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Mark M. Wilde - One of the best experts on this subject based on the ideXlab platform.

  • Minimal-Memory, Noncatastrophic, Polynomial-Depth Quantum Convolutional Encoders
    IEEE Transactions on Information Theory, 2013
    Co-Authors: Monireh Houshmand, Saied Hosseini-khayat, Mark M. Wilde
    Abstract:

    Quantum Convolutional Coding is a technique for enCoding a stream of quantum information before transmitting it over a noisy quantum channel. Two important goals in the design of quantum Convolutional encoders are to minimize the memory required by them and to avoid the catastrophic propagation of errors. In a previous paper, we determined minimal-memory, noncatastrophic, polynomial-depth encoders for a few exemplary quantum Convolutional codes. In this paper, we elucidate a general technique for finding an encoder of an arbitrary quantum Convolutional code such that the encoder possesses these desirable properties. We also provide an elementary proof that these encoders are nonrecursive. Finally, we apply our technique to many quantum Convolutional codes from the literature.

  • minimal memory non catastrophic polynomial depth quantum Convolutional encoders
    arXiv: Quantum Physics, 2011
    Co-Authors: Monireh Houshmand, Saied Hosseinikhayat, Mark M. Wilde
    Abstract:

    Quantum Convolutional Coding is a technique for enCoding a stream of quantum information before transmitting it over a noisy quantum channel. Two important goals in the design of quantum Convolutional encoders are to minimize the memory required by them and to avoid the catastrophic propagation of errors. In a previous paper, we determined minimal-memory, non-catastrophic, polynomial-depth encoders for a few exemplary quantum Convolutional codes. In this paper, we elucidate a general technique for finding an encoder of an arbitrary quantum Convolutional code such that the encoder possesses these desirable properties. We also provide an elementary proof that these encoders are non-recursive. Finally, we apply our technique to many quantum Convolutional codes from the literature.

  • Quantum Convolutional Coding with shared entanglement: general structure
    Quantum Information Processing, 2010
    Co-Authors: Mark M. Wilde, Todd A. Brun
    Abstract:

    We present a general theory of entanglement-assisted quantum Convolutional Coding. The codes have a Convolutional or memory structure, they assume that the sender and receiver share noiseless entanglement prior to quantum communication, and they are not restricted to possess the Calderbank–Shor–Steane structure as in previous work. We provide two significant advances for quantum Convolutional Coding theory. We first show how to “expand” a given set of quantum Convolutional generators. This expansion step acts as a preprocessor for a polynomial symplectic Gram–Schmidt orthogonalization procedure that simplifies the commutation relations of the expanded generators to be the same as those of entangled Bell states (ebits) and ancilla qubits. The above two steps produce a set of generators with equivalent error-correcting properties to those of the original generators. We then demonstrate how to perform online enCoding and deCoding for a stream of information qubits, halves of ebits, and ancilla qubits. The upshot of our theory is that the quantum code designer can engineer quantum Convolutional codes with desirable error-correcting properties without having to worry about the commutation relations of these generators.

Lajos Hanzo - One of the best experts on this subject based on the ideXlab platform.

  • H.264 Wireless Video Telephony Using Iteratively-Detected Binary Self-Concatenated Coding
    2016
    Co-Authors: Muhammad Fasih, Uddin Butt, Lajos Hanzo
    Abstract:

    Abstract — In this contribution we propose a robust H.264 coded wireless video transmission scheme using iteratively de-coded self-concatenated Convolutional Coding (SECCC). The proposed SECCC scheme is composed of constituent recursive systematic Convolutional (RSC) codes and an interleaver is used to randomise the extrinsic information exchanged between the constituent RSC codes. Additionally, a puncturer is used to increase the achievable bandwidth efficiency. At the receiver self-iterative deCoding is invoked between the hypothetical decoder components. The performance of the system was evaluated using the H.264/AVC source codec for interactive video telephony. Furthermore, EXIT charts were utilised in order to analyse the convergence behaviour of the SECCC scheme advocated. We demonstrate the efficiency of this approach by showing that the video quality is significantly improved, when using the binar

  • h 264 wireless video telephony using iteratively detected binary self concatenated Coding
    Vehicular Technology Conference, 2010
    Co-Authors: Muhammad Fasih Uddin Butt, Lajos Hanzo
    Abstract:

    In this contribution we propose a robust H.264 coded wireless video transmission scheme using iteratively decoded self-concatenated Convolutional Coding (SECCC). The proposed SECCC scheme is composed of constituent recursive systematic Convolutional (RSC) codes and an interleaver is used to randomise the extrinsic information exchanged between the constituent RSC codes. Additionally, a puncturer is used to increase the achievable bandwidth efficiency. At the receiver self-iterative deCoding is invoked between the hypothetical decoder components. The performance of the system was evaluated using the H.264/AVC source codec for interactive video telephony. Furthermore, EXIT charts were utilised in order to analyse the convergence behaviour of the SECCC scheme advocated. We demonstrate the efficiency of this approach by showing that the video quality is significantly improved, when using the binary SECCC scheme. More explicitly, the proposed system exhibits an $E_b/N_0$ gain of $6~dB$ at the PSNR degradation point of $2~dB$ in comparison to the identical-rate benchmarker carrying out RSC Coding and puncturing, while communicating over correlated Rayleigh fading channels.

  • turbo Coding turbo equalisation and space time Coding for transmission over fading channels
    2002
    Co-Authors: Lajos Hanzo
    Abstract:

    Acknowledgments.Historical Perspective, Motivation and Outline. I Convolutional and Block Coding. Convolutional Channel Coding. Block Coding. Soft DeCoding and Performance of BCH Codes. II Turbo Convolutional and Turbo Block Coding. Turbo Convolutional Coding. The Super Trellis Structure of Convolutional Turbo Codes. Turbo BCH Coding. Redundant Residue Number System Codes. III Coded Modulation: TCM, TTCM, BICM, BICM ID. Coded Modulation Theory and Performance. IV Space Time Block and Space Time Trellis Coding. Space time Block Codes. Space Time Trellis Codes. Turbo coded Adaptive QAM versus Space time Trellis Coding. V Turbo Equalisation. Turbo coded Partial response Modulation. Turbo Equalisation for Partial response Systems. Turbo Equalisation Performance Bound. Comparative Study of Turbo Equalisers. Reduced complexity Turbo Equaliser. Turbo Equalisation for Space time Trellis coded Systems. Summary and Conclusions. Bibliography. Subject Index. Author Index. About the Authors.Other Related Wiley and IEEE Press Books.

  • ofdm based turbo coded hierarchical and non hierarchical terrestrial mobile digital video broadcasting
    IEEE Transactions on Broadcasting, 2000
    Co-Authors: Thomas Keller, Lajos Hanzo
    Abstract:

    The feasibility of terrestrial digital video broadcast (DVB) to mobile receivers is studied and turbo coded performance enhancements are proposed. Initially, the MPEG-2 codec is subjected to a rigorous bit error sensitivity investigation, in order to assist in designing various error protection schemes for wireless DVB transmission. The turbo codec is shown to provide signal-to-noise ratio (SNR) performance advantages in excess of 5-6 dB over conventional Convolutional Coding both in terms of bit error rate and video quality. Our experiments suggested that-despite our expectations-multi-class data partitioning did not result in error resilience improvements, since a high proportion of relatively sensitive video bits had to be relegated to the lower integrity subchannel, when invoking a powerful low-rate channel codec in the high-integrity protection class. Nonetheless, DVB transmission to mobile receivers is feasible, when using turbo-coded OFDM transceivers at realistic power-budget requirements under the investigated highly dispersive fading channel conditions. It is interesting to note furthermore that the 5-6 dB SNR improvement due to turbo Coding allows us to invoke for example the double-throughput 16-level quadrature amplitude modulation (16-QAM) mode instead of the standard Convolutional-coded 4-QAM mode. This facilitates doubling the bit rate and hence improving the video quality.

Todd A. Brun - One of the best experts on this subject based on the ideXlab platform.

  • Quantum Convolutional Coding with shared entanglement: general structure
    Quantum Information Processing, 2010
    Co-Authors: Mark M. Wilde, Todd A. Brun
    Abstract:

    We present a general theory of entanglement-assisted quantum Convolutional Coding. The codes have a Convolutional or memory structure, they assume that the sender and receiver share noiseless entanglement prior to quantum communication, and they are not restricted to possess the Calderbank–Shor–Steane structure as in previous work. We provide two significant advances for quantum Convolutional Coding theory. We first show how to “expand” a given set of quantum Convolutional generators. This expansion step acts as a preprocessor for a polynomial symplectic Gram–Schmidt orthogonalization procedure that simplifies the commutation relations of the expanded generators to be the same as those of entangled Bell states (ebits) and ancilla qubits. The above two steps produce a set of generators with equivalent error-correcting properties to those of the original generators. We then demonstrate how to perform online enCoding and deCoding for a stream of information qubits, halves of ebits, and ancilla qubits. The upshot of our theory is that the quantum code designer can engineer quantum Convolutional codes with desirable error-correcting properties without having to worry about the commutation relations of these generators.

Jiantao Zhou - One of the best experts on this subject based on the ideXlab platform.

  • On the Security of Chaotic Convolutional Coder
    IEEE Transactions on Circuits and Systems I: Regular Papers, 2011
    Co-Authors: Jiantao Zhou
    Abstract:

    This paper evaluates the security of the generalized chaotic Convolutional coder, which is a recently proposed joint error-correction and encryption scheme integrating the chaotic encryption into the Convolutional Coding. Our results show that the probability of fully recovering the pseudorandom sequence (PRS) controlling the chaotic switches is at least 0.289 under known-plaintext attack, if the number of available plaintext/ciphertext pairs p is equal to the constraint length k of the chaotic Convolutional coder. In the case that p=k+e , where e ∈ Z+, we prove that the probability to fully deduce the PRS is lower bounded by 1-2-e. Furthermore, we propose four types of chosen-plaintext attack with different deCoding complexities and efficiencies to fully derive the PRS.

  • cryptanalysis of chaotic Convolutional coder
    International Symposium on Circuits and Systems, 2010
    Co-Authors: Jiantao Zhou
    Abstract:

    In this paper, we evaluate the security of a recently proposed joint error correction and encryption approach called chaotic Convolutional coder, which integrates the chaotic encryption into the Convolutional Coding. We show that the probability of recovering the key vector controlling the chaotic switch is at least 0.289 under known-plaintext attack, if the number of available plaintext/ciphertext pairs p is equal to the constraint length k of the chaotic Convolutional coder. In the case that p = k + e, where e > 0, we prove that the probability to recover the key vector is lower bounded by 1–2−e. We also consider the security of the chaotic con-volutional coder under chosen-plaintext attack. We propose two approaches to efficiently derive the key vector without leaving tractable pattern to the register. In particular, one of these two methods based on an efficient erasure code is capable of recovering the key vector with complexity of order O(k log k).

S Kallel - One of the best experts on this subject based on the ideXlab platform.

  • efficient hybrid arq protocols with adaptive forward error correction
    IEEE Transactions on Communications, 1994
    Co-Authors: S Kallel
    Abstract:

    In this paper, efficient stop-and-wait, go-back-N and selective-repeat hybrid ARQ protocols with adaptive forward error correction (AFEC) using Convolutional Coding are proposed and analyzed. The basic idea is to vary the Coding rate for error correction according to system parameters, such as the signal-to-noise ratio, the round trip delay and the buffer size at the receiver, so as to maximize the throughput efficiency. The performances of the proposed ARQ protocols are evaluated for two channel models: a non-fading and an ideally-interleaved Rayleigh-fading additive white Gaussian noise channel. In all cases it is found that the hybrid ARQ protocols with AFEC yield a comparatively high throughput under all channel conditions. >

  • practical implementation of a mobile data link protocol with a type ii hybrid arq scheme and code combining
    Vehicular Technology Conference, 1993
    Co-Authors: S Bakhtiyari, T Chen, S Kallel, Victor C M Leung
    Abstract:

    The design of an efficient mobile data link protocol (MDLP) based on a Type II hybrid automatic request for repetition (ARQ) scheme using Convolutional Coding and code combining is presented. An adaptive Coding scheme for the header is proposed and analyzed. Simulation results show significant improvement in throughput at low SNR as compared to conventional schemes. Precise specification of the MDLP using a formal description technique based on Estelle is outlined and discussed.