• Title, Summary, Keyword: 슬롯

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Design at Small Triangular Slottes Patch Antenna (슬롯에 의한 소형 삼각형 패치 안테나 설계)

  • Hyun, Jae-Sung;Son, Tae-Ho
    • Proceedings of the KAIS Fall Conference
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    • pp.377-380
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    • 2006
  • 본 논문에서는 USPCS 기지국 송신밴드 (주파수 대역 $1.93\;Ghz^{\sim}1.99\;Ghz$)에 만족하는 소형이면서도 대역폭이 넓은 슬롯 삼각형 패치 안테나를 설계 및 제작하였다. 각각의 슬롯의 길이와 폭을 변화시켰을 때의 입력반사계수의 특성을 고찰하였고, 슬롯이 있을 때와 없을 때의 패치 안테나의 크기를 비교하였다. 그 결과 슬롯에 의해 크기를 줄일 수 있을 뿐만 아니라 대역폭도 넓힐 수 있음을 확인하였다.

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Compact Slot Antenna Fed by T-shaped Microstrip (T형 마이크로스트립으로 급전된 소형 슬롯안테나)

  • Kim, Gun-Kyun;Lee, Jong-Ig
    • Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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    • pp.576-579
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    • 2007
  • 마이크로스트립으로 급전되는 슬롯 안테나를 소형화하기 위해 폴디드 슬롯과 T형 마이크로스트립 선로로 구성된 안테나 구조를 제안하였다. 전형적인 마이크로스트립으로 급전된 슬롯 안테나와 성능(안테나 크기, 슬롯 길이, 대역폭 등)을 비교하였으며, T형 마이크로스트립선로를 이용한 급전선로의 임피던스정합 방법에 대하여 설명하였다. 제안된 구조로 유전제기판상에 2.45GHz 대역 WLAN용 안테나를 설계 및 제작하였으며 특성 실험(반사손실, 부사패턴)을 통해 연구의 타당성을 확인하였다.

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Protocol supporting Variable-length Message using Reservation Slots in WDM Local Network (WDM Local Network에서 예약슬롯을 이용한 가변길이 메시지 지원 프로토콜)

  • 진교홍
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.5 no.2
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    • pp.257-262
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    • 2001
  • A new WDM-based protocol for scheduling a variable-length message is proposed in this paper Two control channels, reservation slot and control slot, are used to coordinate transmission and diminish the collisions of packet to minimize the across delay. When an idle control slot is available, control packet is transmitted on that slot and message is transferred. And the node continues to transmit its control packet through the corresponding slot every cycle, until the message is completely transmitted. If any control slot is not available, the node schedules the transmission time of message in earliest available time using reservation slots. The proposed scheduling algorithm shows better performance and lower access delay.

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A Channel Access Control algorithm and a Dynamic Slot Allocation algorithm for rt_VBR services and ABR services in Wireless ATM Networks (무선 ATM망에서 rt_VBR 및 ABR 서비스를 위한 채널 접속 제어 알고리즘과 동적 대역 할당 알고리즘)

  • Yang, Seong-Ryoung;Im, In-Taek;Heo, Jeong-Seok
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.28 no.3B
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    • pp.191-199
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    • 2003
  • In this paper, a channel access control algorithm and a dynamic slot allocation algorithm are proposed for rt_VBR services and ABR services in the wireless ATM networks. In the proposed algorithm, rt_VBR terminals that require real-time services transmit a reservation request packet by a RAS minislot. An rt_VBR terminal, which transmitted the reservation request packet, transmits the dynamic parameters by DPS minislot without contention. On the other hand, ABR terminals that have a non-real-time traffic burst transfer a reservation request packet with contention basis. Based on the received dynamic parameters, the base station scheduler allocates uplink data slots as well as DPS minislot into rt_VBR terminals.

Design and Fabrication of the Hybrid Slot Antenna for Wireless LAN at 5.8㎓ Band (5.8㎓ 대역 무선 LAN용 하이브리드 슬롯 안테나 설계 및 제작)

  • 고수미;이권익;김흥수
    • Journal of the Institute of Electronics Engineers of Korea TC
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    • v.39 no.10
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    • pp.21-26
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    • 2002
  • In this paper, a hybrid slot antenna is designed and fabricated for wireless LAN at 5.8㎓ band. The hybrid slot antenna is consisted of the inductively-fed slot and capacitively-fed slot. To obtain wide bandwidth, the inductively-fed slot is designed at 5.3㎓ and the capacitively-fed slot is designed at 5.8㎓ Important parameters in the design are slot width and CPW length. The hybrid slot antenna is simulated by using Ensemble 6.0. The measured results of this antenna are compared with its simulated results. The resonant frequency of fabricated hybrid slot antenna is 5.8㎓, the bandwidth for VSWR<1.5 is 28% and the gain is 5 ㏈i. The 3-㏈ beamwidths in E-plane and H-plane are 60°and 44°, respectively.

Cipher method of digital voice data using fixed time slot mode in PCM system (고정 타임슬롯 모드를 사용하는 PCM 시스템에서 디지털 음성 데이터 보안 기법)

  • Im, Sung Yeal
    • Proceedings of the Korea Information Processing Society Conference
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    • pp.782-785
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    • 2010
  • 본 논문은 연속된 음성 신호를 전송로 상에 전송하기 위해 음성 신호를 G.711 표준 권고인 PCM으로 다중화한 후 고정 타임슬롯을 배정하여 전송하는 시스템에서 PCM 화된 디지털 음성 데이터를 실시간으로 암호화하여 전송하는 스트림 암호화 기법에 관한 것이다. 실시간으로 처리되는 음성 데이터의 암호화 시에는 하드웨어 방식이 적합한 데, 본 논문에서는 고정 타임슬롯을 배정받는 음성 데이터의 실시간 암호화 기법에 관한 것이다. 일반적으로 아날로그 음성 신호 코딩 시에 국내에서는 북미 방식인 ${\mu}-law$ 코딩 기법을 적용하는 데 이는 표본화한 음성 데이터를 양자화전에 압축하고 복호화 후 신장하는 비선형 양자화 기법을 적용하는 것으로 표본화된 값을 8 비트의 PCM 데이터로 변화하여 E1(2.048Mbps) 급 속도로 전송한다. 본 논문에서는 PCM 전송로 상에 전송되기 전의 직렬 입력 데이터를 암호화 장치를 거쳐 해당 타임슬롯에 해당하는 8 비트의 데이터를 실시간으로 암호화하여 전송로 상으로 전송하고 역으로 수신 단에서는 PCM 전송로를 거친 직렬 입력 데이터를 암호화된 타임슬롯을 판별하여 해당 타임슬롯의 데이터를 복호화하여 원래 데이터를 복원한다. 본 논문에서는 고정 타임슬롯을 배정받은 PCM 데이터를 암호화하여 전송한 후 수신 단에서 복호화 과정을 거친 후 타임슬롯 단위로 데이터 암호화/복호화가 가능함을 보여준다.

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Dynamic Slot Re-assignment Scheme for Network Merge in Swarming Drone Networks (군집 드론 네트워크에서 네트워크 결합을 위한 동적 슬롯 재할당 기법)

  • Lee, Jong-Kwan;Lee, Minwoo
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.23 no.2
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    • pp.156-164
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    • 2019
  • In this paper, we propose an efficient dynamic slot re-assignment scheme for swarming drone networks in which networks members merged and split frequently. The leader drone of each network recognizes the slot allocation information of neighbor networks by periodic information exchange among between the drones. Using the information, the leader drone makes a decision how to reallocate the slots between members in case of network merge. The non-competitive method in the proposed scheme can re-assign the slots without any slot collision and shows always superior performance than competitive scheme. The competitive method in the proposed scheme reduces the number of slots that should be re-assigned in case of network merge. The experimental performance analysis shows that the proposed scheme performs better or at least equal to the performance of the competitive scheme in a swarming drone network.

Performance Enhancement of Slot-Count Selection Algorithm with Weight Differentiation in Gen-2 RFID Systems (Gen-2 RFID 시스템에서 가중치 차별화를 통한 슬롯 카운트 선택 알고리즘의 성능 향상)

  • Lim, In-Taek
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.15 no.3
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    • pp.561-566
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    • 2011
  • In EPCglobal Class-1 Gen-2 RFID system, a slot-count selection algorithm has been proposed to determine the slot-count size depending on the status of reply slot. In the slot-count selection algorithm of Gen-2, the slot-count value is increased or decreased by the weight C, which is identical and independent of the slot status. It has an advantage that the algorithm is simple, but it is difficult to maintain an optimal slot-count size. Therefore, in this paper, we propose an adaptive slot-count selection algorithm, which applies the parameter C differently based on the result of tag replies. Through simulations, it is demonstrated that the collision rate for the proposed scheme is about 42% and 65% lower than the schemes proposed by Wang and Gen-2. Therefore, the adaptive slot-count selection algorithm achieves faster tag identification time compared with the existing algorithms due to the low collision rate.

A Study on the Efficient Extraction of Slot Admittance for the Design of a Non-Resonant Waveguide Edge Slot Array (비공진형 협벽 도파관 슬롯 배열 설계를 위한 효율적인 슬릇 어드미턴스 추출 방법에 관한 연구)

  • Park, Jong-Kuk;Han, Ki-Jin;Na, Hyung-Gi;Kim, Chan-Hong;Lee, Dong-Kook
    • The Journal of Korean Institute of Electromagnetic Engineering and Science
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    • v.19 no.11
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    • pp.1223-1232
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    • 2008
  • In this paper, an analytic method is proposed to extract the reference slot admittance required for the design of a non-resonant waveguide edge slot array. A slot and two neighboring transmission line sections of the numerous alternately inclined slots with the identical inclination angle are modelled as a uniform lossy transmission line, and thus, the total ABCD matrix is easily calculated and compared with the simulated or measured one. From this procedure, the complex characteristic impedance and the complex propagation constant of the lossy transmission line are calculated and the normalized slot admittance is analytically obtained. In order to validate the proposed method, the admittance value of a reference slotted waveguide fabricated for designing the X-band edge slot array is extracted and it is compared with the one obtained by the other conventional method.

Design of Compact CPW-fed Slot Antenna Using Split-Ring Resonators (분할 링 공진기를 이용한 소형 CPW급전 슬롯 안테나 설계)

  • Park, Jin-Taek;Yeo, Junho;Lee, Jong-Ig
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.18 no.10
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    • pp.2351-2358
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    • 2014
  • In this paper, a design method for a compact CPW-fed slot antenna using SRRs is studied. The structure of the proposed slot antenna is a rectangular slot antenna loaded with SRR conductors inside the slot to reduce the antenna size. Optimal design parameters are obtained by analyzing the effects of the gap between the SRR conductors and slot, and the width of the SRR conductors on the input VSWR characteristic. The optimized compact slot antenna operating at 2.45 GHz band is fabricated on an FR4 substrate with a dimension of 36 mm by 30 mm. The length of the proposed compact slot antenna is reduced to 14.3% compared to that of a conventional rectangular slot antenna. Experiment results show that the antenna has a desired impedance characteristic with a frequency band of 2.4-2.49 GHz for a VSWR < 2, and measured gain of 2.3 dBi at 2.45 GHz.