A compact high power waveguide radial power divider / combiner

Abstract

The present invention discloses a compact high-power waveguide radial power distributor / synthesizer, the purpose of which is to solve the problems of narrow bandwidth, large lateral size, low power capacity, etc. of the existing power distributor / synthesizer. The present invention is composed of three parts, namely, a conical circular waveguide-coaxial waveguide transition structure, a coaxial waveguide-circumferential rectangular waveguide array transition structure, and a circular curved waveguide array, which are sequentially coaxially connected and arranged in a central rotational symmetric manner along the central axis. The conical circular waveguide-coaxial waveguide transition structure is composed of a circular waveguide, a conical circular waveguide-coaxial transition waveguide, and a coaxial waveguide; the coaxial waveguide-circumferential rectangular waveguide array transition structure is composed of N fan-shaped-rectangular waveguide transition sections arranged circumferentially around the central axis; the upper end of the coaxial waveguide-circumferential rectangular waveguide array transition structure is a section surrounded by N fans, and the lower end is a section surrounded by N rectangles. The circular curved waveguide array is composed of N curved waveguides. The present invention has a wide working frequency band, a small lateral size, and a power capacity of the order of GW.

Description

Technical Field

[0001] The present invention relates to the technical field of high-power microwave channel power synthesis, and in particular provides a compact high-power circular waveguide radial power distributor / synthesizer (" / " indicates both distribution and synthesis functions). Background Art

[0002] High-Power-Microwave (HPM) channel power synthesis technology utilizes phase control and electromagnetic field coupling to coherently synthesize microwave signals generated by multiple independent HPM system units inside a waveguide power synthesizer. It is one of the key technical approaches to achieve microwave power output at the gigawatt (GW) level. Therefore, it is of great significance to study waveguide power distributors / synthesizers with wide operating frequency band, high power capacity and synthesis efficiency. At present, waveguide power distributors / synthesizers in the HPM field are mainly divided into two categories: one is a multi-stage cascade power distributor / synthesizer based on a rectangular waveguide T-type structure. The second is a power distributor / synthesizer that combines the angularly symmetrical mode of a circular waveguide or coaxial waveguide with the waveguide sidewall coupling technology. For the first type of power distributor / synthesizer, in order to ensure that it has good transmission characteristics, the input waveguide usually adopts the main mode (TE 10 For the second type of power divider / combiner, according to the difference in working principle and implementation mechanism, they are further divided into circular waveguide based TM 01 mode, coaxial TEM mode, and circular waveguide TE 01 Mode power divider / combiner. Among them, the circular waveguide TM 01 The electric field distribution of the circular waveguide TE mode and the coaxial TEM mode is relatively concentrated. For the former, the electric field is mainly focused on the central area of ​​the circular waveguide, while for the latter, the electric field is mainly concentrated around the inner conductor of the coaxial line. The radial sidewall coupling of the waveguide has a large disturbance on these two electric fields, which is easy to produce a large electric field enhancement effect, thereby limiting the power capacity and working bandwidth of the power divider / combiner. In contrast, the circular waveguide TE 01 The electric field of the mode is mainly concentrated in the annular region inside the waveguide and is relatively low at the edge and center. 01 The mode has the characteristics of low heat loss at high frequencies, which makes the circular waveguide based TE 01 The power / distribution synthesizer of this mode has become a highly anticipated technical solution in the field of HPM channel power synthesis.

[0003] At present, José R. Montejo-Garai et al. from the Center for Information Processing and Telecommunications of the Political Institute of Madrid, Spain, have proposed a method based on low over-mode (TE 02 Mode cutoff) circular waveguide TE 01High-performance 16-way Ku-band radial power combiner based on the TE 01 -circular waveguide mode[J].Review of Scientific Instruments,2018,89(3):034703), based on coaxial waveguide TE 01 Due to the rotational symmetry of the mode, 16 rectangular waveguides of the same size are evenly arranged along the radial direction of the coaxial waveguide to achieve n (n = 16) waveguide space radial power distribution / synthesis. In order to improve the transmission efficiency, they designed a secondary cylindrical ladder impedance matching structure at the bottom of the circular waveguide, which made the transmission efficiency reach 96.4%. However, the cylindrical ladder impedance matching structure is a mutation structure, which will affect the bandwidth and power capacity of the power divider / synthesizer, so that its bandwidth can only reach 16.7%, and its power capacity can only reach 131MW under vacuum conditions.

[0004] A method based on low over-modulus (TE) was proposed by Chu Qingxin et al. from South China University of Technology. 02 Mode cutoff) circular waveguide TE 01 An Isolated Radial Power Divider via Circular Waveguide TE 01 Mode Transducer [J]. IEEE Transactions on Microwave Theory and Techniques, 2015, 63 (12): 3988-3996). They improved the return loss of the power divider / combiner by introducing a resistive baffle at the sidewall coupling port of the rectangular waveguide, and enhanced the isolation effect between the output ports, achieving 20 (n = 20) radial power division / combination (working bandwidth reached 25%). At the same time, in order to improve the transmission efficiency, the design also connects the sidewall coupling port to a rectangular transition waveguide to achieve a smooth transition to the standard rectangular waveguide output, so that the transmission efficiency reaches 86.1%. However, due to the breakdown electric field limitation of the resistive baffle material, the power capacity of the divider / combiner is difficult to reach the MW level. In addition, the longer rectangular transition waveguide also increases the lateral size of the entire divider / combiner (the lateral size exceeds 4.1λ). mid ,λ midis the wavelength corresponding to the center frequency), which affects its structural compactness.

[0005] In order to effectively suppress the high-order modes that may be excited during the coupling process of the rectangular waveguide sidewall, the input ends of the above two power dividers / combiners adopt low overmode circular waveguides (TE 02 Mode cutoff), which means that within the operating frequency range, the total number of transmission modes supported by the circular waveguide (including all degenerate modes) usually does not exceed 24. Correspondingly, the size of the circular waveguide usually cannot exceed 1.1 times the operating wavelength. However, the size of the circular waveguide is positively correlated with its power capacity. Therefore, the size limitation of the circular waveguide at the input end is also the main reason that restricts these two power dividers / combiners from reaching GW-level power capacity. Summary of the invention

[0006] The technical problem to be solved by the present invention is to provide a compact high-power circular waveguide radial power distributor / synthesizer, which effectively solves the problems of narrow bandwidth, large lateral size, and difficulty in reaching GW level of power capacity of existing waveguide radial power distributor / synthesizer, and eliminates the limitation of the power capacity of traditional power distributor / synthesizer on the size of input circular waveguide.

[0007] The technical solution of the present invention is:

[0008] The compact high-power circular waveguide radial power distributor / synthesizer of the present invention is composed of three parts, which are sequentially coaxially connected, namely, a conical circular waveguide-coaxial waveguide transition structure, a coaxial waveguide-circumferential rectangular waveguide array transition structure and a circular curved waveguide array. These three parts are all made of metal materials. The entire power distributor / synthesizer is arranged in a central rotationally symmetrical layout along the central axis, which can ensure the consistency of the microwave amplitude and phase of each rectangular waveguide output port. The input port of the present invention is connected to the antenna transmission system at the rear end of the HPM channel power synthesis system, and the N output ports are respectively connected to a microwave source module. N is a positive integer, 1≤n≤N, and the value of N can be determined according to the number required for microwave power distribution / synthesis.

[0009] The conical circular waveguide-coaxial waveguide transition structure consists of a circular waveguide, a conical circular waveguide-coaxial transition waveguide and a coaxial waveguide. The circular waveguide is a cylinder with an inner radius of r0 and a wall thickness equal to the thickness h of the circular waveguide of the antenna transmission system at the rear end of the external HPM channel power synthesis system. The circular waveguide is used to transfer the synthesized TE 01 The mode microwave is transmitted to the antenna transmission system at the back end of the HPM channel power synthesis system. The coaxial waveguide consists of a first inner conductor coaxially nested in a first outer conductor. The first outer conductor is a cylinder with a length of l1 and a wall thickness equal to h. The first inner conductor is also a cylinder with a length equal to l1, an outer radius of r1, and a wall thickness equal to h. The difference between the inner radius of the first outer conductor and the outer radius of the first inner conductor is Δr. The annular channel between the first inner conductor and the first outer conductor is used to transmit the coaxial waveguide TE01 Mode microwave. The conical circular waveguide - coaxial transition waveguide is composed of a second outer conductor and a second inner conductor. The second outer conductor is in the shape of an inverted frustum of a cone (i.e., the radius of the upper port is greater than that of the lower port, satisfying r1 + Δr < r0). Its upper port is connected to the lower port of the circular waveguide, and the lower port is connected to the upper port of the first outer conductor of the coaxial waveguide. The second inner conductor is conical, and its lower port is connected to the upper port of the first inner conductor of the coaxial waveguide. The height of the second outer conductor is d1, the radius of the upper port is equal to r0, the radius of the lower port is equal to r1 + Δr, and the wall thickness is equal to h. The height of the second inner conductor is equal to d1, the radius of the lower port is equal to r1, and the wall thickness is equal to h.

[0010] The nested funnel - shaped channel between the second inner conductor and the second outer conductor of the conical circular waveguide - coaxial transition waveguide gradually converts the circular waveguide TE 01 mode microwave of the input circular waveguide into the TE 01 mode of the coaxial waveguide. According to the waveguide mode coupling theory, by reducing the perturbation of the electric field during the mode conversion process, the generation of higher - order modes can be effectively suppressed, thereby improving the mode conversion efficiency and broadening the working bandwidth. And for the circular waveguide TE 01 mode microwave, the electric field is concentrated in the annular region near the radius r0 / 2 from the center of the circular waveguide; for the coaxial waveguide TE 01 mode microwave, the electric field is concentrated in the annular region between the first inner conductor and the first outer conductor. Therefore, to reduce the electric field perturbation during the mode conversion between the circular waveguide TE 01 mode and the coaxial waveguide TE 01 mode, it is required that the electric field concentration regions of the TE 01 mode of the coaxial waveguide and the circular waveguide should match. That is

[0011] r1≈(r0 - Δr) / 2 (1)

[0012] If the coaxial waveguide operates in a low - over - mode state (i.e., the coaxial waveguide TE 01 mode is transmitted and the coaxial waveguide TE 02 mode is cutoff), the higher - order modes generated during the subsequent radial power distribution / synthesis process can be effectively suppressed, thereby achieving the broadening of the working bandwidth. Therefore, to ensure that the coaxial waveguide operates in a low - over - mode state, the dimensions of the coaxial waveguide (mainly referring to r1, Δr) must satisfy:

[0013]

[0014] where c0 is the propagation speed of light in free space, f min is the minimum frequency of the working frequency band set by the user (which is a design target and thus a known value), and f max is the maximum frequency of the working frequency band set by the user (which is a design target and thus a known value). TE for coaxial waveguide 01 Mode cut-off wavelength, TE for coaxial waveguide 02 The mode cutoff wavelength is related to the size of the coaxial waveguide and can be calculated using the eigenvalue equation of the coaxial waveguide:

[0015] J′ m (K c r1)N′ m (K c r2)-J′ m (K c r2))N′ m (K c r1)=0 (3)

[0016] in

[0017] r2=r1+Δr

[0018] In the formula, J′ m (K c r1) is the derivative of the first kind Bessel function, and m is the order of the first kind Bessel function. N′ m (K c r2) is the derivative of the second-kind Bessel function, m is the order of the second-kind Bessel function, r2 is the inner radius of the first outer conductor of the coaxial waveguide, K c is the eigenvalue, also known as the cutoff wave number. 01 and TE 02 mode, m = 0. It should be noted that formula (3) is a transcendental equation, which can generally be solved by numerical methods such as bisection or Newton's method. Formula (3) has countless roots K c , where the first root and Related, the second root and Related:

[0019]

[0020] Given the initial values ​​of r1 and Δr that satisfy r1≈(r0-Δr) / 2, r2=r1+Δr, we can find and like and Satisfying formula (2) indicates that r1 and Δr meet the requirements; if and If equation (2) is not satisfied, adjust r1 and Δr until the equation (3) and (4) are obtained. and Satisfying formula (2), the adjusted r1 and Δr are r1 and Δr that meet the design indicators.

[0021] The coaxial waveguide-circumferential rectangular waveguide array transition structure is composed of N fan-shaped-rectangular waveguide transition sections, namely the 1st fan-shaped-rectangular waveguide transition section, ..., the nth fan-shaped-rectangular waveguide transition section, ..., the Nth fan-shaped-rectangular waveguide transition section, which are arranged circumferentially around the central axis OO' of the present invention. The upper end of the coaxial waveguide-circumferential rectangular waveguide array transition structure is an annular section formed by N fans around a circle, which is connected to the lower end of the coaxial waveguide. The outer radius of the annular section is equal to the outer radius of the coaxial waveguide, the inner radius is equal to r1+Δr, and the wall thickness is equal to h. The lower end of the coaxial waveguide-circumferential rectangular waveguide array transition structure is a section formed by N rectangles of the same size around the central axis OO', which is connected to the upper end of the circular curved waveguide array. The N fan-shaped-rectangular waveguide transition sections are all formed by linear transition between the fan at the upper end and the rectangle at the lower end. The opening angles of the N fans are θ1, θ2, ..., θ n ,…,θ N The nth fan angle θ n The size of corresponds to the output power of the rectangular waveguide output port connected to it. If the output power of the N rectangular waveguide output ports of the present invention is p1, p2, ..., p n ,…,p N , the nth fan angle θ n for:

[0022]

[0023] θ1,θ2,…,θ n ,…,θ N They may not be equal, but the sizes of the rest of the N sector-rectangular waveguide transition sections are equal. Therefore, the nth sector-rectangular waveguide transition section is used as a representative to describe the characteristics of the rest of the sector-rectangular waveguide transition section. The height of the nth sector-rectangular waveguide transition section is d2, the length of the lower rectangle is a1, and the width is b1. In order to ensure that the nth sector-rectangular waveguide transition section has a higher microwave transmission efficiency, the lower rectangle should be located directly below the sector as much as possible. Satisfy:

[0024] Δa≈r1+(Δr-a1) / 2 (6)

[0025] Wherein, Δa is the distance between the lower end rectangle of the nth sector-rectangular waveguide transition section and the central axis OO'.

[0026] At the same time, a1 and b1 should also meet the main mode (TE 10 Mode) Transmission conditions:

[0027]

[0028] In the formula, max(a1,2b1) means taking the maximum value of a1 and 2b1.

[0029] The function of the coaxial waveguide-circumferential rectangular waveguide array transition structure is to convert the coaxial waveguide input TE 01 The mode microwave is converted into N rectangular waveguide TEs in the longitudinal direction 10 mode output. And make these N rectangular waveguides TE 10 The power of the mode microwaves is equal to the output power of the power divider / synthesizer p1, p2, ..., p n ,…,p N The height d2 of the fan-shaped-rectangular waveguide transition section has a significant impact on the conversion efficiency. Generally speaking, the larger d2 is, the higher the conversion efficiency is. However, in actual design, a trade-off needs to be made between the transmission efficiency and d2. Therefore, d2 is generally selected as the working wavelength range, that is,

[0030] The circular curved waveguide array is composed of N H-plane 90° curved waveguides of the same structure, namely, the 1st curved waveguide, ..., the nth curved waveguide, ..., the Nth curved waveguide, which are evenly arranged along the circumference. The upper ends of these N curved waveguides are connected to the lower ends of the N fan-shaped-rectangular waveguide transition sections of the coaxial waveguide-circumferential rectangular waveguide array transition structure, that is, the upper end of the nth curved waveguide is connected to the lower end of the nth fan-shaped-rectangular waveguide transition section. Therefore, the angle φ between the nth curved waveguide and the n+1th curved waveguide n satisfy:

[0031]

[0032] The main function of the circular bend waveguide array is to connect the N rectangular waveguides TE of the coaxial waveguide-circumferential rectangular waveguide array transition structure longitudinally through N H-plane 90° bend waveguides. 10 Mode microwave conversion to rectangular waveguide TE 10The mode is radially output, thereby realizing radial power distribution / synthesis of N waveguides. Because the structures of the N curved waveguides are the same, the nth curved waveguide is used as a representative to describe the characteristics of the curved waveguide. There is a section of rectangular waveguide at the upper end of the nth curved waveguide, which is connected to the rectangle at the lower end of the fan-shaped-rectangular waveguide transition section. The length of the rectangular waveguide at the upper end of the nth curved waveguide is l2, and the size of the rectangular waveguide is the same as the size of the rectangle at the lower end of the fan-shaped-rectangular waveguide transition section, that is, the length of the wide side of the rectangular waveguide is equal to a1, and the length of the narrow side is equal to b1. The inner and outer chamfers of the nth curved waveguide both adopt a rounded structure, the first chamfer radius is e1, and the second chamfer radius is e2. To facilitate connection with the microwave source, the length of the rectangular waveguide at the output end of the nth curved waveguide is l3. The wide side length a2 and the narrow side length b2 of the rectangular waveguide are generally selected as standard rectangular waveguide sizes covering the microwave operating frequency band. For example, if the operating frequency band is within the S band (2-4GHz), the BJ32 standard rectangular waveguide can be selected. If the operating frequency band is within the X band (8-12GHz), the BJ100 standard rectangular waveguide can be selected.

[0033] It should be noted that the power distribution / combination number N of the present invention should not be too high, because when the number N is too large, the adjacent fan-shaped-rectangular waveguide transition sections of the coaxial waveguide-circumferential rectangular waveguide array transition structure will be close to or even connected together, which is not conducive to processing and manufacturing. Therefore, the number N should generally satisfy 3≤N≤8.

[0034] Through the electromagnetic simulation software CST Studio Suit 2014 version, under the conditions of r0>r1>0, Δr>0, r1≈(r0-Δr) / 2, d1>0, l1>0, h>0, a1>b1>0, Δa>0, -Δa≈r1+(Δr-a1) / 2, e2>e1>0, a2>b2>0, 3≤N≤8, N is an integer, r0 is equal to the inner radius of the circular waveguide of the antenna transmitting system at the back end of the external HPM channel power synthesis system, a2 and b2 are the standard rectangular waveguide sizes covering the microwave operating frequency band, and the transmission efficiency of the distributor / synthesizer is set to be greater than 99%. The parameters r1, Δr, d1, l1, θ can be obtained by optimization. n , a1, b1, Δa, d2, φ n , l2, e2, e1, a2, b2, l3 accurate values. h is generally 2 to 5 mm.

[0035] The working process of the present invention is divided into power distribution and power synthesis.

[0036] The power distribution process is as follows: the conical circular waveguide-coaxial waveguide transition structure converts the TE of the input circular waveguide 01 Mode microwaves are gradually converted into TE in coaxial waveguide 01mode, and then input to the coaxial waveguide-circumferential rectangular waveguide array transition structure; the coaxial waveguide-circumferential rectangular waveguide array transition structure converts the input coaxial waveguide TE 01 The mode microwave is divided into n sector-shaped parts according to the predetermined output power ratio, and the electric field of these N sector-shaped parts is gradually converted into N rectangular waveguide TE 10 mode, and then input it into the circular bend waveguide array; the circular bend waveguide array longitudinally inputs the N rectangular waveguides TE of the coaxial waveguide-circular rectangular waveguide array transition structure 10 Mode microwave conversion into N rectangular waveguide TE 10 The mode is output radially, thus realizing radial power distribution of N waveguides.

[0037] The power synthesis process is the reverse operation of the power allocation process. Specifically, the output powers of N HPM system units are p1, p2, ..., p n ,…,p N The N HPM system units output microwaves to the first output port, the second output port, ..., the nth output port, ..., the Nth output port of the present invention, and after passing through the circular curved waveguide array, they are converted into N longitudinal rectangular waveguides TE 10 The mode microwave is then input to the lower port of the coaxial waveguide-circumferential rectangular waveguide array transition structure; the coaxial waveguide-circumferential rectangular waveguide array transition structure converts the input N longitudinal rectangular waveguide TE 10 Mode microwaves are gradually converted into coaxial waveguide TE 01 mode, and then input to the lower port of the tapered circular waveguide-coaxial waveguide transition structure; the tapered circular waveguide-coaxial waveguide transition structure converts the input coaxial waveguide TE 01 Mode conversion to circular waveguide TE 01 The input port of the present invention is connected to the antenna transmission system at the rear end of the HPM channel power synthesis system, thereby realizing radial power synthesis of N waveguides.

[0038] The present invention can achieve the following beneficial effects:

[0039] (1) The present invention adopts a tapered circular waveguide-coaxial waveguide transition structure to solve the problem that high-overmode circular waveguide direct radial power synthesis is prone to excite high-order modes, broaden the operating frequency band of the power divider / synthesizer, and improve the power carrying capacity, so that the power capacity can reach the GW level.

[0040] (2) The present invention adopts a coaxial waveguide-circumferential rectangular waveguide array transition structure to realize the transition from coaxial waveguide TE to 01 mode microwave to multiple rectangular waveguide TE 10 The smooth conversion of modes avoids the increase of lateral size and effectively improves space utilization.

[0041] (3) The present invention is all metal structure, and there is no discontinuous structure inside the cavity, which can effectively suppress the electric field enhancement effect and further improve its working frequency band and power capacity. BRIEF DESCRIPTION OF THE DRAWINGS

[0042] Figure 1 It is a three-dimensional structural diagram of the present invention.

[0043] Figure 2 for Figure 1 Schematic diagram of the structure of the medium-conical circular waveguide-coaxial waveguide transition structure 1. Figure 2 (a) Yes Figure 1 The three-dimensional structure diagram of the medium-conical circular waveguide-coaxial waveguide transition structure 1, Figure 2 (b) Yes Figure 2 (a) A cross-sectional view of the tapered circular waveguide-coaxial waveguide transition structure 1 along the AA' plane.

[0044] Figure 3 for Figure 1 Schematic diagram of the structure of the coaxial waveguide-circumferential rectangular waveguide array transition structure 2. Figure 3 (a) Yes Figure 1 The three-dimensional structure diagram of the coaxial waveguide-circumferential rectangular waveguide array transition structure 2, Figure 3 (b) Yes Figure 3 (a) is a cross-sectional view of the coaxial waveguide-circumferential rectangular waveguide array transition structure 2 along the BB' plane.

[0045] Figure 4 for Figure 1 Top view of the mid-circumferential bend waveguide array 3.

[0046] Figure 5 The circular waveguide TE in the waveguide cavity of the present invention 01 Mode, coaxial waveguide TE 01 Mode and rectangular waveguide TE 10 Electric field distribution diagram of the mode. Figure 5 (a) is a circular waveguide TE 01 model The electric field distribution diagram, Figure 5 (b) is the coaxial waveguide TE 01 model The electric field distribution diagram, Figure 5 (c) is a rectangular waveguide TE 10 model Electric field distribution diagram.

[0047] Figure 6 1 is a reflection coefficient simulation result of a 7-way waveguide radial power divider / combiner according to an embodiment of the present invention.

[0048] Figure 7 The simulation results of transmission coefficients of output ports Port2, Port3, Port4 and Port5 of a 7-way waveguide radial power divider / synthesizer according to an embodiment of the present invention are shown.

[0049] Figure 8 The diagram is a top view and a cross-sectional view of the electric field distribution of a 7-way waveguide radial power divider / combiner according to an embodiment of the present invention. Figure 8 (a) is the top view of the electric field distribution. Figure 8 (b) Yes Figure 8 (a) is the cross-sectional view of the electric field distribution along the CC' plane and the DD' plane. DETAILED DESCRIPTION

[0050] The technical solution of the present invention is further described in detail below in conjunction with the accompanying drawings, but the protection scope of the present invention is not limited to the following.

[0051] like Figure 1 As shown, a compact high-power circular waveguide radial power distributor / synthesizer is composed of three parts, a conical circular waveguide-coaxial waveguide transition structure 1, a coaxial waveguide-circumferential rectangular waveguide array transition structure 2, and a circular curved waveguide array 3, which are coaxially connected in sequence. These three parts are made of metal materials. The entire power distributor / synthesizer is arranged in a central rotational symmetric layout along the central axis, which can ensure the consistency of the microwave amplitude and phase of each rectangular waveguide output port. The input port of the present invention is labeled Port0, and the output ports are labeled Port1, Port2, ..., Port n , …, Port N N is a positive integer, 1≤n≤N, and the value of N can be determined according to the number of microwave power distribution / synthesis required. The input port Port0 is connected to the antenna transmission system at the back end of the HPM channel power synthesis system, and the N output ports are the first output port Port1, the second output port Port2, ..., the nth output port Port n , ..., Nth output port Port N Each of them is connected to a microwave source module.

[0052] Figure 2 It is a structural diagram of the tapered circular waveguide-coaxial waveguide transition structure 1 of the present invention, Figure 2 (a) is a three-dimensional structural diagram of the tapered circular waveguide-coaxial waveguide transition structure 1, Figure 2 (b) Yes Figure 2 (a) is a cross-sectional view of the tapered circular waveguide-coaxial waveguide transition structure 1 along the AA' plane. The tapered circular waveguide-coaxial waveguide transition structure 1 is composed of a circular waveguide 11, a tapered circular waveguide-coaxial transition waveguide 12 and a coaxial waveguide 13. Figure 2(b), the circular waveguide 11 is a cylinder with an inner radius of r0 and a wall thickness equal to the thickness h of the circular waveguide of the antenna transmitting system at the rear end of the HPM channel power combining system. The circular waveguide 11 is used to transmit the synthesized TE 01 mode microwaves to the antenna transmitting system at the rear end of the HPM channel power combining system. The coaxial waveguide 13 is composed of a first inner conductor 132 coaxially nested inside a first outer conductor 131. The first outer conductor 131 is a cylinder with a length of l1 and a wall thickness equal to h. The first inner conductor 132 is also a cylinder with a length equal to l1, an outer radius of r1, and a wall thickness equal to h; the difference between the inner radius of the first outer conductor 131 and the outer radius of the first inner conductor 132 is Δr. The annular channel between the first inner conductor 132 and the first outer conductor 131 is used to transmit the coaxial waveguide TE 01 mode microwaves. The conical circular waveguide - coaxial transition waveguide 12 is composed of a second outer conductor 121 and a second inner conductor 122. The second outer conductor 121 is in the shape of an inverted frustum of a cone (i.e., the upper port radius is greater than the lower port radius, satisfying r1 + Δr < r0). Its upper port is connected to the lower port of the circular waveguide 11, and the lower port is connected to the upper port of the first outer conductor 131 of the coaxial waveguide 13. The second inner conductor 122 is conical, and its lower port is connected to the upper port of the first inner conductor 132 of the coaxial waveguide 13. The height of the second outer conductor 121 is d1, the radius of the upper port is equal to r0, the radius of the lower port is equal to r1 + Δr, and the wall thickness is equal to h. The height of the second inner conductor 122 is equal to d1, the radius of the lower port is equal to r1, and the wall thickness is equal to h. h is generally taken as 2 - 5 mm.

[0053] The nested funnel - shaped channel between the second inner conductor 122 and the second outer conductor 121 of the conical circular waveguide - coaxial transition waveguide 12 gradually converts the circular waveguide TE 01 mode microwaves input into the circular waveguide 11 into the TE 01 mode of the coaxial waveguide 13. The electric field of the circular waveguide TE 01 mode microwaves is concentrated in the annular region near the radius r0 / 2 from the center of the circular waveguide 11, as shown in Figure 5 (a); the electric field of the coaxial waveguide TE 01 mode microwaves is concentrated in the annular region between the first inner conductor 132 and the first outer conductor 131, as shown in Figure 5 (b). Therefore, to reduce the electric field perturbation during the mode conversion between the circular waveguide TE 01 mode and the coaxial waveguide TE 01 mode, it is required that the electric field concentration regions of the TE 01 mode of the coaxial waveguide 13 and the circular waveguide 11 should match. That is

[0054] r1≈(r0 - Δr) / 2 (1)

[0055] If the coaxial waveguide 13 operates in a low over - mode state (i.e., the coaxial waveguide TE01 Mode transmission, coaxial waveguide TE 02 mode cutoff), the high-order modes generated in the subsequent radial power distribution / synthesis process can be effectively suppressed, thereby achieving the widening of the working bandwidth. Therefore, in order to ensure that the coaxial waveguide 13 works in a low overmode state, the size of the coaxial waveguide 13 (mainly r1, Δr) must meet the following requirements:

[0056]

[0057] It can be calculated by the eigenvalue equation of the coaxial waveguide:

[0058] J′ m (K c r1)N′ m (K c r2)-J′ m (K c r2))N′ m (K c r1)=0 (3)

[0059] in

[0060] r2=r1+Δr

[0061] In the formula, J′ m (K c r1) is the derivative of the first kind Bessel function, and m is the order of the first kind Bessel function. N′ m (K c r2) is the derivative of the second kind Bessel function, m is the order of the second kind Bessel function, r2 is the inner radius of the first outer conductor 131 of the coaxial waveguide 13, K c is the eigenvalue, also known as the cutoff wave number. 01 and TE 02 mode, m = 0. Equation (3) is a transcendental equation, which can generally be solved by numerical methods such as bisection or Newton's method. Equation (3) has countless roots K c , where the first root and Related, the second root and Related:

[0062]

[0063] Given the initial values ​​of r1 and Δr that satisfy r1≈(r0-Δr) / 2, r2=r1+Δr, we can find and like and Satisfying formula (2) indicates that r1 and Δr meet the requirements; if and If equation (2) is not satisfied, adjust r1 and Δr until the equation (3) and (4) are obtained. and Satisfying formula (2), the adjusted r1 and Δr are r1 and Δr that meet the design indicators.

[0064] Figure 3 is a structural diagram of a coaxial waveguide-circumferential rectangular waveguide array transition structure 2, Figure 3 (a) Yes Figure 1 The three-dimensional structure diagram of the coaxial waveguide-circumferential rectangular waveguide array transition structure 2, Figure 3 (b) is a cross-sectional view of the coaxial waveguide-circumferential rectangular waveguide array transition structure 2 along the BB' plane. The coaxial waveguide-circumferential rectangular waveguide array transition structure 2 is composed of N fan-shaped-rectangular waveguide transition sections, namely the first fan-shaped-rectangular waveguide transition section 21, ..., the nth fan-shaped-rectangular waveguide transition section 2n, ..., the Nth fan-shaped-rectangular waveguide transition section 2N, which are arranged around the central axis OO' of the present invention. The upper end of the coaxial waveguide-circumferential rectangular waveguide array transition structure 2 is an annular section formed by N fans around a circle, which is connected to the lower end of the coaxial waveguide 13. The outer radius of the annular section is equal to the outer radius of the coaxial waveguide 13, the inner radius is equal to r1+Δr, and the wall thickness is equal to h. The lower end of the coaxial waveguide-circumferential rectangular waveguide array transition structure 2 is a section formed by N rectangles of the same size around the central axis OO', which is connected to the upper end of the circular curved waveguide array 3. The N sector-rectangular waveguide transition sections are all formed by the linear transition between the sector at the upper end and the rectangle at the lower end. The opening angles of the N sectors are θ1, θ2, …, θ n ,…,θ N The nth fan angle θ n The size of corresponds to the output power of the rectangular waveguide output port connected to it. If the output power of the N rectangular waveguide output ports of the present invention is p1, p2, ..., p n ,…,p N , the nth fan angle θ n for:

[0065]

[0066] θ1,θ2,…,θ n ,…,θ N The dimensions of the remaining parts of the N sector-rectangular waveguide transition sections are not equal, but the dimensions of the remaining parts of the N sector-rectangular waveguide transition sections are equal. Therefore, the characteristics of the remaining parts of the sector-rectangular waveguide transition section are described by taking the nth sector-rectangular waveguide transition section 2n as a representative. Figure 3(b), the height of the fan-shaped-rectangular waveguide transition section 2n is d2, the length of the lower rectangle is a1, and the width is b1. In order to ensure that the fan-shaped-rectangular waveguide transition section 2n has a high microwave transmission efficiency, the lower rectangle should be located directly below the fan as much as possible. Satisfy:

[0067] Δa≈r1+(Δr-a1) / 2 (6)

[0068] Wherein, Δa is the distance from the lower end rectangle of the sector-rectangular waveguide transition section 2n to the central axis OO'.

[0069] At the same time, a1 and b1 should also meet the main mode (TE 10 Mode) Transmission conditions:

[0070]

[0071] In the formula, max(a1,2b1) means taking the maximum value of a1 and 2b1.

[0072] The function of the coaxial waveguide-circumferential rectangular waveguide array transition structure 2 is to convert the coaxial waveguide 13 input TE 01 The mode microwave is converted into N rectangular waveguide TEs in the longitudinal direction 10 Mode output, rectangular waveguide TE 10 The electric field distribution of the mode is Figure 5 (c) and make these N rectangular waveguides TE 10 The power of the mode microwaves is equal to the output power of the power divider / synthesizer p1, p2, ..., p n ,…,p N The height d2 of the fan-shaped-rectangular waveguide transition section has a significant impact on the conversion efficiency. Generally speaking, the larger d2 is, the higher the conversion efficiency is. However, in actual design, a trade-off needs to be made between the transmission efficiency and d2. Therefore, d2 is generally selected as the working wavelength range, that is,

[0073] like Figure 4 As shown, the circular curved waveguide array 3 is composed of N H-plane 90° curved waveguides of the same structure, namely, the first curved waveguide 31, ..., the nth curved waveguide 3n, ..., the Nth curved waveguide 3N, which are evenly arranged along the circumference. The upper ends of these N curved waveguides are connected to the lower ends of the N fan-shaped-rectangular waveguide transition sections of the coaxial waveguide-circumferential rectangular waveguide array transition structure 2, that is, the upper end of the nth curved waveguide 3n is connected to the lower end of the nth fan-shaped-rectangular waveguide transition section 2n. Therefore, the angle φ between the nth curved waveguide 3n and the n+1th curved waveguide 3(n+1) is n satisfy:

[0074]

[0075] The main function of the circular bend waveguide array 3 is to connect the N rectangular waveguides TE longitudinally inputted from the coaxial waveguide to the circular rectangular waveguide array transition structure 2 through N H-plane 90° bend waveguides. 10 Mode microwave conversion to rectangular waveguide TE 10 mode is radially output, thereby realizing radial power distribution / synthesis of N waveguides. Because the structures of the N curved waveguides are the same, the nth curved waveguide 3n is used as a representative to describe the characteristics of the curved waveguide. There is a rectangular waveguide at the upper end of the nth curved waveguide 3n, which is connected to the rectangle at the lower end of the fan-shaped-rectangular waveguide transition section 2n. The length of the rectangular waveguide at the upper end of the nth curved waveguide 3n is l2, and the size of the rectangular waveguide is the same as the size of the rectangle at the lower end of the fan-shaped-rectangular waveguide transition section 2n, that is, the length of the wide side of the rectangular waveguide is equal to a1, and the length of the narrow side is equal to b1. The inner and outer chamfers of the nth curved waveguide 3n both adopt a rounded structure, the first chamfer radius is e1, and the second chamfer radius is e2. To facilitate connection with the microwave source, the length of the rectangular waveguide at the output end of the nth curved waveguide 3n is l3. The wide side length a2 and the narrow side length b2 of the rectangular waveguide are generally selected as standard rectangular waveguide sizes covering the microwave operating frequency band range. For example, if the operating frequency band is within the S band (2-4GHz), the BJ32 standard rectangular waveguide can be selected. If the operating frequency band is within the X band (8-12GHz), the BJ100 standard rectangular waveguide can be selected.

[0076] It should be noted that the power distribution / combination number N of the present invention should not be too high, because when the number N is too large, the adjacent fan-shaped-rectangular waveguide transition sections of the coaxial waveguide-circumferential rectangular waveguide array transition structure 2 will be close to or even connected together, which is not conducive to processing and manufacturing. Therefore, the number N should generally satisfy 3≤N≤8.

[0077] The working process of the present invention is divided into power distribution and power synthesis.

[0078] The power distribution process is as follows: the conical circular waveguide-coaxial waveguide transition structure 1 converts the TE of the input circular waveguide 11 01 Mode microwaves are gradually converted into TE in the coaxial waveguide 13 01 mode, and then input to the coaxial waveguide-circumferential rectangular waveguide array transition structure 2; the coaxial waveguide-circumferential rectangular waveguide array transition structure 2 converts the input coaxial waveguide TE 01 The mode microwave is divided into n sector-shaped parts according to the predetermined output power ratio, and the electric field of these N sector-shaped parts is gradually converted into N rectangular waveguide TE 10 mode, and then input to the circular bend waveguide array 3; the circular bend waveguide array 3 longitudinally inputs the N rectangular waveguides TE of the coaxial waveguide-circumferential rectangular waveguide array transition structure 2 10 Mode microwave conversion into N rectangular waveguide TE 10 The mode is output radially, thus realizing radial power distribution of N waveguides.

[0079] The power synthesis process is the reverse operation of the power distribution process, specifically: the first output port Port1, the second output port Port2, ..., the nth output port Port n , ..., Nth output port Port N They are connected to N HPM system units respectively. The output powers of the N HPM system units are p1, p2, ..., p n ,…,p N , the output phases are equal. N HPM system units output microwaves to the first output port Port1, the second output port Port2, ..., the nth output port Port n , ..., Nth output port Port N , after passing through the circular bend waveguide array 3, it is converted into N longitudinal rectangular waveguides TE 10 The mode microwave is then input to the lower port of the coaxial waveguide-circumferential rectangular waveguide array transition structure 2; the coaxial waveguide-circumferential rectangular waveguide array transition structure 2 converts the input N longitudinal rectangular waveguides TE 10 Mode microwaves are gradually converted into coaxial waveguide TE 01 mode, and then input to the lower port of the conical circular waveguide-coaxial waveguide transition structure 1; the conical circular waveguide-coaxial waveguide transition structure 1 converts the input coaxial waveguide TE 01 Mode conversion to circular waveguide TE 01 mode, and outputted at the input port Port0 of the present invention. The input port Port0 is connected to the antenna transmission system at the rear end of the HPM channel power synthesis system, thereby realizing radial power synthesis of N waveguides.

[0080] Example 1

[0081] The following are the X-band (frequency range is 8-12 GHz, corresponding to the microwave wavelength range of 37.50-25.00 mm, λ mid =30.00mm) of 7 (i.e. N = 7) waveguide radial equal power divider / combiner of an embodiment of the specific design size (f min =8GHz, f max =12GHz):

[0082] According to the application scenario, the radius r0 of the circular waveguide 11 is 44 mm. According to the working frequency band, the rectangular waveguides of the coaxial waveguide-circumferential rectangular waveguide array transition structure 2 and the output port of the circular curved waveguide array 3 are both selected as BJ100 standard rectangular waveguides (a1×b1=a2×b2=22.86mm×10.16mm). According to the equal power distribution / synthesis requirements, θ is calculated by equations (5) and (8): n =φ n≈51.43°, n=1,2,…,7. According to the aforementioned power divider / combiner size requirements, the main parameters of the power divider / combiner are obtained by optimizing the electromagnetic simulation software CST Studio Suit 2014 version as shown in Table 1. After calculation, the lateral size of the power divider / combiner of this embodiment is about 3.2λ mid (Background technology Chu Qingxin et al. of South China University of Technology proposed a method based on low over-mode (TE 02 Mode cutoff) circular waveguide TE 01 High mode isolation radial power divider / combiner with lateral dimensions exceeding 4.1λ mid ).

[0083] Table 1

[0084] Structural parameters <![CDATA[d1]]> <![CDATA[r1]]> Δr <![CDATA[l1]]> <![CDATA[d2]]> h Δa <![CDATA[l2]]> <![CDATA[e1]]> <![CDATA[e2]]> <![CDATA[l3]]> Dimensions (mm) 40 12.5 22.86 20 26 2 12.5 7.14 6 30 5

[0085] The power divider / synthesizer of this embodiment is a high over-mode waveguide device. When the microwave operating frequency reaches 12.5 GHz, the circular waveguide 11 can theoretically support 64 modes (including various degenerate modes) for effective transmission. 01 The simulation results of reflection coefficient and transmission coefficient of this embodiment are shown as follows: Figure 6 and Figure 7 As shown. Figure 6 It can be seen that in the frequency range of 8.6-12.5GHz, the power splitter / synthesizer mainly exists in circular waveguide and The reflection signals of the modes are all smaller than -20dB. Figure 7 It can be seen that in the frequency range of 8.6-12.5GHz, the transmission coefficient amplitude of the output port is within the range of -8.5±0.05dB, that is, the amplitude imbalance is less than 0.1dB, and the output phase of each port is almost the same. That is, the working bandwidth of this embodiment reaches 37% (Background Technology Chu Qingxin et al. of South China University of Technology proposed a method based on low overmode (TE 02 Mode cutoff) circular waveguide TE 01 The high isolation radial power distribution / synthesizer has a maximum working bandwidth of 25% and a synthesis efficiency of more than 97.7% (Background technology José R. Montejo-Garai et al., Information Processing and Telecommunications Center of the Political Academy of Madrid, Spain, proposed a method based on low overmode (TE 02 Mode cutoff) circular waveguide TE 01 The 16-way Ku-band radial power splitter / combiner in the mode has a maximum transmission efficiency of 96.4%).

[0086] Figure 8The simulation results of the electric field distribution characteristics of Example 1 at an operating frequency of 10 GHz when the input microwave power is 0.5 W are shown. Figure 8 (a) It can be seen that Example 1 can effectively realize the circular waveguide Mode - Coaxial Waveguide TE 01 model -Multi-channel rectangular waveguide Mode conversion. Figure 8 As shown in (b), the maximum electric field amplitude E 0.5W is 843V / m. According to the electric field breakdown threshold E under vacuum conditions b is 700kV / cm, The power capacity P of the power divider / combiner under vacuum conditions is calculated. b It can reach 3.45GW. These simulation results show that the power divider / combiner has the advantages of wide working frequency band, high synthesis efficiency, large power capacity, small lateral size, etc., and has extremely high practical value in the technical field of HPM channel power synthesis.

[0087] The above is only a preferred embodiment of the present invention. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the technical principles of the present invention. These improvements and modifications should also be regarded as the scope of protection of the present invention.

Claims

1. A compact high power waveguide radial power splitter / combiner, characterized in that The compact high-power circular waveguide radial power distributor / synthesizer is composed of three parts, namely a conical circular waveguide-coaxial waveguide transition structure (1), a coaxial waveguide-circumferential rectangular waveguide array transition structure (2) and a circular curved waveguide array (3), which are sequentially coaxially connected; the three parts are all made of metal materials; the entire power distributor / synthesizer is arranged in a central rotation symmetrical manner along the central axis; the input port (Port0) of the compact high-power waveguide radial power distributor / synthesizer is connected to the antenna transmission system at the rear end of the HPM channel power synthesis system, and the N output ports, namely the first output port (Port1), the second output port (Port2), ..., the nth output port (Port n ), ..., Nth output port (Port N ) are respectively connected to a microwave source module, N is a positive integer, 1≤n≤N; the HPM refers to high power microwave; The conical circular waveguide - coaxial waveguide transition structure (1) consists of a circular waveguide (11), a conical circular waveguide - coaxial transition waveguide (12), and a coaxial waveguide (13); the circular waveguide (11) is a cylinder with an inner radius of r0 and a wall thickness equal to the thickness h of the circular waveguide of the antenna transmitting system at the rear end of the HPM channel power combining system. The circular waveguide (11) is used to transmit the synthesized TE 01 mode microwave to the antenna transmitting system at the rear end of the HPM channel power combining system; the coaxial waveguide (13) is composed of a first inner conductor (132) coaxially nested inside a first outer conductor (131); the first outer conductor (131) is a cylinder with a length of l1 and a wall thickness equal to h, and the first inner conductor (132) is also a cylinder with a length equal to l1, an outer radius of r1, and a wall thickness equal to h; the difference between the inner radius of the first outer conductor (131) and the outer radius of the first inner conductor (132) is Δr; the annular channel between the first inner conductor (132) and the first outer conductor (131) is used to transmit the coaxial waveguide TE 01 mode microwave; the conical circular waveguide - coaxial transition waveguide (12) is composed of a second outer conductor (121) and a second inner conductor (122); the second outer conductor (121) is in the shape of an inverted frustum of a cone, its upper port is connected to the lower port of the circular waveguide (11), and its lower port is connected to the upper port of the first outer conductor (131) of the coaxial waveguide (13); the second inner conductor (122) is conical, its lower port is connected to the upper port of the first inner conductor (132) of the coaxial waveguide (13); the height of the second outer conductor (121) is d1, the radius of the upper port is equal to r0, the radius of the lower port is equal to r1 + Δr, r1 + Δr < r0, and the wall thickness is equal to h; the height of the second inner conductor (122) is equal to d1, the radius of the lower port is equal to r1, and the wall thickness is equal to h; The nested funnel-shaped channel between the second inner conductor (122) and the second outer conductor (121) of the conical circular waveguide-coaxial transition waveguide (12) inputs the circular waveguide TE of the circular waveguide (11) into the 01 The mode microwaves are gradually converted into TE in the coaxial waveguide (13) 01 Mode: Circular waveguide TE 01 The electric field of the mode microwave is concentrated in the annular region near the radius r0 / 2 from the center of the circular waveguide (11). 01 The mode microwave electric field is concentratedly distributed in the annular region between the first inner conductor (132) and the first outer conductor (131); the TE of the coaxial waveguide (13) and the circular waveguide (11) is required to be 01 The mode electric field concentration area matches; The coaxial waveguide-circumferential rectangular waveguide array transition structure (2) is composed of N fan-shaped-rectangular waveguide transition sections, namely the first fan-shaped-rectangular waveguide transition section (21), ..., the nth fan-shaped-rectangular waveguide transition section (2n), ..., the Nth fan-shaped-rectangular waveguide transition section (2N), which are arranged around the central axis OO' of the compact high-power waveguide radial power distributor / synthesizer; the upper end of the coaxial waveguide-circumferential rectangular waveguide array transition structure (2) is an annular section formed by the N fans around the circle, which is connected to the coaxial waveguide ( 13); the outer radius of the annular section is equal to the outer radius of the coaxial waveguide (13), the inner radius is equal to r1+Δr, and the wall thickness is equal to h; the lower end of the coaxial waveguide-circumferential rectangular waveguide array transition structure (2) is a section formed by N rectangles of the same size around the central axis OO', and is connected to the upper end of the circular curved waveguide array (3); the N sector-rectangular waveguide transition sections are all formed by linear transition between the sector at the upper end and the rectangle at the lower end; the opening angles of the N sectors are θ1, θ2, ..., θ n ,…,θ N ; The nth fan angle θ n The size of corresponds to the output power of the rectangular waveguide output port connected to it; let the output power of N rectangular waveguide output ports be p1, p2, …, p n ,…,p N , the nth fan angle θ n for: N sector-rectangular waveguide transition sections except θ1,θ2,…,θ n ,…,θ N The dimensions of the remaining parts are all equal except for the above. The height of the nth sector-rectangular waveguide transition section (2n) is d2, the length of the lower rectangle is a1, and the width is b1. The function of the coaxial waveguide-circumferential rectangular waveguide array transition structure (2) is to convert the TE input by the coaxial waveguide (13) 01 The mode microwave is converted into N rectangular waveguide TEs in the longitudinal direction 10 mode output, and make these N rectangular waveguide TE 10 The power of the mode microwaves is equal to the output power of the power divider / synthesizer p1, p2, ..., p n ,…,p N ; The circular curved waveguide array (3) is composed of N H-plane 90° curved waveguides with the same structure, namely, the first curved waveguide (31), ..., the nth curved waveguide (3n), ..., the Nth curved waveguide (3N), which are evenly arranged along the circumference. The upper ends of the N curved waveguides are connected to the lower ends of the N fan-shaped-rectangular waveguide transition sections of the coaxial waveguide-circumferential rectangular waveguide array transition structure (2); the angle φ between the nth curved waveguide (3n) and the n+1th curved waveguide 3(n+1) is n satisfy: The circular curved waveguide array (3) vertically inputs the coaxial waveguide-circumferential rectangular waveguide array transition structure (2) through N H-plane 90° curved waveguides into the N rectangular waveguide TE 10 Mode microwave conversion to rectangular waveguide TE 10 The mode is radially output, thereby realizing N-way waveguide radial power distribution / synthesis; the upper end of the nth curved waveguide (3n) is provided with a section of rectangular waveguide, which is connected to the rectangle at the lower end of the fan-shaped-rectangular waveguide transition section (2n); the length of the rectangular waveguide at the upper end of the nth curved waveguide (3n) is l2, the length of the wide side of the rectangular waveguide at the upper end of the nth curved waveguide (3n) is equal to a1, and the length of the narrow side is equal to b1; the inner and outer chamfers of the nth curved waveguide (3n) both adopt a rounded structure, the first chamfer radius is e1, and the second chamfer radius is e2; the length of the rectangular waveguide at the output end of the nth curved waveguide (3n) is l3, and the length of the wide side a2 and the length of the narrow side b2 of the rectangular waveguide at the output end are selected as standard rectangular waveguide sizes covering the microwave working frequency band range.

2. A compact high power waveguide radial power splitter / combiner as claimed in claim 1, characterized in that The power allocation / synthesis number N satisfies 3≤N≤8.

3. A compact high power waveguide radial power splitter / combiner as claimed in claim 1, characterized in that The r0 is equal to the inner radius of the circular waveguide of the antenna transmitting system at the rear end of the external HPM channel power synthesis system, and the r1 and Δr satisfy r1≈(r0-Δr) / 2r0.

4. A compact high power waveguide radial power splitter / combiner as claimed in claim 3, characterized in that The r1 and Δr satisfy: In formula (2), c0 is the propagation speed of light in free space, f min The minimum frequency of the operating frequency band set by the user, f max The maximum frequency of the working frequency band set by the user; is the TE of the coaxial waveguide (13) 01 Mode cut-off wavelength, is the TE of the coaxial waveguide (13) 02 The mode cutoff wavelength is calculated by formula (3): J′ m (K c r1)N′ m (K c r2)-J′ m (K c r2))N′ m (K c r1)=0 (3) in r2=r1+Δr In the formula, J′ m (K c r1) is the derivative of the first kind Bessel function, m is the order of the first kind Bessel function; N′ m (K c r2) is the derivative of the second kind Bessel function, m is the order of the second kind Bessel function, r2 is the inner radius of the first outer conductor (131) of the coaxial waveguide (13), K c is the eigenvalue; for TE 01 and TE 02 mode, m = 0; Equation (3) is a transcendental equation, which can be solved by using the bisection method or Newton method. There are countless roots K c , where the first root and Related, the second root and Related: Given the initial values ​​of r1 and Δr that satisfy r1≈(r0-Δr) / 2, r2=r1+Δr, we can find and like and Satisfying formula (2) indicates that r1 and Δr meet the requirements; if and If equation (2) is not satisfied, adjust r1 and Δr until the equation (3) and (4) are obtained. and Satisfying formula (2), the adjusted r1 and Δr are r1 and Δr that meet the design indicators.

5. A compact high power waveguide radial power divider / combiner as claimed in claim 1, characterized in that The lower end rectangle of the sector-rectangular waveguide transition section (2n) is located directly below the sector.

6. A compact high power waveguide radial power splitter / combiner as claimed in claim 4, characterized in that The length a1 and width b1 of the lower end rectangle of the nth fan-shaped-rectangular waveguide transition section (2n) satisfy: Δa≈r1+(Δr-a1) / 2(6) In formula (6), Δa is the distance between the lower end rectangle of the fan-shaped-rectangular waveguide transition section (2n) and the central axis OO'; At the same time, a1 and b1 also meet the TE requirements within the microwave operating frequency band. 10 Mode transmission conditions: In formula (7), max(a1,2b1) means taking the maximum value of a1 and 2b1; The height d2 of the nth sector-rectangular waveguide transition section (2n) satisfies 7. A compact high power waveguide radial power splitter / combiner as claimed in claim 1, characterized in that When the operating frequency band is within the S band, the rectangular waveguide at the output end of the nth curved waveguide (3n) is a BJ32 standard rectangular waveguide; when the operating frequency band is within the X band, the rectangular waveguide at the output end of the nth curved waveguide (3n) is a BJ100 standard rectangular waveguide.

8. A compact high power waveguide radial power divider / combiner as claimed in claim 6, characterized in that The h is 2 to 5 mm; the r1, Δr, d1, l1, θ n , a1, b1, Δa, d2, φ n The exact values ​​of l2, e2, e1, a2, b2, and l3 are determined by the electromagnetic simulation software CST Studio Suit. When r0>r1>0, Δr>0, r1≈(r0-Δr) / 2 are satisfied, d1>0, l1>0, h>0, a1>b1>0, Δa>0, Δa≈r1+(Δr-a1) / 2, d2>0, l2>0, e2>e1>0, a2>b2>0, 3≤N≤8, N is an integer, r0 is equal to the inner radius of the circular waveguide of the antenna transmitting system at the rear end of the external HPM channel power synthesis system, a2 and b2 meet the standard rectangular waveguide size covering the microwave operating frequency band, and the transmission efficiency of the distributor / synthesizer is set to be greater than 99%. r1, Δr, d1, l1, θ are obtained by optimization. n , a1, b1, Δa, d2, φ n , l2, e2, e1, a2, b2, l3’s exact values.

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