Results 251 to 260 of about 33,278 (292)
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Codebook Design for MIMO Retransmission System
IEEE Communications Letters, 2011This letter proposes a new retransmission structure with multiple retransmission codebooks for a linear precoding-based closed-loop multiple-input multiple-output (CL-MIMO) system. While conventional codebooks are defined only for the initial transmission in CL-MIMO systems, we propose a multiple codebook structure in which a different codebook is used
Jinwoo Kim, Chung Gu Kang 0001
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Nested codebook design for MIMO precoders
2008 42nd Asilomar Conference on Signals, Systems and Computers, 2008In multi-input, multi-output (MIMO) communication systems, significant throughput gains can be obtained by closed-loop operation, where two aspects of the transmission are adapted to channel conditions: the transmission rank (number of independent spatial layers); and the precoding matrix which maps the spatial layers to the transmit antennas.
Badri Varadarajan +3 more
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2019 9th International Conference on Advances in Computing and Communication (ICACC), 2019
Sparse code multiple access (SCMA) is one of the promising non-orthogonal multiple access which utilizes iterative message passing algorithm (MPA) as decoding technique. This paper discusses about, basics of SCMA, mapping of information to codebooks, codebook structure and functioning of receiver. In SCMA, each user has their own codebook.
J Prabhavathi bhai, K Rama Naidu
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Sparse code multiple access (SCMA) is one of the promising non-orthogonal multiple access which utilizes iterative message passing algorithm (MPA) as decoding technique. This paper discusses about, basics of SCMA, mapping of information to codebooks, codebook structure and functioning of receiver. In SCMA, each user has their own codebook.
J Prabhavathi bhai, K Rama Naidu
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Complex Codebooks From Combinatorial Designs
IEEE Transactions on Information Theory, 2006Codebooks (also called signal sets) meeting the Welch bounds are desirable in code-division multiple-access (CDMA) systems. In 2003, binary codebooks meeting Welch's bounds were constructed using difference sets by Ding, Golin, and Kloslashve. Recently, a generic construction of codebooks with cyclic difference sets meeting Welch's bound on the maximum
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A refinement algorithm for vector quantization codebook design
1998 IEEE International Conference on Electronics, Circuits and Systems. Surfing the Waves of Science and Technology (Cat. No.98EX196), 2002A new algorithm for vector quantization codebook design is presented, which iteratively calls the classical generalized Lloyd algorithm (GLA) and keeps track of the best codebook so far. In our proposed Refine_ GLA the GLA runs are not independent trials, instead, a fraction of the initial codevectors are taken from the best codebook, while the rest ...
Armando Malanda-Trigueros +1 more
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Space-Time Codebook Design for Spread Systems
Wireless Personal Communications, 2012The problem of designing space-time constellations for communication in spread multiple-antenna wireless systems over Rayleigh fading channel is addressed. Using the asymptotic union bound on error probability as design criterion, codes based on general complex-valued symbols are obtained with a gradient search optimization technique.
Marko Beko, Rui Dinis 0001
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Designing optimum mother constellation and codebooks for SCMA
2017 IEEE International Conference on Communications (ICC), 2017Sparse code multiple access (SCMA) is a nonorthogonal codebook based multiple access scheme, proposed to cope with the heterogeneous and challenging performance requirements for mission critical communication and massive machine-type communication in the fifth generation wireless system.
Mehmood Alam, Qi Zhang 0013
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Codebook Design for Massive MIMO Systems in LTE
2016 IEEE 83rd Vehicular Technology Conference (VTC Spring), 2016In this paper, codebook design for massive MIMO systems with 32/64Tx transmit branches is investigated. Using the same parameterized codebook framework of LTE Rel-13 for 16Tx, 32/64Tx codebooks are discussed and evaluated through system level simulations.
Hui Li +5 more
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Design and Evaluation of LTE-Advanced Double Codebook
2011 IEEE 73rd Vehicular Technology Conference (VTC Spring), 2011In this paper we address codebook design for LTE-Advanced downlink. In order to meet the peak spectral efficiency requirements of up to 30 bit/s/Hz, LTE-Advanced supports up to eight transmit antennas in downlink, enabling spatial multiplexing transmissions with up to eight parallel streams.
Shuang Tan +5 more
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SCMA codebook design based on constellation rotation
2017 IEEE International Conference on Communications (ICC), 2017Sparse code multiple access (SCMA) is a competitive non-orthogonal multiple access technique for the fifth generation (5G) wireless communications. The SCMA codebook design is a very essential problem. This paper presents a constellation-rotation-based method for designing codebooks for downlink SCMA system.
Yongkang Zhou +3 more
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