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Shigeaki Kuzuoka - One of the best experts on this subject based on the ideXlab platform.

  • On the smooth Rényi entropy and variable-Length source coding allowing errors
    2016 IEEE International Symposium on Information Theory (ISIT), 2016
    Co-Authors: Shigeaki Kuzuoka
    Abstract:

    In this paper, we consider the problem of variable-Length source coding allowing errors. The exponential moment of the Codeword Length is analyzed in the non-asymptotic regime and in the asymptotic regime. Our results show that the smooth Rényi entropy characterizes the optimal exponential moment of the Codeword Length.

  • ISIT - On the smooth Rényi entropy and variable-Length source coding allowing errors
    2016 IEEE International Symposium on Information Theory (ISIT), 2016
    Co-Authors: Shigeaki Kuzuoka
    Abstract:

    In this paper, we consider the problem of variable-Length source coding allowing errors. The exponential moment of the Codeword Length is analyzed in the non-asymptotic regime and in the asymptotic regime. Our results show that the smooth Renyi entropy characterizes the optimal exponential moment of the Codeword Length.

  • On the Smooth Renyi Entropy and Variable-Length Source Coding Allowing Errors
    arXiv: Information Theory, 2015
    Co-Authors: Shigeaki Kuzuoka
    Abstract:

    In this paper, we consider the problem of variable-Length source coding allowing errors. The exponential moment of the Codeword Length is analyzed in the non-asymptotic regime and in the asymptotic regime. Our results show that the smooth Renyi entropy characterizes the optimal exponential moment of the Codeword Length.

  • ISITA - Relations between universal FV and FF source codes
    2010 International Symposium On Information Theory & Its Applications, 2010
    Co-Authors: Shigeaki Kuzuoka
    Abstract:

    Universal lossless source coding for general sources are considered. Our results reveal that the definition of the universality of fixed-to-variable Length coding (FV coding) based on the redundancy criterion is not equivalent to the one based on the average Codeword Length criterion. Moreover, it is clarified that, when we adopt the redundancy criterion, the existence of a universal FV code implies the existence of a universal fixed-to-fixed Length code (FF code). On the other hand, it is also clarified that, when we adopt the average Codeword Length criterion, the existence of a universal FV code does not imply the existence of a universal FF code. Further, the relation between universal source coding and universal hypothesis testing is also investigated.

Amir K. Khandani - One of the best experts on this subject based on the ideXlab platform.

  • Scheduling and Codeword Length Optimization in Time Varying Wireless Networks
    2006 IEEE International Symposium on Information Theory, 2006
    Co-Authors: Mehdi Ansari Sadrabadi, Alireza Bayesteh, Amir K. Khandani
    Abstract:

    In this paper, a downlink scenario in which a single-antenna base station communicates with K single antenna users, over a time-correlated fading channel, is considered. It is assumed that channel state information is perfectly known at each receiver, while the statistical characteristics of the fading process and the fading gain at the beginning of each frame are known to the transmitter. By evaluating the random coding error exponent of the time-correlated fading channel, we show that there is an optimal Codeword Length which maximizes the throughput. We examine the throughput of the conventional scheduling that transmits to the user with the maximum signal to noise ratio using both fixed Length Codewords and variable Length Codewords. Although optimizing the Codeword Length improves the performance, it is shown that using the conventional scheduling, a gap of Omega(radiclog log log K) exists between the achievable throughput and the maximum possible throughput of the system. We propose a simple scheduling that considers both the signal to noise ratio and the channel time variation. We show that by using this scheduling, the gap between the achievable throughput and the maximum throughput of the system approaches zero

  • ISIT - Scheduling and Codeword Length Optimization in Time Varying Wireless Networks
    2006 IEEE International Symposium on Information Theory, 2006
    Co-Authors: Mehdi Ansari Sadrabadi, Alireza Bayesteh, Amir K. Khandani
    Abstract:

    In this paper, a downlink scenario in which a single-antenna base station communicates with K single antenna users, over a time-correlated fading channel, is considered. It is assumed that channel state information is perfectly known at each receiver, while the statistical characteristics of the fading process and the fading gain at the beginning of each frame are known to the transmitter. By evaluating the random coding error exponent of the time-correlated fading channel, we show that there is an optimal Codeword Length which maximizes the throughput. We examine the throughput of the conventional scheduling that transmits to the user with the maximum signal to noise ratio using both fixed Length Codewords and variable Length Codewords. Although optimizing the Codeword Length improves the performance, it is shown that using the conventional scheduling, a gap of Omega(radiclog log log K) exists between the achievable throughput and the maximum possible throughput of the system. We propose a simple scheduling that considers both the signal to noise ratio and the channel time variation. We show that by using this scheduling, the gap between the achievable throughput and the maximum throughput of the system approaches zero

  • scheduling and Codeword Length optimization in time varying wireless networks
    arXiv: Information Theory, 2006
    Co-Authors: Mehdi Ansari Sadrabadi, Alireza Bayesteh, Amir K. Khandani
    Abstract:

    In this paper, a downlink scenario in which a single-antenna base station communicates with K single antenna users, over a time-correlated fading channel, is considered. It is assumed that channel state information is perfectly known at each receiver, while the statistical characteristics of the fading process and the fading gain at the beginning of each frame are known to the transmitter. By evaluating the random coding error exponent of the time-correlated fading channel, it is shown that there is an optimal Codeword Length which maximizes the throughput. The throughput of the conventional scheduling that transmits to the user with the maximum signal to noise ratio is examined using both fixed Length Codewords and variable Length Codewords. Although optimizing the Codeword Length improves the performance, it is shown that using the conventional scheduling, the gap between the achievable throughput and the maximum possible throughput of the system tends to infinity as K goes to infinity. A simple scheduling that considers both the signal to noise ratio and the channel time variation is proposed. It is shown that by using this scheduling, the gap between the achievable throughput and the maximum throughput of the system approaches zero.

  • Scheduling and Codeword Length Optimization in Time Varying Wireless Networks
    2006 40th Annual Conference on Information Sciences and Systems, 2006
    Co-Authors: Mehdi Ansari Sadrabadi, Alireza Bayesteh, Amir K. Khandani
    Abstract:

    In this paper, a downlink scenario in which a single-antenna base station communicates with K single antenna users, over a time-correlated fading channel, is considered. It is assumed that channel state information is perfectly known at each receiver, while the statistical characteristics of the fading process and the fading gain at the beginning of each frame are known to the transmitter. By evaluating the random coding error exponent of the time-correlated fading channel, we show that there is an optimal Codeword Length which maximizes the throughput. We examine the throughput of conventional scheduling that transmits to the user with the maximum signal to noise ratio using both fixed Length Codewords and variable Length Codewords. Although optimizing the Codeword Length improves the performance, it is shown that using the conventional scheduling, a gap of Omega(radiclog log log K) exists between the achievable throughput and the maximum possible throughput of the system. We propose a simple scheduling that considers both the signal to noise ratio and the channel time variation. In this case, among users which their fading gain is above a threshold, user that has minimum channel time variation is selected. We show that by using this scheduling, the gap between the achievable throughput and maximum throughput of the system approaches o(1).

Mehdi Ansari Sadrabadi - One of the best experts on this subject based on the ideXlab platform.

  • Scheduling and Codeword Length Optimization in Time Varying Wireless Networks
    2006 IEEE International Symposium on Information Theory, 2006
    Co-Authors: Mehdi Ansari Sadrabadi, Alireza Bayesteh, Amir K. Khandani
    Abstract:

    In this paper, a downlink scenario in which a single-antenna base station communicates with K single antenna users, over a time-correlated fading channel, is considered. It is assumed that channel state information is perfectly known at each receiver, while the statistical characteristics of the fading process and the fading gain at the beginning of each frame are known to the transmitter. By evaluating the random coding error exponent of the time-correlated fading channel, we show that there is an optimal Codeword Length which maximizes the throughput. We examine the throughput of the conventional scheduling that transmits to the user with the maximum signal to noise ratio using both fixed Length Codewords and variable Length Codewords. Although optimizing the Codeword Length improves the performance, it is shown that using the conventional scheduling, a gap of Omega(radiclog log log K) exists between the achievable throughput and the maximum possible throughput of the system. We propose a simple scheduling that considers both the signal to noise ratio and the channel time variation. We show that by using this scheduling, the gap between the achievable throughput and the maximum throughput of the system approaches zero

  • ISIT - Scheduling and Codeword Length Optimization in Time Varying Wireless Networks
    2006 IEEE International Symposium on Information Theory, 2006
    Co-Authors: Mehdi Ansari Sadrabadi, Alireza Bayesteh, Amir K. Khandani
    Abstract:

    In this paper, a downlink scenario in which a single-antenna base station communicates with K single antenna users, over a time-correlated fading channel, is considered. It is assumed that channel state information is perfectly known at each receiver, while the statistical characteristics of the fading process and the fading gain at the beginning of each frame are known to the transmitter. By evaluating the random coding error exponent of the time-correlated fading channel, we show that there is an optimal Codeword Length which maximizes the throughput. We examine the throughput of the conventional scheduling that transmits to the user with the maximum signal to noise ratio using both fixed Length Codewords and variable Length Codewords. Although optimizing the Codeword Length improves the performance, it is shown that using the conventional scheduling, a gap of Omega(radiclog log log K) exists between the achievable throughput and the maximum possible throughput of the system. We propose a simple scheduling that considers both the signal to noise ratio and the channel time variation. We show that by using this scheduling, the gap between the achievable throughput and the maximum throughput of the system approaches zero

  • scheduling and Codeword Length optimization in time varying wireless networks
    arXiv: Information Theory, 2006
    Co-Authors: Mehdi Ansari Sadrabadi, Alireza Bayesteh, Amir K. Khandani
    Abstract:

    In this paper, a downlink scenario in which a single-antenna base station communicates with K single antenna users, over a time-correlated fading channel, is considered. It is assumed that channel state information is perfectly known at each receiver, while the statistical characteristics of the fading process and the fading gain at the beginning of each frame are known to the transmitter. By evaluating the random coding error exponent of the time-correlated fading channel, it is shown that there is an optimal Codeword Length which maximizes the throughput. The throughput of the conventional scheduling that transmits to the user with the maximum signal to noise ratio is examined using both fixed Length Codewords and variable Length Codewords. Although optimizing the Codeword Length improves the performance, it is shown that using the conventional scheduling, the gap between the achievable throughput and the maximum possible throughput of the system tends to infinity as K goes to infinity. A simple scheduling that considers both the signal to noise ratio and the channel time variation is proposed. It is shown that by using this scheduling, the gap between the achievable throughput and the maximum throughput of the system approaches zero.

  • Scheduling and Codeword Length Optimization in Time Varying Wireless Networks
    2006 40th Annual Conference on Information Sciences and Systems, 2006
    Co-Authors: Mehdi Ansari Sadrabadi, Alireza Bayesteh, Amir K. Khandani
    Abstract:

    In this paper, a downlink scenario in which a single-antenna base station communicates with K single antenna users, over a time-correlated fading channel, is considered. It is assumed that channel state information is perfectly known at each receiver, while the statistical characteristics of the fading process and the fading gain at the beginning of each frame are known to the transmitter. By evaluating the random coding error exponent of the time-correlated fading channel, we show that there is an optimal Codeword Length which maximizes the throughput. We examine the throughput of conventional scheduling that transmits to the user with the maximum signal to noise ratio using both fixed Length Codewords and variable Length Codewords. Although optimizing the Codeword Length improves the performance, it is shown that using the conventional scheduling, a gap of Omega(radiclog log log K) exists between the achievable throughput and the maximum possible throughput of the system. We propose a simple scheduling that considers both the signal to noise ratio and the channel time variation. In this case, among users which their fading gain is above a threshold, user that has minimum channel time variation is selected. We show that by using this scheduling, the gap between the achievable throughput and maximum throughput of the system approaches o(1).

Alireza Bayesteh - One of the best experts on this subject based on the ideXlab platform.

  • Scheduling and Codeword Length Optimization in Time Varying Wireless Networks
    2006 IEEE International Symposium on Information Theory, 2006
    Co-Authors: Mehdi Ansari Sadrabadi, Alireza Bayesteh, Amir K. Khandani
    Abstract:

    In this paper, a downlink scenario in which a single-antenna base station communicates with K single antenna users, over a time-correlated fading channel, is considered. It is assumed that channel state information is perfectly known at each receiver, while the statistical characteristics of the fading process and the fading gain at the beginning of each frame are known to the transmitter. By evaluating the random coding error exponent of the time-correlated fading channel, we show that there is an optimal Codeword Length which maximizes the throughput. We examine the throughput of the conventional scheduling that transmits to the user with the maximum signal to noise ratio using both fixed Length Codewords and variable Length Codewords. Although optimizing the Codeword Length improves the performance, it is shown that using the conventional scheduling, a gap of Omega(radiclog log log K) exists between the achievable throughput and the maximum possible throughput of the system. We propose a simple scheduling that considers both the signal to noise ratio and the channel time variation. We show that by using this scheduling, the gap between the achievable throughput and the maximum throughput of the system approaches zero

  • ISIT - Scheduling and Codeword Length Optimization in Time Varying Wireless Networks
    2006 IEEE International Symposium on Information Theory, 2006
    Co-Authors: Mehdi Ansari Sadrabadi, Alireza Bayesteh, Amir K. Khandani
    Abstract:

    In this paper, a downlink scenario in which a single-antenna base station communicates with K single antenna users, over a time-correlated fading channel, is considered. It is assumed that channel state information is perfectly known at each receiver, while the statistical characteristics of the fading process and the fading gain at the beginning of each frame are known to the transmitter. By evaluating the random coding error exponent of the time-correlated fading channel, we show that there is an optimal Codeword Length which maximizes the throughput. We examine the throughput of the conventional scheduling that transmits to the user with the maximum signal to noise ratio using both fixed Length Codewords and variable Length Codewords. Although optimizing the Codeword Length improves the performance, it is shown that using the conventional scheduling, a gap of Omega(radiclog log log K) exists between the achievable throughput and the maximum possible throughput of the system. We propose a simple scheduling that considers both the signal to noise ratio and the channel time variation. We show that by using this scheduling, the gap between the achievable throughput and the maximum throughput of the system approaches zero

  • scheduling and Codeword Length optimization in time varying wireless networks
    arXiv: Information Theory, 2006
    Co-Authors: Mehdi Ansari Sadrabadi, Alireza Bayesteh, Amir K. Khandani
    Abstract:

    In this paper, a downlink scenario in which a single-antenna base station communicates with K single antenna users, over a time-correlated fading channel, is considered. It is assumed that channel state information is perfectly known at each receiver, while the statistical characteristics of the fading process and the fading gain at the beginning of each frame are known to the transmitter. By evaluating the random coding error exponent of the time-correlated fading channel, it is shown that there is an optimal Codeword Length which maximizes the throughput. The throughput of the conventional scheduling that transmits to the user with the maximum signal to noise ratio is examined using both fixed Length Codewords and variable Length Codewords. Although optimizing the Codeword Length improves the performance, it is shown that using the conventional scheduling, the gap between the achievable throughput and the maximum possible throughput of the system tends to infinity as K goes to infinity. A simple scheduling that considers both the signal to noise ratio and the channel time variation is proposed. It is shown that by using this scheduling, the gap between the achievable throughput and the maximum throughput of the system approaches zero.

  • Scheduling and Codeword Length Optimization in Time Varying Wireless Networks
    2006 40th Annual Conference on Information Sciences and Systems, 2006
    Co-Authors: Mehdi Ansari Sadrabadi, Alireza Bayesteh, Amir K. Khandani
    Abstract:

    In this paper, a downlink scenario in which a single-antenna base station communicates with K single antenna users, over a time-correlated fading channel, is considered. It is assumed that channel state information is perfectly known at each receiver, while the statistical characteristics of the fading process and the fading gain at the beginning of each frame are known to the transmitter. By evaluating the random coding error exponent of the time-correlated fading channel, we show that there is an optimal Codeword Length which maximizes the throughput. We examine the throughput of conventional scheduling that transmits to the user with the maximum signal to noise ratio using both fixed Length Codewords and variable Length Codewords. Although optimizing the Codeword Length improves the performance, it is shown that using the conventional scheduling, a gap of Omega(radiclog log log K) exists between the achievable throughput and the maximum possible throughput of the system. We propose a simple scheduling that considers both the signal to noise ratio and the channel time variation. In this case, among users which their fading gain is above a threshold, user that has minimum channel time variation is selected. We show that by using this scheduling, the gap between the achievable throughput and maximum throughput of the system approaches o(1).

Ting-yi Wu - One of the best experts on this subject based on the ideXlab platform.

  • An A*-Based Algorithm for Constructing Reversible Variable Length Codes with Minimum Average Codeword Length
    IEEE Transactions on Communications, 2010
    Co-Authors: Yuh-ming Huang, Ting-yi Wu
    Abstract:

    Variable Length codes (VLCs) are widely adopted in many compression standards due to their good coding efficiency on average Codeword Length. However, an inherent problem with a VLC is that an error of even one bit can cause serious error propagation and thus loss of synchronization at the receiver, which would lead to a series of non-correctly decoded symbols. Reversible variable Length codes (RVLCs) were introduced to significantly mitigate this phenomenon. In this work, a method to find an optimal RVLC in terms of the minimum average Codeword Length is first formulated as a tree-searching problem, and then, instead of performing an exhaustive search, an A*-based construction algorithm is proposed to find an optimal RVLC. The proposed algorithm has been applied to several benchmarks for sources and has found respective optimal symmetric and asymmetric RVLCs.