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K.j.r. Liu - One of the best experts on this subject based on the ideXlab platform.

  • Systematic space-time trellis Code Construction for correlated Rayleigh-fading channels
    IEEE Transactions on Information Theory, 2004
    Co-Authors: Zoltan Safar, K.j.r. Liu
    Abstract:

    The potential for capacity increase in multiple-antenna wireless communication systems has drawn considerable attention to space-time Codes. However, most of the existing space-time Code Construction methods have assumed ideal channel models: either quasi-static fading or fast fading. In this work, we propose a systematic space-time trellis Code Construction method for correlated fading channels. We derive the performance criteria that take into account both spatial and temporal channel correlation, assuming that the space-time correlation matrix is of full rank. Moreover, we introduce a new design criterion and analyze the properties of the space-time trellis Codes satisfying the proposed criterion. Using the design criterion, we develop a Code Construction procedure that jointly considers diversity advantage and coding advantage for an arbitrary number of transmit antennas and any memoryless modulation. The flexibility of the proposed Code Construction method is demonstrated by designing space-time trellis Codes for two, three, and four transmit antennas with quaternary phase-shift keying (QPSK), 8PSK (phase-shift keying), and 4ASK (amplitude-shift keying) modulations. The simulation results demonstrate that not only can our method generate new Codes for an arbitrary number of antennas, but in some special cases, where previously proposed Codes exist, our Codes also perform very well.

  • ICC - Space-time trellis Code Construction for fast fading channels
    2002 IEEE International Conference on Communications. Conference Proceedings. ICC 2002 (Cat. No.02CH37333), 2002
    Co-Authors: Zoltan Safar, K.j.r. Liu
    Abstract:

    The need for bandwidth- and power-efficient wireless communication systems has raised considerable interest in space-time Codes. In this work, we propose a systematic space-time Code Construction procedure for fast fading channels. The method can be used to design space-time Codes for an arbitrary number of transmit antennas and any memoryless modulation. We introduce a new design criterion that ensures full spatial diversity and develop the Code design method based on this criterion. The flexibility of the proposed approach is demonstrated by designing space-time trellis Codes for 2, 3 and 4 transmit antennas with QPSK, 8PSK and 4ASK modulations.

Zoltan Safar - One of the best experts on this subject based on the ideXlab platform.

  • Systematic space-time trellis Code Construction for correlated Rayleigh-fading channels
    IEEE Transactions on Information Theory, 2004
    Co-Authors: Zoltan Safar, K.j.r. Liu
    Abstract:

    The potential for capacity increase in multiple-antenna wireless communication systems has drawn considerable attention to space-time Codes. However, most of the existing space-time Code Construction methods have assumed ideal channel models: either quasi-static fading or fast fading. In this work, we propose a systematic space-time trellis Code Construction method for correlated fading channels. We derive the performance criteria that take into account both spatial and temporal channel correlation, assuming that the space-time correlation matrix is of full rank. Moreover, we introduce a new design criterion and analyze the properties of the space-time trellis Codes satisfying the proposed criterion. Using the design criterion, we develop a Code Construction procedure that jointly considers diversity advantage and coding advantage for an arbitrary number of transmit antennas and any memoryless modulation. The flexibility of the proposed Code Construction method is demonstrated by designing space-time trellis Codes for two, three, and four transmit antennas with quaternary phase-shift keying (QPSK), 8PSK (phase-shift keying), and 4ASK (amplitude-shift keying) modulations. The simulation results demonstrate that not only can our method generate new Codes for an arbitrary number of antennas, but in some special cases, where previously proposed Codes exist, our Codes also perform very well.

  • ICC - Space-time trellis Code Construction for fast fading channels
    2002 IEEE International Conference on Communications. Conference Proceedings. ICC 2002 (Cat. No.02CH37333), 2002
    Co-Authors: Zoltan Safar, K.j.r. Liu
    Abstract:

    The need for bandwidth- and power-efficient wireless communication systems has raised considerable interest in space-time Codes. In this work, we propose a systematic space-time Code Construction procedure for fast fading channels. The method can be used to design space-time Codes for an arbitrary number of transmit antennas and any memoryless modulation. We introduce a new design criterion that ensures full spatial diversity and develop the Code design method based on this criterion. The flexibility of the proposed approach is demonstrated by designing space-time trellis Codes for 2, 3 and 4 transmit antennas with QPSK, 8PSK and 4ASK modulations.

Jorg Kliewer - One of the best experts on this subject based on the ideXlab platform.

  • an efficient variable length Code Construction for iterative source channel decoding
    IEEE Transactions on Communications, 2009
    Co-Authors: Ragnar Thobaben, Jorg Kliewer
    Abstract:

    We present a novel variable-length Code (VLC) Construction which exhibits an inherent error correcting capability due to the exclusive presence of Codewords with even Hamming weight. Besides error robustness, the proposed Code Construction features a similar Codeword length distribution as Golomb-Rice Codes, and therefore, in particular for sources with exponentially distributed symbols, has good source compression properties at the same time. We show that in a source channel coding framework with outer source encoding, inner channel encoding with a recursive convolutional Code, and iterative decoding the proposed VLC Construction can lead to significant performance improvements compared to fixed-length source encoding with optimized mappings. In particular, simulation results for the AWGN channel verify that for Gauss-Markov sources a performance close to the theoretical limit can be achieved.

Ludo Tolhuizen - One of the best experts on this subject based on the ideXlab platform.

  • polynomial time algorithms for network Code Construction
    IEEE Transactions on Information Theory, 2005
    Co-Authors: Sidharth Jaggi, Peter Sanders, Philip A Chou, Michelle Effros, Sebastian Egner, Kamal Jain, Ludo Tolhuizen
    Abstract:

    The famous max-flow min-cut theorem states that a source node can send information through a network (V,E) to a sink node at a rate determined by the min-cut separating s and t. Recently, it has been shown that this rate can also be achieved for multicasting to several sinks provided that the intermediate nodes are allowed to re-enCode the information they receive. We demonstrate examples of networks where the achievable rates obtained by coding at intermediate nodes are arbitrarily larger than if coding is not allowed. We give deterministic polynomial time algorithms and even faster randomized algorithms for designing linear Codes for directed acyclic graphs with edges of unit capacity. We extend these algorithms to integer capacities and to Codes that are tolerant to edge failures.

  • polynomial time algorithms for multicast network Code Construction
    IEEE Transactions on Information Theory, 2005
    Co-Authors: Sidharth Jaggi, Peter Sanders, Philip A Chou, Michelle Effros, Sebastian Egner, Kamal Jain, Ludo Tolhuizen
    Abstract:

    The famous max-flow min-cut theorem states that a source node s can send information through a network (V, E) to a sink node t at a rate determined by the min-cut separating s and t. Recently, it has been shown that this rate can also be achieved for multicasting to several sinks provided that the intermediate nodes are allowed to re-enCode the information they receive. We demonstrate examples of networks where the achievable rates obtained by coding at intermediate nodes are arbitrarily larger than if coding is not allowed. We give deterministic polynomial time algorithms and even faster randomized algorithms for designing linear Codes for directed acyclic graphs with edges of unit capacity. We extend these algorithms to integer capacities and to Codes that are tolerant to edge failures.

Pavel Rybin - One of the best experts on this subject based on the ideXlab platform.

  • signal Code Construction based on interleaved reed solomon Codes for multiple access system over vector disjunctive channel
    International Conference on Communications, 2018
    Co-Authors: Fedor Ivanov, Pavel Rybin
    Abstract:

    We consider a signal-Code Construction for a special class of multiple access system over vector-disjunctive channel when users transmit some vector of bits of finite length L. This Construction is based on interleaved Reed-Solomon Codes with collaborative decoding. The considered methods of encoding and decoding in one hand have acceptable complexity for a wide range parameters and in other one a decoding algorithm is able to correct significantly more collisions than bounded- distance deCoder. We present some simulation results for relative sum-rate of interleaved Reed- Solomon and for frame error rate (FER) in the case of different number of active users and different Code Constructions. Simulation results we obtained allow us to conclude that our scheme has a good performance even for very short Codes.

  • ISITA - Novel Signal-Code Construction for Multiple Access System over Vector-Disjunctive Channel
    2018 International Symposium on Information Theory and Its Applications (ISITA), 2018
    Co-Authors: Fedor Ivanov, Pavel Rybin
    Abstract:

    Abstract—We consider a new signal-Code Construction for a special class of multiple access system over vector-disjunctive channel when users transmit some vector of bits of finite length L. We propose a special encoding and decoding algorithms for such transmission scenario. Our suggested methods of encoding and decoding on one hand have acceptable complexity for a wide range parameters and on other one a decoding rule we considered has a performance very close to maximum likelihood (ML) decoding. We present some simulation results for relative sum-rate of our Construction and for frame error rate (FER) in the case of different number of active users and different Code Constructions. Simulation results we obtained allow us to conclude that our scheme has a good performance even for very short Codes.

  • ICC Workshops - Signal-Code Construction Based on Interleaved Reed-Solomon Codes for Multiple Access System over Vector-Disjunctive Channel
    2018 IEEE International Conference on Communications Workshops (ICC Workshops), 2018
    Co-Authors: Fedor Ivanov, Pavel Rybin
    Abstract:

    We consider a signal-Code Construction for a special class of multiple access system over vector-disjunctive channel when users transmit some vector of bits of finite length L. This Construction is based on interleaved Reed-Solomon Codes with collaborative decoding. The considered methods of encoding and decoding in one hand have acceptable complexity for a wide range parameters and in other one a decoding algorithm is able to correct significantly more collisions than bounded- distance deCoder. We present some simulation results for relative sum-rate of interleaved Reed- Solomon and for frame error rate (FER) in the case of different number of active users and different Code Constructions. Simulation results we obtained allow us to conclude that our scheme has a good performance even for very short Codes.

  • BlackSeaCom - On the Maximal Achievable Rate for Signal-Code Construction Based on Interleaved Reed-Solomon Codes for Multiple Access System Over Vector-Disjunctive Channel
    2018 IEEE International Black Sea Conference on Communications and Networking (BlackSeaCom), 2018
    Co-Authors: Fedor Ivanov, Pavel Rybin
    Abstract:

    We consider a signal-Code Construction for a special class of multiple access system over vector-disjunctive channel. This Construction is based on interleaved Reed-Solomon Codes with collaborative decoding. The considered methods of encoding and decoding on one hand have acceptable complexity for a wide range parameters and on other one a decoding algorithm is able to correct significantly more collisions than bounded-distance deCoder. We estimate a maximum achievable relative sum-rate of this Construction for fixed number of active users and total number of frequencies to transmit.