Triple-band high-power microwave rectangular waveguide slot antenna

Abstract

The present invention discloses a three-band high-power microwave rectangular waveguide slot antenna, the purpose of which is to solve the problem of C / X / Ku three-band microwave radiation. The present invention is composed of N electromagnetic band gaps, a slotted ridge waveguide and a concave waveguide. The N electromagnetic band gaps are periodically distributed on both sides of the slotted ridge waveguide in the order from C / X dual-band microwave input to output; one end of the slotted ridge waveguide opening is connected to the microwave source as the input port of the C / X dual-band high-power microwave waveguide slot array antenna; one end of the concave waveguide opening is connected to the microwave source as the input port of the Ku-band high-power microwave waveguide slot array antenna, and the input port of the Ku-band high-power microwave waveguide slot array antenna is the output port of the C / X dual-band high-power microwave waveguide slot array antenna. The present invention uses a single waveguide to achieve C / X / Ku three-band microwave radiation, solving the problems of high-power microwave antennas being difficult to apply in the C / X / Ku bands and having limited power capacity.

Description

Technical Field

[0001] The invention relates to a radiation antenna in the technical field of high-power microwaves, in particular to a high-power microwave rectangular waveguide slot antenna operating in three frequency bands. Background Art

[0002] High-power microwave (HPM) generally refers to strong electromagnetic radiation with a frequency of 300MHz to 300GHz, a peak power greater than 100MW or an average power greater than 1MW. Antennas, as the terminals of high-power microwave systems, are important components for achieving effective directional radiation of microwaves. As high-power microwave systems develop towards cross-band tunability, how to use a set of antennas to radiate the HPMs of different bands generated by them has become a difficult problem that researchers urgently need to solve.

[0003] Rectangular waveguide slot antennas have been widely used in the field of high-power microwaves due to their simple structure and convenient array formation. Currently, there are two methods for using rectangular waveguide slot antennas to achieve dual-band radiation: one is to make full use of the gaps between waveguides and interweave the radiation waveguides of different bands. For example, a dual-frequency (30 GHz / 35 GHz) dual-polarization waveguide slot array antenna designed by Li Teng et al. of Southeast University that works in the Ka-band (see the paper Design and Implementation of Dual-Frequency Dual-Polarization Slotted Waveguide Antenna Array for Ka-Band Application published by Li Teng et al. in IEEE Antennas & Wireless Propagation Letters, 2014, pages 1317-1320), is a staggered arrangement of two antenna waveguides, both of which are fed by slot waveguides, and do not affect each other. A gain of 24.8 dB can be achieved at 30 GHz and a gain of 25.4 dB can be achieved at 35 GHz, but the power capacity of this feeding method is not high, which will affect the power capacity of the entire system; for example, a circular aperture waveguide slot array antenna that works in the C / Ku dual band designed by China Aerospace Science and Industry Corporation (see L. Shi et al. in 2018 12th International Symposium on Antennas, Propagation and EM Theory, 2018, pp. 1-3, A Novel Shared Aperture Dual-Band Slot Array, in which the C-band radiating waveguides are interwoven between the Ku-band radiating waveguides, and the radiating slots of the two bands are both wide-side longitudinal slots. Experimental measurements show that the Ku-band array can achieve 28.6dB gain and 200MHz bandwidth, and the C-band can achieve 17.8dB gain and 120MHz bandwidth.

[0004] The other method is to make full use of the part of the low-frequency waveguide surface that does not participate in the radiation, and to set up the high-frequency radiation waveguide above the low-frequency radiation waveguide. For example, Rao Yuru and others from the 38th Institute of China Electronics Technology Group Corporation designed a dual-band common-aperture waveguide slot antenna operating in the Ku / Ka band (see Rao Yuru et al.'s 2019 invention patent, a dual-frequency common-aperture waveguide slot antenna), in which the Ka-band antenna is mounted above the Ku-band antenna, and each Ku-band radiating waveguide corresponds to two Ka-band radiating waveguides. Both bands use a wide-side longitudinal slit opening method. The simulation results show that the Ku-band radiating array can achieve a gain of 23dB and a relative bandwidth of 2.5%, and the Ka-band radiating array can achieve a gain of 32dB and a relative bandwidth of 1.1%. The antenna uses waveguide for feeding, and this feeding method can achieve high power capacity and has the potential to be applied in the field of high-power microwaves; for example, Chen Ming and others from the East China Institute of Electronic Engineering designed a dual-band antenna operating in the C / L band (see Chen Ming et al.'s paper Dual-Band Dual-Polarized Waveguide Slot Antenna Array for SARApplications), the design idea is to place the L-band radiating waveguide with a longitudinal slot at the bottom, and alternately place the C-band radiating waveguide with a V-shaped slot and the C-band radiating waveguide with a longitudinal slot on the L-band radiating waveguide, respectively. The L-band array can achieve a gain of 25.94dB, with a relative bandwidth of 11.36%, and the two polarizations of the C-band can achieve 38.63dB and 38.64dB gains, with a relative bandwidth of 5.1%. The antenna is fed by a coaxial probe, and the power capacity of this feeding method is not high, and it cannot be directly applied to the high-power microwave field; M. Khorramizadeh et al. of Shahed University in Iran designed a dual-band waveguide slot array antenna working in X / Ka (see the paper published by M. Khorramizadeh et al. in IET Microwaves Antennas & Propagation, 2018, page 12) Cross-polarization reduction), both bands use a wide-side longitudinal slot opening method, and the Ka-band antenna is placed between the slots of the X-band radiation. However, this arrangement will prevent the X-band slot from having enough offset space to change the coupling amount. The antenna can achieve 14dBi gain in the X-band and 19dBi gain in the Ka-band. The antenna is fed through a coaxial connector, and its feeding structure cannot adapt to high-power working environments.

[0005] The essence of these two methods is to combine radiating antennas of different frequency bands to achieve dual-band radiation. However, if the above two methods are directly applied to the design of C / X / Ku three-band antennas, due to the large frequency span, the grating lobe problem caused by the waveguide spacing will be more prominent in the high frequency band, and it is difficult to complete the array under the harsh space constraints, which makes the design of C / X / Ku band waveguide slit array antenna difficult to achieve. At the same time, the feeding methods used by the existing multi-band waveguide slit array antennas do not consider the power capacity requirements and cannot be directly applied to the HPM field. With the continuous deepening of the research on cross-band tunable HPM sources, the research on multi-band HPM antenna feeding technology is very scarce, and the HPM system is widely used in the fields of plasma heating, high-power microwave directed energy weapons, high-power radar, high-energy particle RF acceleration, etc. In addition, using a set of antennas to radiate the HPM of different bands generated by it has important application value for the development of cross-band tunable high-power microwave systems. Therefore, how to provide a waveguide slot array antenna and its corresponding feeding system that can operate in the C / X / Ku triple frequency bands, has high power capacity, and can be applied to the HPM field has become a difficult problem that researchers urgently need to solve. Summary of the invention

[0006] The technical problem to be solved by the present invention is that the C / X / Ku triple-band microwave radiation cannot be realized at present. A novel triple-band high-power microwave rectangular waveguide slot antenna is provided. The antenna has a compact structure, and a single waveguide can radiate C / X dual-band microwave bands in partitions. The Ku-band antenna is erected above the C / X-band antenna, which solves the problems that the current high-power microwave antenna is difficult to apply in the C / X / Ku bands and has limited power capacity.

[0007] The technical solution adopted by the present invention to solve its technical problem is:

[0008] The present invention is composed of N electromagnetic band gaps, a slotted ridge waveguide and a concave waveguide; the end of the slotted ridge waveguide close to a microwave source is defined as a C / X dual-band microwave input end, and the end away from the microwave source is defined as a C / X dual-band microwave output end; the end of the concave waveguide close to the microwave source is defined as a Ku-band microwave input end, and the end away from the microwave source is defined as a Ku-band microwave output end; the N electromagnetic band gaps are periodically distributed on both sides of the interior of the slotted ridge waveguide in the order from C / X dual-band microwave input to output; one end of the slotted ridge waveguide opening is connected to the microwave source as the input port of the C / X dual-band high-power microwave waveguide slot array antenna, and the other end is a closed structure; the N electromagnetic band gaps are connected and fixed to the slotted ridge waveguide by screws, and N is a positive integer; one end of the concave waveguide opening is connected to the microwave source as the input port of the Ku-band high-power microwave waveguide slot array antenna, and the other end is a closed structure;

[0009] The slotted ridge waveguide is composed of a slotted waveguide, a metal ridge, M reflection rods, and a slotted ridge waveguide wall, all of which are made of metal materials; M is a positive integer;

[0010] The concave waveguide is composed of two identical rectangular waveguides, a concave waveguide bottom plate, and a concave waveguide wall, all of which are made of metal materials;

[0011] The slotted waveguide consists of three parts: a first rectangular bottom plate, two first rectangular middle plates, and two first rectangular upper plates; a central axis OO' of the first rectangular channel is drawn along the C / X dual-band microwave input to output direction, point O is on the C / X dual-band microwave input end surface, and point O' is on the slotted ridge waveguide wall; a longitudinal axis AA' is drawn through point O on the C / X dual-band microwave input end surface, AA' is perpendicular to the first rectangular bottom plate, the end away from the first rectangular bottom plate, i.e., end A, is the upper end, and the end close to the first rectangular bottom plate, i.e., end A', is the lower end; a transverse axis BB' is drawn through point O on the C / X dual-band microwave input end surface, the transverse axis BB' is perpendicular to the longitudinal axis AA', end B is the left end, and end B' is the right end; a width a1 of the slotted waveguide is less than the free space wavelength;

[0012] The first rectangular bottom plate is a cuboid plate, with a width equal to a1, a height equal to b1, and a length equal to L0; the lower surfaces of the two first rectangular middle plates are welded to the left and right ends of the upper surface of the first rectangular bottom plate along the direction of the central axis OO', symmetrically about the central axis OO'; the first rectangular middle plate is a cuboid plate, with a width of a2, a height of b2, and a length equal to L0; the lower surfaces of the two first rectangular upper plates are aligned with the end faces away from the AA' axis along the direction of the central axis OO', and are symmetrically welded to the upper surfaces of the two first rectangular middle plates respectively; the first rectangular upper plate is a cuboid plate, with a width of a7, a height of b3, and a length equal to L0; the surfaces of the first rectangular bottom plate, the two first rectangular middle plates, and the first rectangular upper plate close to the axis OO' are inner surfaces;

[0013] The two rectangular waveguides are exactly the same. The two rectangular waveguides are symmetrically attached to the inner surfaces of the two first rectangular upper plates along the central axis OO' direction. The rectangular waveguides separate the wall current of the X-band and the C-band gap to avoid the interference of the C-band gap on the X-band microwave transmission and radiation. The rectangular waveguide consists of a second rectangular bottom plate, two second rectangular middle plates, and a second rectangular upper plate. The lower surface of the second rectangular bottom plate of the rectangular waveguide is aligned with the lower surface of the first rectangular upper plate. The second rectangular bottom plate, the two second rectangular middle plates, and the second rectangular upper plate together form a second The second rectangular channel has a width of a8, a height of b8, and a length of L0; the concave waveguide bottom plate connects the two second rectangular bottom plates of the two rectangular waveguides, and the lower surface of the concave waveguide bottom plate is aligned with the lower surface of the second rectangular bottom plate; the first rectangular bottom plate, the two first rectangular middle plates, the two first rectangular upper plates, the two second rectangular bottom plates of the two rectangular waveguides, and the concave waveguide bottom plate together form a first rectangular channel, the width of the first rectangular channel is a4, the height is equal to b2, and the length is equal to L0, a4=a1-2*a2;

[0014] The second rectangular bottom plate is a rectangular plate with a width of a6, a height of c2, and a length of L0; the lower surfaces of the two second rectangular middle plates are welded to the left and right ends of the upper surface of the second rectangular bottom plate along the direction of the central axis OO'; the second rectangular middle plate is a rectangular plate with a width of c2, a height of b8, and a length of L0; the end surface of the second rectangular upper plate away from the AA' axis along the direction of the central axis OO' is aligned with the second rectangular middle plate, and is welded to the upper surfaces of the two second rectangular middle plates; the second rectangular upper plate is a rectangular plate with a width of a6, a height of c2, and a length of L0; the concave waveguide bottom plate and the two second rectangular middle plates on both sides of the central axis OO' form a first through groove, the depth of the first through groove is c1, and the lateral width is a3;

[0015] The concave waveguide bottom plate is provided with an X-band slot along the AA' direction; the first rectangular upper plate is provided with a C-band slot along the AA' direction; the second rectangular upper plate is provided with a Ku-band slot along the AA' direction; the X-band slot is capsule-shaped, with a total of K1, a width of w2, a length of L2, a depth of c2, rounded corners at both ends, and a chamfer radius of r4; the X-band slot is provided on the bottom surface of the first through slot, divided into two rows, and staggeredly distributed on the left and right sides of OO' along the central axis OO' direction, the lateral spacing between adjacent X-band slots is q3, the axial spacing is p3, and the axial spacing between the X-band slot closest to the C / X dual-band microwave input end face and the C / X dual-band microwave input end face is s3; the C-band slot 216 is provided with a The upper part is rectangular, and the lower part is fine capsule-shaped. There are K2 of them in total, which are divided into two rows and staggered in the two first rectangular upper plates on the left and right sides of OO' along the central axis OO'. The width of the rectangular part of the C-band slot is w3, the length is L3, and the depth is equal to c1. The rectangular part of the C-band slot is chamfered at both ends of the side wall away from OO', and the chamfer radius is R5. The width of the fine capsule-shaped part of the C-band slot is w4, the length is L4, the depth is equal to c2, and the two ends are chamfered, and the chamfer radius is equal to R6. The C-band slot is located on the left and right side walls of the first through slot, wherein the lateral spacing between the fine capsule-shaped part of the C-band slot and the outer side wall of the rectangular waveguide is w5; the lateral spacing between adjacent C-band slots is q4, The axial spacing is p4, and the axial spacing from the C-band slot closest to the C / X dual-band microwave input end face to the C / X dual-band microwave input end face is s4; the X-band slot is used to radiate X-band microwaves, and the C-band slot is used to radiate C-band microwaves; the Ku-band slot is rectangular, with a total of K3, divided into two columns, with K3 / 2 in number in each column, symmetrically distributed along the central axis OO' in the two second rectangular upper plates on the left and right sides of OO'; the length of the Ku-band slot is L5, the width is w6, and the angle with the BB' axis is θ. On the second rectangular upper plate on the right, the right end of the Ku-band slot closest to O is deflected toward O by θ, and the next Ku-band slot is deflected away from O by θ, on the right The second rectangular upper plate is arranged in a staggered manner; the Ku-band slot 32 is slotted from the upper surface of the second rectangular upper plate to the direction close to the second rectangular bottom plate, with a slot depth of c4, connecting the upper surface of the second rectangular upper plate and the second rectangular channel; the lateral spacing between adjacent Ku-band slots is q5, the axial spacing is p5, and the axial spacing from the Ku-band slot closest to the Ku-band microwave input end face to the Ku-band microwave input end face is s5; the Ku-band slot is used to radiate Ku-band microwaves; two rectangular waveguides are set between the X-band slot and the C-band slot to transmit Ku-band microwaves, and at the same time separate the X-band slot from the C-band slot to form a shoulder arm, and at the same time constitute a choke slot to reduce the mutual influence of C / X bands;

[0016] The metal ridge is a rectangular plate with a width of a5, a height of b5, and a length equal to L0; it is flatly welded on the central axis of the upper surface of the first rectangular bottom plate along the direction of the central axis OO', the connection position between the metal ridge and the first rectangular bottom plate is rounded, and the top of the metal ridge is also rounded, and the chamfer radius is r2; the length of the metal ridge is equal to L0; the width a5 of the metal ridge and the height b5 of the metal ridge will affect the transmission of X-band microwaves, and when the width a5 of the metal ridge is reduced, the transmission of X-band microwaves becomes worse, and when the height b5 of the metal ridge is reduced, the transmission of X-band microwaves becomes worse to cutoff;

[0017] The reflection rod is a metal cuboid rod with a rectangular cross section, a width of w1, a length of L1, and a height equal to the height b2 of the first rectangular middle plate; M reflection rods are welded on the upper surface of the first rectangular bottom plate, connecting the first rectangular bottom plate and the first rectangular upper plate, and attached to the left and right side walls of the first rectangular channel, i.e., the inner surfaces of the two first rectangular middle plates, and are divided into two rows and staggered along the central axis OO' direction. The connection position between the reflection rod and the inner surface of the first rectangular middle plate is rounded, and the chamfer radius is r3. The end of the reflection rod away from the first rectangular middle plate is rounded, and the chamfer radius is equal to r3; the lateral spacing between adjacent reflection rods is q2, and the axial spacing is p2. The axial distance from the reflection rod closest to the C / X dual-band microwave input end face to the C / X dual-band microwave input end face is s2; the reflection rod can offset the equivalent susceptance of the C-band gap, so that the C-band gap is in a resonant state;

[0018] The slotted ridge waveguide wall is welded to the end of the first rectangular channel away from the microwave source, and the end of the first rectangular channel away from the microwave source is closed; the slotted ridge waveguide wall is a metal cuboid, with a width equal to a1, a height equal to b4, and a thickness of s0. A rectangular through groove is dug on the upper surface of the slotted ridge waveguide wall along the direction of the central axis OO', which is the second through groove, with a width of a9 and a depth of b3; the concave waveguide wall is welded to the end of the concave waveguide away from the microwave source, and the ends of the two second rectangular channels away from the microwave source are closed; the concave waveguide wall is a metal cuboid, with a width equal to a9, a height equal to b7, and a thickness equal to s0. A rectangular through groove is dug on the upper surface of the concave waveguide wall along the direction of the central axis OO', which is the third through groove, with a width equal to a3 and a depth equal to c3;

[0019] The electromagnetic bandgap is a cylinder made of a metallic material, with a diameter of d, a height of h, and a rounded top with a chamfer radius equal to r1; N electromagnetic bandgaps are evenly divided into two columns, with the number of each column equal to N / 2. Along the central axis OO’, they are symmetrically distributed on both sides of the first rectangular channel and fixed to the upper surface of the first rectangular base plate with screws; the lateral spacing between the two columns of electromagnetic bandgaps is q1, the axial spacing between adjacent electromagnetic bandgaps in the same column is p1, and the axial spacing from the electromagnetic bandgap closest to the C / X dual-band microwave input end face to the C / X dual-band microwave input end face is equal to s1; the function of the electromagnetic bandgap is to enable the X-band microwave to propagate along the metal ridge between the two columns of electromagnetic bandgaps and around the metal ridge; at the same time, it enables the C-band microwave to transmit through the two columns of electromagnetic bandgaps in the entire slotted ridge waveguide; when the height h of the electromagnetic bandgap decreases, the stopband range moves to lower frequencies, and when the distance q1 between the two columns of electromagnetic bandgaps decreases, the transmission of the X-band microwave deteriorates to cutoff. Adjusting the height h of the electromagnetic bandgap and the distance q1 between the two columns of electromagnetic bandgaps can achieve a change in the stopband range;

[0020] For the sake of convenient description, the conditions satisfied by the structural parameters of the above design are introduced uniformly here:

[0021] 1. The width a1 and height b4 of the slotted ridge waveguide 2 need to satisfy the propagation of the TE 10 mode therein, generally satisfying λ0 / 2 < a1 < λ0, b4 < λ0 / 2, where λ0 is the wavelength in free space. The width a7 of the first rectangular upper plate 213 should be greater than the width a2 of the first rectangular middle plate 212, i.e., a7 > a2; the height b2 of the first rectangular middle plate 212 and the height b3 of the first rectangular upper plate 213 satisfy b1 + b2 + b3 = b4; usually, the height b1 of the first rectangular base plate 211, the height b2 of the first rectangular middle plate 212, and the height b3 of the first rectangular upper plate 213 should be equal, but due to the need to open slots on the rectangular upper plate, its height is slightly reduced, so b1 = b2 > b3 > 0. The length L0 of the slotted ridge waveguide 2 should be related to the number M and position of the reflection rods 23, satisfying L0 = M*p2 + 2*s2.

[0022] 2. The height h of the electromagnetic band gap 1, the width a4 of the first rectangular channel 214, the height b2 of the first rectangular channel 214, the distance q1 between the two rows of electromagnetic band gaps 1, the width a5 of the metal ridge 22, and the height b5 of the metal ridge are designed to enable the X-band microwaves to be confined between the two rows of electromagnetic band gaps 1 and propagate along the metal ridge 22, while enabling the C-band microwaves to be unaffected by the electromagnetic band gap 1 and propagate through the electromagnetic band gap 1 in the entire slotted ridge waveguide 2. First, the electromagnetic simulation software CST Studio Suit is used to simulate the influence of h, a4, b2, q1, a5, and b5 on the dispersion curve of the bandgap range, that is, when h decreases, the bandgap range moves to a lower frequency, when a4 decreases, the C-band microwave transmission deteriorates, when b2 decreases, the bandgap range widens, when q1 decreases, the X-band microwave transmission deteriorates to cutoff, when a5 decreases, the X-band microwave transmission deteriorates, and when b5 decreases, the X-band microwave transmission deteriorates to cutoff. Then, based on the X-band center frequency being within the forbidden band range and the C-band center frequency being outside the forbidden band range, and satisfying a2+a2+a4=a1, and a1>a4>q1>a2>a5, b2>h>b5, the electromagnetic simulation software CST Studio Suit is used to simulate and obtain the precise values ​​of h, a4, b2, q1, a5 and b5; considering the processing cost, the diameter d of the electromagnetic band gap 1 and the axial spacing p1 of the adjacent electromagnetic band gaps 1 on the same side should not be too small. Generally, d>2mm, p1>5mm. The axial spacing s1 from the electromagnetic band gap 1 closest to the input end face to the input end face should satisfy s1=2*p1+1.5*d. According to the axial spacing p1 of the adjacent electromagnetic band gaps 1 on the same side and the axial spacing s1 of the electromagnetic band gap 1 closest to the input end face to the input end face, the number N of the electromagnetic band gaps 1 can be obtained, that is, N=2*(L0-s1*2) / p1.

[0023] 3. The chamfer radius r1 of the top of the electromagnetic band gap 1, the chamfer radius r2 of the metal ridge 22, the chamfer radius r3 of the reflective rod 23, the radius r4 of the X-band gap 215, the chamfer radius R5 of the rectangular part of the C-band gap 216, and the chamfer radius R6 of the fine capsule-shaped part of the C-band gap 216 should all meet the microwave lossless transmission conditions to achieve the purpose of reducing reflection, and R5>r2=r3=r4=R6>r1.

[0024] 4. The width a6 of the rectangular waveguide 31, the width a8 of the second rectangular channel 314, the height b8 of the second rectangular channel 314, the width a3 of the concave waveguide bottom plate 33, the height of the second rectangular bottom plate 311 and the height of the concave waveguide bottom plate 33, the width of the second rectangular middle plate 312 and the height of the second rectangular upper plate 313 are all equal, which are c2; in the design, based on the requirement of enabling the propagation of Ku-band microwaves without affecting the radiation of C-band microwaves and X-band microwaves, and satisfying the condition of c2+c2+a8=a6, the electromagnetic simulation software CST Studio Suit is used to simulate and obtain the precise values ​​of a6, a8, b8, a3, and c2.

[0025] 5. There are K1 X-band slots 215 in total. The normalized equivalent conductance of each X-band slot is Where S 1,1 is the reflection coefficient of the X-band input port obtained by simulating the electromagnetic simulation software CST Studio Suit when the X-band slot 215 is in a resonant state; K1 is the normalized resonant conductance g of the X-band slot 215 X The mathematical relationship between the length L2 of the X-band slot 215 and the X-band slot 215 can be obtained by simulation using the electromagnetic simulation software CST Studio Suit (after the shape of the X-band slot is determined, the normalized resonant conductance g of the X-band slot 215 is X There must be a unique mathematical relationship with the length L2 of the X-band slot 215); K1 X-band slot 215 normalized resonant conductance g X The mathematical relationship between the lateral spacing q3 of adjacent X-band slots 215 can be obtained by simulation using electromagnetic simulation software CST Studio Suit (after the shape of the X-band slot 215 is determined, the normalized resonant conductance g of the X-band slot 215 is X There must be a unique mathematical relationship between the lateral spacing q3 of adjacent X-band slots 215); the axial spacing p3 of adjacent X-band slots 215 should be equal to λ gx / 2, the axial spacing s3 from the X-band slot 215 closest to the C / X dual-band microwave input end face to the input end face should be equal to λ gx ,λ gx is the working wavelength of X-band microwaves; since X-band microwaves are bound between two rows of electromagnetic band gaps 1 and propagate along the metal ridge 22, the X-band slots 215 should be located inside the electromagnetic band gaps 1, that is, the lateral spacing q3 of adjacent X-band slots 215 should be between the width a5 of the metal ridge 22 and the distance q1 between the two rows of electromagnetic band gaps 1, that is, q1>q3>a5 is satisfied. According to the axial spacing p3 of adjacent X-band slots 215 and the axial spacing s3 from the X-band slot 1 closest to the C / X dual-band microwave input end face to the C / X dual-band microwave input end face, the number of electromagnetic band gaps K1 can be obtained, that is, K1=(L0-s3*2) / p3.

[0026] 6. There are K2 C-band slots 216, and the normalized equivalent conductance of each C-band slot where S' 1,1 is the reflection coefficient of the C-band input port simulated by the electromagnetic simulation software CST Studio Suit when the C-band slot 216 is in the resonant state; in order to increase the coupling amount of the C-band slot 216, the C-band slot 216 is designed as a rectangular part and a thin capsule part. The increase in the width w3 and length L3 of the rectangular part of the C-band slot 216 will cause the C-band slot to be in the resonant state. The length L3 of the rectangular part of the C-band slot 216 should be greater than the length L2 of the X-band slot 215, that is, L3 > L2; the normalized resonant conductance g of the thin capsule-shaped part of the K2 C-band slots 216 C The mathematical relationship with the length L4 of the thin capsule-shaped part of the C-band slot 216 can be obtained by simulation with the electromagnetic simulation software CST Studio Suit (after the shape of the C-band slot 216 is determined, there must be a unique corresponding mathematical relationship between the normalized resonant conductance g of the C-band slot 216 C and the length L4 of the C-band slot 216), and L4 < L3; the normalized resonant conductance g of the K2 C-band slots 216 c The mathematical relationship with the lateral spacing q4 between adjacent C-band slots 216 can be obtained by simulation with the electromagnetic simulation software CST Studio Suit (after the shape of the C-band slot 216 is determined, there must be a unique corresponding mathematical relationship between the normalized resonant conductance g of the C-band slot 216 C and the lateral spacing q4 between adjacent C-band slots); the axial spacing p4 between adjacent C-band slots 216 should be equal to λ gc / 2, and the axial spacing s4 from the C-band slot 216 closest to the C / X dual-band microwave input end face to the input end face should be equal to λ gc , λ gcis the operating wavelength of C-band microwaves; the width w4 of the thin capsule-shaped part of the C-band slot 216 is the same as the width w2 of the X-band slot 215, and the width w2 of the thin capsule-shaped part of the C-band slot 216 is smaller than the width w3 of the rectangular part of the C-band slot 216, that is, w4 = w2 < w3; the lateral spacing w5 between the thin capsule-shaped part of the C-band slot 216 and the outer sidewall of the rectangular waveguide 31 should be as small as possible, that is, w5 < w4; the depth of the thin capsule-shaped part of the C-band slot 216 is also the same as the depth of the X-band slot 215, both are c2, then the depth c1 of the rectangular part of the C-band slot 216 should satisfy c1 = b3 - c2; since C-band microwaves can propagate through the electromagnetic bandgap 1 on the rectangular waveguide 31, the C-band slot 216 should be located outside the electromagnetic bandgap 1, that is, the lateral spacing q4 between adjacent C-band slots 216 should be between the distance q1 between two columns of electromagnetic bandgaps 1 and the width a4 of the first rectangular channel 214, that is, a4 > q4 > q1. According to the axial spacing p4 between adjacent C-band slots 216 and the axial spacing s4 from the C-band slot 216 closest to the C / X dual-band microwave input end face to the C / X dual-band microwave input end face, the number K2 of C-band slots 216 can be obtained, that is, K2 = (L0 - s4 * 2) / p4.

[0027] 7. There are K3 Ku-band slots 32 in total, and the normalized equivalent conductance of each Ku-band slot where S” 1,1 is the reflection coefficient of the Ku-band input port simulated by the electromagnetic simulation software CST Studio Suit when the Ku-band slot 32 is in the resonant state; the Ku-band slot 32 is an inclined slot on the narrow side of the rectangular waveguide. Changing the inclination angle θ of the Ku-band slot 32 can change the magnitude of the normalized equivalent conductance. Adjust the depth c4 of the slot cutting into the wide side to make the slot in the resonant state; the mathematical relationship between the normalized resonant conductance g Ku of the K3 Ku-band slots 32 and the inclination angle θ of the Ku-band slot 32 can be simulated by the electromagnetic simulation software CST Studio Suit (after the shape of the Ku-band slot 32 is determined, there must be a unique corresponding mathematical relationship between the normalized resonant conductance g Ku of the Ku-band slot 32 and the inclination angle θ of the Ku-band slot 32); the mathematical relationship between the normalized resonant conductance g Ku of the K3 Ku-band slots 32 and the depth c4 of the Ku-band slot 32 can be simulated by the electromagnetic simulation software CST Studio Suit (after the shape of the Ku-band slot is determined, there must be a unique corresponding mathematical relationship between the normalized resonant conductance g Ku of the Ku-band slot 32 and the depth c4 of the Ku-band slot 32); the normalized resonant conductance g KuThe mathematical relationship of the lateral spacing q5 with the adjacent Ku-band slot 32 can be obtained by simulating with the electromagnetic simulation software CST Studio Suit (after the shape of the Ku-band slot 32 is determined, there must be a unique corresponding mathematical relationship for the normalized resonant conductance g of the Ku-band slot 32). Ku The axial spacing p5 between adjacent Ku-band slots 32 should be equal to λ gKu / 2. The axial spacing s5 from the Ku-band slot 32 closest to the Ku-band microwave input end face to the input end face should be equal to λ gKu , and λ gKu is the operating wavelength of the Ku-band microwave waveguide. Since the Ku-band slot 32 is between the C-band slot 216 and the X-band slot 215, the lateral spacing q5 between adjacent Ku-band slots 32 should be between the lateral spacing q4 of adjacent C-band slots 216 and the lateral spacing q3 of adjacent X-band slots 215, that is, q4 > q5 > q3. According to the axial spacing p5 between adjacent Ku-band slots 32 and the axial spacing s5 from the Ku-band slot 32 closest to the Ku-band microwave input end face to the Ku-band microwave input end face, the number K3 of Ku-band slots 32 can be obtained, that is, K3 = (L0 - s5 * 2) / p5.

[0028] 8. There are M reflection rods 23 in total. In order to cancel the equivalent susceptance of the C-band slot 216 and make it in a resonant state, the reflection rod 23 should be directly opposite to the C-band slot 216, and the number M of the reflection rods 23 and the number K2 of the C-band slots 216 satisfy M = K2 + 1. The higher the height of the reflection rod 23, the better the cancellation effect. However, since the reflection rod 23 is located in the first rectangular channel 214, that is, the height of the reflection rod 23 cannot exceed the height of the first rectangular channel 214, so the height of the reflection rod 23 is also b2. The width w1 and length L1 of the reflection rod 23 have little influence on the cancellation effect. The width w1 of the reflection rod 23 should be between the width w4 of the fine capsule-shaped part of the C-band slot 216 and the width w3 of the rectangular part of the C-band slot 216, that is, w3 > w1 > w4, and the length L1 of the reflection rod 23 and the length L2 of the X-band slot 215 should satisfy L1 < L2. The axial distance p2 between adjacent reflection rods 23 should be equal to λ gc / 2, and λ gc is the operating wavelength of the C-band microwave waveguide. The axial distance p2 between adjacent reflection rods 23 is equal to the axial spacing p4 between adjacent C-band slots 216, that is, p2 = p4. The axial spacing s2 from the reflection rod 23 closest to the C / X dual-band input end face to the C / X dual-band input end face should be equal to λ gc / 4. The axial spacing from the reflection rod 23 closest to the slotted ridge waveguide wall 24 to the slotted ridge waveguide wall 24 is equal to s2.

[0029] 9. Considering the difficulty of processing, the length s0 of the slotted ridge waveguide wall 24 should not be too small. Generally, s0>5mm.

[0030] 10. Since the X-band slot 215 is opened at the bottom of the first through slot 34, the width a3 of the first through slot 34 should be between the width a5 of the metal ridge 22 and the lateral spacing q4 of the adjacent C-band slot 216, that is, q4>a3>a5 is satisfied; the height c2 of the second rectangular bottom plate 311 is consistent with the depth of the fine capsule-shaped part of the C-band slot 216 and the depth of the X-band slot 215, both of which are c2, and c1, c2 and the height b3 of the first rectangular upper plate 213 should satisfy c1+c2=b3; the width of the second through slot 241 is equal to the width of the concave waveguide 3, both of which are a 9, the depth of the second through groove 241 is consistent with the height of the first rectangular upper plate 213, both are b3, the width a9 of the second through groove 241 and the width a8 of the second rectangular channel 314, the width c2 of the second rectangular middle plate 312 and the width a3 of the concave waveguide bottom plate 33 should satisfy a3+a8+a8+c2+c2+c2+c2=a9; the width of the third through groove 351 is consistent with the width of the first through groove 34, both are a3, the depth of the third through groove 351 is consistent with the depth of the first through groove 34, both are c3, and satisfy c3+c2=b3+b6=b7.

[0031] Through the electromagnetic simulation software CST Studio Suit, under the conditions of M=K2+1, L0=M*p2+2*s2, N=(L0-s1*2) / p1, a2+a2+a4=a7+a6+a3+a6+a7=a1, c2+a8+c2+a3+c2+a8+c2=a9, c2+a8+c2=a6, b1+b2+b3=b4, c1+c2=b3, p2=p4=λ gc / 2, p3 = λ gx / 2,,a1>a4>q4>q2>a9>q1>a7>a2>a3>a6>a5>a8>q3>d, b4>b7>c3>b8>b1=b2>b3>b6>h>c1>b5>c2, λ0 / 2 <a1<λ0,b4<λ0 / 2,R5> Under the conditions of r2=r3=r4=R6>r1, L3>L4>L2>L1>L5, w6>w3>w1>w2=w4>w5, d>2mm, p1>5mm, s0>5mm, setting the antenna radiation efficiency greater than 99%, the precise values ​​of parameters M, N, K1, K2, L0, L1, L2, L3, L4, L5, a1, a2, a3, a4, a5, a6, a7, a8, a9, b1, b2, b3, b4, b5, b6, b7, b8, p1, p2, p3, p4, p5, q1, q2, q3, q4, q5, r1, r2, r3, r4, R5, R6, w1, w2, w3, w4, w5, w6 can be obtained.

[0032] The working process of the present invention is as follows: the slotted ridge waveguide 2 binds microwaves of different bands output by a high-power microwave source and whose frequencies are within the forbidden band range around N electromagnetic band gaps 1 and the metal ridge 22; the metal ridge 22 allows microwaves with frequencies within the forbidden band range to propagate along it; and the electromagnetic band gap 1 simultaneously allows microwaves with frequencies outside the forbidden band range to be unconstrained and propagate through the electromagnetic band gap 1. As the height h of the electromagnetic band gap 1 decreases, the bandgap range moves to a lower frequency, the C-band microwave transmission deteriorates when the width a4 of the first rectangular channel 214 decreases, the bandgap range widens when the height b2 of the first rectangular channel 214 decreases, the X-band microwave transmission deteriorates to cutoff when the distance q1 between the two columns of electromagnetic band gaps 1 decreases, the X-band microwave transmission deteriorates when the width a5 of the metal ridge 22 decreases, and the X-band microwave transmission deteriorates to cutoff when the height b5 of the metal ridge 22 decreases, therefore, the bandgap range can be adjusted by changing the height h of the electromagnetic band gap 1, the width a4 of the first rectangular channel 214, the height b2 of the first rectangular channel 214, the distance q1 between the two columns of electromagnetic band gaps 1, the width a5 of the metal ridge 22, and the height b5 of the metal ridge 22. Since the X-band slot 215 is inside the electromagnetic band gap 1 and the C-band slot 216 is outside the electromagnetic band gap 1, the wall current of the X-band is isolated from the C-band slot 216, thereby avoiding the interference of the C-band slot 216 on the transmission and radiation of the X-band microwaves; for the C-band microwaves, the X-band slot 215 has a small offset and a short length, so the X-band slot 215 radiates only a small amount of energy; thus, the transmission and radiation of the C / X-band can be realized without being interfered by the slot of the other band. Two rectangular waveguides 31 are set up between the X-band slot 215 and the C-band slot 216 to transmit Ku-band microwaves, and at the same time, the X-band slot 215 is isolated from the C-band slot 216 to form a shoulder arm and a choke slot, which can also reduce the mutual influence of the C / X-band to a certain extent. Thus, in a single waveguide, X-band microwaves are radiated from the X-band slots, C-band microwaves are radiated from the C-band slots; and Ku-band waveguides are radiated from the Ku-band slots in the concave waveguide 3, thereby achieving radiation of three-band microwaves.

[0033] Compared with the prior art, the present invention can achieve the following technical effects:

[0034] 1. The electromagnetic band gap of the present invention enables the C / X dual-band high-power microwave waveguide slot antenna to have a suitable bandgap range.

[0035] 2. The ridge waveguide width of the present invention is less than one waveguide wavelength, which effectively suppresses the generation of slot array grating lobes.

[0036] 3. The C-band slot and the X-band slot of the present invention are respectively located on the inner and outer sides of the electromagnetic band gap, and a rectangular waveguide is set up between the C-band slot and the X-band slot. While transmitting Ku-band microwaves, the interference between slots of different bands in the same waveguide can be effectively reduced. A single waveguide can realize C / X dual-band radiation, and C / X / Ku triple-band microwave radiation can be realized at the same time.

[0037] 4. The reflective rod of the present invention can offset the equivalent susceptance of the C-band slot, thereby putting the C-band slot in a resonant state.

[0038] 5. The present invention is a metal structure, which can make the three-band antenna take into account the aperture efficiency in the C band, X band and Ku band at the same time, and at the same time overcome the RF breakdown problem that limits the power capacity of the antenna, and realize a dual-band antenna with high power capacity, high aperture efficiency and high radiation efficiency.

[0039] 6. The present invention installs two waveguides on a single waveguide, which has a compact structure and is easy to modularize. BRIEF DESCRIPTION OF THE DRAWINGS

[0040] Figure 1 It is a schematic diagram of the overall structure of the three-band high-power microwave waveguide slit antenna of the present invention;

[0041] Figure 2 It is a partial structural enlarged diagram of the three-band high-power microwave waveguide slit antenna of the present invention; Figure 2 (a) Figure 1 Magnified view of the internal reflective rod at D; Figure 2 (b) Figure 1 A zoomed-in view of the X-band slot, C-band slot, and Ku-band slot at E.

[0042] Figure 3 It is a front view of the C / X dual-band microwave input end face of the triple-band high-power microwave waveguide slot antenna of the present invention.

[0043] Figure 4 It is a front view of the C / X dual-band microwave output end face of the triple-band high-power microwave waveguide slot antenna of the present invention.

[0044] Figure 5 It is a schematic structural diagram of the three-band high-power microwave waveguide slit antenna of the present invention; Figure 5 (a) is a top view of the triple-band high-power microwave waveguide slot antenna of the present invention, Figure 5 (b) Figure 5 (a) Local magnified view at F.

[0045] Figure 6 yes Figure 1 Horizontal section view and partial enlarged view along CC' plane; Figure 6 (a) Yes Figure 1 Horizontal section view along CC' plane; Figure 6 (b) Figure 6 (a) Local magnified view at G.

[0046] Figure 7 It is a two-dimensional radiation pattern of an embodiment of the present invention at an operating frequency of 4.3 GHz.

[0047] Figure 8 It is a two-dimensional radiation pattern of an embodiment of the present invention at an operating frequency of 8.3 GHz.

[0048] Fig. 9 It is a two-dimensional radiation pattern of an embodiment of the present invention at an operating frequency of 12.5 GHz. DETAILED DESCRIPTION

[0049] The specific implementation of the present invention is further described below in conjunction with the drawings and examples.

[0050] Figure 1 Schematic diagram of the overall structure of the three-band high-power microwave waveguide slot antenna of the present invention; Figure 1 As shown, the present invention consists of N electromagnetic band gaps 1 (such as Figure 6 As shown in (a), it is composed of a slotted ridge waveguide 2 and a concave waveguide 3. The end of the slotted ridge waveguide 2 close to the microwave source is defined as the C / X dual-band microwave input end, and the end away from the microwave source is defined as the C / X dual-band microwave output end; the end of the concave waveguide 3 close to the microwave source is defined as the Ku-band microwave input end, and the end away from the microwave source is defined as the Ku-band microwave output end. N electromagnetic band gaps 1 are periodically distributed on both sides of the interior of the slotted ridge waveguide 2 in the order from C / X dual-band microwave input to output; the open end of the slotted ridge waveguide 2 is connected to the microwave source as the input port of the C / X dual-band high-power microwave waveguide slot array antenna, and the other end is a closed structure; the N electromagnetic band gaps 1 are connected and fixed to the slotted ridge waveguide 2 by screws, and N is a positive integer; the open end of the concave waveguide 3 is connected to the microwave source as the input port of the Ku-band high-power microwave waveguide slot array antenna, and the other end is a closed structure;

[0051] Figure 3 It is a front view of the C / X dual-band microwave input end face of the triple-band high-power microwave waveguide slot antenna of the present invention, and it is also a front view of the Ku-band microwave output end face of the triple-band high-power microwave waveguide slot antenna, as shown in FIG. Figure 1 As shown, combined Figure 3 The slotted ridge waveguide 2 is composed of a slotted waveguide 21, a metal ridge 22, M reflection rods 23, and a slotted ridge waveguide wall 24, all of which are made of metal materials; M is a positive integer;

[0052] Figure 4It is a front view of the C / X dual-band microwave output end face of the three-band high-power microwave waveguide slot antenna of the present invention, and it is also a front view of the Ku-band microwave input end face of the three-band high-power microwave waveguide slot antenna. Figure 1 As shown, combined Figure 3 and Figure 4 The concave waveguide 3 is composed of two identical rectangular waveguides 31, a concave waveguide bottom plate 33, and a concave waveguide wall 35, all of which are made of metal materials;

[0053] like Figure 3 As shown, the slotted waveguide 21 consists of a first rectangular bottom plate 211, two first rectangular middle plates 212, and two first rectangular upper plates 213; the central axis OO' of the first rectangular channel 214 is drawn along the C / X dual-band microwave input to output direction, point O is on the C / X dual-band microwave input end surface, and point O' is on the slotted ridge waveguide wall 24; a longitudinal axis AA' is drawn through point O on the C / X dual-band microwave input end surface, AA' is perpendicular to the first rectangular bottom plate 211, the end away from the first rectangular bottom plate 211, i.e., end A, is the upper end, and the end close to the first rectangular bottom plate 211, i.e., end A', is the lower end; a transverse axis BB' is drawn through point O on the C / X dual-band microwave input end surface, the transverse axis BB' is perpendicular to the longitudinal axis AA', end B is the left end, and end B' is the right end; in order to prevent the appearance of grating lobes in the far-field pattern, the width a1 of the slotted waveguide 21 should be less than the free space wavelength;

[0054] like Figure 3 As shown, the first rectangular bottom plate 211 is a rectangular parallelepiped plate with a width equal to a1, a height equal to b1, and a length equal to L0 (see Figure 1 ); the lower surfaces of the two first rectangular middle plates 212 are welded to the left and right ends of the upper surface of the first rectangular bottom plate 211 along the direction of the central axis OO', symmetrically about the central axis OO'; the first rectangular middle plate 212 is a rectangular plate with a width of a2, a height of b2, and a length equal to L0; the lower surfaces of the two first rectangular upper plates 213 are aligned with the end faces of the first rectangular middle plates 212 along the direction of the central axis OO', away from the AA' axis, and are symmetrically welded to the upper surfaces of the two first rectangular middle plates 212; the first rectangular upper plate 213 is a rectangular plate with a width of a7, a height of b3, and a length equal to L0; the surfaces of the first rectangular bottom plate 211, the two first rectangular middle plates 212, and the first rectangular upper plate 213 close to the axis OO' are inner surfaces;

[0055] like Figure 3 As shown, combined Figure 1 and Figure 4The two rectangular waveguides 31 are completely identical, and the two rectangular waveguides 31 are symmetrically attached to the inner surfaces of the two first rectangular upper plates 213 along the central axis OO' direction. The rectangular waveguides 31 can separate the X-band wall current from the C-band gap 216, thereby avoiding the interference of the C-band gap on the X-band microwave transmission and radiation; Figure 4 As shown, the rectangular waveguide 31 is composed of a second rectangular bottom plate 311, two second rectangular middle plates 312, and a second rectangular upper plate 313; the lower surface of the second rectangular bottom plate 311 is aligned with the lower surface of the first rectangular upper plate 213; the second rectangular bottom plate 311, the two second rectangular middle plates 312, and the second rectangular upper plate 313 together form a second rectangular channel 314 (see Figure 4 ), the width of the second rectangular channel 314 is a8, the height is b8, and the length is equal to L0; the concave waveguide bottom plate 33 connects the two second rectangular bottom plates 311 of the two rectangular waveguides 31, and the lower surface of the concave waveguide bottom plate 33 is aligned with the lower surface of the second rectangular bottom plate 311; the first rectangular bottom plate 211, the two first rectangular middle plates 212, the two first rectangular upper plates 213, the two second rectangular bottom plates 311 of the two rectangular waveguides 31 and the concave waveguide bottom plate 33 together form the first rectangular channel 214 (see Figure 1 ), the first rectangular channel 214 has a width of a4, a height of b2, and a length of L0, a4=a1-2*a2;

[0056] like Figure 4 As shown, the second rectangular bottom plate 311 is a rectangular parallelepiped plate with a width of a6, a height of c2, and a length equal to L0 (see Figure 1 ); the lower surfaces of the two second rectangular middle plates 312 are welded to the left and right ends of the upper surface of the second rectangular bottom plate 311 along the direction of the central axis OO'; the second rectangular middle plate 312 is a rectangular parallelepiped plate with a width of c2, a height of b8, and a length equal to L0; the second rectangular upper plate 313 is aligned with the second rectangular middle plate 312 along the direction of the central axis OO', and the end surface away from the AA' axis is welded to the upper surfaces of the two second rectangular middle plates 312; the second rectangular upper plate 313 is a rectangular parallelepiped plate with a width of a6, a height of c2, and a length of L0; the concave waveguide bottom plate 33 and the two second rectangular middle plates 312 on both sides of the central axis OO' form a first through groove 34 (see Figure 1 ), the depth of the first through groove 34 is c1, and the lateral width is a3 (see Figure 3 );

[0057] Figure 5 It is a schematic structural diagram of the three-band high-power microwave waveguide slit antenna of the present invention; Figure 5 (a) is a top view of the triple-band high-power microwave waveguide slot antenna of the present invention, Figure 5 (b) Figure 5 (a) A local magnified view at F. Figure 5 As shown in (a) and 5(b), the concave waveguide bottom plate 33 has an X-band slot 215 along the AA' direction; the first rectangular upper plate 213 has a C-band slot 216 along the AA' direction; the second rectangular upper plate 313 has a Ku-band slot 32 along the AA' direction; the X-band slot 215 is capsule-shaped, with a total of K1, a width of w2, a length of L2, and a depth of c2 (combined with Figure 2 (b) together), both ends are rounded, and the chamfer radius is r4; Figure 5As shown in (a), the X-band slots 215 are opened on the bottom surface of the first through slot 34, divided into two rows, and staggered along the center axis OO' on the left and right sides of OO'. The lateral spacing between adjacent X-band slots 215 is q3, and the axial spacing is p3. The axial spacing between the X-band slot 215 closest to the C / X dual-band microwave input end face and the C / X dual-band microwave input end face is s3; the upper part of the C-band slot 216 is rectangular, and the lower part is a fine capsule shape. There are K2 of them, divided into two rows, and staggered along the center axis OO' in the two first rectangular upper plates 213 on the left and right sides of OO'; the width of the rectangular part of the C-band slot 216 is w3, the length is L3, and the depth is equal to c1. The rectangular part of the C-band slot 216 The two ends of the side wall away from OO' are rounded, and the chamfer radius is R5. The width of the fine capsule-shaped part of the C-band slot 216 is w4, the length is L4, the depth is equal to c2, and the two ends are rounded, and the chamfer radius is equal to R6; the C-band slot 216 is located on the left and right side walls of the first through groove 34, wherein the lateral spacing between the fine capsule-shaped part of the C-band slot 216 and the outer side wall of the rectangular waveguide 31 is w5; the lateral spacing between adjacent C-band slots 216 is q4, and the axial spacing is p4, and the axial spacing between the C-band slot 216 closest to the C / X dual-band microwave input end face and the C / X dual-band microwave input end face is s4; the X-band slot 215 is used to radiate X-band microwaves, and the C-band slot 216 is used to radiate C-band microwaves. The Ku-band slots 32 are rectangular, with a total of K3, divided into two columns, with the number of slots in each column being K3 / 2, and symmetrically distributed in the two second rectangular upper plates 313 on the left and right sides of OO' along the central axis OO' direction; the Ku-band slots 32 are L5 in length, w6 in width, and θ in angle with the BB' axis. On the second rectangular upper plate 313 on the right, the right end of the Ku-band slot 32 closest to O is deflected θ towards O, and the next Ku-band slot 32 is deflected θ away from O, and they are staggered on the second rectangular upper plate 313 on the right; the Ku-band slots 32 are slotted from the upper surface of the second rectangular upper plate 313 toward the direction close to the second rectangular bottom plate 311, and the slots are slotted. The groove depth is c4, connecting the upper surface of the second rectangular upper plate 313 and the second rectangular channel 314; the lateral spacing between adjacent Ku-band slots 32 is q5, the axial spacing is p5, and the axial spacing from the Ku-band slot 215 closest to the Ku-band microwave input end face to the Ku-band microwave input end face is s5; the Ku-band slot 32 is used to radiate Ku-band microwaves; two rectangular waveguides 31 are set up between the X-band slot 215 and the C-band slot 216 to transmit Ku-band microwaves, and at the same time, the X-band slot 215 is separated from the C-band slot 216 to form a shoulder arm, and at the same time, a choke slot is formed, which can also reduce the mutual influence of C / X bands to a certain extent;

[0058] Figure 6 yes Figure 1 Horizontal section view and partial enlarged view along CC' plane; Figure 6 (a) Yes Figure 1 Horizontal section view along CC' plane; Figure 6 (b) Figure 6 (a) A local magnified view at G. Figure 6 As shown in (a), the metal ridge 22 is a rectangular plate with a width of a5 and a height of b5 (see Figure 3 ), with a length equal to L0 (see Figure 1 ); the metal ridge 22 is welded flat on the central axis of the upper surface of the first rectangular bottom plate 211 along the central axis OO' direction, the connection position between the metal ridge 22 and the first rectangular bottom plate 211 is rounded, and the top of the metal ridge 22 is also rounded, and the chamfer radius is r2; the length of the metal ridge 22 is equal to L0; the width a5 of the metal ridge 22 and the height b5 of the metal ridge 22 will affect the transmission of X-band microwaves. When the width a5 of the metal ridge 22 is reduced, the transmission of X-band microwaves becomes worse, and when the height b5 of the metal ridge 22 is reduced, the transmission of X-band microwaves becomes worse to cutoff.

[0059] Figure 2 (a) Figure 1 An enlarged view of the reflective rod 23 at D. Figure 2 (a) and Figure 6 As shown in (b), the reflective rod 23 is a metal rectangular parallelepiped rod with a rectangular cross-section, a width of w1, a length of L1, and a height equal to the height b2 of the first rectangular middle plate 212; M reflective rods 23 are welded on the upper surface of the first rectangular bottom plate 211, connecting the first rectangular bottom plate 211 and the first rectangular upper plate 213, and attached to the left and right side walls of the first rectangular channel 214, i.e., the inner surfaces of the two first rectangular middle plates 212, and are divided into two rows and staggered along the direction of the central axis OO'. The connecting position of the reflective rod 23 and the inner surface of the first rectangular middle plate 212 is chamfered, and the chamfer radius is r3. The end of the reflective rod 23 away from the first rectangular middle plate 212 is chamfered, and the chamfer radius is equal to r3; as shown in FIG. Figure 6 As shown in (b), the lateral spacing between adjacent reflection rods 23 is q2, the axial spacing is p2, and the axial distance between the reflection rod 23 closest to the C / X dual-band microwave input end face and the C / X dual-band microwave input end face is s2. The reflection rod 23 can offset the equivalent susceptance of the C-band slot, thereby putting the C-band slot in a resonant state.

[0060] Figure 4 This is a front view of the C / X dual-band microwave output end face of the triple-band high-power microwave waveguide slot antenna of the present invention. Figure 4 As shown, the slotted ridge waveguide wall 24 is welded to the end of the first rectangular channel 214 away from the microwave source, and the end of the first rectangular channel 214 away from the microwave source is closed; the slotted ridge waveguide wall 24 is a metal cuboid, with a width equal to a1, a height equal to b4, and a thickness of s0 (see Figure 6(a)), a rectangular through groove is dug on the upper surface of the slotted ridge waveguide wall 24 along the central axis OO' direction, which is the second through groove 241, with a width of a9 and a depth of b3;

[0061] like Figure 3 As shown, the concave waveguide wall 35 is welded to the end of the concave waveguide 3 away from the microwave source, closing the ends of the two second rectangular channels 314 away from the microwave source; the concave waveguide wall 35 is a metal cuboid, with a width equal to a9, a height equal to b7, and a thickness equal to s0. A rectangular through groove is dug on the upper surface of the concave waveguide wall 35 along the direction of the central axis OO', which is the third through groove 351 (see Figure 3 ), width equal to a3, depth equal to c3;

[0062] like Figure 3 As shown, the electromagnetic band gap 1 is a cylinder made of metal material, with a diameter of d, a height of h, a rounded corner at the top, and a chamfer radius equal to r1; Figure 6 As shown in (a), N electromagnetic band gaps 1 are evenly divided into two rows, the number of each row is equal to N / 2, and they are symmetrically distributed on the left and right sides of the first rectangular channel 214 along the central axis OO' direction, and are fixed to the upper surface of the first rectangular bottom plate 211 with screws; the lateral spacing between the two rows of electromagnetic band gaps 1 is q1 (see Figure 6 (b)), the axial spacing between adjacent EBGs 1 in the same row is p1 (see Figure 6 (b), the axial spacing between the electromagnetic band gap 1 closest to the C / X dual-band microwave input end face and the C / X dual-band microwave input end face is equal to s1; the function of the electromagnetic band gap 1 is to make the X-band microwave propagate between the two rows of electromagnetic band gaps 1 and around the metal ridge 22, so that the X-band microwave propagates along the metal ridge 22; at the same time, the C-band microwave is transmitted through the two rows of electromagnetic band gaps 1 in the entire slotted ridge waveguide 2; when the height h of the electromagnetic band gap 1 decreases, the bandgap range moves to a lower frequency, and when the distance q1 between the two rows of electromagnetic band gaps 1 decreases, the X-band microwave transmission deteriorates to cutoff, and the bandgap range can be changed by adjusting the height h of the electromagnetic band gap 1 and the distance q1 between the two rows of electromagnetic band gaps 1.

[0063] Example 1

[0064] The specific design dimensions of an embodiment of a three-band high-power microwave waveguide slot antenna for 4.3 GHz, 8.3 GHz, and 12.5 GHz (i.e., the frequencies of the input microwave source are 4.3 GHz, 8.3 GHz, and 12.5 GHz) are given below:

[0065] In order to make 8.3 GHz within the forbidden band and 4.3 GHz outside the forbidden band, it is necessary to adjust the diameter d and height h of the electromagnetic band gap 1 and the width a1 of the slotted ridge waveguide. According to the aforementioned forbidden band requirements, the electromagnetic simulation software CST Studio Suit is used for optimization after preliminary selection to obtain d=3mm, h=8.5mm, a1=61mm, b4=34mm; the width of the first rectangular bottom plate 211 is a1=61mm, the height is b1=12mm, and the length is L0=562.25mm; the width of the first rectangular middle plate 212 is a2=14mm, the height is b2=12mm, and the length is L0=562.25mm; the width of the first rectangular upper plate 213 is a7=18mm, the height is b3=10mm, and the length is L0=562.25mm, and the width of the first through slot 34 is a3=9mm and the depth is c3=17m m, length = L0 = 562.25 mm, width a4 = 33 mm, height b2 = 12 mm, length = L0 = 562.25 mm of the first rectangular channel 214; width a5 = 4.2 mm, height b5 = 7 mm, length = L0 = 562.25 mm of the metal ridge 22; width w1 = 4.2 mm, height b2 = 12 mm, length L1 = 5 mm of the reflective rod 23; the width of the slotted waveguide 21 is limited, and to accommodate the two rectangular waveguides 31 and the X-band slot 215 and the C-band slot 216, the width a6 of the rectangular waveguide 31 is taken into consideration. =8mm, height b7=19mm, length=L0=562.25mm; height c2=2mm, length=L0=562.25mm of the second rectangular bottom plate 311; width c2=2mm, height b8=15mm, length=L0=562.25mm of the second rectangular middle plate 312; width a6=8mm, height c2=2mm, length=L0=562.25mm of the second rectangular upper plate 313; width a8=4mm, height b8=15mm, length=L0=562.25mm of the second rectangular channel 314; concave waveguide The bottom plate 33 has a width a3=9mm, a height c2=2mm, and a length L0=562.25mm; the slotted ridge waveguide wall 24 has a width a1=61mm, a height b4=34mm, and a thickness s0=10mm; the second through slot 241 has a width a9=25mm, a height b7=19mm, and a thickness s0=10mm; the concave waveguide wall 35 has a width a9=25mm, a height b7=19mm, and a thickness s0=10mm; the third through slot 351 has a width a3=9mm, a height c3=17mm, and a thickness s0=10mm.

[0066] The number of electromagnetic band gaps 1 N=136, the lateral spacing q1=19mm between the electromagnetic band gaps 1 on both sides, the longitudinal spacing p1=8mm between adjacent electromagnetic band gaps 1 on the same side, and the longitudinal spacing s1=20.5mm from the electromagnetic band gap 1 closest to the input end to the input end; the number of reflection rods 23 M=12, the lateral spacing q2=28.8mm between adjacent reflection rods 23, the axial spacing p2=43.25mm, and the axial spacing s2=25mm from the reflection rod 23 closest to the input end face to the input end face.

[0067] The number of X-band slots 215 is K1=21, with a width of w2=2mm, a length of L2=16.6mm, and a depth of c2=2mm. The lateral spacing between adjacent capsule-shaped slots is q3=3.2mm, and the longitudinal spacing is p3=23.9mm. The longitudinal spacing from the capsule-shaped slot closest to the C / X-band microwave input terminal to the C / X-band microwave input terminal is s3=58.7mm. The number of C-band slots 216 is K2=11, with a width of w3=6mm, a length of L3=34.3mm, and a depth of c1=8mm for the rectangular part of the C-band slot. The width of w4=2mm, a length of L4=22.3mm, and a depth of c2=2mm for the slender capsule-shaped part of the C-band slot 216. The slender capsule-shaped part of the C-band slot 216 is The lateral spacing w5 of the outer wall of the rectangular waveguide 31 is 1 mm; the lateral spacing q4 of adjacent C-band slots is 31 mm, the axial spacing p4 is 43.25 mm, and the axial spacing s4 from the C-band slot closest to the C / X-band microwave input end face to the input end face is 71.05 mm; the number of Ku-band slots 32 is K3=56, the angle θ with the BB' direction is 20°, the width w6=8.5 mm, the length L5=1.6 mm, the depth c4=3.8 mm, the lateral spacing q5 of adjacent Ku-band slots is 17 mm, the longitudinal spacing p5=20 mm, and the longitudinal spacing s5=21.3 mm from the Ku-band slot closest to the Ku-band microwave input end to the Ku-band microwave input end.

[0068] The chamfer radius r1 of the top of the electromagnetic band gap 1 is 0.5 mm, the chamfer radius r2 of the top of the metal ridge 22 is 1 mm, the chamfer radius r3 of the reflective rod 23 is 1 mm, the chamfer radius r4 of both ends of the capsule-shaped gap is 1 mm, the chamfer radius R5 of the rectangular gap is 2 mm, and the chamfer radius R6 of both ends of the slender capsule-shaped gap is 1 mm.

[0069] According to the above specific parameters, a model was established in the electromagnetic simulation software CST Studio Suit, using C-band microwave, X-band microwave and Ku-band microwave excitation respectively; the C-band frequency was selected as 4.3 GHz, that is, Figure 7 In farfield (f = 4.3), the far field frequency is 4.3 GHz; the selected X-band frequency is 8.3 GHz, that is, Figure 8In farfield (f = 8.3), the far field frequency is 8.3 GHz; the selected Ku band frequency is 12.5 GHz, that is, Fig. 9 Here, farfield (f=12.5) means the far field frequency is 12.5 GHz. Figure 7 is a two-dimensional directional pattern of an embodiment of the present invention at an operating frequency of 4.3 GHz, Figure 7 The vertical axis is the gain of the antenna, the unit is dBi, and the horizontal axis theta is the antenna pitch scanning angle, the unit is degree. Figure 7 As shown, the reflection coefficient at 4.3GHz in the C band is -25.1dB, the gain is 17.9dBi, and the first sidelobe level is -14dB. Figure 8 is a two-dimensional directional pattern of an embodiment of the present invention at an operating frequency of 8.3 GHz, Figure 8 The vertical axis is the gain of the antenna, the unit is dBi, and the horizontal axis theta is the antenna pitch scanning angle, the unit is degree. Figure 8 As shown, the reflection coefficient at 8.3 GHz in the X-band is -20.3 dB, the gain is 21.4 dBi, and the first sidelobe level is -12.7 dB. Fig. 9 is a two-dimensional directional pattern of an embodiment of the present invention at an operating frequency of 12.5 GHz, Fig. 9 The vertical axis is the gain of the antenna, the unit is dBi, and the horizontal axis theta is the antenna pitch scanning angle, the unit is degree. Fig. 9 The reflection coefficient at 12.5GHz in the Ku band is -19.3dB, the gain is 25.9dBi, and the first sidelobe level is -13.0dB. Figure 7 , Figure 8 and Fig. 9 It can be seen that the gain of Example 1 in C-band, X-band and Ku-band is relatively high, and the reflection coefficient and the first sidelobe level are relatively low, thereby achieving the goal of transmitting C-band microwaves, X-band microwaves and Ku waveguide microwaves.

Claims

1. A three-band high-power microwave rectangular waveguide slot antenna, characterized in that The triple-band high-power microwave waveguide slot antenna is composed of N electromagnetic band gaps (1), a slotted ridge waveguide (2) and a concave waveguide (3); the end of the slotted ridge waveguide (2) close to the microwave source is defined as the C / X dual-band microwave input end, and the end away from the microwave source is defined as the C / X dual-band microwave output end; the end of the concave waveguide (3) close to the microwave source is defined as the Ku-band microwave input end, and the end away from the microwave source is defined as the Ku-band microwave output end; the N electromagnetic band gaps (1) are periodically distributed on both sides of the slotted ridge waveguide (2) in the order from C / X dual-band microwave input to output; the open end of the slotted ridge waveguide (2) is connected to the microwave source as the input port of the C / X dual-band microwave, and the other end is a closed structure; the N electromagnetic band gaps (1) are connected and fixed to the slotted ridge waveguide (2) by screws, and N is a positive integer; the open end of the concave waveguide (3) is connected to the microwave source as the input port of the Ku-band microwave, and the other end is a closed structure; The slotted ridge waveguide (2) is composed of a slotted waveguide (21), a metal ridge (22), M reflection rods (23), and a slotted ridge waveguide wall (24), all of which are made of metal materials; M is a positive integer; The concave waveguide (3) is composed of two identical rectangular waveguides (31), a concave waveguide bottom plate (33), and a concave waveguide wall (35), all of which are made of metal materials; The slotted waveguide (21) is composed of three parts: a first rectangular bottom plate (211), two first rectangular middle plates (212), and two first rectangular upper plates (213); a central axis OO' of the first rectangular channel (214) is drawn along the C / X dual-band microwave input to output direction, point O is on the C / X dual-band microwave input end surface, and point O' is on the slotted ridge waveguide wall (24); a longitudinal axis AA' is drawn through point O on the C / X dual-band microwave input end surface, AA' is perpendicular to the first rectangular bottom plate (211), the end away from the first rectangular bottom plate (211), i.e., end A, is the upper end, and the end close to the first rectangular bottom plate (211), i.e., end A', is the lower end; a transverse axis BB' is drawn through point O on the C / X dual-band microwave input end surface, the transverse axis BB' is perpendicular to the longitudinal axis AA', end B is the left end, and end B' is the right end; a width a1 of the slotted waveguide (21) is smaller than the free space wavelength; The first rectangular bottom plate (211) is a rectangular plate with a width equal to a1, a height equal to b1, and a length equal to L0; the lower surfaces of the two first rectangular middle plates (212) are welded symmetrically at the left and right ends of the upper surface of the first rectangular bottom plate (211) along the direction of the central axis OO', about the central axis OO'; the first rectangular middle plate (212) is a rectangular plate with a width of a2, a height of b2, and a length equal to L0; the lower surfaces of the two first rectangular upper plates (213) are aligned with the end faces of the first rectangular middle plates (212) along the direction of the central axis OO', away from the AA' axis, and are symmetrically welded to the upper surfaces of the two first rectangular middle plates (212); the first rectangular upper plate (213) is a rectangular plate with a width of a7, a height of b3, and a length equal to L0; the surfaces of the first rectangular bottom plate (211), the two first rectangular middle plates (212), and the first rectangular upper plate (213) close to the axis OO' are inner surfaces; The two rectangular waveguides (31) are completely identical. The two rectangular waveguides (31) are symmetrically attached to the inner surfaces of the two first rectangular upper plates (213) along the direction of the central axis OO'. The rectangular waveguides (31) separate the wall current of the X-band from the C-band gap (216) to avoid the interference of the C-band gap (216) on the transmission and radiation of X-band microwaves. The rectangular waveguide (31) is composed of a second rectangular bottom plate (311), two second rectangular middle plates (312), and a second rectangular upper plate (313). The lower surface of the second rectangular bottom plate (311) of the rectangular waveguide (31) is aligned with the lower surface of the first rectangular upper plate (213). The second rectangular bottom plate (311), the two second rectangular middle plates (312), and the second rectangular upper plate (313) together surround the The concave waveguide bottom plate (33) connects the two second rectangular bottom plates (311) of the two rectangular waveguides (31), and the lower surface of the concave waveguide bottom plate (33) is aligned with the lower surface of the second rectangular bottom plate (311); the first rectangular bottom plate (211), the two first rectangular middle plates (212), the two first rectangular upper plates (213), the two second rectangular bottom plates (311) of the two rectangular waveguides (31) and the concave waveguide bottom plate (33) together form a first rectangular channel (214), the first rectangular channel (214) has a width of a4, a height of b2, a length of L0, and a4=a1-2*a2; The second rectangular bottom plate (311) is a rectangular plate with a width of a6, a height of c2 and a length of L0; the lower surfaces of the two second rectangular middle plates (312) are welded to the left and right ends of the upper surface of the second rectangular bottom plate (311) along the direction of the central axis OO'; the second rectangular middle plate (312) is a rectangular plate with a width of c2, a height of b8 and a length of L0; the second rectangular upper plate (313) is aligned with the second rectangular middle plate (312) along the direction of the central axis OO', and the end surface away from the AA' axis is welded to the upper surfaces of the two second rectangular middle plates (312); the second rectangular upper plate (313) is a rectangular plate with a width of a6, a height of c2 and a length of L0; the concave waveguide bottom plate (33) and the two second rectangular middle plates (312) on both sides of the central axis OO' form a first through groove (34); the first through groove (34) has a depth of c1 and a lateral width of a3; The concave waveguide bottom plate (33) is provided with an X-band slot (215) along the AA' direction; the first rectangular upper plate (213) is provided with a C-band slot (216) along the AA' direction; the second rectangular upper plate (313) is provided with a Ku-band slot (32) along the AA' direction; the X-band slot (215) is capsule-shaped, with a total of K1, a width of w2, a length of L2, a depth of c2, and rounded corners at both ends, with a chamfer radius of r4; the X-band slots (215) are provided on the bottom surface of the first through groove (34), are divided into two rows, and are staggeredly distributed on the left and right sides of OO' along the central axis OO' direction, the lateral spacing between adjacent X-band slots (215) is q3, the axial spacing is p3, and the distance from the C / X dual-band is 1. The axial spacing between the X-band slot (215) closest to the microwave input end face and the C / X dual-band microwave input end face is s3; the upper part of the C-band slot (216) is rectangular, and the lower part is fine capsule-shaped, with a total of K2, divided into two rows, and staggered along the central axis OO' direction in the two first rectangular upper plates (213) on the left and right sides of OO'; the rectangular part of the C-band slot (216) has a width of w3, a length of L3, and a depth equal to c1; the rectangular part of the C-band slot (216) is rounded at both ends of the side wall away from OO', and the chamfer radius is R5; the fine capsule-shaped part of the C-band slot (216) has a width of w4, a length of L4, and a depth equal to c2, and the two ends are rounded, and the chamfer radius is R5. The diameter is equal to R6; the C-band slot (216) is located on the left and right side walls of the first through slot (34), wherein the transverse spacing between the fine capsule-shaped portion of the C-band slot (216) and the outer side wall of the rectangular waveguide (31) is w5; the transverse spacing between adjacent C-band slots (216) is q4, the axial spacing is p4, and the axial spacing between the C-band slot (216) closest to the C / X dual-band microwave input end face and the C / X dual-band microwave input end face is s4; the X-band slot (215) is used to radiate X-band microwaves, and the C-band slot (216) is used to radiate C-band microwaves; the Ku-band slot (32) is rectangular, with a total of K3, divided into two rows, with the number of slots in each row being K3 / 2, and along the central axis OO ' direction is symmetrically distributed in the two second rectangular upper plates (313) on the left and right sides of OO'; the Ku-band slots (32) have a length of L5, a width of w6, and an angle θ with the BB' axis. On the second rectangular upper plate (313) on the right side, the right end of the Ku-band slot (32) closest to O is deflected by θ towards the O direction, and the next Ku-band slot (32) is deflected by θ away from the O direction, and they are staggered on the second rectangular upper plate (313) on the right side; the Ku-band slots (32) are grooved from the upper surface of the second rectangular upper plate (313) to the direction close to the second rectangular bottom plate (311), the groove depth is c4, and the upper surface of the second rectangular upper plate (313) and the second rectangular channel (314) are connected;The lateral spacing between adjacent Ku-band slots (32) is q5, the axial spacing is p5, and the axial spacing between the Ku-band slot (32) closest to the Ku-band microwave input end face and the Ku-band microwave input end face is s5; the Ku-band slot (32) is used to radiate Ku-band microwaves; two rectangular waveguides (31) are set up between the X-band slot (215) and the C-band slot (216) to transmit Ku-band microwaves, and at the same time, the X-band slot (215) is separated from the C-band slot (216) to form a shoulder arm, and a choke slot is formed to reduce the mutual influence of the C / X bands; The metal ridge (22) is a rectangular plate with a width a5, a height b5, and a length equal to L0; it is welded flat on the central axis of the upper surface of the first rectangular bottom plate (211) along the direction of the central axis OO'; the connection position between the metal ridge (22) and the first rectangular bottom plate (211) is rounded, and the top of the metal ridge (22) is also rounded, and the chamfer radius is r2; the length of the metal ridge (22) is equal to L0; the width a5 of the metal ridge (22) and the height b5 of the metal ridge (22) will affect the transmission of X-band microwaves, and when the width a5 of the metal ridge (22) is reduced, the transmission of X-band microwaves deteriorates, and when the height b5 of the metal ridge (22) is reduced, the transmission of X-band microwaves deteriorates to the point of being cut off; The reflective rod (23) is a metal cuboid rod with a rectangular cross section, a width of w1, a length of L1, and a height equal to the height b2 of the first rectangular middle plate (212); M reflective rods (23) are welded on the upper surface of the first rectangular bottom plate (211), connecting the first rectangular bottom plate (211) and the first rectangular upper plate (213), and attached to the left and right side walls of the first rectangular channel (214), i.e., the inner surfaces of the two first rectangular middle plates (212), and are divided into two rows and staggeredly distributed along the direction of the central axis OO'. The reflective rods (23) and the first rectangular middle plate (212) are connected to each other. The inner surface connection position of a rectangular middle plate (212) is rounded, and the chamfer radius is r3; the end of the reflection rod (23) away from the first rectangular middle plate (212) is rounded, and the chamfer radius is equal to r3; the lateral spacing between adjacent reflection rods (23) is q2, the axial spacing is p2, and the axial distance between the reflection rod (23) closest to the C / X dual-band microwave input end face and the C / X dual-band microwave input end face is s2; the reflection rod (23) offsets the equivalent susceptance of the C-band slot, thereby placing the C-band slot (216) in a resonant state; The slotted ridge waveguide wall (24) is welded to one end of the first rectangular channel (214) away from the microwave source, closing the end of the first rectangular channel (214) away from the microwave source; the slotted ridge waveguide wall (24) is a metal cuboid with a width equal to a1, a height equal to b4, and a thickness of s0. A rectangular through slot, namely the second through slot (241), with a width of a9 and a depth of b3, is dug along the central axis OO’ on the upper surface of the slotted ridge waveguide wall (24); the concave waveguide wall (35) is welded to one end of the concave waveguide (3) away from the microwave source, closing the ends of the two second rectangular channels (314) away from the microwave source; the concave waveguide wall (35) is a metal cuboid with a width equal to a9, a height equal to b7, and a thickness equal to s0. A rectangular through slot, namely the third through slot (351), with a width equal to a3 and a depth equal to c3, is dug along the central axis OO’ on the upper surface of the concave waveguide wall (35). The electromagnetic bandgap (1) is a cylinder made of a metallic material, with a diameter of d, a height of h, and a rounded top with a chamfer radius equal to r1; N electromagnetic bandgaps (1) are evenly divided into two columns, with the number of each column equal to N / 2. Along the central axis OO’, they are symmetrically distributed on both sides of the first rectangular channel (214) and fixed to the upper surface of the first rectangular bottom plate (211) with screws; the lateral spacing between the two columns of electromagnetic bandgaps (1) is q1, the axial spacing between adjacent electromagnetic bandgaps (1) in the same column is p1, and the axial spacing from the electromagnetic bandgap (1) closest to the C / X dual-band microwave input end face to the C / X dual-band microwave input end face is equal to s1; the function of the electromagnetic bandgap (1) is to enable the X-band microwave to propagate along the metal ridge (22) between the two columns of electromagnetic bandgaps (1) and around the metal ridge (22); at the same time, it enables the C-band microwave to transmit through the two columns of electromagnetic bandgaps (1) in the entire slotted ridge waveguide (2); when the height h of the electromagnetic bandgap (1) decreases, the stopband range moves to lower frequencies. When the distance q1 between the two columns of electromagnetic bandgaps (1) decreases, the transmission of the X-band microwave deteriorates to cutoff. By adjusting the height h of the electromagnetic bandgap (1) and the distance q1 between the two columns of electromagnetic bandgaps (1), the change of the stopband range can be realized.

2. The triple-band high-power microwave rectangular waveguide slot antenna as claimed in claim 1, characterized in that The width a1 and height b4 of the slotted ridge waveguide (2) satisfy λ0 / 2 < a1 < λ0, b4 < λ0 / 2, where λ0 is the wavelength in free space; the width a7 of the first rectangular upper plate (213) is greater than the width a2 of the first rectangular middle plate (212); the height b1 of the first rectangular bottom plate (211), the height b2 of the first rectangular middle plate (212), and the height b3 of the first rectangular upper plate (213) satisfy b1 + b2 + b3 = b4, and b1 = b2 > b3 > 0; the length L0 of the slotted ridge waveguide (2) is related to the number M and positions of the reflection rods (23) and satisfies L0 = M*p2 + 2*s2.

3. The triple-band high-power microwave rectangular waveguide slot antenna as claimed in claim 1, characterized in that The height h of the electromagnetic band gap (1), the width a4 of the first rectangular channel (214), the height b2 of the first rectangular channel (214), the distance q1 between the two rows of electromagnetic band gaps (1), the width a5 of the metal ridge (22), and the height b5 of the metal ridge (22) are such that the X-band microwaves are confined between the two rows of electromagnetic band gaps (1) and propagate along the metal ridge (22), while the C-band microwaves are not affected by the electromagnetic band gap (1) and propagate through the electromagnetic band gap (1) in the slotted ridge waveguide (2); the diameter d of the electromagnetic band gap (1) and the distance q1 between the adjacent electromagnetic band gaps (22) on the same side are The axial spacing p1 of the magnetic band gaps (1) satisfies: d>2mm, p1>5mm; the axial spacing s1 from the electromagnetic band gap (1) closest to the C / X dual-band microwave input end face to the C / X dual-band microwave input end face satisfies s1=2*p1+1.5*d, and the number N of the electromagnetic band gaps (1) is obtained according to the axial spacing p1 of adjacent electromagnetic band gaps (1) on the same side and the axial spacing s1 from the electromagnetic band gap (1) closest to the C / X dual-band microwave input end face to the C / X dual-band microwave input end face, that is, N=2*(L0-s1*2) / p1.

4. The triple-band high-power microwave rectangular waveguide slot antenna as claimed in claim 3, characterized in that The determination process of h, a4, b2, q1, a5 and b5 is: first, use the electromagnetic simulation software CST Studio Suit to simulate and obtain the influence of h, a4, b2, q1, a5 and b5 on the dispersion curve of the bandgap range, that is, when h decreases, the bandgap range moves to a lower frequency, when a4 decreases, the C-band microwave transmission deteriorates, when b2 decreases, the bandgap range widens, when q1 decreases, the X-band microwave transmission deteriorates to cutoff, when a5 decreases, the X-band microwave transmission deteriorates, and when b5 decreases, the X-band microwave transmission deteriorates to cutoff; then, based on the X-band center frequency being within the bandgap range and the C-band center frequency being outside the bandgap range, and satisfying a2+a2+a4=a1, and a1>a4>q1>a2>a5, b2>h>b5, use CST Studio Suit to simulate and obtain the precise values ​​of h, a4, b2, q1, a5 and b5.

5. The triple-band high-power microwave rectangular waveguide slot antenna according to claim 1, characterized in that The chamfer radius r1 of the top of the electromagnetic band gap (1), the chamfer radius r2 of the metal ridge (22), the chamfer radius r3 of the reflective rod (23), the radius r4 of the X-band gap (215), the chamfer radius R5 of the rectangular part of the C-band gap (216), and the chamfer radius R6 of the fine capsule-shaped part of the C-band gap (216) meet the microwave lossless transmission conditions, and R5>r2=r3=r4=R6>r1.

6. The triple-band high-power microwave rectangular waveguide slot antenna according to claim 1, characterized in that The width a6 of the rectangular waveguide (31), the width a8 of the second rectangular channel (314), the height b8 of the second rectangular channel (314), the width a3 of the concave waveguide bottom plate (33), the height of the second rectangular bottom plate (311) and the height of the concave waveguide bottom plate (33), the width of the second rectangular middle plate (312) and the height of the second rectangular upper plate (313) are all equal, i.e., c2; based on the condition that the Ku-band microwave propagates without affecting the radiation of the C-band microwave and the X-band microwave and that c2+c2+a8=a6 is satisfied, the precise values ​​of a6, a8, b8, a3 and c2 are obtained by simulation using electromagnetic simulation software CST Studio Suit.

7. The triple-band high-power microwave rectangular waveguide slot antenna as claimed in claim 1, characterized in that The normalized equivalent conductance of the X-band slot (215) Where S 1,1 is the reflection coefficient of the X-band input port obtained by simulating the electromagnetic simulation software CST Studio Suit when the X-band slot (215) is in a resonant state; K1 is the normalized resonant conductance g of the X-band slot (215) X The mathematical relationship between the length L2 of the X-band slot (215) and the length L2 of the X-band slot (215) is obtained by simulation using the electromagnetic simulation software CSTStudio Suit; K1 X-band slot (215) normalized resonant conductance g X The mathematical relationship between the lateral spacing q3 of adjacent X-band slots (215) is obtained by simulation using electromagnetic simulation software CST Studio Suit; the axial spacing p3 of adjacent X-band slots (215) is equal to λ gx / 2, the axial spacing s3 between the X-band slot (215) closest to the C / X dual-band microwave input end face and the C / X dual-band microwave input end face is equal to λ gx ,λ gx is the operating wavelength of X-band microwaves; the lateral spacing q3 of adjacent X-band slots (215) is between the width a5 of the metal ridge (22) and the distance q1 between two rows of electromagnetic band gaps (1), that is, q1>q3>a5 is satisfied; the number K1 of X-band slots (215) = (L0-s3*2) / p3.

8. The triple-band high-power microwave rectangular waveguide slot antenna as claimed in claim 1, characterized in that The normalized equivalent conductance of the C-band slot (216) where S' 1,1 is the reflection coefficient of the C-band input port simulated by the electromagnetic simulation software CST Studio Suit when the C-band slot (216) is in the resonant state; the length L3 of the rectangular part of the C-band slot (216) is greater than the length L2 of the X-band slot (215), i.e., L3 > L2; the mathematical relationship between the normalized resonant conductance g of the thin capsule-shaped part of the K2 C-band slots (216) C and the length L4 of the thin capsule-shaped part of the C-band slot (216) is simulated by the electromagnetic simulation software CST Studio Suit, and L4 < L3; the mathematical relationship between the normalized resonant conductance g of the K2 C-band slots (216) c and the lateral spacing q4 between adjacent C-band slots (216) is simulated by the electromagnetic simulation software CST Studio Suit; the axial spacing p4 between adjacent C-band slots (216) is equal to λ gc / 2, and the axial spacing s4 from the C-band slot (216) closest to the C / X dual-band microwave input end face to the C / X dual-band microwave input end face is equal to λ gc , λ gc is the operating wavelength of the C-band microwave; the width w4 of the thin capsule-shaped part of the C-band slot (216) is the same as the width w2 of the X-band slot (215), and the width w2 of the thin capsule-shaped part of the C-band slot (216) is smaller than the width w3 of the rectangular part of the C-band slot (216), i.e., w4 = w2 < w3; the lateral spacing w5 between the thin capsule-shaped part of the C-band slot (216) and the outer wall of the rectangular waveguide (31) satisfies w5 < w4; the depth of the thin capsule-shaped part of the C-band slot (216) is also the same as the depth of the X-band slot (215), both are c2, and the depth c1 of the rectangular part of the C-band slot (216) satisfies c1 = b3 - c2; the lateral spacing q4 between adjacent C-band slots (216) is between the distance q1 between the two electromagnetic bandgaps (1) and the width a4 of the first rectangular channel (214), i.e., a4 > q4 > q1; the number K2 of C-band slots (216) = (L0 - s4 * 2) / p4.

9. The triple-band high-power microwave rectangular waveguide slot antenna according to claim 1, characterized in that The normalized equivalent conductance of the Ku-band slot (32) is Where S 1,1 is the reflection coefficient of the Ku-band input port obtained by simulating the electromagnetic simulation software CST Studio Suit when the Ku-band slot (32) is in a resonant state; the Ku-band slot (32) is a narrow-side slanted slot of a rectangular waveguide, and K is the normalized resonant conductance g of the three Ku-band slots (32). Ku The mathematical relationship between the tilt angle θ of the Ku-band slot (32) and the K is obtained by simulation using the electromagnetic simulation software CST Studio Suit; K is the normalized resonant conductance g of the three Ku-band slots (32) Ku The mathematical relationship between the depth c4 of the Ku-band slot (32) and K is obtained by simulation using the electromagnetic simulation software CST Studio Suit; the normalized resonant conductance g of the K3 Ku-band slots (32) is Ku The mathematical relationship between the lateral spacing q5 of the adjacent Ku-band slots (32) is obtained by simulation using the electromagnetic simulation software CST Studio Suit; the axial spacing p5 of the adjacent Ku-band slots (32) is equal to λ gKu / 2, the axial spacing s5 between the Ku-band slot (32) closest to the Ku-band microwave input end face and the Ku-band microwave input end face is equal to λ gKu ,λ gKu is the operating wavelength of the Ku-band microwave waveguide; the number of Ku-band slots (32) K3 = (L0-s5*2) / p5.

10. The triple-band high-power microwave rectangular waveguide slot antenna according to claim 1, characterized in that The reflection rod (23) is directly opposite to the C-band slot (216). The number M of the reflection rods (23) satisfies M = K2 + 1. The height of the reflection rod (23) is equal to b2. The width w1 of the reflection rod (23) should be between the width w4 of the thin capsule-shaped part of the C-band slot (216) and the width w3 of the rectangular part of the C-band slot (216), that is, w3 > w1 > w4. The length L1 of the reflection rod (23) and the length L2 of the X-band slot (215) satisfy L1 < L2. The axial distance p2 between adjacent reflection rods (23) is equal to λ gc / 2, where λ gc is the operating wavelength of the C-band microwave waveguide. The axial distance p2 between adjacent reflection rods (23) is equal to the axial pitch p4 between adjacent C-band slots (216), that is, p2 = p4. The axial pitch s2 from the reflection rod (23) closest to the C / X dual-band input end face to the C / X dual-band input end face is equal to λ gc / 4. The axial pitch from the reflection rod (23) closest to the slotted ridge waveguide wall (24) to the slotted ridge waveguide wall (24) is equal to s2.

11. The triple-band high-power microwave rectangular waveguide slot antenna according to claim 1, characterized in that The length s0 of the slotted ridge waveguide wall (24) is greater than 5 mm.

12. The triple-band high-power microwave rectangular waveguide slot antenna according to claim 1, characterized in that The width a3 of the first through groove (34) is between the width a5 of the metal ridge (22) and the lateral spacing q4 of the adjacent C-band slot (216), that is, q4>a3>a5 is satisfied; the height c2 of the second rectangular bottom plate (311) is consistent with the depth of the fine capsule-shaped portion of the C-band slot (216) and the depth of the X-band slot (215), both being c2, and c1, c2 and the height b3 of the first rectangular upper plate (213) satisfy c1+c2=b3; the width of the second through groove (241) is equal to the width of the concave waveguide (3), both being a9, and the depth of the second through groove (241) is equal to the depth of the concave waveguide (3). The height of the third through slot (351) is consistent with the height of the first rectangular upper plate (213), both of which are b3; the width a9 of the second through slot (241) and the width a8 of the second rectangular channel (314), the width c2 of the second rectangular middle plate (312) and the width a3 of the concave waveguide bottom plate (33) satisfy a3+a8+a8+c2+c2+c2+c2=a9; the width of the third through slot (351) is consistent with the width of the first through slot (34), both of which are a3; the depth of the third through slot (351) is consistent with the depth of the first through slot (34), both of which are c3, and satisfy c3+c2=b3+b6=b7.

13. The triple-band high-power microwave rectangular waveguide slot antenna according to claim 1, characterized in that Through the electromagnetic simulation software CST Studio Suit, under the conditions of M=K2+1, L0=M*p2+2*s2, N=(L0-s1*2) / p1, a2+a2+a4=a7+a6+a3+a6+a7=a1, c2+a8+c2+a3+c2+a8+c2=a9, c2+a8+c2=a6, b1+b2+b3=b4, c1+c2=b3, p2=p4=λ gc / 2, p3 = λ gx / 2, a1>a4>q4>q2>a9>q1>a7>a2>a3>a6>a5>a8>q3>d, b4>b7>c3>b8>b1=b2>b3>b6>h>c1>b5>c2, λ0 / 2 <a1<λ0,b4<λ0 / 2,R5> Under the conditions of r2=r3=r4=R6>r1, L3>L4>L2>L1>L5, w6>w3>w1>w2=w4>w5, d>2mm, p1>5mm, s0>5mm, set the antenna radiation efficiency to greater than 99%, and obtain the precise values ​​of parameters M, N, K1, K2, L0, L1, L2, L3, L4, L5, a1, a2, a3, a4, a5, a6, a7, a8, a9, b1, b2, b3, b4, b5, b6, b7, b8, p1, p2, p3, p4, p5, q1, q2, q3, q4, q5, r1, r2, r3, r4, R5, R6, w1, w2, w3, w4, w5, w6, λ0 is the wavelength in free space, λ gc is the operating wavelength of the C-band microwave waveguide, λ gx It is the operating wavelength of X-band microwaves.

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