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IEEE International Symposium on Circuits and Systems

作者： Chokchaitam, S Iwahashi, M Nagaoka Univ Technol Dept Elect Engn Nagaoka Niigata 9402188 Japan

ISBN: (纸本)0780374487

In this report, we propose lossless/lossy coding gain as a new objective criterion to theoretically evaluate lossless and lossy coding performance of the lossless/lossy wavelet (LLW). The proposed lossless/lossy coding gain consists of three parameters: "lossless coding gain", "quantization-lossy coding gain" and "rounding errors". Performances of 15 kinds of the LLW are measured with two-dimensional (2D) octave-decomposition. Some standard images are applied as input signals to evaluate coding performance of the LLW.

关键词： lossless lossy wavelet coding gain rounding error evaluation

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ON THE coding gain OF INTRA-PREDICTIVE TRANSFORMS

ON THE CODING GAIN OF INTRA-PREDICTIVE TRANSFORMS

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16th IEEE International Conference on Image Processing

作者： Xu, Jizheng Wu, Feng Zhang, Wenjun Shanghai Jiao Tong Univ Dept Elect Engn Inst Image Commun & Informat Proc Shanghai Peoples R China Shanghai Jiao Tong Univ Shanghai Key Lab Digital Media Processing & Trans Shanghai Peoples R China Microsoft Res Asia Beijing Peoples R China

ISBN: (纸本)9781424456536

Intra-predictive transforms are a kind of block-based transforms that can exploit both the intra- and inter-block correlations. This paper analyzes the coding gains of intra-predictive transforms for the Gaussian process. The tight upper bound of the coding gain is derived, which is shown to be better than both the discrete cosine transform and the Karhunen Loeve transform. The optimal intra-predictive transform that achieves the upper bound is also presented. Actual coding results on images verify the effectiveness of the optimal intra-predictive transform.

关键词： Image coding intra-predictive transform coding gain

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ON THE coding gain OF SEPARABLE 2D WAVELET FILTER BANKS

ON THE CODING GAIN OF SEPARABLE 2D WAVELET FILTER BANKS

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15th IEEE International Conference on Image Processing (ICIP 2008)

作者： Adams, Michael D. Univ Victoria Dept Elect & Comp Engn Victoria BC V8W 3P6 Canada

ISBN: (纸本)9781424417650

It has been observed that filter banks from a certain popular separable 2D wavelet class always appear to have a higher coding gain with respect to a separable image model than with respect to an isotropic one. This behavior is examined in detail and an explanation for it is offered. As it turns out, for such filter banks, it is highly improbable (if not impossible) for the isotropic coding gain to exceed the separable coding gain.

关键词： image coding wavelet transforms filter banks coding gain separable/isotropic image models

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Non-Orthogonal STBC for Four Transmit Antennas with High coding gain and Low Decoding Complexity

Non-Orthogonal STBC for Four Transmit Antennas with High Cod...

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5th International Conference on Signal Processing and Communication Systems (ICSPCS)

作者： Sharma, Nidhi Bhatnagar, Manav R. Agrawal, Monika Indian Inst Technol Delhi Dept Elect Engn New Delhi 110016 India Indian Inst Technol Delhi Ctr Appl Res Elect New Delhi 110016 India

ISBN: (纸本)9781457711800

Multiple antenna based technology enhances performance of communication system by increasing capacity and reliable detection of the transmitted data. Space-time block codes (STBCs) for multiple-input multiple-output (MIMO) systems are designed to achieve full diversity when transmitter does not have channel state information. Orthogonal space-time block codes (OSTBCs) provide symbol-wise decoding, while quasi orthogonal STBCs are used to achieve high data rates with pair-wise decoding complexity. However, most of the existing OSTBCs and QOSTBCs utilize repeated transmission of symbols which reduces capacity of the wireless communication system. In this paper, we propose a non-orthogonal STBC for four transmit antennas that avoids repeated transmission of symbols. The proposed code transmits optimally mapped symbols in place of repeated transmissions of a symbol. The proposed STBC provides improved capacity and significant coding gain as compared to the existing STBCs for four transmit antennas. We also derive a low-complexity decoder of the proposed STBC which performs close to the maximum likelihood decoder.

关键词： transmitting antennas coding gain Wireless communication systems Signs and symbols non-orthogonal DEcoding

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A method for estimating coding gain of an orthogonal wavelet transform considering higher-order statistics

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ELECTRONICS AND COMMUNICATIONS IN JAPAN PART III-FUNDAMENTAL ELECTRONIC SCIENCE 1999年第1期82卷 58-67页

作者： Yokota, Y Usui, S Gifu Univ Fac Engn Dept Elect & Comp Engn Gifu 50111 Japan Toyohashi Univ Technol Dept Informat & Comp Sci Toyohashi Aichi 441 Japan

In applications such as subband coding, the coding gain is a useful evaluation measure for representing the bit-rate reduction performance of the subband filter for the object of coding. It is widely used in the estimation of coding performance and the design of subband filters. To estimate the coding gain requires knowledge of the probability density distribution of the object of coding and the decomposed subband series. Identification of the probability density function, however, is in general difficult. Consequently an approximation is often used in the estimation of the coding gain, where it is assumed that the probability density distributions of the object of coding and all subband series are the same. Thus, estimation of the coding gain contains an error for data, such as images, where this assumption is not satisfied. This paper notes that the probability density distribution of the subband decomposed image can be well approximated by a generalized Gaussian distribution and proposes a method for a more accurate estimation of the coding gain in the orthogonal wavelet transform attained by a variety of subband filter, using the higher-order statistics of the object of coding. The coding gain is estimated for several objects of coding. Comparing the result to the actually measured value, it is shown that the accuracy of estimation is greatly improved in the proposed method, compared to the method based on an approximation. (C) 1998 Scripta Technica.

关键词： subband coding orthogonal wavelet transform coding gain higher-order statistics generalized Gaussian distribution

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A study on estimating coding gain of pyramid-type non-orthogonal subband filters

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ELECTRONICS AND COMMUNICATIONS IN JAPAN PART III-FUNDAMENTAL ELECTRONIC SCIENCE 1999年第1期82卷 51-57页

作者： Yokota, Y Iwata, A Yoshida, Y Nagoya Inst Technol Dept Elect & Comp Engn Nagoya Aichi 466 Japan MITEC Inc Tokyo 135 Japan

In coding intended for nonreciprocal information compression, it is required to attain a high compression rate and minimized error of the restored signal. The coding gain is the rate of error reduction when the bit error rate is kept constant before and after applying orthonormal transform, such as the discrete cosine transform or orthogonal wavelet transform. This has been used as a quantitative measure of coding performance. On the other hand, the coding gain has been similarly formulated even in non-orthogonal subband coding such as is used for the design of subband filters and for the determination of the optimum distribution of quantization error in each subband. In this paper, we point out that an approximation is included in the coding gain estimation equation for the pyramidal non-orthogonal subband filters used to date. By comparing the estimated coding gains with and without the approximation, the coding gain estimation error produced by the approximation is evaluated. For the pyramidal subband filter based on SSKF, the estimated error of the coding gain produced by the approximation is about 0.1 dB. (C) 1998 Scripta Technica.

关键词： subband coding pyramidal nonorthogonal subband filter coding gain optimum quantization error distribution

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ON THE coding gain OF INTRA-PREDICTIVE TRANSFORMS

ON THE CODING GAIN OF INTRA-PREDICTIVE TRANSFORMS

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International Conference on Image Processing

作者： Jizheng XU Feng WU Wenjun ZHANG Institute of Image Communication and Information Processing Department of Electronic Engineering Shanghai Jiao Tong University Microsoft Research Asia

ISBN: (纸本)9781424456536;9781424456543

关键词： Image coding Intra-predictive transform coding gain coding gain image coding Transform Upper bound gain discrete cosine transforms

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Maximizing coding gain in Wireless Networks with Decodable Network coding

Maximizing Coding Gain in Wireless Networks with Decodable N...

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Ad-Hoc and Sensor Networks Symposium

作者： Maggie Cheng Quanmin Ye Xiaochun Cheng Lin Cai Missouri University of Science and Technology Computer Science Department Nokia Networks Middlesex University Computer Science Department University of Victoria Electrical and Computer Engineering Department

ISBN: (纸本)9781479966653

Network coding improves transmission efficiency by combining packets at relay nodes and thus reduces the number of packets sent to the network. It is a network layer solution to improve network throughput and transmission efficiency. However, a coded packet must be decodable by the destination, otherwise it is a waste of resource to combine them together and to deliver the coded packet. This paper addresses how to find the coding solution that guarantees decodability at the destination. We first quantify the coding gain as the number of transmissions reduced, and then provide a method for runtime check whether a coding pair can be separated at the destination. The optimal coding solution is selected as the one that provides the maximum coding gain among all the decodable pairs. The algorithms can be applied to both unicast and multicast traffic. Simulation results show the number of transmissions can be reduced significantly, especially for multicast traffic where there are rich opportunities to apply network coding.

关键词： coding gain Network coding transmission efficiency Wireless networks Packet destination Unicast Network throughput Runtime Transmissions transmission

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MULTIPURPOSE HIGH-coding-gain 0.8-UPSILON-M BICMOS VLSIS FOR HIGH-SPEED MULTILEVEL TRELLIS-CODED MODULATION

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IEEE JOURNAL OF SOLID-STATE CIRCUITS 1991年第11期26卷 1700-1707页

作者： AIKAWA, S NAKAMURA, Y TAKANASHI, H NIPPON TELEGRAPH & TEL PUBL CORP NETWORK ENGN HEADQUARTER CHIYODA KU TOKYO 100 JAPAN NIPPON TELEGRAPH & TEL PUBL CORP YOKOSUKA ELECT COMMUN LABS RADIO COMMUN SYST LABS YOKOSUKA KANAGAWA 23803 JAPAN

Multilevel trellis-coded QAM VLSI's were designed and developed. These VLSI's realize a coding gain of 7.9 dB with SPORT-256QAM. The VLSI's contain an encoder, mapper, and decoder for trellis-coded 16, 32, 64, 128, and 256QAM utilizing general mapping. Using small-size and low-power path memory, 150K gates are achieved using two chips with die sizes of 8 x 11 and 14 x 14 mm2. The VLSI's achieve a maximum data throughput rate of 17 MBd (guaranteed), 30 MBd (typical), and dissipate only 1 W at a data rate of 17 MBd. The VLSI's also contain a phase ambiguity rejection circuit for a recovered carrier and error pulse generator. The devices are designed with a BiCMOS 0.8-mu-m process rule. The experimental result of bit-error-rate (BER) performance is presented. The developed VLSI's are effective for outage-free digital microwave radio systems.

关键词： trellis coded modulation Trellis codes decoders coding gain multilayers BiCMOS Quadrature amplitude modulation small size Data transfer rates

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Increasing of coding gain of Soft Input Soft Output Channel Decoding

Increasing of Coding Gain of Soft Input Soft Output Channel ...

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IEEE Mediterranean Electrotechnical Conference

作者： Natasa Zivic Institute for Data Communication Systems University of Siegen

ISBN: (纸本)9781467307826

The subject of this paper is combining of Soft Input Soft Output (SISO) channel decoding and cryptographic mechanisms with some of well known procedures used in communication systems, such as interleaving, puncturing and bit stuffing. The algorithm is proposed, which enables improvement of used channel decoding by interleaving of bits known to the transmitter and the receiver, resulting in additional overall coding gain.

关键词： coding gain Channel Decoder transmitter receivers COMMUNICATION SYSTEMS Drill bits

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