the waveguide increases the processing complexity of the waveguide, reduces the working stability, and the telescopic metal structure added in the center of the broadside inside the waveguide requires a large longitudinal space, and limits its application. As for ferrite or photosensitive materials, the method is directly contrary to the application requirements of high-power high-vacuum environment.

The utility model patent of application number 202110191601.5, namely a waveguide power distribution and synthesis method, primarily solves the problems, but the two output ports of the adopted magic T are not coplanar, so that the subsequent waveguide connection is complex, and the system processing cost is high.

Disclosure of Invention

Aiming at the problems existing in the prior art, the utility model aims to provide a coplanar waveguide power divider and combiner with any power ratio.

The technical scheme of the utility model is as follows:

the coplanar waveguide power divider with any power ratio is characterized by comprising a phase shifter, a 3dB bridge and an equal power divider;

the input end of the equal power divider is used for receiving the output power of one path of microwave power source and dividing the received input power into two paths of equal-amplitude and same-phase outputs; one output end of the equal power divider is connected with the input end of the phase shifter through a waveguide, and the other output end of the equal power divider is connected with the first input end of the 3dB bridge through a waveguide;

the output end of the phase shifter is connected with the second input end of the 3dB bridge; the phase shifter is used for adjusting the phase of the input power so as to control the difference value of the phase of the input power of the two input ends of the 3dB bridge;

the two output ends of the 3dB bridge are used for being connected with two paths of downstream power consumption equipment.

The coplanar waveguide power combiner with any power ratio is characterized by comprising a first phase shifter, a second phase shifter, a 3dB bridge and an equal power combiner;

a first input end of the 3dB bridge is connected with an output end of the first phase shifter through a waveguide, and a second input end of the 3dB bridge is connected with an input port through the waveguide and is used for receiving one path of microwave power to be synthesized; the first output end of the 3dB bridge is connected with the input end of the second phase shifter through a waveguide, and the second output end of the 3dB bridge is connected with one input end of the equal power combiner through a waveguide; the output end of the second phase shifter is connected with the other input end of the equal power synthesizer through a waveguide; the output end of the equal power synthesizer is used for being connected with downstream power-consuming equipment;

the first phase shifter is used for adjusting the phase of the input power so as to control the difference value of the phase of the input power of the two input ends of the 3dB bridge; the input end of the first phase shifter is used for receiving the microwave power to be synthesized in the second path;

the second phase shifter is used for adjusting the phase of the input power so that the phases of the two paths of input power of the equal power combiner are the same;

the equal power synthesizer is used for synthesizing the two input powers and outputting the synthesized power.

The utility model has the following advantages:

the utility model realizes the coplanar waveguide power divider and synthesizer with any power ratio based on the 3dB bridge, and the system complexity and the processing cost of the waveguide power divider and synthesizer with any power ratio are greatly reduced because the 3dB bridge is of a coplanar structure.

Drawings

Fig. 1 is a block diagram of a 3dB bridge.

Fig. 2 is a schematic diagram of an arbitrary power ratio waveguide power splitter based on a 3dB bridge.

Fig. 3 is a three-dimensional schematic diagram of an arbitrary power ratio waveguide power splitter based on a 3dB bridge.

Fig. 4 is a schematic diagram of a waveguide power combiner based on a 3dB bridge at any power ratio.

Fig. 5 is a three-dimensional schematic of a waveguide power combiner based on a 3dB bridge at any power ratio.

Fig. 6 is a simulation result of a waveguide power combiner with arbitrary power ratio.

Fig. 7 is a graph comparing theoretical and simulation results of a waveguide power divider with arbitrary power ratio.

Reference numerals: 1-phase shifter, 2-equal power divider, 3-3dB bridge, 4-waveguide, 5-first phase shifter, 6-second phase shifter, 7-equal power combiner.

Detailed Description

The utility model will now be described in further detail with reference to the accompanying drawings, which are given by way of illustration only and are not intended to limit the scope of the utility model.

The structure of the 3dB bridge (also called as a 3dB power divider) is shown in fig. 1, the 3dB bridge is of a coplanar structure, waveguides after passing through the 3dB bridge are still in the same plane, the subsequent waveguide connection and installation are very convenient, the number of waveguide devices of the whole power distribution and synthesis device can be greatly reduced, the complexity of the system is effectively reduced, the processing cost of the system is obviously reduced, and meanwhile, the space requirement for the integral installation of the system is also greatly reduced.

Schematic diagrams and three-dimensional schematic diagrams of arbitrary power ratio waveguide power dividers based on 3dB bridges are shown in fig. 2 and 3 in detail. The single-path input power is input into the equal power divider 2 from the port 1, and is then evenly distributed into two paths of equal-amplitude in-phase output power by the equal power divider 2. One path of output power is transmitted from the A1 to the A2 through the common waveguide 4 and is used as the input of the phase shifter 1. The phase shifter 1 is used for changing the phase of the path power (but not changing the amplitude of the path power), and the path power after the phase change is output at A3 and transmitted to A4 through a common waveguide 4 as a first path input of the 3dB bridge 3. The other output power of the equal power divider is transmitted from B1 to B2 via the common waveguide 4 as a second input to the 3dB bridge 3. Thus, the first input of the 3dB bridge 3 at A4 is equal in magnitude to the second input at B2, but with a certain phase difference (the magnitude of this phase difference is controlled by the phase shifter 1). Only this phase difference needs to be controlled to achieve an arbitrary power ratio at the output port 2 and the output port 3 of the 3dB bridge 3.

The schematic diagram and the three-dimensional schematic diagram of the waveguide power combiner with arbitrary power ratio based on the 3dB bridge are shown in fig. 4 and 5 in detail. The first path of input power at the port 1 is output from the A1 after being phase-shifted by the first phase shifter 5, and is transmitted to the A2 through the common waveguide 4 to be used as the first path of input of the 3dB bridge 3. The second input power at port 2 is then directly input to 3dB bridge 3 as the second input to 3dB bridge 3. By shifting the phase of the first phase shifter 5, the phase of the first input and the second input of the 3dB bridge 3 is different by 0 ° or 180 °, and two output powers with equal amplitude but different phases can be obtained at the outputs B1 and C1 of the 3dB bridge 3, regardless of the power-amplitude ratio of the first input of the 3dB bridge 3 at the A2 and the second input at the port 2. The output power of the 3dB bridge 3 at the B1 is transmitted to the B2 via the common waveguide 4, and is used as the input of the second phase shifter 6, and after the second phase shifter 6 performs appropriate phase shifting on the power (the phase of the power at the B4 and the power at the C2 are required to be ensured to be the same through appropriate phase shifting), the output power is output from the B3 of the second phase shifter 6, is transmitted to the B4 via the common waveguide 4, and is used as the first input of the equal power combiner 7. The output power of the 3dB bridge 3 at C1 is transferred via the common waveguide 4 to C2 as a second input to the equal power combiner 7. The equal power combiner 7 is used for combining the first path of input power at B4 and the second path of input power at C2 into one path of power (the equal amplitude and the same phase of the power at B4 and the power at C2) and outputting the power at the port 3. This achieves a final combination of the two input powers of arbitrary power ratio.

Theoretical derivation and simulation of the utility model

1) Theoretical formula derivation (implementation scheme feasibility demonstration of coplanar arbitrary power ratio waveguide power divider and synthesizer based on 3dB bridge):

based on the port definition of fig. 1, assume port 1 inputs microwaves asPort 2 inputs microwaves asThe outputs of port 3 and port 4 are of the following formulas (E and->Amplitude and phase of the input microwaves respectively):

if E ₁ ＝αE ₂ Wherein alpha E (0, + -infinity), and let E ₂ ＝1.

Simultaneous commandAnd θ is the phase difference of the microwaves input from port 1 and port 2, equations (1) and (2) become:

the auxiliary angle formula is used to calculate the modulus of formulas (3) and (4) and make them equal, and then there are

Equation (5) can be simplified as:

2α×sinθ＝-2α×sinθ，α∈(0,+∞) (6)

the condition for the constant establishment of the formula (6) is sin θ≡0, that is, θ=0° or 180 °.

This means: when sin θ≡0, i.e., θ=0° or 180°, the input power ratio for any of ports 1 to 21:1 power division (out of phase) outputs of port 3 and port 4 can be achieved. Then, only one of the outputs is required to be phase-shifted, and then an equal-power synthesizer is matched, so that the final synthesis of two microwave powers with any input power ratio can be completed. A waveguide power combiner for any input power ratio is shown in the schematic diagram of fig. 4.

Meanwhile, if the input microwave power amplitudes of the port 1 and the port 2 are equal, only one phase difference θ exists, namely: e (E) ₁ ＝αE ₂ (α=1) andsubstituting the values into the formulas (3) and (4) and using an auxiliary angle formula to calculate a modulus value and simplify the modulus value, the ratio of the output microwave power amplitude values of the port 3 and the port 4 is as follows:

as can be seen, whenWhen the value range of the formula (7) is (0, ++) namely if an equal power divider is used for equally dividing a certain path of microwave power and outputting the same amplitude and the same phase, only one path of microwave power is required to be subjected to phase shift within 180 degrees, then two paths of microwaves with different equal amplitude and the same phase are input into the port 1 and the port 2 of the 3dB bridge, the output with any power ratio can be realized at the port 3 and the port 4 of the 3dB bridge, and the distribution of any proportion of single path of microwave power is realized, and the implementation principle diagram is shown in figure 2.

2) Computer simulation:

a) Simulation verification of waveguide power combiner with arbitrary power ratio:

modeling the 3dB bridge shown in FIG. 1 in software, setting the phase difference between the input port 1 and the port 2 to be 0 degree (in phase) and the amplitude ratio to be changed from 0.01 to 100, wherein the output amplitude ratio of the port 3 to the port 4 is constant to be 1:1, and the conclusion of the formula (6) is consistent. The simulation results are shown in fig. 6, and it should be noted that the output amplitude ratio of port 3 to port 4 in the simulation results is within 1.5 ppm of the theoretical value 1:1, mainly due to the slight difference between the physical simulation model of the 3dB bridge and the ideal condition assumed during theoretical derivation. In practical simulation, since the number of grids cannot be infinite (so that the simulation error can only approach but cannot be 0), the ports of the 3dB bridge cannot be perfectly matched, and cannot be perfectly isolated.

b) Simulation verification of arbitrary power ratio waveguide power splitter:

the amplitude ratio of the input port 1 to the port 2 in fig. 1 is set to be 1:1 (constant amplitude) in software, the phase difference is changed from-90 degrees to 90 degrees, and the proportion of the output amplitude of the port 4 to the total output is continuously variable from 100 to 0 percent at the moment, so that the conclusion of the formula (7) is consistent. The simulation results are shown in fig. 7.

The feasibility of the waveguide power distribution and synthesizer with any power ratio based on the 3dB bridge is verified on theoretical derivation and simulation, and the theoretical formula result is completely consistent with the simulation result; the utility model realizes the coplanarity of waveguide power distribution and synthesizer with any power ratio, and greatly reduces the complexity of the system and the processing cost.

Although specific embodiments of the utility model have been disclosed for illustrative purposes, it will be appreciated by those skilled in the art that the utility model may be implemented with the help of a variety of examples: various alternatives, variations and modifications are possible without departing from the spirit and scope of the utility model and the appended claims. Therefore, it is intended that the utility model not be limited to the particular embodiment disclosed as the best mode contemplated for carrying out this utility model, but that the utility model will have the scope indicated by the scope of the appended claims.

Claims (2)

1. The coplanar waveguide power divider with any power ratio is characterized by comprising a phase shifter, a 3dB bridge and an equal power divider;

the input end of the equal power divider is used for receiving the output power of one path of microwave power source and dividing the received input power into two paths of equal-amplitude and same-phase outputs; one output end of the equal power divider is connected with the input end of the phase shifter through a waveguide, and the other output end of the equal power divider is connected with the first input end of the 3dB bridge through a waveguide;

the output end of the phase shifter is connected with the second input end of the 3dB bridge; the phase shifter is used for adjusting the phase of the input power so as to control the difference value of the phase of the input power of the two input ends of the 3dB bridge;

the two output ends of the 3dB bridge are used for being connected with two paths of downstream power consumption equipment.

2. The coplanar waveguide power combiner with any power ratio is characterized by comprising a first phase shifter, a second phase shifter, a 3dB bridge and an equal power combiner;

a first input end of the 3dB bridge is connected with an output end of the first phase shifter through a waveguide, and a second input end of the 3dB bridge is connected with an input port through the waveguide and is used for receiving one path of microwave power to be synthesized; the first output end of the 3dB bridge is connected with the input end of the second phase shifter through a waveguide, and the second output end of the 3dB bridge is connected with one input end of the equal power combiner through a waveguide; the output end of the second phase shifter is connected with the other input end of the equal power synthesizer through a waveguide; the output end of the equal power synthesizer is used for being connected with downstream power-consuming equipment;

the first phase shifter is used for adjusting the phase of the input power so as to control the difference value of the phase of the input power of the two input ends of the 3dB bridge; the input end of the first phase shifter is used for receiving the microwave power to be synthesized in the second path;

the second phase shifter is used for adjusting the phase of the input power so that the phases of the two paths of input power of the equal power combiner are the same;

the equal power synthesizer is used for synthesizing the two input powers and outputting the synthesized power.