A method for frequency tuning and mode conversion of relativistic magnetron

Abstract

The present invention provides a relativistic magnetron, comprising a coaxially arranged cathode structure, an anode structure and a resonant cavity, wherein the anode structure comprises an anode circular waveguide, 24 anode fins with an opening angle of 5° uniformly distributed in the circumferential direction, and the anode fins thus form 24 resonant cavities with an opening angle of 10°. The present invention further relates to a tuning and mode conversion method for a 24-cavity relativistic magnetron. The present invention solves the problem that the Cherenkov radiation threshold of the working mode when the relativistic magnetron radiates an output power of 1.0GW is difficult to reduce, and achieves a 10% increase in the power capacity of the working mode under the same volume.

Description

Technical Field

[0001] The invention relates to the field of microwave vacuum electronic devices, and in particular to a method for frequency tuning and mode conversion of a relativistic magnetron. Background Art

[0002] The relativistic magnetron contains multiple cavity structures, and its anode wing structure is arranged in a cylindrical waveguide, with the wings separated by a certain interval, and the middle is evacuated. A cathode structure is placed in the hollow part, and the cathode is, for example, a cathode emitter rod, and each emitter rod is evenly placed in parallel around the circumference, and an external voltage is applied between the anode wing waveguide structure and the transparent cathode emitter column. The relativistic magnetron (RMDO) adopts diffraction output to design the anode cavity structure to achieve the output of working modes of different frequency bands and different powers. Specifically, the working mode is diversified by applying and optimizing the external voltage and applying and optimizing the external magnetic field. At present, the main methods for realizing the mode switching of the relativistic magnetron are to change the external voltage when the external magnetic field is constant or to change the external magnetic field when the external voltage is constant, or to inject a radio frequency signal into the cavity of the relativistic magnetron, so as to achieve the tuning of the working frequency of the relativistic magnetron.

[0003] As a high-power microwave source with great potential for narrowband directed energy weapons, relativistic magnetron has broad application prospects. As early as the Second World War, radar has played an important role. With the development of electronic technology, the role of radar is becoming more and more significant in today's increasingly fierce electronic confrontation. As the core of the radar system, the high-power microwave transmitter is a key factor in improving the performance of the radar system. In addition, the high-power microwave directed energy weapons required to attack electronic equipment require a peak radiation power of GW level. In 2010, M. Liu and Edl Schamiloglu et al. from the United States proposed the use of injected RF radio frequency signals to achieve high-power relativistic magnetron mode switching and frequency tuning (Applied Physics Letters 97(25):251501-251501-3 DOI:10.1063 / 1.3529463). In 2012, Li Wei from the National University of Defense Technology proposed inserting electrolyte materials into the cavity of the relativistic magnetron to achieve tuning of the relativistic magnetron operating frequency (Applied Physics Letters 101(22)DOI:10.1063 / 1.4768691). These methods have made it possible to achieve relativistic magnetron mode switching.

[0004] The bottleneck issues of high-power microwave technology are mainly (1) miniaturization, portability, compactness and low cost of the system; (2) wide-band frequency tuning and mode conversion. As a high-power microwave source with a working mode frequency lower than its cut-off frequency and high power conversion efficiency, the relativistic magnetron can be miniaturized. The axial output structure can reduce the external magnetic field system and make it compact. At present, the research on relativistic magnetrons focuses on how to reduce the Cherenkov radiation threshold of the working mode, improve its power capacity, and wide-band frequency tuning and mode conversion.

[0005] The S-band "crab-style" A6 relativistic magnetron and "crab-style" A12 relativistic magnetron proposed by Liu Meiqin of Xi'an Jiaotong University in China achieve TE11 mode output of 1.0GW by reducing the anode fins of the relativistic magnetron and designing its arrangement in the circular waveguide. The external voltage is reduced from 440kV to 400kV, the external magnetic field is reduced from 0.43T to 0.40T, and the power conversion efficiency can reach 41%.

[0006] Xi'an Jiaotong University in China and the University of New Mexico in the United States jointly proposed using radio frequency signals (RF) to switch between different working modes of the A6 relativistic magnetron. However, the residual energy in the cavity in this mode conversion method will damage the previous microwave source. In 2010, SMA Hashemi of Tusi University of Technology in Tehran, Iran proposed filling 50% of the medium in the A6 magnetron cavity, changing the structure of the A6 relativistic magnetron cavity and thus changing its working mode frequency, thus achieving the A6 relativistic magnetron working frequency tuning and achieving single-mode π operation. However, the medium used in this frequency tuning method is prone to lose its function under the action of 1GW high power, which slows down or makes the frequency tuning speed ineffective. In addition, this study did not involve research on mode conversion.

[0007] In the era of artificial intelligence, in electronic warfare, radar systems require high-power microwave sources as their microwave transmitters to be able to track, identify, detect and evade enemy radar systems, while improving the anti-interference capability of their own radar systems. Therefore, a microwave power source is needed that can improve the power capacity of the working mode without reducing its compactness and portability, and can achieve working mode frequency tuning and mode conversion. Summary of the invention

[0008] To solve the above problems, the present invention proposes an A24 relativistic traveling wave tube, and utilizes the relativistic magnetron cavity anode wing structure design and the arrangement combination of different structures. Under the same external voltage and magnetic field, the arrangement of the anode wing structure of the relativistic magnetron is adjusted to obtain different distributions of electromagnetic dispersion characteristics, and then different working modes are generated under the action of the external voltage and magnetic field, thereby realizing a device for converting different working modes of the relativistic magnetron under the same external voltage and the same external magnetic field.

[0009] According to one aspect of the present invention, there is provided a relativistic magnetron, comprising a coaxially arranged cathode structure, an anode structure and a resonant cavity, wherein the anode structure comprises an anode circular waveguide, 24 circumferentially evenly distributed anode fins with an opening angle of 5°, the anode fins thus forming 24 resonant cavities with an opening angle of 10° each.

[0010] Preferably, at least some of the anode fins are hollow fins with a hollow structure formed in the middle, and the hollow setting is used to introduce negative magnetic permeability.

[0011] Preferably, the anode fins and the hollow fins are arranged at regular intervals.

[0012] Preferably, the anode fin includes an end portion, a constant diameter portion and a transition portion in sequence along the axial direction.

[0013] Preferably, the distance between the outer diameter of the cathode structure and the inner diameter of the anode fin is 1.0 cm to 10.0 cm.

[0014] According to another aspect of the present invention, a method for tuning and mode conversion of a relativistic magnetron as described above is provided, the method comprising maintaining an external voltage applied between a cathode structure and an anode structure unchanged, and achieving operating mode tuning and mode conversion of the 24-cavity relativistic magnetron by changing the strength of an external magnetic field.

[0015] According to another aspect of the present invention, a method for tuning and mode conversion of a relativistic magnetron as described above is provided, the method comprising maintaining the magnetic field strength of the relativistic magnetron unchanged, and achieving operating mode tuning and mode conversion of the 24-cavity relativistic magnetron by changing the external voltage applied between the cathode structure and the anode structure.

[0016] According to another aspect of the present invention, a tuning and mode conversion method of the relativistic magnetron as described above is provided, and the working mode tuning and mode conversion of the 24-cavity relativistic magnetron are achieved by arranging hollow wings at intervals.

[0017] Preferably, the 24-cavity relativistic magnetron realizes the working mode TE 51 TE 31 TE 41 Tuning and mode conversion.

[0018] The present invention proposes to use miniaturized anode fins, and by designing the geometric structure and arrangement combination of the anode fins, to achieve the adjustment and optimization design of the equivalent dielectric parameters in the relativistic magnetron, and finally achieve the phase modulation and mode conversion of the excitation mode in the relativistic magnetron. When the high-energy electrons emitted by the cathode enter the beam-wave interaction region in the relativistic magnetron, the electrons interact with the slow-wave structure of the anode fins. When the anode slow-wave periodic structure changes, the electromagnetic characteristic parameters of the anode structure will change, and the periodic slow-wave structure formed by the anode fins will change the scattering of the high-energy moving electrons generated by the cathode, thereby changing the angular distribution of the working mode in the relativistic magnetron and changing the specific working mode. The new 24-cavity relative magnetron proposed by the present invention can reduce the Cherenkov radiation threshold of the working mode, improve the power capacity of its working mode without reducing its compactness and portability, and can realize its working mode frequency tuning and mode conversion by arranging and combining its anode fin structure, which has important practical value.

[0019] The A24 relativistic magnetron, which can switch modes under transparent cathode drive, has multiple operating modes, and each operating mode has high-power short pulses, and the frequency can be modulated. It serves as a microwave transmitter for radar so that it can avoid detection and tracking by enemy radars, which plays an important role in improving the performance of radar systems.

[0020] The present invention adopts a 5° anode fin structure and constructs a 24-cavity relativistic magnetron through a periodic arrangement, which reduces the Cherenkov threshold of the working mode, that is, when the output power is 1GW, the applied voltage is reduced, the power capacity is increased, and wide-band frequency tuning and mode conversion can be achieved. According to a preferred embodiment of the present invention, the present invention reduces the Cherenkov radiation threshold voltage of the working mode when the output power is 1GW by about 20kV; and when the applied voltage is 400kV, the maximum output power can reach 2.2GW, the power capacity is increased by 10%, and the working mode conversion efficiency can reach a maximum of 70%. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] The specific embodiments of the present invention are further described in detail below in conjunction with the accompanying drawings:

[0022] Figure 1 An axial schematic diagram of a relativistic magnetron according to an embodiment of the present invention is shown;

[0023] Figure 2 A schematic cross-sectional view of a relativistic magnetron anode structure according to an embodiment of the present invention is shown;

[0024] Figure 3 A schematic diagram of the wing structure of the first embodiment of the present invention is shown;

[0025] Figure 4400 kV output characteristic curve of the relativistic magnetron of the first example of the present invention is shown;

[0026] Figure 5 360 kV output characteristic curve of the relativistic magnetron of the first example of the present invention is shown;

[0027] Figure 6 A schematic diagram showing the structure of a wing according to a second embodiment of the present invention is shown;

[0028] Figure 7 The equivalent dielectric constant and magnetic permeability of the fin structure of the second example of the present invention are shown;

[0029] Figure 8 A schematic diagram showing the structure of a wing according to a third embodiment of the present invention is shown;

[0030] Fig. 9 The equivalent dielectric constant and magnetic permeability of the fin structure of the third embodiment of the present invention are shown;

[0031] Fig.10 A schematic diagram of the wing structure of a fourth example of the present invention is shown;

[0032] Fig.11 The equivalent dielectric constant and magnetic permeability of the fin structure of the fourth example of the present invention are shown;

[0033] Fig.12 A schematic diagram showing the structure of a wing according to a fifth embodiment of the present invention is shown;

[0034] Fig.13 The equivalent dielectric constant and magnetic permeability of the fin structure of the fifth embodiment of the present invention are shown;

[0035] Fig.14 A schematic diagram showing the structure of a wing according to a sixth embodiment of the present invention is shown;

[0036] Fig.15 The equivalent dielectric constant and magnetic permeability of the fin structure of the sixth example of the present invention are shown;

[0037] Fig.16 A schematic cross-sectional view of a relativistic magnetron according to a seventh embodiment of the present invention is shown;

[0038] Fig.17 The eigenfrequency curve of the relativistic magnetron of the seventh embodiment of the present invention is shown;

[0039] Fig.18 A diagram showing the working mode of a relativistic magnetron according to a first embodiment of the present invention;

[0040] Fig.19 A working mode diagram of a relativistic magnetron according to a seventh embodiment of the present invention is shown;

[0041] Fig. 20A schematic cross-sectional view of a relativistic magnetron according to an eighth embodiment of the present invention is shown;

[0042] Fig.21 The 400 kV output characteristic curve of the relativistic magnetron of the eighth example of the present invention is shown;

[0043] Fig. 22 A schematic cross-sectional view of a relativistic magnetron according to a ninth embodiment of the present invention is shown;

[0044] Fig.23 The 400 kV output characteristic curve of the relativistic magnetron of the ninth example of the present invention is shown. DETAILED DESCRIPTION

[0045] In order to more clearly illustrate the present invention, the present invention is further described below in conjunction with preferred embodiments and accompanying drawings. Similar components in the accompanying drawings are represented by the same reference numerals. It should be understood by those skilled in the art that the content specifically described below is illustrative rather than restrictive, and should not be used to limit the scope of protection of the present invention.

[0046] The relativistic magnetron contains multiple cavity structures, and its anode fin structure is arranged in a cylindrical waveguide, and the fins are separated by a certain interval, and the middle is evacuated. The cathode structure is placed in the hollow part. The cathode adopts a cylindrical support plate on which a cathode emitter rod is installed. Each emitter rod is evenly placed in parallel around the circumference, and an external voltage is applied between the anode fin waveguide structure and the transparent cathode emitter column. The output structure can include a waveguide and a horn antenna, for example, at an angle of 17.5° to the longitudinal axis.

[0047] The present invention proposes to use miniaturized anode fins, and to achieve adjustment and optimization design of equivalent dielectric parameters in a relativistic magnetron by designing the geometric structure and arrangement combination of the anode fins, and finally to achieve phase modulation and mode conversion of the excitation mode in the relativistic magnetron. When high-energy electrons emitted by the cathode enter the beam-wave interaction region in the relativistic magnetron, the electrons interact with the slow-wave structure of the anode fins. When the anode slow-wave periodic structure changes, the electromagnetic characteristic parameters of the anode structure will change, and the periodic slow-wave structure formed by the anode fins will change the scattering of high-energy moving electrons generated by the cathode, thereby changing the angular distribution of the working mode in the relativistic magnetron and changing the specific working mode.

[0048] Figures 1 to 3A relativistic magnetron according to a specific embodiment of the present invention is shown, and the relativistic magnetron includes a coaxially arranged cathode structure 230, an anode structure and a resonant cavity, and the anode structure includes an anode shell, also known as an anode circular waveguide 220, and 24 anode fins 210. Each fin has a fan-shaped structure with an opening angle θ2 of 5°, radially extending from the anode shell to the cathode side, and uniformly arranged along the circumference, thereby forming 24 resonant cavities with opening angles θ1 of 10°. The anode fins include an end, an equal diameter portion, and a transition portion linearly transitioning from the equal diameter portion to the anode shell from the input port side of the magnetron to the output port side. The equal diameter portion of the fin forms the inner diameter Rvane of the anode structure, and the anode shell forms the resonant cavity radius Rcav, which constitutes a beam-wave interaction region in the relativistic magnetron, also known as a slow wave structure.

[0049] One embodiment of the present invention proposes a 24-cavity relativistic magnetron A24, which can achieve phase modulation and mode conversion of the excitation mode in the relativistic magnetron by designing the geometric structure and arrangement combination of the anode fins, adjusting and optimizing the equivalent dielectric parameters in the relativistic magnetron. When the high-energy electrons emitted by the cathode enter the beam-wave interaction region in the relativistic magnetron, the electrons interact with the slow-wave structure of the anode fins. When the anode slow-wave periodic structure changes, the electromagnetic characteristic parameters of the anode structure will change, and the periodic slow-wave structure formed by the anode fins will change the scattering of the high-energy moving electrons generated by the cathode, thereby changing the angular distribution of the working mode in the relativistic magnetron and changing the specific working mode.

[0050] In another embodiment of the present invention, the anode fins of the present invention may have different hollow geometric structures to introduce negative magnetic permeability. When the 5° anode fins are replaced by 5° hollow structure fins at regular intervals, the operating mode and spectrum distribution will change, achieving operating mode frequency tuning and conversion.

[0051] The present invention will be specifically described below with reference to examples.

[0052] In each embodiment of the present invention, the anode is subjected to a gas release treatment, and the cathode structure is composed of a cathode tray and a cathode emitter. The longitudinal length of the cathode emitter is about 13.5 cm, the cathode material can be tungsten, brass, etc., and the inner diameter of the anode structure Rvane = 1.0 cm to 10.0 cm.

[0053] First Example

[0054] Figure 3The fin structure of the first example of the present invention is shown, in which the cavity opening angle θ1=10°, the anode fin opening angle θ2=5°, and the fin structure includes an end portion, an equal diameter portion, and a transition portion from the equal diameter portion to anode housing. The inner diameter of the 24-cavity relativistic magnetron anode structure formed by the fin structure is Rvane=2.11 cm, and the resonance cavity radius Rcav=4.11 cm.

[0055] Figure 4 The output characteristic curve of the relativistic magnetron of the first example is shown when the applied voltage U=400kV and the applied magnetic field range is 0.29T~0.43T. The relationship between the output power and the power conversion efficiency changes with the applied voltage and the magnetic field. It can be seen that when the applied voltage is constant, the working mode of the relativistic magnetron changes with the change of the applied magnetic field. 51 TE 31 TE 41 , the electronic efficiency can reach up to about 60%. Figure 5 The output characteristic curve of the relativistic magnetron according to the first example is shown when the applied voltage U=360kV and the magnetic field is 0.29T~0.43T, and the relationship between the output power and the power conversion efficiency with the applied voltage and the magnetic field. The figure also shows the working mode TE 31 TE 41 When the applied voltage is constant, the electronic efficiency can reach up to about 70% as the applied magnetic field changes.

[0056] Combination Figure 4 and Figure 5 It can be seen that according to the relativistic magnetron with 24 resonant cavity structure of the present invention, the same relativistic magnetron, under the same magnetic field, when the voltage changes, can achieve working mode frequency tuning and mode conversion; under the same applied voltage, when the magnetic field changes, it can achieve working mode frequency tuning and mode conversion. The A24 relativistic magnetron proposed by the present invention has flexible tuning ability and mode conversion ability, and has the characteristics of stable electronic working mode and high output power conversion efficiency.

[0057] Preferably, the present invention uses a compact output, and the energy of the output mode is output through 24 cavity output energies with an opening angle of 10° connected to the horn antenna output.

[0058] Second Example

[0059] The magnetron oscillator is an orthogonal field device that generates an orthogonal DC electric field and magnetic field (E dc ×B z) under the action of the cathode, the high-energy electrons emitted by the cathode move angularly along the anode slow-wave structure. The anode fins of the non-hollowed 5° metamaterial unit structure are similar to a rod with negative conductivity inserted into a circular waveguide, while the hollowed irregular ring 5° metamaterial unit structure is similar to an open ring with negative magnetic permeability placed in a circular waveguide. Their different arrangements and combinations can adjust the effective dielectric constant and magnetic permeability of the medium of the 24-cavity relativistic magnetron, thereby regulating the electromagnetic wave to release energy into the circular waveguide in a controllable manner.

[0060] Figure 6 FIG. 2 shows a schematic diagram of the anode fin structure according to a second example of the present invention. Figure 3 The fin structure of this example is provided with an irregular hollow structure in the equal diameter part and the transition part, so as to obtain an irregular ring structure fin. The hollow structure is rectangular in the equal diameter part of the fin, and increases from the cathode layer to the anode shell side and from the input side to the output side in the fin transition part, so as to reduce the reflection of the output port of the anode fin. Figure 7 Show Figure 6 The equivalent dielectric constant and magnetic permeability of the wing structure shown in FIG. 1 , the wing structure has a negative dielectric constant and a relatively large negative magnetic permeability at a frequency of 2.37-2.56 GHz.

[0061] Third Example

[0062] Figure 8 FIG. 1 is a schematic diagram of the structure of an anode fin according to a third example of the present invention. This example provides a hollow fin having the same outer dimensions as the anode fin of the first example. Figure 3 The fin shown in this example has a rectangular hollow structure on the cathode side of the equal diameter portion, which is used to reduce reflection at the output port of the anode fin. Fig. 9 Show Figure 8 The equivalent dielectric constant and magnetic permeability of the fin structure shown have different dielectric constant and magnetic permeability from those of the fin structure of the second example in the frequency range of 2.0-2.8 GHz.

[0063] Fourth Example

[0064] Fig.10 FIG. 1 is a schematic diagram of the structure of an anode fin according to a fourth example of the present invention. This example provides a hollow fin having the same outer dimensions as the anode fin of the first example. Figure 3 The fin shown in this example has a triangular hollow structure at the transition portion, and the shape of the hollow structure corresponds to the shape of the transition portion, which is used to reduce the reflection of the output port of the anode fin. Fig.11 Show Fig.10The equivalent dielectric constant and magnetic permeability of the wing structure shown in the figure have a dielectric constant and magnetic permeability variation law similar to that of the wing structure of the third example in the frequency range of 2.0-2.8 GHz.

[0065] Fifth Example

[0066] Fig.12 FIG. 5 is a schematic diagram of the structure of an anode fin according to a fifth example of the present invention. This example provides a hollow fin having the same outer dimensions as the anode fin of the first example. Fig.10 The fin shown in this example has a circular hollow structure at the transition portion, which is used to reduce the reflection of the output port of the anode fin. Fig.13 Show Fig.12 The equivalent dielectric constant and magnetic permeability of the fin structure shown in the figure have dielectric constant and magnetic permeability variation rules that are not used for the fin structures of other examples in the frequency range of 2.0-2.8 GHz.

[0067] Sixth Example

[0068] Fig.14 FIG. 6 is a schematic diagram of the structure of an anode fin according to a sixth example of the present invention. This example provides a hollow fin having the same outer dimensions as the anode fin of the first example. Fig.10 The fin shown in this example has a square hollow structure at the transition portion to reduce reflection at the output port of the anode fin. Fig.15 Show Fig.14 The equivalent dielectric constant and magnetic permeability of the fin structure shown in the figure have dielectric constant and magnetic permeability variation rules that are not used for the fin structures of other examples in the frequency range of 2.0-2.8 GHz.

[0069] It can be seen from the above different examples that by introducing hollows of different shapes into the wing structure, the wing can have different negative magnetic permeabilities, different laws of change of negative magnetic permeabilities with frequency, and different laws of change of dielectric constants with frequency.

[0070] Seventh Example

[0071] Fig.16A schematic cross-sectional view of a relativistic magnetron of the seventh example of the present invention is shown. The relativistic magnetron includes a coaxially arranged cathode structure 260, an anode structure and a resonant cavity, and the anode structure includes an anode shell also called an anode circular waveguide 250, an anode wing and a hollow wing. Different from the first example, the A24 relativistic magnetron of the seventh example has 6 wing structures 240 of the second example inserted between 18 wing structures of the first example, forming a 24-cavity relativistic magnetron. Among them, 6 irregular ring structure wings with irregular hollowing are arranged at intervals of 60 degrees, replacing the wing structures of the first example at the corresponding positions. The ring structure wing with irregular hollowing has negative magnetic permeability. Every three conventional first example wings are used in combination with one irregular ring structure wing. Compared with the A24 relativistic magnetron of the first example, the operating frequency of the eigenmode of the A24 relativistic magnetron is reduced, see Fig.17 ; At the same time, under the same external voltage and external magnetic field, the working mode changes. Specifically, Fig.18 As shown, the A24 relativistic magnetron of the first example of the present invention works in the TE mode when the applied voltage is U=400kV and the magnetic field is B=0.36T. 41 ,like Fig.19 As shown, the working mode of the A24 relativistic magnetron of the seventh example is TE when the applied voltage is U=400kV and the magnetic field is B=0.36T. 31 It can be seen that the use of 5° hollow fins to replace conventional 5° anode fins can achieve working mode frequency tuning and mode conversion under the same external voltage and external magnetic field; the electronic working mode of the A24 relativistic magnetron mode conversion device of the present invention is stable and the output power conversion efficiency is high; the hollow fins with irregular open rings have a simple manufacturing process and can achieve high-power mode conversion.

[0072] Eighth Example

[0073] Fig. 20A schematic cross-sectional view of a relativistic magnetron of the eighth example of the present invention is shown. The relativistic magnetron includes a coaxially arranged cathode structure 260, an anode structure and a resonant cavity, and the anode structure includes an anode shell also called an anode circular waveguide 250, an anode wing and a hollow wing. Different from the first example, the A24 relativistic magnetron of the eighth example has 8 wing structures 240 of the second example inserted between 16 wing structures of the first example, forming a 24-cavity relativistic magnetron. Among them, 8 irregular ring structure wings with irregular hollowing are arranged at intervals of 45 degrees, replacing the wing structures of the first example at the corresponding positions. The ring structure wing with irregular hollowing has negative magnetic permeability, and every two conventional first example wings are used in combination with an irregular ring structure wing. Compared with the first example A24 relativistic magnetron, under the same external voltage and magnetic field, the relativistic magnetron of the eighth example has different output power, efficiency, efficiency and spectrum relationship. Specifically, as Figure 4 As shown, the relativistic magnetron of the first example has three working modes TE when the applied voltage U=360kV and the magnetic field is 0.29T~0.43T. 51 TE 41 TE 31 Changes between Fig.21 As shown, the relativistic magnetron of the eighth example has two working modes TE when the applied voltage U=360kV and the magnetic field 0.29T~0.43T. 41 TE 31 The maximum electronic efficiency can reach about 65%. It can be seen that the A24 relativistic magnetron obtained by combining different structures of wings with different dielectric constants and permeabilities can achieve different working modes under the same external voltage and magnetic field conditions.

[0074] Ninth Example

[0075] Fig. 22A schematic cross-sectional view of a relativistic magnetron of the ninth example of the present invention is shown. The relativistic magnetron includes a coaxially arranged cathode structure 290, an anode structure and a resonant cavity, the anode structure including an anode shell also called an anode circular waveguide 280, an anode wing and a hollow wing. Different from the first example, the A24 relativistic magnetron of the eighth example has 12 wing structures 270 of the second example inserted between the 12 wing structures of the first example, forming a 24-cavity relativistic magnetron. Among them, 12 irregular ring structure wings with irregular hollowing are arranged at intervals of 30 degrees, replacing the wing structures of the first example at the corresponding positions. The ring structure wing with irregular hollowing has negative magnetic permeability, and each conventional first example wing is used in combination with an irregular ring structure wing. Compared with the first example A24 relativistic magnetron, under the same external voltage and magnetic field, the relativistic magnetron of the ninth example has different output power, efficiency, efficiency and spectrum relationships. Specifically, as Figure 4 As shown, the relativistic magnetron of the first example has three working modes TE when the applied voltage U=360kV and the magnetic field is 0.29T~0.43T. 51 TE 41 TE 31 Changes between Fig.23 As shown, the relativistic magnetron of the ninth example has three working modes TE when the applied voltage U=360kV and the magnetic field is 0.29T~0.43T. 51 TE 41 TE 31 The relationship between the change of the magnetic field strength and the change of the A24 relativistic magnetron is different from that of the first example, and the maximum electronic efficiency can reach more than 50%. It can be seen that the A24 relativistic magnetron obtained by combining different structural wings with different dielectric constants and magnetic permeabilities can achieve different working modes under the same external voltage and magnetic field conditions.

[0076] The present invention introduces the method of regulating electromagnetic waves by fins into the design of a high-power microwave source relativistic magnetron, designs 5° fan-shaped anode fins with a size smaller than the working wavelength, and integrates the arrangement sequence in the relativistic magnetron, and converts DC energy into RF wave energy output by interacting with high-energy electron beams, thereby reducing the Cherenkov radiation threshold of 20kV when the working mode outputs 1GW energy, achieving a maximum output power of 2.2GW at an applied voltage of 400kV, and increasing the power capacity by 10%. The power conversion efficiency of the working mode can reach 70%.

[0077] In summary, the present invention provides an A24 relativistic magnetron having an anode wing with an opening angle of 5° and 24 resonant cavities with an opening angle of 10°, and further provides a tuning and mode conversion method for the A24 relativistic magnetron. The tuning and mode conversion of the magnetron can be achieved by adjusting the external voltage or magnetic field of the magnetron; or the magnetic field strength of the magnetron remains unchanged, and the working mode tuning and mode conversion of the magnetron are achieved by changing the external voltage applied between the cathode structure and the anode structure; the working mode tuning and mode conversion of the magnetron can be achieved by arranging wings with hollow structures at intervals and changing the arrangement of wings with different structures.

[0078] Obviously, the above embodiments of the present invention are merely examples for clearly illustrating the present invention, and are not limitations on the implementation methods of the present invention. For ordinary technicians in the relevant field, other different forms of changes or modifications can be made based on the above description. It is impossible to list all the implementation methods here. All obvious changes or modifications derived from the technical solution of the present invention are still within the protection scope of the present invention.

Claims

1. A relativistic magnetron, comprising a cathode structure, an anode structure and a resonant cavity arranged coaxially, characterized in that: The anode structure comprises an anode circular waveguide, 24 anode fins uniformly distributed in the circumferential direction with an opening angle of 5°, and 24 resonant cavities each with an opening angle of 10° formed thereby; At least some of the anode fins are hollow fins with a hollow structure formed in the middle, and the hollow setting is used to introduce negative magnetic permeability; The anode fins and the hollow fins are arranged at regular intervals.

2. The relativistic magnetron according to claim 1, characterized in that: The hollow fins are arranged at intervals of 30°, 45°, or 60°.

3. The relativistic magnetron according to claim 1, characterized in that: The anode fin includes an end portion, a constant diameter portion and a transition portion in sequence along the axial direction.

4. The relativistic magnetron according to claim 1, characterized in that: The distance between the outer diameter of the cathode structure and the inner diameter of the anode fin is 1.0 cm to 10.0 cm.

5. A relativistic magnetron tuning and mode conversion method according to claim 1, characterized in that: The method comprises the steps of maintaining an external voltage applied between a cathode structure and an anode structure unchanged, and realizing working mode tuning and mode conversion of a 24-cavity relativistic magnetron by changing the strength of an external magnetic field.

6. A relativistic magnetron tuning and mode conversion method according to claim 1, characterized in that: The method comprises the following steps: keeping the magnetic field strength of the relativistic magnetron unchanged, and realizing the working mode tuning and mode conversion of the 24-cavity relativistic magnetron by changing the external voltage applied between the cathode structure and the anode structure.

7. A relativistic magnetron tuning and mode conversion method according to claim 1, characterized in that: The working mode tuning and mode conversion of the 24-cavity relativistic magnetron are achieved by arranging hollow wings at intervals.

8. A method for tuning and mode conversion of a relativistic magnetron according to any one of claims 5 to 7, characterized in that: The 24-cavity relativistic magnetron realizes the TE working mode 51 TE 31 TE 41 Tuning and mode conversion.

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