Results 201 to 210 of about 30,726 (232)
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ACM SIGCOMM Computer Communication Review, 2010
OFDMA will be the predominant technology for the air interface of broadband mobile wireless systems for the next decades. In recent years, OFDMA-based networks based on IEEE 802.16, and increasingly also on 3GPP LTE are rolled out for commercial use. This article gives an overview of the main challenges for the deployment and operation of state-of-the ...
Andreas Maeder, Nader Zein
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OFDMA will be the predominant technology for the air interface of broadband mobile wireless systems for the next decades. In recent years, OFDMA-based networks based on IEEE 802.16, and increasingly also on 3GPP LTE are rolled out for commercial use. This article gives an overview of the main challenges for the deployment and operation of state-of-the ...
Andreas Maeder, Nader Zein
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2010
Supported by the expert-level advice of pioneering researchers, Orthogonal Frequency Division Multiple Access Fundamentals and Applications provides a comprehensive and accessible introduction to the foundations and applications of one of the most promising access technologies for current and future wireless networks. It includes authoritative coverage
Wu, J, Xiao, Pei
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Supported by the expert-level advice of pioneering researchers, Orthogonal Frequency Division Multiple Access Fundamentals and Applications provides a comprehensive and accessible introduction to the foundations and applications of one of the most promising access technologies for current and future wireless networks. It includes authoritative coverage
Wu, J, Xiao, Pei
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An Analysis of Uplink OFDMA Optimality
IEEE Transactions on Wireless Communications, 2006Motivated by the increasing popularity of OFDMA, this paper studies the sum-rate optimality of OFDMA as an uplink multicarrier multiple-access scheme. We address the relationship between OFDMA and the optimal multicarrier multiple- access schemes.
null Hongxiang Li, null Hui Liu
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Opportunistic Spectrum Multichannel OFDMA
2007 IEEE International Conference on Communications, 2007Opportunistic Spectrum Access (OSA) is being seriously considered for the future spectrum needs. In this paper we propose a simple and effective multichannel multiple access technique for OSA networks. In our design users of an OSA network must contact the OSA Base Station to gain access to the radio resources.
P. Pawelczak, R. V. Prasad, R. Hekmat
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2006
Abstract In this paper we describe an adaptive method for maximizing the sumrate in the uplink of a multi-user multi-carrier system. Based on theoptimum power allocation, which is computed by the capacity-achievingiterative water-fllling algorithm, we accordingly assign the users to thecorresponding subcarriers.
S. Pfletschinger, F. Bader
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Abstract In this paper we describe an adaptive method for maximizing the sumrate in the uplink of a multi-user multi-carrier system. Based on theoptimum power allocation, which is computed by the capacity-achievingiterative water-fllling algorithm, we accordingly assign the users to thecorresponding subcarriers.
S. Pfletschinger, F. Bader
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Approximability of OFDMA Scheduling
2009In this paper, we study the complexity and approximability of the orthogonal frequency-division multiple-access (OFDMA) scheduling problem with uniformly related communication channels.
Marcel Ochel, Berthold Vöcking
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Coded Cooperation in OFDMA Systems
2006 40th Annual Conference on Information Sciences and Systems, 2006A novel time-frequency cooperative communication strategy is proposed for coded OFDMA system over quasi-static frequency-selective Rayleigh fading. To take advantage of the frequency dispersion, each user transmits his partner's and his own data on different subcarriers spreading over the entire available bandwidth.
Jun Niu, I-tai Lu
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2008
Let us give an overview how wireless technology takes a smooth coarse from singlecarrier to OFDMA to understand the necessity for robust communication and better efficiency.
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Let us give an overview how wireless technology takes a smooth coarse from singlecarrier to OFDMA to understand the necessity for robust communication and better efficiency.
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OFDMA for underwater acoustic communications
2011 49th Annual Allerton Conference on Communication, Control, and Computing (Allerton), 2011We investigate the possibility of using orthogonal frequency division multiple access (OFDMA) for design of efficient underwater acoustic (UWA) networks. The major challenge for the OFDMA-based UWA communication systems is the Doppler-induced frequency scaling, which may cause severe intercarrier interference (ICI), and depending on the particular user
Kai Tu +3 more
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2010
IEEE 802.16 physical (PHY) layer is characterized by Orthogonal Frequency Division Multiplexing (OFDM), Time Division Duplexing, Frequency division Duplexing, Quadrature Amplitude Modulation and Adaptive Antenna Systems. After discussing the basics of OFDM and Orthogonal Frequency division Multiple Access (OFDMA), scalable OFDMA is presented and ...
Ramjee Prasad, Fernando J. Velez
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IEEE 802.16 physical (PHY) layer is characterized by Orthogonal Frequency Division Multiplexing (OFDM), Time Division Duplexing, Frequency division Duplexing, Quadrature Amplitude Modulation and Adaptive Antenna Systems. After discussing the basics of OFDM and Orthogonal Frequency division Multiple Access (OFDMA), scalable OFDMA is presented and ...
Ramjee Prasad, Fernando J. Velez
openaire +1 more source