-
Internal field emission breakdown in the electro-dynamic structures of high-power microwave devices can seriously limit the devices’ output power and pulse duration. So an over-sized backward wave oscillator (BWO) is developed to increase the diameter of the electro-dynamic structure beyond the cut-off radius, and reduce these internal fields to levels, which are below critical breakdown levels. As a typical high power microwave (HPM) device, the oversized BWO is widely used and investigated. But some interaction phenomena between the beam and the microwave field in the device are not clearly understood because the beam-loaded effect is so obvious. And the physical process for the interaction is also considered to be complicated. Here as an oscillator, the feedback process is very important in the microwave device, which includes the oversized BWO. So the interaction process between the beam and the oversized BWO is explored from the feed back process instead of the field in the device. Then the physical mechanism for the feedback process in the oversized BWO is explored both in theoretical investigation and in particle-in-cell simulation. And the equivalent circuit is established for such a purpose. The mode control mechanism is explored based on the equivalent circuit. Finally an over-sized backward wave oscillator with rectangular profile corrugations is designed to produce TM01 high power microwave radiation without mode-competition. An RF power of 7.9 GW at a frequency of 8.68 GHz is obtained in the particle in cell simulation driven by the beam with a beam voltage of 1 MW and a current of 20 kA, and the corresponding efficiency is 39.5%.
-
Keywords:
- high power microwave /
- back-ward wave oscillator /
- mode-control /
- particle in cell
[1] Li Z H 2008 Appl. Phys. Lett. 92 054102
Google Scholar
[2] Korovin S D, Mesyats G A, Pegel I V, Polevin S D, Tarakanov V P 2004 IEEE Trans. Plasma Sci. 28 2691
[3] Li Z H, Zhou Z G, Qiu R 2014 Phys. Plasmas 21 103105
Google Scholar
[4] Xiao R Z, Zhang X W, Zhang L G 2012 Phys. Plasmas 19 073106
Google Scholar
[5] 杨振萍, 李正红 2008 物理学报 57 2627
Google Scholar
Yang Z P, Li Z H 2008 Acta Phys. Sin. 57 2627
Google Scholar
[6] 李正红, 常安碧, 鞠炳全 2007 物理学报 56 2603
Google Scholar
Li Z H, Chang A B, Ju B Q 2007 Acta Phys. Sin. 56 2603
Google Scholar
[7] Li, Z H 2005 Proceedings of IEEE International Symposium on Microwave, Antenna, Propagation and EMC Technologies for Wireless Communication Beijing 1 519
[8] Li Z H 2010 Phys. Plasmas 17 023113
[9] 李正红, 孟凡宝, 常安碧 2005 物理学报 54 3578
Google Scholar
Li Z H, Meng F B, Chang A B, 2005 Acta Phys. Sin. 54 3578
Google Scholar
[10] 李正红, 孟凡宝, 胡克松 2004 物理学报 53 3627
Google Scholar
Li Z H, Meng F B, Hu S K 2004 Acta Phys. Sin. 53 3627
Google Scholar
[11] Zhang J, Jin Z X, Yan J H, Shu T, Zhang J D 2015 IEEE Trans. Plasma Sci. 43 528
Google Scholar
[12] Jin Z X, Zhang J H, Zhong H H, Qian B L, Shu T 2011 Rev. Sci. Instrum. 82 084704
Google Scholar
[13] Wu Y, Xie H Q, Li Z H, Zhang Y J, Ma Q S 2013 Phys. Plasmas 20 113102
Google Scholar
[14] Xiao R Z, Chan C H, Zhang X W, Shun J 2009 J. Appl. Phys. 105 053306
Google Scholar
[15] Xiao R Z, Chan C H, Zhang X W 2013 Appl. Phys. Lett. 102 133504
Google Scholar
[16] Wu Y 2017 Phys. Plasmas 24 073105
Google Scholar
[17] Song W, Chen C H, Sun J, Zhang X W, Shao H 2012 Phys. Plasmas 19 1031111
-
图 1 器件结构图
Figure 1. Device’s structures.
图 2 器件等效电路图
Figure 2. Equivalent circuit.
图 3 谐振反射腔中微波场的Ez分量
Figure 3. RF field (Ez) in the resonate reflector.
图 4 SWS色散曲线
Figure 4. Dispersion curve of the SWS.
图 5 器件等效反馈放大电路
Figure 5. Feed back circuit of the device.
图 6 微波场强度
$\alpha '$ 随k的变化曲线Figure 6. RF field
$\alpha '$ versus k.
图 7 电子束通过器件时的微波场分布
Figure 7. RF field in the device.
图 8 电子束调制电流在器件中的变化曲线
Figure 8. Modulation current of the electron beam.
图 9 微波输出功率随时间的变化曲线
Figure 9. Output RF power versus time.
图 10 器件内部监察点A处微波电场的频谱
Figure 10. Spectrum of the RF field at the poit A in the device.
表 1 器件结构参数
Table 1. Parameters of the device.
Cavity radius of the resonate reflector Cavity width of the resonate reflector Drifting distance Outer radius of SWS Inner radius of SWS SWS’s period 3.2 cm 1.6 cm 5.4 cm 2.8 cm 2.5 cm 1.6 cm 
DownLoad: CSV
表 2 有初始调制(10.73 GHz)电子束在不同流强下的模拟微波输出功率
Table 2. Output RF power and frequency when the device is driven by the electron beam with the initial modulation at the frequency of 10.73 GHz.
Beam current /kA 10 12 14 16 18 20 22 With initial modulation RF power/GW 0.68 3.10 4.10 4.50 6.70 7.90 7.80 RF frequency/GHz 10.73 10.73 10.73 10.73 8.63 8.59 8.58 No initial modulation RF power /GW 0 0 5.20 6.50 7.70 7.90 7.80 RF frequency/GHz 8.69 8.66 8.63 8.59 8.58
DownLoad: CSV
-
[1] Li Z H 2008 Appl. Phys. Lett. 92 054102
Google Scholar
[2] Korovin S D, Mesyats G A, Pegel I V, Polevin S D, Tarakanov V P 2004 IEEE Trans. Plasma Sci. 28 2691
[3] Li Z H, Zhou Z G, Qiu R 2014 Phys. Plasmas 21 103105
Google Scholar
[4] Xiao R Z, Zhang X W, Zhang L G 2012 Phys. Plasmas 19 073106
Google Scholar
[5] 杨振萍, 李正红 2008 物理学报 57 2627
Google Scholar
Yang Z P, Li Z H 2008 Acta Phys. Sin. 57 2627
Google Scholar
[6] 李正红, 常安碧, 鞠炳全 2007 物理学报 56 2603
Google Scholar
Li Z H, Chang A B, Ju B Q 2007 Acta Phys. Sin. 56 2603
Google Scholar
[7] Li, Z H 2005 Proceedings of IEEE International Symposium on Microwave, Antenna, Propagation and EMC Technologies for Wireless Communication Beijing 1 519
[8] Li Z H 2010 Phys. Plasmas 17 023113
[9] 李正红, 孟凡宝, 常安碧 2005 物理学报 54 3578
Google Scholar
Li Z H, Meng F B, Chang A B, 2005 Acta Phys. Sin. 54 3578
Google Scholar
[10] 李正红, 孟凡宝, 胡克松 2004 物理学报 53 3627
Google Scholar
Li Z H, Meng F B, Hu S K 2004 Acta Phys. Sin. 53 3627
Google Scholar
[11] Zhang J, Jin Z X, Yan J H, Shu T, Zhang J D 2015 IEEE Trans. Plasma Sci. 43 528
Google Scholar
[12] Jin Z X, Zhang J H, Zhong H H, Qian B L, Shu T 2011 Rev. Sci. Instrum. 82 084704
Google Scholar
[13] Wu Y, Xie H Q, Li Z H, Zhang Y J, Ma Q S 2013 Phys. Plasmas 20 113102
Google Scholar
[14] Xiao R Z, Chan C H, Zhang X W, Shun J 2009 J. Appl. Phys. 105 053306
Google Scholar
[15] Xiao R Z, Chan C H, Zhang X W 2013 Appl. Phys. Lett. 102 133504
Google Scholar
[16] Wu Y 2017 Phys. Plasmas 24 073105
Google Scholar
[17] Song W, Chen C H, Sun J, Zhang X W, Shao H 2012 Phys. Plasmas 19 1031111
DownLoad:
Catalog
Metrics
- Abstract views: 7596
- PDF Downloads: 42
- Cited By: 0
