• Title, Summary, Keyword: 삽입손실

Search Result 941, Processing Time 0.038 seconds

Evaluation of Y-Cap Capacitance in EMI Filter Design Using Measured S-Parameter (측정된 S-파라메터를 이용한 EMI 필터의 Y-캡 용량 산정에 대한 연구)

  • Kim, Jonghyeon;Jeon, Jiwoon;Kim, Taeho;Kim, Sungjun;Nah, Wansoo
    • The Journal of Korean Institute of Electromagnetic Engineering and Science
    • /
    • v.25 no.3
    • /
    • pp.319-332
    • /
    • 2014
  • Insertion loss is used as the character to express the efficiency of EMI filter. In this paper, we studied the better method that can measure the insertion loss of EMI filter exactly than the original method. For the achievement of this, the method measuring both common mode(CM) and differential mode(DM) insertion loss with arbitrary input/output impedance is accomplished using a 4-ports S-parameters system for consideration of unbalanced factor. Using this method, when input/output used in specific system is known, CM/DM insertion loss of EMI filter inserted in the system can be calculated. Finally, we applied 4-ports modeling method to 'X/Y capacitor part' and suggested the algorithm for selecting suitable the value of Y-capacitor using mixed mode S-parameters and mixed mode chain S-parameters.

Insertion Loss Characteristics of a Parallel Two-Wire Transmission Line with Equal Line Length Due to a Rectangular Aperture Sizes in Dual Ground Planes (두 개의 접지 평판 사각형 개구의 변화에 따른 평행 2선 전송 선로의 삽입 손실 특성)

  • Jung, Sung-Woo;Lim, Sung-Min;Jin, Jung-Hi;Kim, Ki-Chai
    • The Journal of Korean Institute of Electromagnetic Engineering and Science
    • /
    • v.22 no.7
    • /
    • pp.675-682
    • /
    • 2011
  • This paper presents two ground plane effects due to the size of two rectangular apertures for two-wire transmission line with equal line length crossing the changeable rectangular apertures in infinite ground planes. The CST MWS is used to determine the characteristics of the insertion loss of the transmission line from the load section in accordance with the ground plane aperture size. The results show that the insertion gain and the insertion loss are periodically observed for the multiple frequency of the half wavelength resonance by the wire length when the transmission line is nearby to horizontal side or vertical side of the aperture. The measurements of the insertion loss are performed to verify the theoretical analysis.

Prototype Phase Array Antenna using Ferroelectric Phase Shifter (강유전체 위상변위기를 이용한 위상배열 안테나)

  • Moon, Seung-Eon;Ryu, Han-Cheol;Kwak, Min-Hwan;Kim, Young-Tae;Lee, Sang-Seok;Lee, Su-Jae
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
    • /
    • /
    • pp.127-130
    • /
    • 2003
  • 4-bit 강유전체 위상변위기를 이용하여 10 GHz, 상온에서 작동하는 위상배열 안테나를 설계 및 제작하였다. 이 안테나는 빔 스캔을 위하여 전압에 대한 비선형특성을 보이는 강유전체 Bal-xSrxTiO3 (BST)를 기본으로 하는 위상변위기를 이용하였다. 우리는 펄스레이져 증착법으로 MgO (001) 기판위에 걸맞게 증착된 BST 박막을 일반적인 사진공정과 식각법을 이용하여 동일평판형 전극을 가진 위상변위기를 만들었다. 일반적인 동일평판형 강유전체 위상변위기의 경우 연결 전송선로의 임피던스와의 차이로 인해 반사손실과 이로 인한 부가적인 삽입손실이 발생한다. 이런 손실들을 줄이기 위해 입력과 출력 포트에 임피던스 매칭을 하였다. 이렇게 테이퍼링되어 만들어진 동일평판형 위상변위기는 이전의 구조에 비해 반사 손실과 삽입 손실 값에서 각각 약 10, 2 dB 정도씩의 개선을 보였다. 이 구조로 전송선로의 길이를 길게하여 만든 1-bit 강유전체 위상변위기는 10 GHz, 150 V의 전압변화에서 180도의 차등위상변위를 보였으며 최대 삽입손실과 최대 반사손실은 각각 약 10 dB, 20 dB 이다. 안테나 모듈은 4개의 마이크로스트림 패치 안테나와 4개의 강유전체 위상변위기로 이루어졌는데 10 GHz, 150 V의 전압변화에서 약 15도의 빔 스캔을 확인하였다.

  • PDF

A Study on the Design of Image Rejection Interdigital-Filter(IRIF) for 5.8GHz Wireless LAN (5.8GHz 무선 LAN용 영상제거 인터디지털 필터 설계에 관한 연구)

  • 유재문;강정진;안정식
    • Journal of the Korean Institute of Telematics and Electronics T
    • /
    • v.35T no.3
    • /
    • pp.31-36
    • /
    • 1998
  • In this paper, Image Rejection Interdigital Filter(IRIF) for 5.8GHz wireless LAN was designed and implemented. When the input signal is -30dBm in the 4~8㎓ frequency band, the insertion loss including all kinds of loss is 6.3dB in the center frequency 5.775GHz. Therefore, it was showed practically insertion loss of about -3.3dB. Especially, image signal rejection is about -l7dB in the image frequency 6.475GHz. and skirt characteristics of the high frequency band is very excellent. Therefore, it was confirmed that the proposed IRIF is suitable for RF image signal rejection in the 5.8GHz wireless LAN system.

  • PDF

Characteristics of Insertion Loss of Transmission Line with Different Line Length Crossing a Rectangular Aperture in a Backplane (백 플레인의 개구를 통과하는 길이가 다른 전송 선로의 삽입 손실 특성)

  • Jung, Sung-Woo;Kim, Ki-Chai
    • The Journal of Korean Institute of Electromagnetic Engineering and Science
    • /
    • v.19 no.2
    • /
    • pp.237-243
    • /
    • 2008
  • This paper presents the backplane effects for two-wire transmission line with different line length crossing the rectangular aperture in an infinite ground backplane. The FDTD method is used to determine the characteristics of the backplane insertion loss and return loss of the transmission line in accordance with the transmission line spacing and additional wire lengths. The results show that the insertion gain is obtained for the narrow spacing of the transmission line and the insertion loss is appeared for the transmission line with the additional wire The measurements of return loss are performed to verify the theoretical analysis.

Acoustic Performance Evaluation and Prediction for Low Height Noise Barriers Installed Adjacent To Rails Using Scale Down Model (축척 모형을 이용한 근접 저상 방음벽의 음향성능평가 및 예측)

  • Yoon, Je Won;Jang, Kang Seok;Cho, Yong Thung
    • Journal of the Korean Society for Railway
    • /
    • v.19 no.2
    • /
    • pp.124-134
    • /
    • 2016
  • Research on low height noise barriers installed adjacent to railways to reduce the height of the noise barrier has actively progressed in many countries except Korea. The performance of low height noise barriers is evaluated to identify barrier acoustic characteristics using a scale model of the barrier in the present research. As shown in the experimental results, if it is considered the installation of 'ㄱ' type noise barrier, sound absorption material should be installed on both the top and the vertical surfaces of the barrier to improve insertion loss. Also, an analytical method such as the boundary element method, rather than a simple empirical equation, is required to evaluate the insertion loss of the barrier. In addition, noise level increase in passenger position is very small if a barrier with sound absorption material is installed. Finally, the two dimensional boundary element method is implemented to predict the acoustic characteristics of the low height barrier; the possibility of the application is confirmed from a comparison of the results of measurements and predictions.

Acoustic insertion loss by a bubble layer for the application to air bubble curtain and air masker (기포층 음향 삽입손실 연구: 기포커튼과 에어마스커)

  • Park, Cheolsoo;Jeong, So Won;Kim, Gun Do;Moon, Ilsung;Yim, Geuntae
    • The Journal of the Acoustical Society of Korea
    • /
    • v.39 no.4
    • /
    • pp.227-236
    • /
    • 2020
  • This paper derives the insertion loss for the bubble layer of an air bubble curtain and an air masker which are used to reduce ocean anthropogenic noise such as the piling noise and the ship noise. The air bubble curtain is considered as a 'fluid-air bubble layer-fluid' model and the environment for the air masker is simplified as an 'vacuum-thin plate-fluid-air bubble layer-fluid' model. The air bubble layer in each model is assumed as the effective medium which has the complex wavenumber and the complex impedance corresponding to the bubble population distribution. The numerical simulations are performed to examine the insertion loss depending on the bubble population, the void fraction, and the thickness of the layer.

Effect of Contact Position and Structure of Test Probe on Its Signal Transmission Characteristics (테스트 프로브 접점 위치와 구조의 신호 전달 특성 영향)

  • Lee, Byung-sung;Kim, Moonjung
    • Journal of the Korea Academia-Industrial cooperation Society
    • /
    • v.19 no.10
    • /
    • pp.324-329
    • /
    • 2018
  • This study examined the effects of the contact position and structure of the test probe on its signal transmission characteristics. The contact position in the operating of the test probe was considered and then divided into the plunger inner contact and barrel inlet contact. The high frequency performance of the test probes was investigated for both contact positions. The signal transmission characteristics of the test probes with the structures of double, single, and out-spring was also analyzed. The insertion and return losses were calculated using the HFSS and the characteristic impedance of the test probes was analyzed using a Q3D simulation. The insertion loss of the barrel inlet contact was smaller than that of the plunger inner contact. The contact position of the test probe may result in a change in the high frequency performance. The out-spring probe has better frequency characteristics at -1 dB insertion loss and -10 dB return loss. The double probe and single probe have the same characteristic impedance with $30.8{\Omega}$. On the other hand, the out-spring probe has an impedance of $47.1{\Omega}$. The out-spring probe is closer to $50{\Omega}$ than the other probes and then shows higher signal transmission characteristics. The out-spring probe has superior high-frequency characteristics and is expected to be suitable for high-speed applications.

A Study on Robust Watermarking using HVS Method (인간시각시스템을 이용한 견고한 워터마킹에 관한 연구)

  • Park, Ki-Bum;Lee, Kang-Seung
    • Proceedings of the Korean Information Science Society Conference
    • /
    • /
    • pp.880-882
    • /
    • 2005
  • 본 논문은 디지털 영상 데이터를 대상으로 웨이블릿 변환을 이용하여 주파수 영역에서 워터마크를 삽입하는 블라인드 워터마킹 알고리즘을 제안한다. 각기 다른 다양한 디지털 영상 데이터의 특성을 고려하여 영상의 특성을 반영하는 임계값을 적용하고 가우시안 랜덤 수열(Gaussian Random Sequence)을 워터마크로 삽입하여 원본영상과 워터마킹된 영상이 시각적으로 차이가 없도록 한다. 영상의 특성을 반영하기위한 임계값을 실험을 통하여 조절함으로서 영상의 손실정도, 워터마크 정보의 삽입 양, 검출 상관도 등의 관계를 연구하고 인간의 시각적인 특성을 고려하여 비가시도를 향상하였으며 중주파 대역에 워터마크를 삽입함으로서 원본영상의 손실을 최소화하고 다양한 영상 처리에 견고하도륵 하였다. 제안한 방법의 성능 평가를 위해서 JPEG 손실압축 선형 필터링, 비선형 필터링, 잡음첨가 그리고 크로핑 등의 영상 처리를 실험한 결과 높은 상관도와 견고함을 나타내었고 비가시도 측면에서도 시각적으로 인지할 수 없을 만큼 측정되었다.

  • PDF

Design and fabrication of rectangular waveguide-to-microstrip transition at Ka-band (Ka-band에서의 구형 도파관-마이크로스트립 변환구조의 설계 및 제작에 관한 연구)

  • 정진호;권영우;장영춘;천창율
    • The Journal of Korean Institute of Communications and Information Sciences
    • /
    • v.23 no.7
    • /
    • pp.1770-1776
    • /
    • 1998
  • This paper presents a waveguide-to-mircostrip transition at Ka-band using antipodal finlines. Critical design parameters were identified with the help of theoretical analysis. Experimental optimization was performed together with 3-D FEM analysis in an effort to find optimum dimensions of the transition. In addition to the conventional antipodal finline transition, a new dielectric impedance transformer was introduced to further reduce the insertion loss. Optimized waveguide-to-microstrip transition showed an insertion loss of 0.3~0.4dB/transition at Ka-band. This transition provides superior reproducibility and better performance than conventional coaxcable-to-microstrip transition.

  • PDF