Design of permanent magnet packaging for an S-band relativistic magnetron with TE11 mode output
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摘要: 对一个S波段TE11输出8腔全腔提取相对论磁控管(R8 ACAE-RM)的永磁包装设计进行了初步探索。采用一种内磁块和外磁块相组合的结构,内磁块置于阳极筒内阳极块两端,外磁块置于阳极筒外,在互作用区产生磁感应强度约为0.34 T,轴向均匀区长度为72 mm的磁场,永磁体重量仅为21 kg。相较于传统外磁体系统,该设计可以使磁体重量降低,互作用区磁场强度更加均匀,系统结构更加紧凑,满足高功率微波源系统的轻量化、小型化需求。相对论磁控管选择
$ \mathit{\pi } $ 模作为其工作模式,通过全腔提取结构输出4个90°扇形TE11模式,最后通过同轴插板模式转换器进行模式转换输出圆波导TE11模式。利用粒子模拟软件对器件仿真模拟,在二极管电压320 kV,永磁体产生的磁场空间下,R8 ACAE-RM获得了1.06 GW的微波输出功率,微波中心频率为2.44 GHz,转换效率约为47%。Abstract: The design of permanent magnet packaging for a compact S-band 8-cavity all-cavity axial extraction relativistic magnetron (R8 ACAE-RM) with an output mode of TE11 is preliminarily explored. The inner magnetic block is placed at both ends of the anode block in the anode cylinder, and the outer magnetic block is placed outside the RM, which generates a magnetic field of about 0.34 T and a length of 72 mm on the axial uniform zone in the interaction zone, and the weight of the permanent magnet is only 21 kg. Compared with the traditional external magnet system, this design can reduce the weight of the magnet, the magnetic field strength in the interaction zone is more uniform, and the system structure is more compact, which can meet the lightweight and miniaturization requirements of high-power microwave source systems. The device applies π mode as its operating mode, four 90° sector TE11 modes are extracted through all-cavity axial extraction structure, and a coaxial-plate-inserted mode converter is designed for mode conversion, thus to obtain TE11 mode in circular waveguide. In particle-in-cell (PIC) simulation, the proposed R8 ACAE-RM can generate a microwave power of 1.06 GW with a pure TE11 mode at the frequency of 2.44 GHz under the conditions of a guiding magnetic generated by the inner and outer magnetic blocks, a diode voltage of 320 kV, and power conversion efficiency of 47%.-
Key words:
- high power microwave /
- permanent magnet packaging /
- TE11 mode /
- relativistic magnetron /
- mode conversion
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表 1 R8 ACAE-RM结构参数
Table 1. Parameters of simulated R8 ACAE-RM
length of anode
block, L/mmouter radius of
cathode, Roc/mminner radius of
cathode, Ric/mmlength of cathode
emitter, Le/mmanode radius,
RA/mmcavity radius,
RCv/mmrectangular vane
width, w/mmopen angle of
coupling slot, θ/(°)72 11 10 72 22 38 10 17 表 2 同轴插板模式转换器的结构参数
Table 2. Parameters of the coaxial-plate-inserted mode converter
length of short
board, L1/mmlength of long
board, L2/mmlength of symmetrical
board, L3/mmlength of
cone, LC/mmcone radius,
RC/mmcircular waveguide
radius, RO/mmlength of step
board, LS/mm136 277 299 99 21 62 80 -
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