• Title/Summary/Keyword: Multiple Antennas

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Large Area Plasma Characteristics using Internal Linear ICP (Inductively Coupled Plasma) Source for the FPD processing

  • Kim, Kyong-Nam;Lim, Jong-Hyeuk;Yeom, Geun-Young
    • 한국정보디스플레이학회:학술대회논문집
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    • 2006.08a
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    • pp.544-547
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    • 2006
  • In this study, the characteristics of large area internal linear ICP sources of $1,020mm{\times}920mm$ (substrate area is $880mm{\times}660mm$) were investigated using a multiple linear antennas with U-type parallel connection. Using the multiple linear antennas with U-type parallel connection, a high plasma density of $2{\times}10^{11}/cm^3$ and a high power transfer efficiency of about 88% could be obtained at 5kW of RF power and with 20mTorr Ar. A low plasma potential of less than 26V and a low electron temperature of $2.6{\sim}3.2eV$ could be also obtained. The measured plasma uniformity on the substrate size of 4th generation $(880mm{\times}660mm)$ was about 4%, therefore, it is believed that the multiple linear antennas with U-type parallel connection can be successfully applicable to the large area flat panel display processing.

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Successive Interference Cancellation for the Uplink of MC-CDMA Systems with Multiple Receive Antennas

  • Kong, Hyung-Yun
    • Journal of electromagnetic engineering and science
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    • v.9 no.2
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    • pp.61-65
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    • 2009
  • Successive interference cancellation(SIC) for the uplink of MC-CDMA mobile communications systems is an effective method to improve performance. We propose a successive interference cancellation(SIC) technique for the uplink of MC-CDMA mobile systems with multiple receive antennas. The destination uses optimum combining(OC) to combine the signals from an OFDM Demodulator with multiple receiving antennas, and applies SIC processing to the combined signals. Achieved interference cancellation order is depends on the signal to interference-plus-noise ratio (SINR) at the output of the optimum combiner. Monte-Carlo simulations are employed to verify the proposed technique.

Performance Comparison of Acquisition Schemes Using Multiple Antennas in DS-CDMA System) (DS-CDMA 시스템에서 다중 안테나를 이용한 동기획득방식의 성능비교)

  • Kang, Bub-Joo
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.29 no.9A
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    • pp.1058-1066
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    • 2004
  • This paper proposes the acquisition system using the multiple antennas in DS-CDMA system. The conventional acquisition schemes using multiple antennas are the methods to utilize the multi-antenna combining and the fixed multi-beam forming of a serial acquisition. Then, this paper proposes the hybrid acquisition scheme using the fixed multi-beam forming. The numerical results show the performance comparison of two acquisition schemes in terms of the acquisition time ill the multipath Rayleigh fading channel.

Optimal Numbers of Base Station Antennas and Users in Multiuser Massive MIMO Systems with Pilot Overhead (다중 사용자 Massive MIMO 시스템의 파일럿 오버헤드를 고려한 최적 기지국 안테나 수 및 사용자 수 분석)

  • Jung, Minchae;Choi, Sooyong
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.41 no.11
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    • pp.1630-1638
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    • 2016
  • In this paper, we consider multiuser massive multiple-input and multiple-output (MIMO) system where multiusers simultaneously utilize massive antennas of base station (BS). With a downlink frame structure considering pilot signals, we derive the ergodic cell capacity based on zero-forcing beamforming (ZFBF) technique. This paper proves that the ergodic cell capacity is concave function with respect to the numbers of BS antennas and users, and derives the optimum numbers of BS antennas and users maximizing ergodic cell capacity. From the simulation results, it is shown that the derived numbers of BS antennas and users has the optimum value for the maximum ergodic cell capacity, and the ergodic cell capacity with the derived optimum values increases with respect to the transmit SNR(Signal to Noise Ratio).

Effect of Multiple Antennas at a Relay Node on the Performance of Physical-Layer Network Coding in Two-Way Relay Channel (양방향 중계채널에서 중계기 다중안테나가 물리계층네트워크 코딩의 성능에 미치는 영향)

  • Park, Jeonghong;Jung, Bang Chul;Ban, Tae-Won
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.20 no.8
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    • pp.1438-1443
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    • 2016
  • In this paper, we investigate the effect of multiple antennas at a relay node on the performance of physical-layer network coding (PNC) in the two-way relay channel (TWRC). We assume that two source nodes have a single antenna and the relay node has multiple antennas. We extend the conventional TWRC environment with a signle antenna at both relay and source nodes to the case of multiple antennas at the relay node. In particular, we consider two decoding strategies: separate decoding (SD) and direct decoding (DD). The SD decodes each packet from the two sources and performs the network coding with bit-wise exclusive OR (XOR) operation, while the DD decodes the network-coded packet from the two sources. Note that both decoding strategies are based on log-likelihood ratio (LLR) computation. It is shown that the bit error rate (BER) performance becomes significantly improved as the number of antennas at the relay node.

A Spectrally Efficient Relaying Scheme with Multiple Antennas for Next-Generation Cellular Networks (차세대 이동통신 망을 위한 다중안테나 기반의 주파수 효율적 데이터 중계 방식)

  • Jung, Bang-Chul;Kang, Min-Seok;Lee, Sang-Wook;Jeon, Seong-Geun
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.15 no.8
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    • pp.1675-1686
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    • 2011
  • We propose a spectrally efficient relaying scheme with multiple antennas for cellular networks which consist of base station (BS), relay station (RSs), and mobile stations (MSs). In general, a BS has more antennas than an RS or an MS. By using multiple antennas, a BS can support another MS with the same frequency resource, where an RS transmits data to a specific MS. In this case, the MS receiving data form an RS also receives the interference form the BS because the BS also uses the same frequency resource at the same time. In this paper, we propose ing and pre-whitening techniques as a pre-coding scheme at the BS for reducing the interference at the MS receiving data from the RS.

A Low-Complexity ML Detector for Generalized Spatial Modulation Based on Priority (GSM을 위한 우선순위 기반 저복잡도 ML 검출 기법)

  • Lee, Man Hee;Shin, Soo Young
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.42 no.4
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    • pp.731-738
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    • 2017
  • In this paper, we proposed a modified ML detector for generalized spatial modulation which is a method among Multiple-input Multiple-output. This proposed method detects signal applying modified channel statement information based on priority. Complexity in conventional methods increases as increasing the number of active antennas. To solve this problem, we proposed a new ML method using static channel information decided by the number of transmit antennas and the number of receive antennas. This method detects active antennas one by one through priority. The proposed method has proved benefit on complexity compared with conventional method through simulations. When the number of transmit antennas is equal to 10, there is approximately 45% complexity reduction.

Low-complexity implementation of OFDMA timing delay detector with multiple receive antennas for broadband wireless access (광대역 무선 액세스를 위한 다중 수신안테나를 갖는 OFDMA 시스템의 낮은 복잡도의 타이밍 딜레이 추정기 구현)

  • Won, Hui-Chul
    • Journal of Korea Society of Industrial Information Systems
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    • v.12 no.3
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    • pp.19-30
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    • 2007
  • In this paper, we propose low-complexity implementation of orthogonal frequency division multiple access (OFDMA) timing delay detector with multiple receive antennas for broadband wireless access (BWA). First, in order to reduce the computational complexity, the detection structure which rotates the phase of the received ranging symbols is introduced. Second, we propose the detection structure with the N-point/M-interval fast Fourier transform structure and a frequency-domain average-power estimator for complexity reduction without sacrificing the system performance. Finally, simulation results for the proposed structures and complexity comparison of the existing structure with the proposed detectors are presented.

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Multi-User Transmission Exploiting Multiple Dual-Polarized Antennas (이중 편파 다중 안테나를 이용한 다중 사용자 전송)

  • Shin, Changyong;Park, Youn Ok
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.39A no.12
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    • pp.774-776
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    • 2014
  • In this paper, we propose a multiple dual-polarized antenna system for multi-user transmission in line-of-sight (LoS) dominant channel environments. By exploiting space and polarization resources efficiently, the proposed system achieves a higher sum rate than the existing multi-user multiple input multiple output (MU-MIMO) system with uni-polarized antennas.

Isolated Power Supply for Multiple Gate Drivers using Wireless Power Transfer System with Single-Antenna Receiver

  • Lim, Chang-Jong;Park, Shihong
    • Journal of Power Electronics
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    • v.17 no.5
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    • pp.1382-1390
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    • 2017
  • This paper presents a power supply for gate drivers, which uses a magnetic resonance wireless power transfer system. Unlike other methods where multiple antennas are used to supply power for the gate drivers, the proposed method uses a single antenna in an insulated receiver to make multiple mutually isolated power supplies. The power transmitted via single antenna is distributed to multiple power supplies for gate drivers through resonant capacitors connected in parallel that also block DC bias. This approach has many advantages over other methods, where each gate driver needs to be supplied with power using multiple receiver antennas. The proposed method will therefore lead to a reduction in production costs and circuit area. Because the proposed circuit uses a high resonance frequency of 6.78 MHz, it is possible to implement a transmitter and a receiver using a small-sized spiral printed-circuit-board-type antenna. This paper used a single phase-leg circuit configuration to experimentally verify the performance characteristics of the proposed method.