• Title, Summary, Keyword: Microwave Tube

Search Result 45, Processing Time 0.035 seconds

A Study on Measuring Technique of Electromagnetic Wave Absorbing Characteristics of Microwave Absorbers (전파흡수체의 전파흡수특성측정기법에 관한 연구)

  • 김동일;안영섭;정세모
    • Proceedings of the Korean Institute of Navigation and Port Research Conference
    • /
    • /
    • pp.2-29
    • /
    • 1992
  • According to the increase of occupation density of microwave frequency band on use microwave environments have been congested extensively. For shielding unnecessary electromagnetic wave of preventing the electromagnetic wave reflection a good conductor a low resistive material or a lossy material is mainly used. As a method to measure the absorbing characteristics of microwave absorber the fundamental microwave measuring method can be used. There is however a big problem in measuring errors since the wavelength of microwave is very short especially as in the case as microwave absorber for RADAR. Therefore this research aimed to a converting adaptor of 20mm${\Phi}$ coaxial tube from a Type-N connector to 20mm${\Phi}$ coaxial tube and to use it for designing microwave absorber and evaluating absorbing characteristics. Furthermore the measurements of absorbing characteristics and material constants have performed and reviewed which were carried out by using the coaxial tube in the short type and by using rectangular waveguide respectively As a result the validity of the measured values have been confirmed.

  • PDF

Fabrication of Microwave PECVD with Linear Antenna for large-scale deposition processing, and Analysis of Ar plasma characteristics using Electrostatic Probe and Temperature Characteristics (대면적 증착용 선형 초고주파 플라즈마 장치 제작 및 정전 탐침법을 이용한 Ar 플라즈마 특성 분석과 온도 특성 분석)

  • Han, Moon-Ki;Seo, Kwon-Sang;Kim, Dong-Hyun;Lee, Ho-Jun
    • The Transactions of The Korean Institute of Electrical Engineers
    • /
    • v.64 no.3
    • /
    • pp.422-428
    • /
    • 2015
  • A 2.45GHz microwave plasma source with a linear antenna has been developed for low temperature large scale deposition processing. Microwave power is transmitted through WR340 waveguide and a copper rod, linear antenna, is located in a quartz tube. The power matching is effectively achieved by a linear antenna is located at ${\lambda}_g/4$ or $3{\lambda}_g/4$ from the end of WR340 waveguide. The Ar plasma was generated along the surface of quartz tube and a clear standing wave pattern with nearly 10cm wavelength was observed at Ar pressure of 200mTorr and 200W input power. The electron density and electron temperature were investigated by using the electrostatic probe. The electron density and electron temperature were highly measured near the surface of quartz tube. Ar plasma density along the quartz tube is mostly uniform despite standing wave set-up and antenna of long length. A uniform temperature was measured at 10~40cm distance from the end quartz tube and 5cm distance from the surface of quartz tube.

A Study on Measuring Technique of Characteristics for Electromagnetic Wave of Microwave Absorbers (전파흡수체의 전자파적 특성측정기법 연구)

  • Kim, Dong-Il;Chung, Se-Mo;Ahn, Young-Sup
    • Journal of the Korean Institute of Navigation
    • /
    • v.16 no.4
    • /
    • pp.25-34
    • /
    • 1992
  • As a method of measure the absorbing characteristics of microwave absorber, the various microwave measuring method can be used fundamentally. There is, however, a big problem in measuring errors, since the wavelength of microwave such as used for radar is very short. Therefore, this research aimed to design and fabricate a converting adaptor of $20mm^{\phi}$ coaxial tube from a Type-N connector to $20mm^{\phi}$ coaxial tube and to use it for evaluating absorption characteristics of microwave absorber. Furthermore, the measurements of absorbing characteristics and material constants have been performed and review, which were carried out by using the coaxial tube and by using rectangular waveguide, respective. As a result, the validity of the proposed measuring method has been confirmed.

  • PDF

A Study on Measuring Technique of Electromagnetic Wave Absorbing Characteristics of Microwave Absorbers (전파흡수체의 전파흡수특성 측정기법에 관한 연구)

  • 김동일;안영섭;정세모
    • The Proceeding of the Korean Institute of Electromagnetic Engineering and Science
    • /
    • v.4 no.1
    • /
    • pp.10-19
    • /
    • 1993
  • As a method to measure the absorbing characteristics of microwave absorber, the various microwave measuring method can be used fundamentally. There is, however, a big problem in measuring errors, since the wavelength of microwave such as used for radar is very short. Therefore, this research aimed to design and fabricate a converting adaptor of 20mm .PHI. coaxial tube from a Type - N connector to $20mm\phi$ coaxial tube and to use it for evaluating absorption characteristics of microwave absorber. Furthermore, the measurements of absorbing characteristics and material constants have been performed and reviewed, which were carried out by using the coaxial tube and by using rectangular waveguide, res- pectively. As a result, the validity of the proposed measuring method has been confirmed.

  • PDF

Implementation of Traveling Wave Tube Amplifier Maintenance System for the Microwave Surveillance Radar (마이크로파 탐색레이더 진행파관증폭기 정비시스템 구현)

  • Yoon, In-Chul;Kwon, Jong-Woon;Park, Yong-Man;Odgerel, Odgerel;Kim, Hie-Sik
    • Proceedings of the KIEE Conference
    • /
    • /
    • pp.264-266
    • /
    • 2006
  • This traveling wave tube amplifier maintenance system was developed for performance of microwave Surveillance radar traveling wave tube amplification parts, and field operation. The Maintenance system is traveling wave tube amplification part RF output waveform measurement and HVPS Voltage adjustment and a maintenance function are offer. The system was developed as an embedded system base it consisted of Linux os which applied a top-down design and visual technique. Therefore change and easy extension of a system. This paper discussed characteristic of maintenance equipment function, composition, and an employment program.

  • PDF

Characterization of Linear Microwave Plasma using the Fluid Simulation (유체 시뮬레이션을 이용한 선형 마이크로웨이브 플라즈마의 특성 분석)

  • Seo, Kwon-Sang;Han, Moon-Ki;Kim, Dong-Hyun;Lee, Ho-Jun
    • The Transactions of The Korean Institute of Electrical Engineers
    • /
    • v.64 no.4
    • /
    • pp.567-572
    • /
    • 2015
  • Discharge characteristics of linear microwave plasma were investigated by using fluid simulation of 2D axis-symmetry based on finite elements method. The microwave power was 2.45 GHz TEM mode and transmitted through linear antenna. Resistive power and pressure were considered simulation variables and argon was used for working gas. A decrease of electron density along the quartz tube was observed in low power condition but relatively uniform plasmas were generated in chamber by increasing the resistive power. The electron temperature was highly detected near the surface of quartz tube because the electron was heated only dielectric surface. The power transmission efficiency decreased and characteristics of surface plasma were observed in high electron density condition.

Design and Fabrication of a Dual Cylindrical Microwave and Ohmic Combination Heater for Processing of Particulate Foods

  • Lee, Seung Hyun;Choi, Won;Park, Sung Hee;Jun, Soojin
    • Journal of Biosystems Engineering
    • /
    • v.40 no.3
    • /
    • pp.250-260
    • /
    • 2015
  • Purpose: Dual cylindrical microwave chambers equipped with an ohmic heating tube were designed and fabricated to maximize the electric field strength for expeditious heat treatment of particulate foods. Methods: The efficacy of the combination heater was investigated by simulating the electric field distribution by using COMSOL Multiphysics software. Results: All components of the designed microwave heating unit were suitable for transmitting maximal microwave power to the load. The simulated electric field distribution implied that single-mode microwave heating would be sufficient for the steady generation of a highly localized heating zone in the cavity. During impedance matching, the calculated reflection coefficient ($S_{11}$) was small, possibly implying minimal power loss and wave reflection in the designed microwave heating chamber. Conclusions: This study demonstrates the possibility of concentrating the microwave power at the centerline for a single-frequency microwave, for thermal treatment of multiphase foods without attenuating the microwave power.

The Properties of Microwave Propagation in Discharging Plasma (방전에 의한 프라즈마에서의 마이크로파 전파특성)

  • Yang, In-Eung;No, Bang-Hyeon;Kim, Bong-Yeol
    • Journal of the Korean Institute of Telematics and Electronics
    • /
    • v.5 no.3
    • /
    • pp.31-39
    • /
    • 1968
  • In this paper microwave power propagated through the cold plasma was analyzed and measured with respect to the external magenetic flux density. The d. c discharge plasma was in the rectangular waveguide in which two electrode was inserted, and also the glass diseharge tube inserted in the ractangular wavegside. The direction of microwave pro-pagation, the axis of the discharge tube and external magnetic flux were perpendicular to each other. It showed that the attenuation and absorption of micro wave power propagated in the plasma was increased as the magnetic flux density, the discharge current and the pressure of the gas were increased.

  • PDF

Destruction of $SO_2$ and NO on the Carbon-bed by Microwave

  • Kim, Dong-Sik;Lee, Dong-Kyu
    • Carbon letters
    • /
    • v.1 no.1
    • /
    • pp.31-35
    • /
    • 2000
  • [ $SO_2$ ]and NO gases that come from the flue gases of most of all industrial combustion processes are harmful to everything include person and industrial facilities. For the simplification of the environmental clean-up processes, we studied the decomposition process by microwave. The microwave can destroy molecules into elementary atoms and offers energy to the atoms to react with carbons. Since the microwave is not absorbed into quartz tube and metallic chamber, the air pollution gases can be removed with much lower energy than in the case of conventional methods. We studied the decomposition of $SO_2$ and NO gases on the carbon beds by microwave. In the microwave field, the gases can be decomposed to form other compounds, such as elementary sulfur, nitrogen, carbon monoxide and carbon dioxide. It was found that CO gas is formed at higher temperature than is $CO_2$ gas, so it needs to control the bed temperature depend on products that we want to get.

  • PDF

Study on Recovery of Polymeric Raw Materials from WastePolystyrene in Motor Oil using Microwave Thermal Decomposition (마이크로웨이브 열분해(熱分解)를 이용(利用)한 폐(廢) 폴리스티렌과 모터 오일 혼합물(混合物)로부터 고분자(高分子) 원료(原料) 물질(物質) 회수(回收)에 관한 연구(硏究))

  • Kang, Tae-Won
    • Journal of the Korean Institute of Resources Recycling
    • /
    • v.15 no.5
    • /
    • pp.11-16
    • /
    • 2006
  • A novel microwave-induced pyrolysis was used for the recovery of valuable products from waste polystyrene in motor oil. Quartz tube was introduced as microwave reactor and silicon carbide was used as the microwave absorbent. In the experiments, different pyrolysis conditions were applied, such as time range from 30 minutes to 1 hour and microwave input power range from 180 to 250W. The distillate products from pyrolysis were analyzed with GC/MS. Styrene, 1-methyl styrene, toluene, ethyl benzene were the four main products. Styrene recovery rate from polystyrene was around 50%. Temperature for the complete pyrolysis using microwave was around $300^{\circ}C$ which is much lower than that of conventional thermal pyrolysis.