Access Channel

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Shlomo Shamai - One of the best experts on this subject based on the ideXlab platform.

  • on the sum rate capacity of non symmetric poisson multiple Access Channel
    International Symposium on Information Theory, 2016
    Co-Authors: Ain-ul Aisha, Yingbin Liang, Shlomo Shamai
    Abstract:

    In this paper, we characterize the sum-rate capacity of the non-symmetric Poisson multiple Access Channel (MAC). While the sum-rate capacity of the symmetric Poisson MAC has been characterized in the literature, the special property exploited in the existing method for the symmetric case does not hold for the non-symmetric Channel anymore. We obtain the optimal input that achieves the sum-rate capacity by solving a non-convex optimization problem. We show that, for certain Channel parameters, it is optimal for a single user to transmit to achieve the sum-rate capacity. This is in sharp contrast to the Gaussian MAC, in which all users must transmit, either simultaneously or at different times, in order to achieve the sum-rate capacity.

  • ISIT - On the sum-rate capacity of non-symmetric Poisson multiple Access Channel
    2016 IEEE International Symposium on Information Theory (ISIT), 2016
    Co-Authors: Ain-ul Aisha, Lifeng Lai, Yingbin Liang, Shlomo Shamai
    Abstract:

    In this paper, we characterize the sum-rate capacity of the non-symmetric Poisson multiple Access Channel (MAC). While the sum-rate capacity of the symmetric Poisson MAC has been characterized in the literature, the special property exploited in the existing method for the symmetric case does not hold for the non-symmetric Channel anymore. We obtain the optimal input that achieves the sum-rate capacity by solving a non-convex optimization problem. We show that, for certain Channel parameters, it is optimal for a single user to transmit to achieve the sum-rate capacity. This is in sharp contrast to the Gaussian MAC, in which all users must transmit, either simultaneously or at different times, in order to achieve the sum-rate capacity.

  • shannon theoretic approach to a gaussian cellular multiple Access Channel with fading
    IEEE Transactions on Information Theory, 2000
    Co-Authors: Oren Somekh, Shlomo Shamai
    Abstract:

    Shannon-theoretic limits on the achievable throughput for a simple infinite cellular multiple-Access Channel (MAC) model (Wyner 1994) in the presence of fading are presented. In this model, which is modified to account for flat fading, the received signal, at a given cell-site's antenna, is the sum of the faded signals transmitted from all users within that cell plus an attenuation factor /spl alpha//spl isin/[0,1] times the sum of the faded signals received from the adjacent cells, accompanied by Gaussian additive noise. This model serves as a tractable model providing considerable insight into complex and analytically intractable real-world cellular communications. Both linear and planar cellular arrays are considered with exactly K active users in each cell. We assume a hyper-receiver, jointly decoding all of the users, incorporating the received signals from all of the active cell-sites. The hyper-receiver is assumed to be aware of the codebooks and realizations of the fading processes of all the users in the system. In this work we consider the intracell time-division multiple-Access (TDMA) and the wideband (WB) protocols. We focus on the maximum reliably transmitted equal rate. Bounds to this rate are found for the intracell TDMA protocol by incorporating information-theoretic inequalities and the Chebyshev-Markov moment theory as applied to the limiting distribution of the eigenvalues of a quadratic form of tridiagonal random matrices. We demonstrate our results for the special case where the amplitudes of the fading coefficients are drawn from a Rayleigh distribution, i.e., Rayleigh fading. For this special case, we observe the rather surprising result that fading may increase the maximum equal rate, for a certain range of /spl alpha/ as compared to the nonfaded case. In this setting, the WB strategy, which achieves the maximum reliable equal rate of the model, is proved to be superior to the TDMA scheme. An upper bound to the maximum equal rate of the WB scheme is also obtained. This bound is asymptotically tight when the number of users is large (K/spl Gt/1). The asymptotic bound shows that the maximum equal rate of the WB scheme in the presence of fading is higher than the rate which corresponds to the nonfaded case for any intercell interference factor /spl alpha//spl isin/[0,1] signal-to-noise ratio (SNR) values. This result is found to be independent of the statistics of the fading coefficients.

Ain-ul Aisha - One of the best experts on this subject based on the ideXlab platform.

  • on the sum rate capacity of non symmetric poisson multiple Access Channel
    International Symposium on Information Theory, 2016
    Co-Authors: Ain-ul Aisha, Yingbin Liang, Shlomo Shamai
    Abstract:

    In this paper, we characterize the sum-rate capacity of the non-symmetric Poisson multiple Access Channel (MAC). While the sum-rate capacity of the symmetric Poisson MAC has been characterized in the literature, the special property exploited in the existing method for the symmetric case does not hold for the non-symmetric Channel anymore. We obtain the optimal input that achieves the sum-rate capacity by solving a non-convex optimization problem. We show that, for certain Channel parameters, it is optimal for a single user to transmit to achieve the sum-rate capacity. This is in sharp contrast to the Gaussian MAC, in which all users must transmit, either simultaneously or at different times, in order to achieve the sum-rate capacity.

  • ISIT - On the sum-rate capacity of non-symmetric Poisson multiple Access Channel
    2016 IEEE International Symposium on Information Theory (ISIT), 2016
    Co-Authors: Ain-ul Aisha, Lifeng Lai, Yingbin Liang, Shlomo Shamai
    Abstract:

    In this paper, we characterize the sum-rate capacity of the non-symmetric Poisson multiple Access Channel (MAC). While the sum-rate capacity of the symmetric Poisson MAC has been characterized in the literature, the special property exploited in the existing method for the symmetric case does not hold for the non-symmetric Channel anymore. We obtain the optimal input that achieves the sum-rate capacity by solving a non-convex optimization problem. We show that, for certain Channel parameters, it is optimal for a single user to transmit to achieve the sum-rate capacity. This is in sharp contrast to the Gaussian MAC, in which all users must transmit, either simultaneously or at different times, in order to achieve the sum-rate capacity.

Yingbin Liang - One of the best experts on this subject based on the ideXlab platform.

  • on the sum rate capacity of non symmetric poisson multiple Access Channel
    International Symposium on Information Theory, 2016
    Co-Authors: Ain-ul Aisha, Yingbin Liang, Shlomo Shamai
    Abstract:

    In this paper, we characterize the sum-rate capacity of the non-symmetric Poisson multiple Access Channel (MAC). While the sum-rate capacity of the symmetric Poisson MAC has been characterized in the literature, the special property exploited in the existing method for the symmetric case does not hold for the non-symmetric Channel anymore. We obtain the optimal input that achieves the sum-rate capacity by solving a non-convex optimization problem. We show that, for certain Channel parameters, it is optimal for a single user to transmit to achieve the sum-rate capacity. This is in sharp contrast to the Gaussian MAC, in which all users must transmit, either simultaneously or at different times, in order to achieve the sum-rate capacity.

  • ISIT - On the sum-rate capacity of non-symmetric Poisson multiple Access Channel
    2016 IEEE International Symposium on Information Theory (ISIT), 2016
    Co-Authors: Ain-ul Aisha, Lifeng Lai, Yingbin Liang, Shlomo Shamai
    Abstract:

    In this paper, we characterize the sum-rate capacity of the non-symmetric Poisson multiple Access Channel (MAC). While the sum-rate capacity of the symmetric Poisson MAC has been characterized in the literature, the special property exploited in the existing method for the symmetric case does not hold for the non-symmetric Channel anymore. We obtain the optimal input that achieves the sum-rate capacity by solving a non-convex optimization problem. We show that, for certain Channel parameters, it is optimal for a single user to transmit to achieve the sum-rate capacity. This is in sharp contrast to the Gaussian MAC, in which all users must transmit, either simultaneously or at different times, in order to achieve the sum-rate capacity.

Remi A. Chou - One of the best experts on this subject based on the ideXlab platform.

  • ISIT - Explicit Construction of Multiple Access Channel Resolvability Codes from Source Resolvability Codes
    2020 IEEE International Symposium on Information Theory (ISIT), 2020
    Co-Authors: Rumia Sultana, Remi A. Chou
    Abstract:

    We show that the problem of code construction for multiple Access Channel resolvability can be reduced to the simpler problem of code construction for source resolvability. Specifically, we propose a multiple Access Channel resolvability coding scheme that involves randomness recycling, implemented via distributed hashing, and block-Markov encoding, where each encoding block is obtained as a combination of several source resolvability codes. Our construction is independent of the way the source resolvability codes are implemented and yields explicit coding schemes that achieve the multiple Access Channel resolvability region for an arbitrary discrete memoryless multiple Access Channel whose input alphabets are binary.

  • Allerton - Explicit Low-complexity Codes for Multiple Access Channel Resolvability
    2019 57th Annual Allerton Conference on Communication Control and Computing (Allerton), 2019
    Co-Authors: Rumia Sultana, Remi A. Chou
    Abstract:

    We design an explicit low-complexity coding scheme that achieves the multiple Access Channel resolvability region for an arbitrary discrete memoryless multiple Access Channel whose input alphabets have prime cardinalities. Unlike previous works, we do not assume Channel symmetry and rely on rate-splitting to avoid time sharing when it is known to be unnecessary. The idea of our construction is to reduce the problem of multiple Access Channel resolvability to a combination of several source resolvability problems. Our coding scheme relies on polar codes for source coding to implement source resolvability, and a block Markov coding scheme that performs randomness recycling in the different encoding blocks.

Rumia Sultana - One of the best experts on this subject based on the ideXlab platform.

  • ISIT - Explicit Construction of Multiple Access Channel Resolvability Codes from Source Resolvability Codes
    2020 IEEE International Symposium on Information Theory (ISIT), 2020
    Co-Authors: Rumia Sultana, Remi A. Chou
    Abstract:

    We show that the problem of code construction for multiple Access Channel resolvability can be reduced to the simpler problem of code construction for source resolvability. Specifically, we propose a multiple Access Channel resolvability coding scheme that involves randomness recycling, implemented via distributed hashing, and block-Markov encoding, where each encoding block is obtained as a combination of several source resolvability codes. Our construction is independent of the way the source resolvability codes are implemented and yields explicit coding schemes that achieve the multiple Access Channel resolvability region for an arbitrary discrete memoryless multiple Access Channel whose input alphabets are binary.

  • Allerton - Explicit Low-complexity Codes for Multiple Access Channel Resolvability
    2019 57th Annual Allerton Conference on Communication Control and Computing (Allerton), 2019
    Co-Authors: Rumia Sultana, Remi A. Chou
    Abstract:

    We design an explicit low-complexity coding scheme that achieves the multiple Access Channel resolvability region for an arbitrary discrete memoryless multiple Access Channel whose input alphabets have prime cardinalities. Unlike previous works, we do not assume Channel symmetry and rely on rate-splitting to avoid time sharing when it is known to be unnecessary. The idea of our construction is to reduce the problem of multiple Access Channel resolvability to a combination of several source resolvability problems. Our coding scheme relies on polar codes for source coding to implement source resolvability, and a block Markov coding scheme that performs randomness recycling in the different encoding blocks.