电子回旋共振（ECR）磁喷管推进器是一种利用电磁波与磁场产生等离子喷流的推进装置。由于射频物理的限制，等离子推进器核心部件—离子源的尺寸与效率难以突破。为此，本文开发了一种结构紧凑的同轴微波六极柱ECR离子源，并将其应用于同轴微波ECR磁喷管推进器。ECR是一种电子与电场在频率与相位耦合时加速电子、并供给电子动能的一种现象，最终高速电子与离子被磁喷管所加速脱离推进器形成等离子喷流，该过程不需要额外的加速电极，使得整体结构非常简洁。 与传统的使用单一永磁体建构2维ECR共振面的ECR推进器不同，本文使用两个环形永磁体，通过磁场交联的方式形成磁镜，大大延拓了ECR共振面在放电室内的覆盖面积，获得了一个轴向覆盖率约为100 %，径向覆盖率约为94 %的3维ECR共振面的主结构场，从而大幅度增加了电子吸收电磁波的有效区域。因此，通过放电室的气体分子有更高的几率被高能电子轰击，从而实现推进剂更高的电离效率。 在ECR主结构场的基础上加入六极柱磁场，解决了轴向磁镜对于径向运动电子约束能力不足的问题。六极柱磁场进一步约束放电室中的电子，既提升了电子的停留时间，同时又减少电子轰击壁面的现象。此外，六极柱磁场还具有引导电子运动方向的作用，使部分电子从轴向运动转向径向运动。因此六极柱磁场大幅度增加放电室内电子的轨迹分布，进一步提升电子与推进剂气体的碰撞概率。 最后，基于上述离子源开发了紧凑型六极柱ECR推进器，其口径为38 mm，长为60 mm，重量为550 g，是目前世界上首个紧凑型2.45 GHz同轴微波六极柱ECR磁喷管推进器。该推进器在100 W微波功率与2 sccm氩气流量下测得的推力为T=1.172±0.14 mN，比冲为I_sp=2026 s，远高于目前见于报道的ECR推进器。因此，本文开发了紧凑型六极柱ECR推进器极具竞争力，在航天高效的轨道电推进系统中具有广阔的应用前景。关键词: 离子源；电子回旋共振；电推进器；磁喷管

Electron cyclotron resonance (ECR) magnetic nozzle thruster is a propulsion device that uses electromagnetic waves and magnetic fields to generate plasma jets. Due to the limitations of radio frequency physics, the size and efficiency of the ion source, the core component of the plasma thruster, is difficult to shrink. This article developed a compact hexapole ECR ion source for the ECR magnetic nozzle thruster. ECR is a phenomenon in which electrons and electric fields are coupled in frequency and phase to accelerate electrons and supply electron kinetic energy. Finally, the magnetic nozzle accelerates high-speed electrons and ions and leaves the thruster to form a plasma jet. This process does not require additional accelerating electrodes makes the overall structure very simple.Traditional ECR thrusters use a single ring magnet to construct a two-dimensional ECR resonance surface. This article uses two annular permanent magnets to form a magnetic mirror through magnetic field linking, which significantly extends the coverage of the ECR resonance surface in the discharge chamber. The main structure field of a 3-dimensional ECR resonance surface with an axial coverage rate of about 100 % and a radial coverage rate of about 94 % is obtained, significantly increasing the effective area for electrons to absorb electromagnetic waves. Therefore, the gas molecules passing through the discharge cell have a higher probability of being bombarded by high-energy electrons, thereby achieving a higher ionization efficiency of the propellant.The addition of a hexapole magnetic field based on the ECR main structure field solves the insufficient confinement capability of the axial magnetic mirror for radially moving electrons. The hexapole magnetic field further confines the electrons in the discharge chamber, which increases the residence time of the electrons and reduces the phenomenon of electrons bombarding the wall. In addition, the hexapole magnetic field also has the function of guiding the direction of electron movement so that part of the electrons move from axial movement to radial movement. Therefore, the hexapole magnetic field dramatically increases the trajectory distribution of the electrons in the discharge chamber and further increases the collision probability of the electrons and the propellant gas.Finally, a compact hexapole ECR thruster was developed based on the above ion source, with a diameter of 38 mm, a length of 60 mm, and a weight of 550 g. It is currently the world's first 2.45 GHz hexapole ECR thruster. The thrust measured by the thruster at 100 W microwave power and 2 sccm argon flow rate is T=1.172±0.14 mN, and the specific impulse is I_sp=2026 s, which is much higher than the ECR thruster currently the public article. Therefore, the compact hexapole ECR thruster developed in this article is very competitive and has broad application prospects in the aerospace electric propulsion system.Keywords: Ion source; Electron cyclotron resonance; Electric thruster; Magnetic nozzle