• KIEE International Transactions on Electrophysics and Applications
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• 제4C권6호
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• pp.282-287
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• 2004

Since the manufacturing process in the LTCC process does not allow solid ground planes between ceramic layers to isolate the signal lines, the buried ground should be realized as a meshed ground plane. Both characteristic impedances of the signal lines and couplings between different signal layers are influenced by the properties of these meshed planes. In this paper, we propose a new analysis method for coupling behavior between internal transmission lines, which are isolated by the buried meshed-ground planes. The coupling behavior between layers isolated by meshed-ground planes is investigated by the coupled-transmission line model for the isolated layers. The coupling factors between isolated lines with the meshed-ground are extracted by 2-D FEM calculations.

• Journal of electromagnetic engineering and science
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• 제13권1호
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• pp.51-53
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• 2013

A MIMO antenna using the resonance of ground planes is proposed for 4G mobile application. A resonant mode is generated when the double ground planes (upper and lower) in the mobile terminal are excited as the radiator. By combining the resonant modes contributed from both the antenna element and the ground planes, the proposed MIMO antenna realizes a wideband property over LTE band 13. In addition, an inductive coil is employed to reduce the antenna volume. These approaches not only simplify antenna design but also effectively improve bandwidth and efficiency. The proposed MIMO antenna has an excellent ECC value of below 0.1 because of the nearly orthogonal radiation patterns of the two radiators. Moreover, an additional antenna is adopted to cover WiMAX, WLAN, and Bluetooth services simultaneously in frequency range from 2 GHz to 2.7 GHz.

• Journal of Electrical Engineering and Technology
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• 제7권3호
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• pp.406-410
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• 2012

This paper looks into the field inside the wide rectangular box structure that is excited by the High Power Electromagnetic(HPEM) source as a potential threat to electric grid and communication networks causing malfunction or destruction. The rectangular box is assumed power/ground planes and its internal field is calculated by the cavity model with the lightning strike excitation as an HPEM pulse. The accuracy of the calculation method employed here is validated through a $156mm{\times}106mm{\times}508{\mu}m$ parallel metallic plate case which is manufactured and tested, and is applied to the size of a building. With the help of the cavity model that takes into account loading, the level of the electric field is shown to decrease when a metal pillar is loaded between the power and ground planes.

• Journal of electromagnetic engineering and science
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• 제7권1호
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• pp.7-11
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• 2007

PCB Power-Bus (comprising power/ground planes) impedance and fields are evaluated by an efficient series expansion method that is suggested in this paper. It is used to investigate the structure's radiated emission(RE) levels and find acceptable ways of loading the power/ground planes such as decoupling capcitor(DeCap)s, balanced feeding and slits, in order to reduce the interferences. Also, the calculations and measurements of a proposed geometry are verified by vector fitting as a analysis model to check the behavior of the slit.

• Journal of electromagnetic engineering and science
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• 제19권1호
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• pp.1-5
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• 2019

In this study, optimum locations for a loop-type ground radiation antenna are evaluated for C-shaped ground planes of two different sizes. To achieve good radiation performance, the antenna needs to be located such that it couples with the dominant current mode of the ground plane. Antenna locations are proposed using the characteristic mode analysis of the ground planes. The measured bandwidths of the antennas at the proposed locations have more than twice the bandwidths of the cases in which the antennas are coupled with non-dominant modes. The operating frequency of the antennas is 2.45 GHz.

• 한국항행학회논문지
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• 제28권2호
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• pp.246-249
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• 2024

In this paper, we present a miniaturized differential line (DL) using inductance-enhanced corrugated ground planes (LCGP) for effective common-mode (CM) noise suppression in high-speed packages and printed circuit boards. The LCGP-DL demonstrates the CM noise suppression in the frequency range from 2.09 GHz to 3.6 GHz. Furthermore, to achieve the same low cutoff frequency, the LCGP-DL accomplishes a remarkable 23.2% reduction in size compared to a reference DL.

• 한국전자파학회논문지
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• 제22권7호
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• pp.675-682
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• 2011

본 논문에서는 두 개의 접지 평판 사각형 개구를 관통하는 대칭 평행 2선 전송 선로에 대하여 접지 평판 개구의 크기 변화가 전송 선로의 특성에 미치는 영향을 검토하였다. 이론 해석에는 상용 툴인 CST MWS를 사용하였으며, 두 개의 사각형 개구의 가로 및 세로 길이 변화에 따른 삽입 손실 특성을 계산하였다. 그 결과, 개구의 가로 길이 및 세로 길이에 따른 삽입 이득 및 삽입 손실 현상을 관찰할 수 있었으며, 접지 평판 사이의 선로 길이는 개구가 선로와 가까이 존재할 때 전체 전송 선로의 길이가 반 파장이 되는 주파수를 주기로 하여 삽입 이득 및 삽입 손실이 주기적으로 나타남을 확인할 수 있었다. 전송 선로 부하단의 삽입 손실 측정 결과를 수치 계산 결과와도 비교하여 이론 해석의 타당성을 확인하였다.

• 한국터널지하공간학회 논문집
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• 제5권3호
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• pp.217-226
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• 2003

본 연구에서는 활동성 불연속면을 포함하고 있는 모래지반에 터널을 굴착할 때에 터널 주변의 원지반에 발생되는 아칭을 규명하기 위하여 터널 상부의 토피고와 불연속면의 위치 및 각도를 변화시켜가며 모형실험을 수행하였다. 모형실험기의 중앙에 수직으로 이동이 가능한 가동판을 설치하고 모래지반 조성 후에 가동판을 강하시켜서 터널 굴착을 모형화 하였고, 토조의 바닥판에 로드셀을 부착하여, 아칭에 의한 하중전이를 측정하였다. 굴착에 의한 지표면의 침하거동은 변위측정센서를 지표면에 설치하여 측정하였으며, 실험 중에 연속사진촬영을 실시하고 지반조성시 일정한 간격으로 설치한 측점의 움직임을 관측하여 굴착에 의한 지반이완형태를 측정하였다. 본 연구 결과 터널굴착시 불연속면의 각도와 위치, 그리고 터널 상부의 토피고에 따라서 하중전이 형태와 이완영역이 변화하는 것을 확인하였으며 지반의 이완영역이 터널과 인접해 있는 불연속면을 따라 주변지반으로 점차 확대되어 가는 것을 알 수 있었다.

• International Journal of Computer Science & Network Security
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• 제21권12호
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• pp.75-80
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• 2021

In this paper, a dual-band Koch Snowflake antenna is proposed for wireless communication systems. Fractal geometry, CPW-feed and stepped ground planes are used to improve the impedance bandwidth. By properly introducing a hexagonal split-ring slot to radiating element, a lower frequency band is generated. The proposed structure is fabricated and tested. Experiment results exhibit dual-band of 0.73-0.98 GHZ and 1.6-3.1 GHz which makes this antenna suitable candidate for GSM900, GSM1800, UTMS2100, Wi-Fi 2400 and LTE2600 bands. In addition, a good radiation pattern, a satisfactory peak gain and a radiation efficiency, which reaches 95%, are achieved.

• 한국전자파학회지:전자파기술
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• 제24권2호
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• pp.35-50
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• 2013

This paper discusses effects of mesh planes on signal integrity in high-speed glass ceramic packages. One of serious signal integrity issues in high-speed glass ceramic packages is high far-end (FE) noise coupling between signal interconnects. Based on signal integrity analysis, a methodology is presented for reducing far-end noise coupling between signal interconnects in high-speed glass ceramic modules. This methodology employing power/ground mesh planes with alternating spacing and a via-connected coplanar-type shield (VCS) structure is suggested to minimize far-end noise coupling between signal lines in high-speed glass ceramic packages. Optimized interconnect structure based on this methodology has demonstrated that the saturated far-end noise coupling of a typical interconnect structure in glass ceramic modules could be reduced significantly by 73.3 %.