• Title, Summary, Keyword: 슬롯

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Design and Fabrication of Mulitiple U-shaped slot Microstrip Antenna on 5㎓ Application (5㎓ 대역에서 동작하는 다중 U-슬롯 모양의 마이크로스트립 안테나의 설계 및 제작)

  • 윤중한;정계택;이상목;안규철;곽경섭
    • Journal of the Institute of Electronics Engineers of Korea TC
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    • v.40 no.11
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    • pp.85-92
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    • 2003
  • In this paper, a multiple U-shaped slot antenna on 5㎓ band is designed, fabricated, and measured. The prototype consists of a U-shaped slot and two Invert U-shaped slot. To obtain wide bandwidth, the foam layer is inserted between ground plane and substrate. After various parameters, length, width, position of U-shaped slot horizontal, interval length between two invert U-shaped slot, feeding position and airgap width, optimized, a multiple U-shaped slot antenna is fabricated and measured. The measured results of the antenna are compared with its simulated results. A 2:1 VSWR impedance bandwidth of 20.4% is achiedved by employing this technique. The gain is about 5.5㏈i. The experimental far-field patterns are stable across the pass band.

Access Control Protocol for Bursty Traffic in TDMA/TDD-based Wireless ATM Networks (TDMA/TDD 기반 무선 ATM망에서 버스트 트래픽을 위한 접속 제어 프로토콜)

  • 임인택
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.7 no.4
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    • pp.684-690
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    • 2003
  • In this paper, a contention-based reservation access control algorithm and a slot allocation algorithm are proposed for non-real-time bursty traffic services in the wireless ATM networks. In order to reduce the collisions of the reservation request packets, the base station scheduler calculates the transmission probability using the number of RAS minislots and the estimated load of the reservation request packets. And it broadcasts the calculated transmission probability over the downlink control channel. Mobile terminals, which have traffic burst, select randomly a RAS minislot and transmit the reservation request packet by the received transmission probability. The reservation request packet contains the number of packets in the buffer. The slot allocation is based on the buffer status of the received reservation request packets. The base station scheduler allocates slots in proportion to the total number of slots that are requested by each terminal.

A Design of Wideband Printed Dual Meandered Slot Antenna (인쇄회로형 광대역 이중 미앤더드 슬롯 안테나 설계)

  • 이윤경;임계재;이재용;윤현보
    • The Journal of Korean Institute of Electromagnetic Engineering and Science
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    • v.13 no.3
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    • pp.243-250
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    • 2002
  • This paper designed a compact printed meandered scot antenna which to integrate in wireless LAN and proposed a printed dual meandered slot antenna for improving bandwidth. A printed dual meandered slot antenna is calculated by using the mehtod of FDTD. The calculated results showed good agreement with the measured results. As a result of measurement, the bandwidth(VSWR< 2) of single meandered slot antenna is 115 MHz and the bandwidth of dual meandered slot antenna is 164 MHz. The dual meandered slot antenna bandwidth has been improves to that of 43% comparing to single meandered slot antenna.

Gravitational deflection analysis for the shielded slot plate with many tiny structures (미세 구조물이 성형된 쉴드슬롯판의 자중 처짐 해석)

  • Lee S.W.;Shim U.T.;Lee K.S.;Woo D.U.;Kim J.H.
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.7 no.3
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    • pp.291-297
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    • 2006
  • In this study, the equivalent physical properties of the shielded slot plate having a lot of very tiny bridge shape structures on its plane were determined by tensile tests and structural analyses. With those results, numerical analyses for the deflection profile by gravity effect were carried out to compare with experimental results. The two results were shown coincident very well so that the estimated equivalent physical properties were verified enough for further studies such as curvature reduction for the shielded slot plate.

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A Frequency Reconfigurable Slot Antenna with Bandwidth-Enhanced Characteristics (대역폭 확장 특성을 갖는 주파수 Reconfigurable 슬롯 안테나)

  • Lee Woo-Sung;Kim Hyung-Rak;Yoon Young-Joong
    • The Journal of Korean Institute of Electromagnetic Engineering and Science
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    • v.17 no.6
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    • pp.556-561
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    • 2006
  • In this paper, a frequency reconfigurable slot antenna which has a bandwidth-enhanced characteristic is proposed. The proposed antenna consists of two parts; the wide slot and the narrow slot, to increase the bandwidth of the antenna and have the frequency reconfigurable characteristic. The wide slot has triangular shape and makes the bandwidth increased, and the narrow slot can mount PIN diodes. By changing on/off state of PIN diodes, the total length of the slot is changed. From this characteristic, the proposed antenna can finally control the center frequency and minimize variation of the impedance matching.

Computational Study of the Passive Control of the Oblique-Shock-Interaction Flows (경사충격파 간섭유동의 피동제어에 관한 수치해석적 연구)

  • Chang, Sung-Ha;Lee, Yeol;Lee, Yong-Hee
    • Proceedings of the Korean Society of Propulsion Engineers Conference
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    • pp.327-330
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    • 2006
  • Numerical study on the passive control of the oblique shock wave/turbulent boundary-layer interaction control utilizing slotted plates over a cavity has been carried out. Numerical results have been compared with the experimental observations, such as pitot/wall surface pressures and Schlieren flow visualizations, obtained for the same boundary conditions. It was found that the present numerical results shows a good agreement with experimental data. Further, the effect of different slot configurations including various number, location and angle of slots on the characteristics of the interactions are also tested, focusing on the variation of the piot pressure and the boundary-layer characteristics downstream of the interaction and the recirculating mass flux through cavity.

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Design and Performance Evaluation of IR-UWB Tapered Slot Antenna for Optimum Impulse Radio Radiation (임펄스 신호 방사를 위한 IR-UWB용 테이퍼 슬롯 안테나 설계 및 성능평가)

  • Kim, Jong-Min;Koh, Young-Mok;Ra, Keuk-Whan
    • The Journal of The Korea Institute of Intelligent Transport Systems
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    • v.11 no.5
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    • pp.103-115
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    • 2012
  • In this paper, design and performance evaluation of Tapered Slot Antenna for IR-UWB which propagates impulse radio is performed. TSA which has directional characteristic in UWB band should have low radiation loss and minimized impulse radiation distortion. In order to achieve these objectives, the paper designed wide band Impedance transformer and microstrip-slotline transit region structured TSA feeder line. By using the fabricated TSA, the radiation pattern was measured in the radio anechoic chamber. Pulse fidelity and distortion equation was induced to evaluate time domain characteristics according to the impulse radiation. Pulse fidelity of Impulse radiation show favorable results more than 93% within ${\pm}30^{\circ}$ beam width.

Leaky Wave Radiation from Dielectric-Coated Parallel-Plate Waveguied Periodic Slot with Finite Thickness : H-polarization (유전체로 코팅된 유한한 두께의 주기 슬롯을 갖는 평행평판 도파관으로부터 누설파 복사 : H-편파)

  • Kim, Joong-Pyo;Lee, Chang-Won;Son, Hyon
    • The Journal of Korean Institute of Electromagnetic Engineering and Science
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    • v.10 no.2
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    • pp.247-256
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    • 1999
  • The leaky wave emanated from the dielectric-coated parallel-plate waveguide with finite periodic thick slot in its upper plate is investigated theoretically for H-polarization case. For this structure, fields in slot regions are expressed as a summation of the parallel-plate waveguide TM modes, and in other regions are expressed in the spectral domain by use of the inverse Fourier transform. Boundary conditions at the interfaces are enforced, and the simultaneous linear equations are derived. The influences of the slot width, slot thickness, thickness of a dielectric coating, and finite slot number on the radiation characteristics (phase constant, leakage constant, radiation pattern) are examined. The results of the finite periodic slot are compared with those of the infinite extent structure and good agreement has been found.

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Design and Fabrication of a Broadband Microstrip Slot Antenna with a Fork-shaped Feedline (포크모양의 급전선로를 갖는 광대역 마이크로스트립 슬롯 안테나 설계 및 제작)

  • 문영길;김흥수
    • Journal of the Institute of Electronics Engineers of Korea TC
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    • v.41 no.8
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    • pp.87-92
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    • 2004
  • In this paper, a microstrip slot antenna with a fork-shaped feedline is designed and fabricated. To obtain a broadband characteristic of a wide slot antenna a feedline is transformed into a shape of a fork, and a size of the slot and offset - length is varied. As the characteristics of the slot antenna as the function of design parameters are analyzed, a broadband microstrip slot antenna is designed. The microstrip slot antenna with a fork-shaped feedline is fabricated and its measured bandwidth is from 1.65 GHz to 6.20 GHz for VSWR$\leq$2.

Design and Manufacture of X-Band 10 X 10 Waveguide Slot Array Antenna for SAR (SAR용 X-밴드 10 10도파관 슬롯 배열 안테나 설계 및 제작)

  • 신영종;이범선
    • The Journal of Korean Institute of Electromagnetic Engineering and Science
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    • v.15 no.11
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    • pp.1019-1025
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    • 2004
  • The X-band 10${\times}$10 waveguide slot array antenna for SAR is designed, fabricated and measured. The array antenna is designed using the equivalent circuit model based on the field distribution of the dominant mode, TE$\sub$10/, and EM simulation. The method to decide optimum angle of the centered inclined slot(coupling slot) and the optimum of offset of the longitudinal slot(radiating slot) is provided. The designed antenna structure is EM simulated and fabricated. The measured return loss bandwidth is 180 MHz at 9.15 GHz , the side lobe level is below -25 dB, HPBW is about 9$^{\circ}$, and the gain is 25.5 dB. These results are similar to the simulation data.