Tri-filar diaphragm loaded variable polarizer

Abstract

The present invention discloses a three-bend diaphragm loaded polarizer, which aims to solve the defect of low power capacity of existing dielectric plate polarizers and ferrite polarizers. 01 ‑TE 11 It consists of a mode converter and a diaphragm-loaded circular polarizer. 01 ‑TE 11 The circular waveguide section of the mode converter and the diaphragm-loaded circular polarizer is connected. 01 ‑TE 11 The mode converter consists of a first circular waveguide, a first curved circular waveguide, a second curved circular waveguide, a third curved circular waveguide, and a second circular waveguide. A diaphragm-loaded line-circular polarizer is constructed from the third circular waveguide and a metal diaphragm. The metal diaphragm is welded symmetrically along the axis of the third circular waveguide to the inner wall of the third circular waveguide, forming a solid boat-like shape. The present invention boasts high mode conversion efficiency, with a transmission efficiency exceeding 99.5% at the center frequency. The present invention also features a simple structure, easily implements polarization switching, and can achieve gigawatt-level power capacity.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of high-power microwave devices, in particular to a three-bent diaphragm loaded line-to-circular polarizer. BACKGROUND

[0002] High-power microwave (HPM) generally refers to strong electromagnetic radiation with a frequency of 300MHz to 300GHz and a peak power greater than 100MW or an average power greater than 1MW. High-power microwave has various applications, mainly including: high-power pulsed radar, applied to accurately distinguish targets in a wide frequency band; high-energy particle radio frequency accelerator, applied to high-energy physics and nuclear physics research; heating of controlled thermonuclear plasma based on electron cyclotron resonance mechanism and high-power microwave weapons.

[0003] The microwave polarizer is a common device in the field of microwave and millimeter wave technology, which mainly functions to switch between linear polarization, left-handed circular polarization and right-handed circular polarization, and has wide applications in radar systems, communication systems, electronic countermeasure systems and other fields. The performance of these systems is greatly affected by the quality of the microwave polarizer used for polarization tracking of targets. Conventional power capacity polarizers mainly include dielectric plate polarizers and ferrite polarizers. The dielectric plate polarizer uses the separation characteristics of dielectric plates to different directions of incoming waves to realize polarization conversion. Since dielectric materials are introduced, the power capacity is relatively low, less than 100MW, which does not meet the requirements of the high-power microwave field. The ferrite polarizer uses ferrite materials to change the propagation constant of the ferrite material by changing the amplitude of the applied magnetic field or electric field, thereby realizing polarization adjustment. The power capacity of the ferrite polarizer can generally reach one or two hundred kilowatts (X-band) to megawatt (C-S band), which belongs to high-power capacity polarizers. In the field of high-power microwave research, due to the strong electromagnetic field characteristics of high-power microwave devices, the microwave polarizer in the prior art is limited by the power capacity and cannot be truly applied in the field of high-power microwave.

[0004] Therefore, how to provide a new type of high-power microwave polarizer with a power capacity of GW level has been a hot issue in the field. SUMMARY

[0005] The technical problem to be solved by the present application is:

[0006] In view of the defects of low power capacity of the dielectric plate polarizer and the ferrite polarizer in the prior art, a three-bent diaphragm loaded polarizer is provided to realize the switching of linear polarization, left-handed circular polarization and right-handed circular polarization, and the power capacity can reach GW level.

[0007] The technical scheme of the present application is:

[0008] The present application consists of a three-bend TM 01 -TE 11 mode converter and a diaphragm-loaded circular polarizer. The three-bend TM 01 -TE 11 mode converter and a diaphragm-loaded circular polarizer are butt-jointed.

[0009] The three-bend TM 01 -TE 11 mode converter consists of a first circular waveguide, a first curved circular waveguide, a second curved circular waveguide, a third curved circular waveguide and a second circular waveguide. The first circular waveguide is connected to a microwave source at one end as an input port and connected to the first curved circular waveguide at the other end; the first curved circular waveguide is connected to the first circular waveguide at one end and connected to the second curved circular waveguide at the other end; the second curved circular waveguide is connected to the first curved circular waveguide at one end and connected to the third curved circular waveguide at the other end; the third curved circular waveguide is connected to the second curved circular waveguide at one end and connected to the second circular waveguide at the other end; the second circular waveguide is connected to the third curved circular waveguide at one end and connected to the input port of the diaphragm-loaded circular polarizer at the other end as an output port. The end of the circular waveguide and the curved circular waveguide close to the microwave source is defined as the input end, and the end far away from the microwave source is defined as the output end. The first circular waveguide and the second circular waveguide are coaxial.

[0010] The first circular waveguide is made of metal material and is a hollow cylinder with an inner radius of R0, a length of h0 and a thickness of d; the input end of the first circular waveguide is connected to the microwave source, and the output end of the first circular waveguide is connected to the input end of the first curved circular waveguide.

[0011] The first curved circular waveguide is made of metal material and is a curved hollow cylinder with an inner radius of R0, a curvature radius of R1, a bending angle of θ1 and a thickness of d; the input end of the first curved circular waveguide is connected to the output end of the first circular waveguide, and the output end of the first curved circular waveguide is connected to the input end of the second curved circular waveguide.

[0012] The second curved circular waveguide is made of metal material and is a curved hollow cylinder with an inner radius of R0, a curvature radius of R2, a bending angle of θ2 and a thickness of d; the input end of the second curved circular waveguide is connected to the output end of the first curved circular waveguide, and the output end of the second curved circular waveguide is connected to the input end of the third curved circular waveguide.

[0013] The third curved circular waveguide is made of metal material and is a curved hollow cylinder with an inner radius of R0, a curvature radius of R3, a bending angle of θ3 and a thickness of d; the input end of the third curved circular waveguide is connected to the output end of the second curved circular waveguide, and the output end of the third curved circular waveguide is connected to the input end of the second circular waveguide.

[0014] The second circular waveguide is made of metal material, in the form of hollow cylinder, with inner radius R0, length h0 and thickness d; the input end of the second circular waveguide is connected with the output end of the third curved circular waveguide, and the output end is the three-bend TM 01 -TE 11 The output end of the mode converter is connected with the input end of the diaphragm-loaded circular polarizer.

[0015] The diaphragm-loaded linear-circular polarizer is composed of a third circular waveguide and metal diaphragms. The third circular waveguide is made of metal material, in the form of hollow cylinder, with inner radius R0, length L1 and thickness d; the metal diaphragms are symmetrically welded to the inner wall of the third circular waveguide, and are respectively referred to as first diaphragm and second diaphragm, which have the same shape, in the form of solid ship, and the center of the first diaphragm is equidistant from the input port and the output port. The first diaphragm is composed of first left diaphragm slope, first diaphragm middle section and first right diaphragm slope, wherein the first left diaphragm slope and the first right diaphragm slope have the same shape, in the form of oblique cutting cylinder (i.e. the part of the solid cylinder after being divided by a plane intersecting the end face and the side face of the cylinder, only having three faces). The axial length of the first left diaphragm slope is L2, the first diaphragm middle section is in the form of cylindrical horizontal cross section (i.e. the part of the solid cylinder after being divided by a plane intersecting the two end faces and being parallel to the axis, with the two end arcs being inferior arcs), with axial length L3 and thickness h. The joint between the first left diaphragm slope and the first diaphragm middle section is chamfered, with chamfer radius r. The joint between the first right diaphragm slope and the first diaphragm middle section is chamfered.

[0016] For the convenience of description, the conditions met by the structural parameters of the above design are introduced as follows:

[0017] 1. The inner radius R0 of the first circular waveguide needs to meet the condition that the high-order mode TM 01 mode can pass through in the first circular waveguide, i.e. R0≥2π / λ0 / 2.4048, λ0 is the wavelength of the input microwave in free space, and the thickness d is generally 3-5 mm.

[0018] 2. The parameters of the first curved circular waveguide, the second curved circular waveguide and the third curved circular waveguide need to meet the condition that the TM 01 mode of the circular waveguide is converted into TE 11 mode, for the convenience of processing, R1=R2=R3, 2θ1=θ2=2θ3, and wherein μ 01 is the first root of the first-order 0 Bessel function J0, v 11 is the first root of the first-order 1 Bessel derivative function J1’, k is the free space wave number, β1 is the phase constant of TM 01 mode, and β2 is the phase constant of TE11 Phase constant of the mode.

[0019] 3. The axial length L3 and thickness h of the middle section of the first film of the circular polarizer can be changed to change the TE 11 Mode cutoff wavelength, the cutoff wavelength of the vertical component of the first film under different conditions is calculated by electromagnetic simulation software CST c1 , the cutoff wavelength of the parallel component of the first film c2 , so that L3(k1-k2)=π / 4, wherein k1 is the phase shift constant perpendicular to the middle section 222 of the first film, and k2 is the phase shift constant parallel to the middle section 222 of the first film, The value of L3 is obtained from L3=π / 4 / (k1-k2).

[0020] Under the condition of R0≥2π / λ0 / 2.4048, first, according to R1=R2=R3, 2θ1=θ2=2θ3, The values of R1, R2, R3, θ1, θ2, and θ3 are calculated, and then the microwave transmission efficiency to the output end of the three-bend mode converter is set to be greater than 99%, and the accurate values of the parameters R1, R2, R3, θ1, θ2, and θ3 of the three-bend mode converter can be obtained; second, the cutoff wavelength of the vertical component of the first film under different conditions is calculated by electromagnetic simulation software CST c1 , the cutoff wavelength of the parallel component of the first film c2 , so that L3=π / 4 / (k1-k2), and the initial value of L3 is obtained, and then the microwave transmission efficiency from the first circular waveguide of the film-loaded circular polarizer to the second circular waveguide is set to be greater than 99%, and in addition, the amplitudes of the two polarization components of the TE 11 mode under the circular polarization output mode are equal, and the phase difference is 90°, and after optimization, the accurate values of the film parameters L2, L3, and h can be obtained.

[0021] The working process of the application is as follows: the application can realize the conversion of the TM 01 mode to the TE 11 mode, and can realize the switching of the left-handed circular polarization, right-handed circular polarization, and linear polarization of the TE 11 mode. In order to clearly introduce the working process of the polarization conversion, the working processes of the three-bend TM 01 -TE 11 mode converter and the film-loaded circular polarizer are introduced respectively, which are as follows: the first circular waveguide 11 receives the TM 01 mode microwave from the microwave source, and converts the TM 01The mode is input into the first curved circular waveguide 12, the first curved circular waveguide 12, the second curved circular waveguide 13 and the third curved circular waveguide 14 convert the TM 01 mode microwave into TE 11 mode microwave. 11 mode microwave is output from the second circular waveguide 15, and the TM 01 -TE 11 mode microwave is converted.

[0022] The second circular waveguide 15 receives linearly polarized TE 11 mode microwave from the third curved circular waveguide 14, and the linearly polarized TE 11 mode microwave is propagated to the membrane-loaded linear-circular polarizer, and the linearly polarized TE 11 mode is decomposed into parallel polarized waves, and the linearly polarized TE 11 mode is decomposed into vertical polarized waves. Since the first metal membrane and the second metal membrane have a greater influence on the phase shift constant of the vertical polarized waves than on the phase shift constant of the parallel polarized waves, the first metal membrane and the second metal membrane generate a certain phase difference for the two polarized microwaves.

[0023] The first metal membrane and the second metal membrane are transitioned by a membrane slope, which can control the reflection of the vertical polarized electric field components of the first metal membrane and the second metal membrane at a low level. The middle section of the membrane and the connection between the membrane slope of the first metal membrane and the second metal membrane are chamfered, which can effectively reduce the electric field strength at these positions and prevent breakdown phenomenon from occurring, effectively improving the power capacity of the polarizer. The circular waveguide linearly polarized TE 11 mode is converted into circular waveguide circularly polarized TE 11 mode after passing through the first metal membrane and the second metal membrane, and is output from the third circular waveguide 21.

[0024] The microwave is input into the first circular waveguide 11 of the TM 01 -TE 01 mode converter in the form of a three-bend TM 11 -TE 11 mode from the third circular waveguide 21 of the circular polarizer, and the three-bend TM 01 -TE 11 mode converter is fixed, and the membrane-loaded circular polarizer is rotated around its own axis, and the angle between the membrane-loaded circular polarizer and the three-bend TM 01 -TE 11 mode converter is changed (i.e. the angle θ between the symmetry planes BB' and AA' is-45°, 0° and +45°, respectively), and left-handed TE 11 circularly polarized mode, TE11 Linear polarization mode, right-handed TE 11 Circular polarization mode, i.e. changeable polarization.

[0025] Compared with the prior art, the present application has the following technical effects:

[0026] 1. The three-bend TM 01 -TE 11 Mode converter has high mode conversion efficiency, and the mode conversion efficiency of the TM 01 -TE 11 exceeds 99.5%, which affects the transmission efficiency of the entire polarizer, and the transmission efficiency of the polarizer at the center frequency exceeds 99.5%.

[0027] 2. The present application has simple structure, easy to realize the function of changing polarization (the output polarization mode can be changed by rotating the diaphragm loaded circular polarizer), and can realize linear, left-handed and right-handed circular polarization three ways output. Since the structure is all-metal structure (usually aluminum), and does not involve dielectric, it can realize GW-level power capacity. BRIEF DESCRIPTION OF DRAWINGS

[0028] Figure 1 is a schematic diagram of the overall structure of the present application.

[0029] Figure 2 is a schematic diagram of the three-bend TM 01 -TE 11 Mode converter structure 1.

[0030] Figure 3 is Figure 2 a sectional view along the AA' plane.

[0031] Figure 4 is a schematic diagram of the diaphragm loaded circular polarizer 2 of the present application.

[0032] Figure 5 is Figure 4 a sectional view along the BB' plane.

[0033] Figure 6 is a sectional view of the first diaphragm 22 and the second diaphragm 23.

[0034] Figure 7 is a schematic diagram of the first left diaphragm slope 221 in the form of a beveled cylinder.

[0035] Figure 8 is a schematic diagram of the first diaphragm middle section 222 in the form of a horizontal cross-section of a cylinder.

[0036] Figure 9 is a schematic diagram of the present application.

[0037] Figure 10 It is a left-handed schematic diagram of the present invention.

[0038] Figure 11 Schematic diagram of linear polarization of the present invention.

[0039] Figure 12 It is a right-handed schematic diagram of the present invention. DETAILED DESCRIPTION

[0040] The following embodiments are further described in conjunction with the accompanying drawings and examples. The following examples are only used to illustrate the present invention, but are not intended to limit the scope of the present invention.

[0041] Figure 1 It is a schematic diagram of the overall structure of the present invention; Figure 1 As shown, the present invention consists of three bends TM 01 -TE 11 Mode converter 1 and diaphragm loaded circular polarizer 2, three-bend TM 01 -TE 11 The mode converter 1 and the patch-loaded circular polarizer 2 are coaxially connected, and the patch-loaded circular polarizer 2 can rotate around the central axis OO' of the patch-loaded circular polarizer 2. 01 -TE 11 Mode converter 1 converts microwaves from TM01 mode to linearly polarized TE 11 Mode, the diaphragm-loaded circular polarizer 2 converts the microwave from linear polarization to TE 11 Mode conversion to circularly polarized TE 11 model.

[0042] Figure 2 It is a three-bend TM 01 -TE 11 3D view of mode converter 1, Figure 3 yes Figure 2 Cross-sectional view along AA' plane; Figure 2 As shown, Triple Bend™ 01 -TE 11The mode converter 1 is made of metal (preferably aluminum) and consists of a first circular waveguide 11, a first curved circular waveguide 12, a second curved circular waveguide 13, a third curved circular waveguide 14, and a second circular waveguide 15. The first circular waveguide 11 and the second circular waveguide 15 are coaxial. One end of the first circular waveguide 11 is connected to the output port of the microwave source as the input port of the present invention, and the other end is connected to the first curved circular waveguide 12; one end of the first curved circular waveguide 12 is connected to the first circular waveguide 11, and the other end is connected to the second curved circular waveguide 13; one end of the second curved circular waveguide 13 is connected to the first curved circular waveguide 12, and the other end is connected to the third curved circular waveguide 14; one end of the third curved circular waveguide 14 is connected to the second curved circular waveguide 13, and the other end is connected to the second circular waveguide 15; one end of the second circular waveguide 15 is connected to the third curved circular waveguide 14, and the other end serves as a three-bend TM 01 -TE 11 The output port of the mode converter 1 is connected to the input end of the diaphragm-loaded circular polarizer 2. The end of the invention close to the microwave source is defined as the input end, and the end away from the microwave source is defined as the output end. Figure 3 As shown, the first circular waveguide 11 has an inner radius of R0, a length of h0, and a thickness of d; the first curved circular waveguide 12 has an inner radius of R0, a curvature radius of R1, a bending angle of θ1, and a thickness of d; the second curved circular waveguide 13 has an inner radius of R0, a curvature radius of R2, a bending angle of θ2, and a thickness of d; the third curved circular waveguide 14 has an inner radius of R0, a curvature radius of R3, a bending angle of θ3, and a thickness of d; the second circular waveguide 15 has an inner radius of R0, a length of h0, and a thickness of d. The first circular waveguide 11 receives TM from a microwave source. 01 mode microwave, the TM 01 The first curved circular waveguide 12, the second curved circular waveguide 13, and the third curved circular waveguide 14 transmit the microwave of the mode to the first curved circular waveguide 12; the ... 01 Mode microwave conversion to TE 11 mode microwave, and TE 11 The mode microwave is coaxially output to the second circular waveguide 15, which transmits the TE 11 The mode microwave is output to the diaphragm-loaded circular polarizer 2.

[0043] Figure 4 This is a three-dimensional view of the diaphragm-loaded circular polarizer 2. Figure 5 yes Figure 4 BB' plane cross-sectional view, Figure 6 for Figure 4 A cross-sectional view of the first diaphragm 22 and the second diaphragm 23; Figure 4 As shown, the diaphragm-loaded circular polarizer 2 is composed of a third circular waveguide 21, a first diaphragm 22, and a second diaphragm 23.Figure 5 As shown, the third circular waveguide 21 is made of metal material (preferably aluminum), the inner radius is equal to R0, the length is L1, and the thickness is equal to d; the first diaphragm 22 and the second diaphragm 23 are symmetrically welded on the inner wall of the third circular waveguide 21 along the axis OO' of the third circular waveguide 21, and the center position of the first diaphragm 22 is equal to the distance between the input port and the output port. The shapes of the first diaphragm 22 and the second diaphragm 23 are exactly the same, and are solid boat-shaped. As shown in the figure, Figure 6 As shown, the first diaphragm 22 is composed of a first left diaphragm slope 221, a first diaphragm middle section 222, and a first right diaphragm slope 223. The shapes of the first left diaphragm slope 221 and the first right diaphragm slope 223 are exactly the same, and the first left diaphragm slope 221 is in the shape of a beveled cylinder (i.e. the part left after a solid cylinder is divided by a plane intersecting the end face and the side face of the cylinder, which has only three faces, i.e. Figure 7 the middle blue part), and the axial length is L2; the first diaphragm middle section 222 is in the shape of a horizontal cross-section of a cylinder (i.e. the part left after a solid cylinder is divided by a plane intersecting the two end faces and parallel to the axis, and the two end arcs are inferior arcs, i.e. Figure 8 the middle blue part), and the axial length is L3, and the thickness of the first diaphragm middle section 222 is h (see Figure 5 ). The connecting position between the first right diaphragm slope 223 and the first diaphragm middle section 222 is chamfered, and the chamfer radius is r. The second diaphragm 23 is composed of a second left diaphragm slope 231, a second diaphragm middle section 232, and a second right diaphragm slope 233, wherein the shapes of the second left diaphragm slope 231 and the second right diaphragm slope 233 are exactly the same. The axial length of the second left diaphragm slope 231 is equal to L2, the axial length of the second diaphragm middle section 232 is equal to L3, and the thickness of the second diaphragm middle section 232 is equal to h (see Figure 5 ). The connecting position between the second right diaphragm slope 233 and the diaphragm middle section 232 is chamfered, and the chamfer radius is equal to r. The third circular waveguide 21 is the output waveguide of the diaphragm-loaded circular polarizer 2, and the first diaphragm 22 and the second diaphragm 23 realize circular polarization by changing the propagation constant of electromagnetic waves in the direction perpendicular to the diaphragm. The third circular waveguide 21 is a three-bend TM 01 -TE 11 mode converter 1 is connected through a rotating joint.

[0044] Figure 9 is the rotating schematic diagram of the present application, the symmetry plane of the three-bend mode converter 1 is AA', the symmetry plane of the diaphragm-loaded circular polarizer 2 is BB', the diaphragm-loaded circular polarizer 2 is coaxially rotated with the three-bend mode converter 1, and the included angle θ is the included angle between the two symmetry planes AA' and BB';

[0045] Figure 10 is the left-handed circular polarization mode schematic diagram of the present application; Figure 11 is the linear polarization mode schematic diagram of the present application;Figure 12 is a schematic diagram of the right-handed circular polarization mode of the present application; when the included angle θ (i.e. the included angle of the symmetry plane BB' and the AA' plane) between the diaphragm-loaded circular polarizer 2 and the three-bend mode converter 1 is -45°, the output is left-handed circular polarization mode microwave (such as Figure 10 ); when the included angle θ between the diaphragm-loaded circular polarizer 2 and the three-bend mode converter 1 is 0°, the output is left-handed circular polarization mode microwave (such as Figure 11 ); when the included angle θ between the diaphragm-loaded circular polarizer 2 and the three-bend mode converter 1 is 45°, the output is left-handed circular polarization mode microwave (such as Figure 12 ).

[0046] To verify the effect of the present application, the following is the embodiment 1 of the present application:

[0047] For the L-band frequency f = 1.62 GHz microwave source, the main dimensions of embodiment 1 are as follows: the inner radius of the first circular waveguide 11 is R0 = 105 mm, the length is h0 = 200 mm, and the thickness is d = 5 mm; the inner radius of the first curved circular waveguide 12 is R0 = 105 mm, the curvature radius is R1 = 904.3 mm, and the bending angle is θ1 = 25.4°; the inner radius of the second curved circular waveguide 13 is R0 = 105 mm, the curvature radius is R2 = 1019.9 mm, and the bending angle is θ2 = 50.8°; the inner radius of the third curved circular waveguide 14 is R0 = 105 mm, the curvature radius is R3 = 904.3 mm, and the bending angle is θ3 = 25.4°; the inner radius of the second circular waveguide 15 is R0 = 105 mm, and the length is h0 = 200 mm. The third circular waveguide 21 is made of metal material, the inner radius is R0 = 105 mm, the length is L1 = 680 mm; the axial length of the left diaphragm slope 221 and the right diaphragm 223 is L2 = 122.3 mm, the axial length of the first diaphragm middle section 222 and the second diaphragm middle section 232 is L3 = 192.4 mm, and the thickness is h = 34.9 mm. The chamfer radius r = 32.3 mm at the connection position of the left diaphragm slope 221 and the diaphragm middle section 222 of the first diaphragm 22.

[0048] Adjust the included angle (i.e. the included angle of the symmetry plane BB' and the AA' plane) between the diaphragm-loaded circular polarizer 2 and the three-bend TM 01 -TE 11 mode converter 1 to -45°, it can be observed in the electromagnetic simulation software CST (2022) that the output is left-handed TE 11 circular polarization mode, the axial ratio is less than 1.02 within the working frequency band, and the conversion rate reaches more than 99.5%.

[0049] Adjust the included angle (i.e. the included angle of the symmetry plane BB' and the AA' plane) between the diaphragm-loaded circular polarizer 2 and the three-bend TM 01 -TE 11When the included angle of the mode converter 1 (i.e. the included angle of the symmetry plane BB' and the AA' plane) is 0°, it can be observed in the electromagnetic simulation software CST that the output is TE 11 linearly polarized mode, and the conversion rate is above 99.5% in the working frequency band.

[0050] Adjustable diaphragm-loaded circular polarizer 2 and three-bend TM 01 -TE 11 When the included angle of the mode converter 1 (i.e. the included angle of the symmetry plane BB' and the AA' plane) is +45°, it can be observed in the electromagnetic simulation software CST that the output is right-handed TE 11 circularly polarized mode, and the conversion rate is above 99.5% in the working frequency band, with an axial ratio below 1.02.

[0051] Under vacuum conditions, the system power capacity is more than 20 GW through electromagnetic simulation software CST.

[0052] Example 2:

[0053] For a microwave source with an S-band frequency f = 3.24 GHz, the main dimensions of example 2 are as follows: the first circular waveguide 11 has an inner radius R0 = 52.5 mm, a length h0 = 100 mm, and a thickness d = 5 mm; the first curved circular waveguide 12 has an inner radius R0 = 52.5 mm, a curvature radius R1 = 452.1 mm, and a bending angle θ1 = 25.4°; the second curved circular waveguide 13 has an inner radius R0 = 52.5 mm, a curvature radius R2 = 509.9 mm, and a bending angle θ2 = 50.8°; the third curved circular waveguide 14 has an inner radius R0 = 52.5 mm, a curvature radius R3 = 452.1 mm, and a bending angle θ3 = 25.4°; the second circular waveguide 15 has an inner radius R0 = 52.5 mm and a length h0 = 100 mm. The third circular waveguide 21 is made of a metal material, has an inner radius R0 = 52.5 mm, and a length L1 = 340 mm; the left diaphragm slope 221 and the right diaphragm 223 have an axial length L2 = 61.2 mm, the first diaphragm middle section 222 and the second diaphragm middle section 232 have an axial length L3 = 96.2 mm and a thickness h = 17.5 mm. The left diaphragm slope 221 of the first diaphragm 22 is connected to the diaphragm middle section 222 at a chamfered radius r = 16.2 mm.

[0054] Adjustable diaphragm-loaded circular polarizer 2 and three-bend TM 01 -TE 11 When the included angle of the mode converter 1 (i.e. the included angle of the symmetry plane BB' and the AA' plane) is -45°, it can be observed in the electromagnetic simulation software CST (2022) that the output is left-handed TE 11Circular polarization mode, the axial ratio is less than 1.05 in the working frequency band, and the conversion rate is more than 99.5%.

[0055] Adjustable diaphragm loaded circular polarizer 2 with three bends TM 01 -TE 11 When the included angle of the mode converter 1 (i.e. the included angle of the symmetry plane BB' and the plane AA') is 0°, it can be observed in the simulation in the electromagnetic simulation software CST that the output is TE 11 Linear polarization mode, the conversion rate is more than 99.5% in the working frequency band.

[0056] Adjustable diaphragm loaded circular polarizer 2 with three bends TM 01 -TE 11 When the included angle of the mode converter 1 (i.e. the included angle of the symmetry plane BB' and the plane AA') is +45°, it can be observed in the simulation in the electromagnetic simulation software CST that the output is right-handed TE 11 Circular polarization mode, the axial ratio is less than 1.05 in the working frequency band, and the conversion rate is more than 99.5%.

[0057] Under vacuum conditions, the system power capacity is more than 10 GW, which can be obtained by simulation in the electromagnetic simulation software CST.

[0058] Embodiment 3:

[0059] For a microwave source with a C-band frequency f = 6.48 GHz, the main dimensions of embodiment 3 are as follows: the first circular waveguide 11 has an inner radius R0 = 26.3 mm, a length h0 = 50 mm, and a thickness d = 4 mm; the first curved circular waveguide 12 has an inner radius R0 = 26.3 mm, a curvature radius R1 = 266 mm, and a bending angle θ1 = 25.4°; the second curved circular waveguide 13 has an inner radius R0 = 26.3 mm, a curvature radius R2 = 254.9 mm, and a bending angle θ2 = 50.8°; the third curved circular waveguide 14 has an inner radius R0 = 26.3 mm, a curvature radius R3 = 266 mm, and a bending angle θ3 = 25.4°; the second circular waveguide 15 has an inner radius R0 = 26.3 mm and a length h0 = 50 mm. The third circular waveguide 21 is made of a metal material, has an inner radius R0 = 26.3 mm and a length L1 = 170 mm; the left diaphragm slope 221 and the right diaphragm 223 have an axial length L2 = 30.6 mm, the first diaphragm middle section 222 and the second diaphragm middle section 232 have an axial length L3 = 48.1 mm and a thickness h = 8.8 mm. The left diaphragm slope 221 of the first diaphragm 22 is connected to the diaphragm middle section 222 at a chamfered position with a radius r = 8.1 mm.

[0060] Adjustable diaphragm loaded circular polarizer 2 with three bends TM 01 -TE 11When the included angle of the mode converter 1 (i.e. the included angle of the symmetry plane BB' and the AA' plane) is -45°, it can be observed from the simulation in the electromagnetic simulation software CST (2022) that the output is left-handed TE 11 Circular polarization mode, the axial ratio is less than 1.04 within the working frequency band, and the conversion rate is more than 99.5%.

[0061] Adjusting diaphragm loaded circular polarizer 2 and three-bend TM 01 -TE 11 When the included angle of the mode converter 1 (i.e. the included angle of the symmetry plane BB' and the AA' plane) is 0°, it can be observed from the simulation in the electromagnetic simulation software CST that the output is TE 11 Linear polarization mode, the conversion rate is more than 99.5% within the working frequency band.

[0062] Adjusting diaphragm loaded circular polarizer 2 and three-bend TM 01 -TE 11 When the included angle of the mode converter 1 (i.e. the included angle of the symmetry plane BB' and the AA' plane) is +45°, it can be observed from the simulation in the electromagnetic simulation software CST that the output is right-handed TE 11 Circular polarization mode, the axial ratio is less than 1.04 within the working frequency band, and the conversion rate is more than 99.5%.

[0063] Under vacuum conditions, it can be obtained from the simulation in the electromagnetic simulation software CST that the system power capacity is more than 5GW.

[0064] From the above results, it can be seen that the embodiment of the present application adopts a full-metal structure, the structure meets the scaling principle, and has the characteristics of high transmission efficiency and large power capacity. The above embodiments are only used to illustrate the present application, and are not intended to limit the present application. Those skilled in the related art can make various changes and modifications without departing from the spirit and scope of the present application, and therefore all equivalent technical solutions also belong to the protection scope of the present application.

Claims

1. A three-bend diaphragm loaded polarizer, characterized in that The three-bend diaphragm loaded polarizer is composed of three-bend TM 01 -TE 11 The mode converter (1) and the diaphragm-loaded circular polarizer (2) are composed of three-bend TM 01 -TE 11 The mode converter (1) and the diaphragm-loaded circular polarizer (2) are coaxially connected, and the diaphragm-loaded circular polarizer (2) can rotate around the central axis OO' of the diaphragm-loaded circular polarizer (2); three-bend TM 01 -TE 11 The mode converter (1) converts microwaves from TM 01 Mode conversion to linearly polarized TE 11 mode, the diaphragm-loaded circular polarizer (2) converts microwaves from linearly polarized TE 11 Mode conversion to circularly polarized TE 11 model; Triple Bend™ 01 -TE 11 The mode converter (1) is made of metal material and consists of a first circular waveguide (11), a first curved circular waveguide (12), a second curved circular waveguide (13), a third curved circular waveguide (14) and a second circular waveguide (15). The first circular waveguide (11) and the second circular waveguide (15) are coaxial. One end of the first circular waveguide (11) is connected to the output port of the microwave source as the input port of the three-bend diaphragm loaded polarizer, and the other end is connected to the first curved circular waveguide (12). The first curved circular waveguide (12) is connected to the first circular waveguide (11) at one end and to the second curved circular waveguide (13) at the other end; the second curved circular waveguide (13) is connected to the first curved circular waveguide (12) at one end and to the third curved circular waveguide (14) at the other end; the third curved circular waveguide (14) is connected to the second curved circular waveguide (13) at one end and to the second circular waveguide (15) at the other end; the second circular waveguide (15) is connected to the third curved circular waveguide (14) at one end and to the third curved circular waveguide (14) at the other end as a three-bend TM 01 -TE 11 The output port of the mode converter (1) is connected to the input end of the diaphragm-loaded circular polarizer (2); the end close to the microwave source is defined as the input end of the three-bend diaphragm-loaded variable polarizer, and the end away from the microwave source is defined as the output end of the three-bend diaphragm-loaded variable polarizer; the first circular waveguide (11) has an inner radius of R0, a length of h0, and a side wall thickness of d; the first curved circular waveguide (12) has an inner radius equal to R0, a curvature radius of R1, a bending angle of θ1, and a side wall thickness equal to d; the second curved circular waveguide (13) has an inner radius equal to R0, a curvature radius of R2, a bending angle of θ2, and a side wall thickness equal to d; the third curved circular waveguide (14) has an inner radius equal to R0, a curvature radius of R3, a bending angle of θ3, and a side wall thickness equal to d; the second circular waveguide (15) has an inner radius equal to R0, a length equal to h0, and a side wall thickness equal to d; the first circular waveguide (11) receives TM from the microwave source 01 mode microwave, the TM 01 The microwave of the mode is transmitted to the first curved circular waveguide (12); the first curved circular waveguide (12), the second curved circular waveguide (13), and the third curved circular waveguide (14) are connected to the TM by the curved waveguide mode coupling theory. 01 Mode microwave conversion to TE 11 mode microwave, and TE 11 The mode microwave is coaxially output to the second circular waveguide (15), and the second circular waveguide (15) transmits the TE 11 The mode microwave is output to a diaphragm-loaded circular polarizer (2); The diaphragm-loaded circular polarizer (2) is composed of a third circular waveguide (21), a first diaphragm (22) and a second diaphragm (23); the third circular waveguide (21) is made of a metal material, and its inner radius is equal to R0, its length is L1, and its thickness is equal to d; the first diaphragm (22) and the second diaphragm (23) are symmetrically welded to the inner wall of the third circular waveguide (21) along the axis OO' of the third circular waveguide (21), and the center position of the first diaphragm (22) is equidistant from the input port and the output port; the first diaphragm (22) and the second diaphragm (23) have the same shape. , in the shape of a solid boat; the first diaphragm (22) is composed of a first left diaphragm slope (221), a first diaphragm middle section (222), and a first right diaphragm slope (223); the first left diaphragm slope (221) and the first right diaphragm slope (223) are of the same shape, the first left diaphragm slope (221) is in the shape of an oblique cylinder, that is, a portion of only three surfaces left after a solid cylinder is divided by a plane intersecting the end face and the side face of the cylinder, and the axial length is L2; ​​the first diaphragm middle section (222) is in the shape of a horizontal cross section of a cylinder, that is, a plane intersecting the end face and the side face of the cylinder The solid cylinder is divided by a plane intersecting the plane and parallel to the axis, and the arcs at both ends are the inferior arc parts, with an axial length of L3 and a thickness of h; the first right diaphragm slope (223) is chamfered at the connection position with the first diaphragm middle section (222), and the chamfer radius is r; the second diaphragm (23) is composed of a second left diaphragm slope (231), a second diaphragm middle section (232), and a second right diaphragm slope (233), and the second left diaphragm slope (231) and the second right diaphragm slope (233) have the same shape; the second left diaphragm slope (231) The axial length of the second diaphragm middle section (232) is equal to L2, the axial length of the second diaphragm middle section (232) is equal to L3, and the thickness of the second diaphragm middle section (232) is equal to h; the second right diaphragm slope (233) is chamfered at the position where it is connected to the second diaphragm middle section (232), and the chamfer radius is equal to r; the third circular waveguide (21) is the output waveguide of the diaphragm-loaded circular polarizer (2), and the first diaphragm (22) and the second diaphragm (23) achieve circular polarization by changing the propagation constant of the electromagnetic wave in the direction perpendicular to the diaphragm; the third circular waveguide (21) and the three-bend TM 01 -TE 11 The mode converter (1) is connected via a revolute joint.

2. The three-bend diaphragm loaded polarizer according to claim 1, characterized in that The Triple Bend™ 01 -TE 11 The mode converter (1) is made of aluminum, and the third circular waveguide (21) is made of aluminum.

3. The three-bend diaphragm loaded polarizer according to claim 1, characterized in that The inner radius R0 of the first circular waveguide (11) satisfies R0≥2π / λ0 / 2.4048, λ0 is the wavelength of the input microwave in free space, and the side wall thickness d of the first circular waveguide (11) is 3-5 mm.

4. The three-bend diaphragm loaded polarizer according to claim 3, characterized in that The parameters of the first curved circular waveguide (12), the second curved circular waveguide (13), and the third curved circular waveguide (14) need to satisfy the requirement of the circular waveguide TM 01 Mode conversion to TE 11 The conditions of the mode require R1=R2=R3, 2θ1=θ2=2θ3, and Where μ 01 is the first root of the first-order Bessel function J0, ν 11 is the first root of the first-order Bessel derivative function J1'; k is the free space wave number; β1 is TM 01 The phase constant of the mode, β2 is the TE 11 The phase constant of the mode.

5. The three-bend diaphragm loaded polarizer according to claim 4, characterized in that The axial length L3 of the first diaphragm middle section (222) of the circular polarizer satisfies L3=π / 4 / (k1-k2), k1 is a phase shift constant perpendicular to the first diaphragm middle section (222), k2 is a phase shift constant parallel to the first diaphragm middle section (222), λ c1 is the cutoff wavelength of the vertical component of the first diaphragm, λ c2 is the cutoff wavelength of the parallel component of the first diaphragm, λ c1 and λ c2 Calculated using electromagnetic simulation software CST.

6. The three-bend diaphragm loaded polarizer according to claim 5, characterized in that The method for determining the precise values ​​of L2, L3, and h is as follows: using electromagnetic simulation software CST, under the condition that R0≥2π / λ0 / 2.4048 is satisfied, first according to R1=R2=R3, 2θ1=θ2=2θ3, The values ​​of R1, R2, R3, θ1, θ2, and θ3 were calculated, and then the efficiency of microwave transmission to the output end of the three-bend mode converter was set to be greater than 99%. The precise values ​​of the three-bend mode converter parameters R1, R2, R3, θ1, θ2, and θ3 were optimized. Secondly, the electromagnetic simulation software CST was used to calculate the cutoff wavelength λ of the vertical component of the first diaphragm under different conditions. c1 , the cutoff wavelength λ of the parallel component of the first diaphragm c2 , so that L3 = π / 4 / (k1-k2), get the rough value of L3, then set the microwave from the diaphragm loaded circular polarizer first circular waveguide input, from the second circular waveguide output and the transmission efficiency is greater than 99%, in addition, in the circular polarization output mode TE 11 The amplitudes of the two polarization components of the mode are equal and the phase difference is 90°. After optimization, the precise values ​​of the membrane parameters L2, L3, and h are obtained.

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