Now showing items 1-20 of 21

  • Adverse wireless communication environment impacts on AF wireless relay networks 

    Lee, Kanghee; Kwon, Hyuck M.; Kim, Deawon; Shim, Yeonggyu; Park, Hyuncheol; Lee, Yong H.; Hyun, Inha (IEEE, 2013)
    This paper proposes amplify-and-forward (AF) relay matrices for a one-source-one-destination pair and cooperative distributed N relay nodes under three adverse wireless relay communication environments: (1) broadband noise ...
  • AF MIMO wireless relay networks under received power constraint 

    Lee, Kanghee; Kwon, Hyuck M.; Kim, Hyunggi; Sawan, M. Edwin; Park, Hyuncheol; Lee, Yong H. (IEEE, 2012-09)
    This paper considers an amplify-and-forward (AF) relay scheme for M-source-M-destination pairs and N relay nodes. Cooperative minimum mean square error (MMSE) strategies for wireless relay networks under both a jamming ...
  • AF wireless relay network analysis under receiver power constraint 

    Lee, Kanghee; Kwon, Hyuck M.; Kim, Hyunggi; Lee, Sangku; Shim, Yeonggyu; Park, Hyuncheol; Lee, Yong H. (IEEE, 2013)
    This paper presents both cooperative and noncooperative amplify-and-forward (AF) relay networks consisting of a one-source-one-destination pair and N-relays under receiver power constraint (RPC) at the destination. The ...
  • Centralized two-way AF MIMO multiple dispersed relay network 

    Lee, Kanghee; Yang, Jie; Kwon, Hyuck M.; Park, Hyuncheol; Lee, Yong H. (IEEE, 2015-05-12)
    This paper considers a two-way amplify-and-forward (AF) multiple-input multiple-output (MIMO) relay network consisting of two sources (each with multiple antennas) and multiple physically dispersed single-antenna relays. ...
  • Closed form of optimum cooperative distributed relay amplifying matrix 

    Lee, Kanghee; Yang, Jie; Kwon, Hyuck M.; Park, Hyuncheol; Lee, Yong H. (IEEE, 2014-05)
    This paper presents a closed form of an optimal cooperative amplify-and-forward (AF) relay amplifying matrix for a distributed relay network of M-source-M-destination pairs and N relays, called a cooperative distributed ...
  • Cooperative AF MIMO wireless relay networks under relay power constraint 

    Lee, Kanghee; Kwon, Hyuck M.; Kim, Hyunggi; Park, Hyuncheol; Lee, Yong H. (IEEE, 2012-11)
    This paper presents an amplify-and-forward (AF) relay scheme for M-source-M-destination pairs and N relay nodes. Cooperative minimum mean square error (MMSE) and zero-forcing (ZF) strategies for wireless relay networks ...
  • Cooperative AF wireless relay strategy under relay power constraint 

    Lee, Kanghee; Kwon, Hyuck M.; Sawan, M. Edwin; Park, Hyuncheol (IEEE, 2013-11)
    This paper presents an optimal relay amplifying matrix based on various schemes, such as zero-forcing (ZF) and minimum mean square error (MMSE), for a cooperative amplify-and-forward (AF) wireless relay network consisting ...
  • Design of millimeter wave hybrid beamforming systems 

    Kwon, Girim; Shim, Yeonggyu; Park, Hyuncheol; Kwon, Hyuck M. (IEEE, 2014-09-14)
    Millimeter wave (mmWave) signals experience a significant path-loss in free space. To overcome this weakness, a large number of antennas are needed to obtain a high beamforming gain. Although a large number of antennas can ...
  • Distributed AF beamforming relay networks under transmit power constraint 

    Lee, Kanghee; Kwon, Hyuck M.; Sawan, M. Edwin; Park, Hyuncheol (IEEE, 2013-11)
    This paper investigates minimum mean square error (MMSE)-based amplify-and-forward (AF) relay amplifying matrices and source/destination beamforming vectors under perfectly known channel state information by imposing ...
  • Distributed AF mobile relay networks in adverse wireless communication environments 

    Lee, Kanghee; Kwon, Hyuck M.; Yang, Jie; Sawan, M. Edwin; Park, Hyuncheol; Lee, Yong H. (IEEE, 2013)
    This paper addresses a more practical relay network consisting of a mobile source, multiple distributed mobile amplify-and-forward (AF) relays, and a mobile destination node. It considers an appropriate channel model between ...
  • The effect of void on characteristics of LDMOS power amplifier 

    Son, Mi-Hyun; Bae, Sooho; Park, Hyuncheol; Kwon, Hyuck M. (Wiley Periodicals, Inc., 2016-03)
    The effect of void on characteristics of the laterally diffused metal oxide semiconductor (LDMOS) power amplifier (PA) is analyzed using the thermal and circuit analysis together. Thermal analysis is performed for finding ...
  • MMSE relaying strategies under jamming, channel uncertainty, node geometry, and power constraint 

    Lee, Kanghee; Kwon, Hyuck M.; Yang, Jie; Sawan, M. Edwin; Park, Hyuncheol; Lee, Yong H. (IEEE, 2013)
    An amplify-and-forward (AF) relay network has been studied extensively, but a closed form of an optimal AF relaying matrix is not available yet for the distributed AF relay network with the destination power constraint ...
  • MMSE relaying strategy for two-way amplify-and-forward wireless networks 

    Lee, Kanghee; Kwon, Hyuck M.; Yang, Jie; Sawan, M. Edwin; Park, Hyuncheol; Lee, Yong H. (IEEE, 2013)
    This paper studies amplify-and-forward (AF) relay strategies for two-way wireless relay networks consisting of two sources with a single antenna and multiple relays with a single antenna. The closed form of relay amplifying ...
  • MMSE-based optimal design of full-duplex relay system 

    Lee, Kanghee; Kwon, Hyuck M.; Jo, Mansik; Park, Hyuncheol; Lee, Yong H. (IEEE, 2012-09)
    This paper studies minimum mean square error (MMSE)-based full-duplex relay processing matrices and source/destination beamforming vectors under perfect channel state information by imposing constraints on the transmit ...
  • Optimal amplify-and-forward precode and relay amplifying matrices 

    Kim, Hyunggi; Kwon, Hyuck M.; Lee, Kanghee; Shim, Yeonggyu; Park, Hyuncheol; Lee, Yong H. (IEEE, 2013)
    A cooperative amplify-and-forward (AF) wireless relay scheme consisting of M sources, N relays, and L destinations all equipped with a single antenna is studied in this paper. The main objective is to design jointly and ...
  • Optimum clustered pilot sequence for OFDM systems under rapidly time-varying channel 

    Kim, Kwanghoon; Park, Hyuncheol; Kwon, Hyuck M. (IEEE, 2012-05)
    As channel time-variation increases, orthogonality among subcarriers in an orthogonal frequency division multiplexing (OFDM) symbol can be destroyed because of the relatively long symbol period, whereupon intercarrier ...
  • PHY-supported frame aggregation for wireless local area networks 

    Shin, Cheolkyu; Park, Hyuncheol; Kwon, Hyuck M. (IEEE, 2014-10)
    An aggregate medium access control (MAC) service data unit (A-MSDU) contains multiple subframes with a single sequence number. Hence, it has a major drawback in environments with high error rates because if any subframes ...
  • Power allocation for AF relaying network under channel phase misalignment 

    Lee, Kanghee; Kwon, Hyuck M.; Yang, Jie; Sawan, M. Edwin; Park, Hyuncheol; Lee, Yong H. (IEEE, 2013)
    This paper studies both cooperative and noncooperative amplify-and-forward (AF) wireless relay strategies with power constraints at the source and at the relays. The main objective is to design jointly and iteratively the ...
  • Selection of amplify-and-forward mobile relay under cascaded Rayleigh fading 

    Lee, Kanghee; Kwon, Hyuck M.; Sawan, M. Edwin; Shim, Yeonggyu; Park, Hyuncheol; Lee, Yong H. (IEEE, 2013)
    This paper assumes a practical channel model, called a cascaded Rayleigh fading channel, for a noncooperative distributed mobile relay network, which consists of one mobile source and one mobile destination, and multiple ...
  • Two-level MMSE relay strategy for an AF wireless relay network 

    Lee, Kanghee; Kwon, Hyuck M.; Xiong, Wenhao; Kim, Hyunggi; Feng, Shuang; Park, Hyuncheol; Lee, Yong H. (IEEE, 2012-10-01)
    This paper presents optimal amplify-and-forward (AF) relay amplifying matrices based on the minimum mean square error (MMSE) criterion for a cooperative AF wireless relay network consisting of a one-source-one-destination ...