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Performance evaluation of super-orthogonal space-time trellis codes using a moment generating function-based approach

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IEEE TRANSACTIONS ON SIGNAL PROCESSING 2003年第11期51卷 2739-2751页

作者： Simon, MK Jafarkhani, H Univ Calif Los Angeles Dept Elect Engn Los Angeles CA 90095 USA Univ Calif Irvine Dept Elect & Comp Engn Irvine CA 92697 USA

Recently, a new class of space-time codes called super-orthogonal trellis codes was introduced that combine set-partitioning with a super set of orthogonal space-time block codes in such a way as to provide full diversity with increased rate and improved coding gain over previous space-time trellis code (STTC) constructions. Here, we extend the moment generating function-based method, which was previously applied to analyzing the performance of space-time block orthogonal and trellis codes, to the above-mentioned super-orthogonal codes. It is shown that the maximum-likelihood metric and expressions for the pairwise error probability previously developed for the Alamouti space-time block code combined with multidimensional trellis-coded modulation can be readily extended to the super-orthogonal case. As such, the evaluation of the pairwise error probability for the latter can be performed in a similar manner to that previously described with the specific results. depending on the particular trellis code design.

关键词： error probablity performance space time coding trellis coding

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Performance analysis of modified/quadrature partial response-trellis coded modulation (M/QPR-TCM) systems

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IEICE TRANSACTIONS ON COMMUNICATIONS 1996年第10期E79B卷 1570-1576页

作者： Ucan, ON Faculty of Electrical and Electronics Istanbul Technical University 80626 Maslak Istanbul Turkey

In this paper, partial response signalling and trellis coded modulation are considered together to improve bandwidth efficiency and error performance for M-QAM and denoted as Modified/Quadrature Partial Response-trellis Coded Modulation (M/QPR-TCM) and two new non-catastrophic schemes M/6QPR-TCM and M/9QPR-TCM are introduced for 4QAM, In colored noise with correlation coefficient less than zero, the proposed schemes perform better than in AWGN case. Another interesting result is that when the combined system is used on a Rician fading channel, the bit error probability upper bounds of the proposed systems are better than their counterparts the 4QAM-TCM systems with 2 and 4 states, respectively for SNR values greater than a threshold, which have the best error performance in the literature.

关键词： trellis coding partial response signalling M/QPR-TCM M/6QPR-TCM M/9QPR-TCM colored noise fading channel

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Dirty paper coding schemes for MIMO broadcast channels

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ANNALS OF TELECOMMUNICATIONS 2007年第9-10期62卷 1143-1170页

作者： Lasaulce, Samson Dumont, Julien Mohammad-Khani, Gholam Reza Visoz, Raphael Supelec CNRS Signaux & Syst Lab F-91192 Gif Sur Yvette France Univ Marne la Vallee IGM LabInfo Lab Syst Commun F-77454 Marne La Vallee 2 France France Telecom Div R&D F-92794 Issy Les Moulineaux 9 France

We propose several dirty paper coding schemes for the broadcast channel when both the transmitter and receivers are equipped with multiple antennas. These schemes are based on channel state information at the transmitter and inspired from information-theoretic concepts. The proposed end-to-end algorithms allows us to evaluate the performance of the broadcast channel in terms of bit error rates and not in terms of coding rates as it is usually the case in the literature. Different inner coding schemes such as the ZF-DPC and MMSE-DPC and different outer coding schemes such as the THS, SCS and TCQ are compared and discussed. We als o consider the DPC idea as a way of implementing a multiple access scheme. In this respect it is compared with the well-known TDMA scheme. Sometimes our conclusions show quite surprising results in comparison to what is expected by pure information-theoretic considerations.

关键词： coding information theory mobile radiocommunication trellis coding error rate channel capacity signal interference

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PERFORMANCE EVALUATION METHOD OF trellis-CODED MODULATION SCHEME WITHOUT UNIFORMITY

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IEICE TRANSACTIONS ON FUNDAMENTALS OF ELECTRONICS COMMUNICATIONS AND COMPUTER SCIENCES 1994年第8期E77A卷 1267-1273页

作者： OGIWARA, H OOHIRA, K Nagaoka Univ of Technology Nagaokashi Japan

An encoder of a trellis coded modulation (TCM) is composed of a linear convolutional encoder followed by a mapper to channel signals. A new condition, under which the performance evaluation of the TCM is possible based on the 2nu state error state transition diagram, is proposed, where nu is the number of delay elements in the convolutional encoder. There have been proposed three similar methods. This paper points out the restriction of the previous methods, and proposes a new method. The condition, under which the previous method is useful, is called uniformity, such as, the error weight profile is independent from the encoder state. When uniformity does not hold, we discuss to divide an error state into substates based on the coset decomposition of output vectors of the convolutional encoder. The coset is determined by the vector called coset selector. If the condition defined as equal dividing holds, the subdivided states can be merged and the performance can be evaluated based on the 2nu state transition diagram, even for the codes without uniformity. When the row rank of the transformation matrix, from the input vector of the encoder to the coset selector vector, is full, the equal dividing condition holds under the assumption of equally probable i.i.d. (independently identically distributed) input sequence. For TCM schemes without uniformity (in the case, previous methods can not be applied), upper bounds of the bit error rate are evaluated by the proposed method and compared with the simulation results. The difference is less than 10% in the range of bit error rate < 10(-4).

关键词： trellis coding CODED MODULATION UNIFORMITY UPPER BOUND ERROR WEIGHT PROFILE

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ENTROPY-CONSTRAINED trellis-CODED QUANTIZATION

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IEEE TRANSACTIONS ON INFORMATION THEORY 1992年第2期38卷 415-426页

作者： FISCHER, TR MIN, W UNIV WISCONSIN DEPT ELECT ENGN PLATTEVILLE WI 53818 USA

trellis-coded quantization is generalized to allow noiseless coding of the trellis branch reproduction symbols. An entropy-constrained trellis-coded quantization (ECTCQ) design algorithm is presented, based on the generalized Lloyd algorithm for trellis code design and the entropy-constrained vector quantization design algorithm. ECTCQ systems are designed for memoryless Gaussian and Laplacian sources, and for first- and second-order Gauss-Markov sources. With an 8-state trellis, the mean-squared error ECTCQ encoding performance for memoryless sources with smooth densities is within about 0.5 dB of the rate-distortion function. Small additional improvements are achieved with larger trellises. Similar, though not quite as good, performance is achieved for the Gauss-Markov sources by using the ECTCQ in a predictive coding structure. Extensions of the approach treat uniform and vector codebooks.

关键词： QUANTIZATION trellis coding ENTROPY SOURCE coding RATE DISTORTION FUNCTION

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IMPORTANCE SAMPLING FOR TCM SCHEME OVER NON-GAUSSIAN NOISE CHANNEL

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IEICE TRANSACTIONS ON FUNDAMENTALS OF ELECTRONICS COMMUNICATIONS AND COMPUTER SCIENCES 1995年第9期E78A卷 1109-1116页

作者： SAKAI, T OGIWARA, H Nagaoka Univ of Technology Nagaoka-shi Japan

When bit error probability of a trellis-coded modulation (TCM) scheme becomes very small, it is almost impossible to evaluate it by an ordinary Monte-Carlo simulation method. Importance sampling is a technique of reducing the number of simulation samples required. The reduction is attained by modifying the noise to produce more errors. The low error rate can be effectively estimated by applying importance sampling. Each simulation run simulates a single error event, and importance sampling is used to make the error events more frequent. The previous design method of the probability density function in importance sampling is not suitable for the TCM scheme on an additive non-Gaussian noise channel. The main problem is how to design the probability density function of the noise used in the simulation. We propose a new design method of the simulation probability density function related to the Bhattacharyya bound. It is reduced to the same simulation probability density function of the old method when the noise is additive white Gaussian. By using the proposed method for an additive non-Gaussian noise, the reduction of simulation time is about 1/170 at bit error rate of 10(-6) if the overhead of the calculation of the Bhattacharyya bound is ignored. Under the same condition, the reduction of the simulation time by the proposed method is 1/65 of the ordinary Monte-Carlo method even if we take the overhead for importance sampling into account.

关键词： IMPORTANCE SAMPLING MONTE-CARLO SIMULATION trellis coding CODED MODULATION NON-GAUSSIAN NOISE

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Blind equalization of quadrature partial response-trellis coded modulated signals in Rician fading

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INTERNATIONAL JOURNAL OF SATELLITE COMMUNICATIONS 2001年第2期19卷 159-168页

作者： Cirpan, HA Ucan, ON Univ Istanbul Dept Elect Engn TR-34850 Istanbul Turkey

In this paper, a blind maximum-likelihood channel estimation algorithm is developed for quadrature partial response-trellis coded modulated (QPR-TCM) signals propagating through a Rician fading environment. A hidden Markov model (HMM) formulation of the problem is introduced and the Baum-Welch parameter estimation algorithm is modified to provide a computationally efficient solution to the resulting optimization problem. Performance analysis of the proposed method is carried out through the evaluation of bit-error probability upper bound for Rician fading channels. Also, some illustrative simulations are presented. Copyright (C) 2001 John Wiley & Sons, Ltd.

关键词： channel equalization channel estimation Rician fading trellis coding

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trellis-CODED DIRECT-SEQUENCE SPREAD-SPECTRUM COMMUNICATIONS

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IEEE TRANSACTIONS ON COMMUNICATIONS 1994年第12期42卷 3161-3170页

作者： WOERNER, BD STARK, WE UNIV MICHIGAN DEPT ELECT ENGN & COMP SCI ANN ARBOR MI 48109 USA

This paper considers the application of trellis coding techniques to direct-sequence spread-spectrum multiple-access (DS/SSMA) communication. The unique feature of the trellis codes considered is that they are constructed over the set of possible signature sequences rather than over some standard 2-D signal constellation. The resulting codes have a small number of signals per dimension. We present several examples of these trellis codes, and suggest possible methods of implementation. We also present a detailed error analysis for this system, which employs techniques developed by Lehnert and Pursley to accurately model the multiple access interference. We generate numerical results for several examples and conclude that the proposed trellis coded systems yield significant performance improvements over binary antipodal DS/SSMA systems. In addition, the new trellis codes perform better than standard error control techniques with the same complexity and code rate. Analytic results are verified with simulations.

关键词： .MPSK trellis codes numerical results signal set Direct-Sequence Spread-Spectrum binary antipodal trellis coding Boudreau and Falconer

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Application of turbo TCM codes for impulsive noise channel

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IEICE TRANSACTIONS ON FUNDAMENTALS OF ELECTRONICS COMMUNICATIONS AND COMPUTER SCIENCES 1998年第10期E81A卷 2032-2039页

作者： Koike, K Ogiwara, H Nagaoka Univ Technol Fac Engn Nagaoka Niigata 9402188 Japan

A turbo TCM system is applied to a channel with overall noise which is equal to the additive combination of impulsive Gaussian noise and Additive White Gaussian Noise (AWGN). By taking the distribution of the previously mentioned overall noise into account, a decoding algorithm for Poisson occurrence impulsive noise is derived as an extension of that for AWGN. A simulation result shows that E-b/N-0 difference from Shannon limit to realize BER=10(-4) is 0.493 dB. To investigate the effect of burst noise, we discuss the case of additive impulsive noise with Markovian occurrence which is represented by Hidden Markov Model. A decoding algorithm for Markovian noise is proposed. In the iterative decoding for the Markovian channel, the decoding algorithms for Markovian and Poisson noise are applied separately to the two component decoders. The decoding algorithm for Markovian noise is used in the component decoder wherein received signal is directly fed, while the decoding algorithm for Poisson noise is used in the component decoder wherein received signal is fed after passing an interleaver. This paper also shows simulation results that include the effects of varying the noise parameters in the decoding. In the Markovian case, when smaller value of variance of impulsive noise is used, the observed flattening of BER performance is more serious compared to the effect in the Poisson noise channel. No flattening is observed when large value is used.

关键词： turbo codes trellis coding coded modulation impulsive noise

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CEC: Cluster Embedding coding for H.264 Steganography

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IEEE SIGNAL PROCESSING LETTERS 2020年 27卷 955-959页

作者： Wang, Yu Cao, Yun Zhao, Xianfeng Chinese Acad Sci Inst Informat Engn State Key Lab Informat Secur Beijing 100195 Peoples R China Univ Chinese Acad Sci Sch Cyber Secur Beijing 100195 Peoples R China

In this letter, we first propose a novel coding method to design content-adaptive H.264 steganography with quantized discrete cosine transform (QDCT) coefficients. Currently, the state-of-the-art steganographic methods minimize a heuristically defined distortion function using STCs and embed messages in a pixel-wise manner. When this concept is directly applied to H.264 steganographic designing, there are two factors that hinder the improvement of empirical security: interaction of embedding changes, and the block-wise characteristics of video compression. Our proposed CEC scheme performs both message embedding and video compression in the block-wise manner where a cluster of elements in a cover block are modified simultaneously, and defines a joint distortion function on the cover block to reflect the features of rate-distortion optimization. Experimental results demonstrate the effectiveness of our proposed coding method.

关键词： Distortion Encoding Additives Aggregates Rate-distortion Convolutional codes Video compression Cluster embedding joint distortion trellis coding video steganography

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