• The Journal of the Korea institute of electronic communication sciences
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• v.4 no.2
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• pp.82-86
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• 2009

In this paper, we have studied on the microstrip antenna for satellite DMB from 2.63 to 2.65 GHz. Microstrip patch antenna was designed using HFSS simulation program and fabricated by FR4 substrate that has substrate thickness of 1.6mm, metal thickness of $17{\mu}m$, and dielectric constant of 4.4, respectively.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2002.05a
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• pp.523-526
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• 2002

This paper presents the simulation of Au / $Ba_{x}$S $r_{1-x}$ Ti $O_3$(BSTO) / Magnesium oxide (MgO) multi-layered and electrically tunable band-pass filters (BPFs) by using high frequency structure simulator (HFSS). This model is a two-pole microstrip edge coupled filter. The filter was designed fur a center frequency about 5.8 GHz. The tunabillity of the filter is achieved using the nonlinear dc electric-field dependence on the relative dielectric constant of BSTO frroelectric thin film. This work seems very promising for future wireless communication systems....

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• v.9 no.2
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• pp.1091-1094
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• 2005

This paper presents analysis and design for printed directive antenna using Bluetooth AP system. For the miniaturization of the antennas, dielectric substrate (${\varepsilon}_r$=4.6) and planar line Yagi-Uda antenna structure are used. The proposed Yagj-Uda antennas are simulated using commercial simulator (HFSS). The results of the simulation are presented and compared with characteristics of each array type. Especially, the proposed antennas can be applied to the design of various communication systems for 2.4 GHz band.

• The Journal of the Korea institute of electronic communication sciences
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• v.14 no.1
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• pp.55-60
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• 2019

Because of an rapid increase of using a wireless Internet, the originally used communication of 2.4 GHz band was saturated and crossed and there were some problems. According to this, the development of a wireless Internet technology of 5 GHz Band proceeded. In the thesis we researched a Square Slot Microstrip Patch Antenna available in 5 GHz band of wireless communication. The research designed and analyzed the Antenna through HFSS. Ultimately, we compared and analyzed made Antenna through a Network Analyzer.

• Journal of Information Processing Systems
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• v.15 no.1
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• pp.189-202
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• 2019

During thermal power coal-fired boiler operation, it is very important to detect the pulverized coal concentration in the air pipeline for the boiler combustion stability and economic security. Because the current measurement methods used by power plants are often involved with large measurement errors and unable to monitor the pulverized coal concentration in real-time, a new method is needed. In this paper, a new method based on microwave circular waveguide is presented. High Frequency Electromagnetic Simulation (HFSS) software was used to construct a simulation model for measuring pulverized coal concentration in power plant pipeline. Theoretical analysis and simulation experiments were done to find the effective microwave emission frequency, installation angle, the type of antenna probe, antenna installation distance and other important parameters. Finally, field experiment in Jilin Thermal Power Plant proved that with selected parameters, the measuring device accurately reflected the changes in the concentration of pulverized coal.

• Journal of the Microelectronics and Packaging Society
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• v.19 no.3
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• pp.43-48
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• 2012

Errors of relative permittivity calculation caused by the variation of sample aspect ratio (diameter/height) and measuring geometry were analyzed by computer simulation and measurement. Firstly, the $S_{21}$ spectrum of the sample (permittivity 38) was simulated in the post resonator measuring apparatus by HFSS simulation. Then, the relative permittivity was calculated from the $TE_{011}$ mode resonant frequency. The relative permittivity varied by ca. 0.3% with sample aspect ratio variation (D/H=0.8~1.6). The relative permittivity varied by ca. 1~10% when the 1~10% of air-gap was introduced in between the dielectric disk and upper conductor. All the simulation results showed consistent tendency with real measurement.

• Safety and Health at Work
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• v.8 no.3
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• pp.237-245
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• 2017

Background: Solar furnaces are used worldwide to conduct experiments to demonstrate the feasibility of solar-chemical processes with the aid of concentrated sunlight, or to qualify high temperature-resistant components. In recent years, high-flux solar simulators (HFSSs) based on short-arc xenon lamps are more frequently used. The emitted spectrum is very similar to natural sunlight but with dangerous portions of ultraviolet light as well. Due to special benefits of solar simulators the increase of construction activity for HFSS can be observed worldwide. Hence, it is quite important to protect employees against serious injuries caused by ultraviolet radiation (UVR) in a range of 100 nm to 400 nm. Methods: The UV measurements were made at the German Aerospace Center (DLR), Cologne and Paul-Scherrer-Institute (PSI), Switzerland, during normal operations of the HFSS, with a high-precision UV-A/B radiometer using different experiment setups at different power levels. Thus, the measurement results represent UV emissions which are typical when operating a HFSS. Therefore, the biological effects on people exposed to UVR was investigated systematically to identify the existing hazard potential. Results: It should be noted that the permissible workplace exposure limits for UV emissions significantly exceeded after a few seconds. One critical value was strongly exceeded by a factor of 770. Conclusion: The prevention of emissions must first and foremost be carried out by structural measures. Furthermore, unambiguous protocols have to be defined and compliance must be monitored. For short-term activities in the hazard area, measures for the protection of eyes and skin must be taken.

• Journal of the Institute of Electronics Engineers of Korea TC
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• v.47 no.11
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• pp.77-83
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• 2010

This paper presents the dual resonance PIFA(Planar Inverted F-Antenna) which satisfies the requirements of the 802.11n standard at both 2.4 GHz and 5 GHz frequency bands. Patch for 2.4 GHz and U-Type slot for 5 GHz were used for dual resonance, respectively. In this paper, the characteristics of an antenna were investigated by varying locations of short plate and feed point, the width of the short plate, the thickness and the location of U-Type slot. To investigate the characteristics of the PIFA, HFSS(High Frequency Structure Simulation) for the simulation was used. And the measurement results of a fabricated PIFA were compared with the simulated ones. The measurement and simulation results show that good dual resonance characteristics as the thickness of U-type slot decreases and when the location of U-type slot is far from the feed point.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.24 no.5
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• pp.515-524
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• 2013

The program for dielectric ceramic waveguide filter was developed based on the direct coupled filter of ${\lambda}/2$ step impedance prototype. This developed program was called DWFD(Direct coupled Waveguide Filter Design). The filter was designed by 3-dimensional laminated type to reduce the size at the 1 GHz. S scattering matrix for this filter was calculated using the DWFD program. The width of inductive irises for laminated filter was computed by HFSS simulation tool. This waveguide filter was designed by 8 poles with bandwidth 25 MHz at the center frequency 881.5 MHz. By using a dielectric constant 35.4 and laminated type, the size of filter was reduced with width 50 mm and height 48 mm rapidly. We can see that the measured results agree well with the HFSS simulation result. Finally, this paper is shown that the design and implementation of waveguide filters can be presented by using DWFD program simply.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.17 no.2
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• pp.259-264
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• 2016

In this study, the properties of a patch antenna fed by a coplanar waveguide with ground (CPWG) and design method were studied. The antenna was impedance-matched to the CPWG feedline by adjusting the width, length, and position of the patch. To improve the frequency properties of the CPWG type antenna, patch length, patch width, patch position, and ground distance were simulated using HFSS (High Frequency Structure Simulator) simulation program. A CPWG antenna of 1.8 GHz for LTE band was designed and fabricated by photolithography on an FR4 substrate (dielectric constant of 4.4 and thickness of 0.8 mm). The fabricated antenna was analyzed using a network analyzer. The measured results agree well with the simulations, which confirmed the validity of this study. The fabricated CPWG antenna showed a center frequency, minimum return loss and -10dB bandwidth of 1.8GHz, -32.1dB, 22MHz and $50.2{\Omega}$ respectively. The proposed antenna is expected to be applicable to the LTE band.