毫米波慢波振荡器研究

【作者】 肖琴；

【导师】 鄢扬；

【作者基本信息】 电子科技大学 ， 等离子体物理， 2007， 硕士

【摘要】 高功率毫米波器件是高功率微波技术的一个重要方向,而慢波器件是其中的一个重要分支,是目前国内外研究的热点。本文对慢波器件进行了比较深入、全面的研究,包括理论分析、数值计算、CST软件模拟、MAGIC粒子模拟四个方面,取得了一定的研究成果。首先,利用场匹配的方法,采用线性理论、Floquet定理,推导出盘荷加载周期慢波结构的色散关系方程和耦合阻抗。应用商业模拟软件CST Microwave Studio仿真计算了盘荷加载慢波周期结构和变形盘荷加载周期慢波结构的色散曲线,并与数值计算所得色散曲线进行对比验证。其次,研究了几种有效抑制过模慢波系统中模式竞争的结构,这对于采用过模慢波结构来增加功率容量,以提高微波输出功率的方法是非常必要的。再次,使用MAGIC程序对两种具有大口径(即过模)慢波结构所构成的毫米波慢波振荡器进行了粒子模拟研究,并采用抑制模式竞争的不同方法来达到提高输出毫米波功率和有效抑制竞争模式。通过粒子模拟,观察到了电子注与电磁波相互作用的清晰的物理过程,研究了器件产生微波频率和功率随结构参数和导引磁场的变化关系。研究发现:分段式变形盘荷加载慢波振荡器在8毫米波段,注波互作用产生的微波功率高,频谱质量好。粒子模拟的结果表明:采用此结构设计的工作频率为35.2GHz的慢波振荡器产生了650MW的微波输出,工作模式为TM 01模。而带有前谐振腔的盘荷加载分段式慢波振荡器工作在3毫米波段,又比不带腔体结构产生了更高的输出功率,频谱质量也更好。粒子模拟的结果表明:工作频率在100GHz时,微波输出功率可达565MW,工作模式为TM01模。更多还原

【Abstract】 High power millimeter microwave device is an important part of high power microwave technology. Slow-wave device is interested by the scientists all over the world. This dissertation gives theoretical, numerical, software and PIC simulative research on the high-power millimeter wave band Slow-wave device. Several valuable academic achievements are obtained.First, successfully using general method is applied to two typical slow-wave structure (SWS), namely disk-loaded and modified disk-loaded structures. In principle, the linear analysis can be applied to efficiently calculating all kinds of beam-wave interaction in various Slow-wave devices composed of axisymmetric SWSs with arbitrary periodic profile. Then, calculate the dispersion equation; draw the dispersion curve by two ways. Compare the two methods and make sure that the CST software simulation is reliable.Second, study several methods which are effective to restrain the competition of modes. Solve the problem of the modes’competition is very important for increasing the output power of Overmode high power millimeter wave oscillator.Third, particle simulation method is used to investigate the properties of the millimeter wave band device with large diameter, short period and two section SWSs, with frontal or back resonator. Both disk-loaded and modified disk-loaded structures are studied. This work includs the basic physical processes of the beam-wave interactions and the dependence of the microwave radiation on the structure parameters, and the guiding magnetic field intensity. The simulation results confirm that the modified disk-loaded structure with two section SWSs can generate the highest output power at 8 mm band, and the disk-loaded structure with frontal resonator can generate the highest output power at 3 mm band. A set of optimum parameters are given. The typical simulation results are that, the output power of 8 mm band is 650MW, and the output power of 3 mm band is 565MW. TM 01mode is the operating mode of the two devices. The results of PIC simulation provide theory foundation for subsequent experiment study.更多还原