• Proceedings of the Korean Institute of Navigation and Port Research Conference
• /
• 1992.10a
• /
• 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.

• 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.

• 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.

• 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.

• Resources Recycling
• /
• v.15 no.5 s.73
• /
• 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.

• Proceedings of the KIEE Conference
• /
• 2006.04a
• /
• 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.

• 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.

• 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.

• 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.

• Journal of the Korean Institute of Navigation
• /
• v.15 no.1
• /
• pp.1-9
• /
• 1991

The coaxial sample holder with 20mm in diameter and the adaptor from type N connector-to-20mm${\phi}$ coaxial tube are designed and manufactured which have been used for designing and measuring the fabricated microwave absorber. In addition, the measure in method of material constants of the microwave absorbers is described, which is focused on minimizing the error due to the sample's shapes, the fitting conditions, etc. After describing the design method of a single-layed microwave absorber, the microwave absorbers for X-band, C-band and S-band RADARs are designed and fabricated, respectively, which are composed of ferrite, carborn, and binder and have good performance. Futhermore, we develop the high performance microwave absorber in extremely wide-band type for RADAR, which is composed of different material and its mixing ratio and which could cover nearly from 4 to 10 GHz.