We consider Slepian-Wolf code design based on low-density parity-check (LDPC) coset codes. The density evolution formula for Slepian-Wolf coding is derived. An intimate connection between Slepian-Wolf coding and chann...
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We consider Slepian-Wolf code design based on low-density parity-check (LDPC) coset codes. The density evolution formula for Slepian-Wolf coding is derived. An intimate connection between Slepian-Wolf coding and channel coding is then established. Specifically we show that, under density evolution, each Slepian-Wolf coding problem is equivalent to a channel coding problem for a binary-input output-symmetric channel.
For wireless video, the present paper demonstrates that combining adaptive source and channel coding can provide a robust service over a wide range of transmission channel conditions. Various feedback-controlled adapt...
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For wireless video, the present paper demonstrates that combining adaptive source and channel coding can provide a robust service over a wide range of transmission channel conditions. Various feedback-controlled adaptive coding solutions are considered for orthogonal frequency-division multiplexing-based systems. At the receiver, the reliabilities of subchannels (SCHs) are estimated and decisions are fed back to the transmitter to adapt modulation modes and channel code-rates to provide reliable transmission and yet avoid over-protection. The resulting available transmission capacity (which can vary widely with channel conditions) can inform an online collaborating source coder which itself exploits the available feedback to reduce error propagation. To ensure further improvement for fading channels, an efficient low-delay retransmission arrangement is also considered in which only the contents of unreliable SCHs within an erroneous packet are retransmitted. Simulation results demonstrate that such collaborative adaptive source and channel coding can provide efficient use of a continuously varying wireless channel.
We consider block codes whose rate converges to the channel capacity with increasing blocklength at a certain speed and examine the best possible decay of the probability of error. For discrete memoryless channels, we...
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We consider block codes whose rate converges to the channel capacity with increasing blocklength at a certain speed and examine the best possible decay of the probability of error. For discrete memoryless channels, we prove that a moderate deviation principle holds for all convergence rates between the large deviation and the central limit theorem regimes.
For a fixed total bandwidth expansion factor, we consider the problem of optimal bandwidth allocation among the source coder, the channel coder, and the spread-spectrum unit for a direct-sequence code-division multipl...
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For a fixed total bandwidth expansion factor, we consider the problem of optimal bandwidth allocation among the source coder, the channel coder, and the spread-spectrum unit for a direct-sequence code-division multiple-access system operating over a frequency-selective fading channel with narrow-band interference. Assuming a Gaussian source with the optimum scalar quantizer, and a binary convolutional code with soft-decision decoding, and further assuming that the self-interference is negligible, we obtain both a lower and an upper bound on the end-to-end average source distortion. The joint three-way constrained optimization of the source code rate, the channel code rate, and the spreading factor can be simplified into an unconstrained optimization problem over two variables. Upon fixing the channel code rate, we show that both upper and lower bound-based distortion functions are convex functions of the source code rate. Because an explicit solution for the optimum source code rate, i.e., one that minimizes the average distortion, is difficult to obtain, computer-based search techniques are employed. Numerical results are presented for the optimum source code rate and spreading factor, parameterized by the channel code rate and code constraint length. The optimal bandwidth allocation, in general, depends on the system and the channel conditions, such as the total number of active users, the average jammer-to-signal power ratio, and the number of resolved multipath components together with their power delay profile.
This study provides a general diversity analysis for joint complex diversity coding (CDC) and channel coding-based space-time-frequency codeing is provided. The mapping designs from channel coding to CDC are crucial f...
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This study provides a general diversity analysis for joint complex diversity coding (CDC) and channel coding-based space-time-frequency codeing is provided. The mapping designs from channel coding to CDC are crucial for efficient exploitation of the diversity potential. This study provides and proves a sufficient condition of full diversity construction with joint three-dimensional CDC and channel coding, bit-interleaved coded complex diversity coding and symbol-interleaved coded complex diversity coding. Both non-iterative and iterative detections of joint channel code and CDC transmission are investigated. The proposed minimum mean-square error-based iterative soft decoding achieves the performance of the soft sphere decoding with reduced complexity.
We consider the time-division multiple-access relay channel (MARC) with block-fading channels and Gaussian noise, where two sources communicate with one destination with the help of one relay. Such a system can be use...
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We consider the time-division multiple-access relay channel (MARC) with block-fading channels and Gaussian noise, where two sources communicate with one destination with the help of one relay. Such a system can be used for the cooperative uplink of two mobile stations to a base station with the help of a relay. We propose a joint network-channel code design based on turbo codes for the MARC. We compare the proposed system with a distributed turbo code for the time-division relay channel and with a system which uses separate network-channel coding for the MARC. Our results show that the proposed code can gain diversity compared to the system for the time-division relay channel and allows to more efficiently exploit the redundancy in the transmission of the relay than separate network-channel coding. Copyright (C) 2009 John Wiley & Sons, Ltd.
In this paper, second-order coding rate of channel coding is discussed for general sequence of channels. The optimum second-order transmission rate with a constant error constraint is obtained by using the information...
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In this paper, second-order coding rate of channel coding is discussed for general sequence of channels. The optimum second-order transmission rate with a constant error constraint is obtained by using the information spectrum method. We apply this result to the discrete memoryless case, the discrete memoryless case with a cost constraint, the additive Markovian case, and the Gaussian channel case with an energy constraint. We also clarify that the Gallager bound does not give the optimum evaluation in the second-order coding rate.
In this paper, we have proposed and investigated an attractive joint source coding, channel coding, and modulation (JSCM) scheme for a two-way relaying system. We commence by quantifying the achievable capacity of the...
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In this paper, we have proposed and investigated an attractive joint source coding, channel coding, and modulation (JSCM) scheme for a two-way relaying system. We commence by quantifying the achievable capacity of the corresponding two-way relay channel before proposing low-complexity source coding schemes for concatenation with bandwidth-and power-efficient coded modulation schemes. Extrinsic information transfer (EXIT) charts are used to investigate the decoding convergence of the joint source and channel decoder and for the overall system design. The quality of the decoded source signals is quantified using the bit error ratio (BER) metric. It is found that the two-way-relay-based JSCM scheme is capable of attaining a combined coding and relaying gain of 5.7 dB over the conventional noncooperative JSCM scheme when communicating over uncorrelated Rayleigh fading channels in an outdoor environment.
Industrial wireless sensor networks (IWSN) begin to occupy wide areas in the industry for applications such as factory automation. To meet the strict latency and reliability requirements for (IWSN), channel coding is ...
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ISBN:
(纸本)9781728101170
Industrial wireless sensor networks (IWSN) begin to occupy wide areas in the industry for applications such as factory automation. To meet the strict latency and reliability requirements for (IWSN), channel coding is proposed to be used in the physical layer. To this aim, a comparison study is carried out in this paper among three different modern coding techniques, i.e. turbo, LDPC, and convolutional coding. The goal of this study is to define which coding technique better meets IWSN requirements. LDPC is shown to provide a good performance by means of latency and reliability. In addition, low latency HARQ based on error rate estimation is proposed in this paper. The proposed scheme utilizes few LDPC decoder iterations and can provide up to 5 dB gain compared to another scheme where the decoding process is completely skipped.
In this paper we study channels where a side-information sequence is available strictly causally at the transmitter, i.e., the channel input at time k may depend on the side-information sequence up to and including ti...
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ISBN:
(纸本)9781424413973
In this paper we study channels where a side-information sequence is available strictly causally at the transmitter, i.e., the channel input at time k may depend on the side-information sequence up to and including time k - 1. This is in contrast to Shannon's channel coding with causal side-information at the transmitter where the channel input at time k may depend on the side-information sequence up to and including time k. We consider side-information sequences with memory and study the Gaussian and modulo-additive channels.
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