检索结果-内蒙古大学图书馆

A binary block concatenated code based on two convolutional codes

Electronic Notes in Discrete Mathematics 2017年 57卷 219-224页

作者： Zhilin, Igor Zyablov, Victor Zigangirov, Dmitry Lab. #3 Institute for Information Transmission Problems of the Russian Academy of Sciences (Kharkevich Institute) Moscow Russian Federation

关键词： active distance concatenated code convolutional code free distance minimum distance

来源：评论

学校读者我要写书评

暂无评论

Simultaneous code/Error-Trellis Reduction for convolutional codes Using Shifted code/Error-Subsequences

Simultaneous Code/Error-Trellis Reduction for Convolutional ...

引用

IEEE International Symposium on Information Theory (ISIT)

作者： Tajima, Masato Okino, Koji Miyagoshi, Takashi Toyama Univ Grad Sch Sci & Engn 3190 Gofuku Toyama 9308555 Japan Toyama Univ Informat Engn Technol 3190 Gofuku Toyama 9308555 Japan

ISBN: (纸本)9781457705953

In this paper, we show that the code-trellis and the error-trellis for a convolutional code can be reduced simultaneously, if reduction is possible. Assume that the error-trellis can be reduced by shifting particular error-subsequences. In this case, if the identical shifts occur in the corresponding subsequences of each code path, then the code-trellis can also be reduced. First, we obtain pairs of transformations which generate the identical shifts both in the subsequences of the code-path and in those of the error-path. Next, by applying these transformations to the generator matrix and the parity-check matrix, we show that reduction of these matrices is accomplished simultaneously, if it is possible. Moreover, it is shown that the two associated trellises are also reduced simultaneously.

关键词： Complexity theory convolutional codes Decoding Educational institutions Electronic mail Generators Parity check codes code path code-error-trellis reduction convolutional code convolutional codes error path generator matrix matrices reduction matrix algebra parity check codes parity check matrix particular error-subsequence shifted code-error-subsequence trellis codes

来源：评论

学校读者我要写书评

暂无评论

convolutional codes and coherent sheaves

引用

APPLICABLE ALGEBRA IN ENGINEERING COMMUNICATION AND COMPUTING 2001年第4期12卷 273-326页

作者： Lomadze, V Math Inst GE-380093 Tbilisi Georgia

We present a sheaf-theoretic setting for convolutional codes in that coherent sheaves (over a projective line) play the same role as finite-dimensional linear spaces in the theory of block codes. Using coherent sheaves (and their cohomologies), we give natural straightforward proofs of the main results on the structural properties of convolutional codes.

关键词： module linear space sheaf exact sequence cohomology convolutional code convolutional encoder complexity observability noncatastrophicity linear sequential circuit formal language Hilbert function

来源：评论

学校读者我要写书评

暂无评论

A convolutional codeD ARQ SCHEME WITH RETRANSMISSION CRITERION BASED ON AN ESTIMATED DECODING ERROR RATE

引用

IEICE TRANSACTIONS ON FUNDAMENTALS OF ELECTRONICS COMMUNICATIONS AND COMPUTER SCIENCES 1995年第1期E78A卷 100-110页

作者： FUJIWARA, H YAMAMOTO, H REN, JQ Univ of Electro-Communications Chofu-shi Japan

A new Hybrid-ARQ scheme with a convolutional code and the Viterbi decoding is proposed, which uses the packet combining technique and a retransmission criterion based on an estimated decoding error rate. The throughput and bit error rate are evaluated by theoretical bounds and computer simulations. It is shown that a given error rate tolerance can be attained with good throughput for any signal to noise ratio, i.e. for the slow time-varying channels. Furthermore, the throughput performance can be improved by retransmitting not all but a part of packet.

关键词： ARQ convolutional code VITERBI DECODING PACKET COMBINING

来源：评论

学校读者我要写书评

暂无评论

convolutional codes in Two-Way Relay Networks with Physical-Layer Network Coding

引用

IEEE TRANSACTIONS ON WIRELESS COMMUNICATIONS 2010年第9期9卷 2724-2729页

作者： To, Duc Choi, Jinho Swansea Univ Sch Engn Swansea W Glam Wales

We study the application of convolutional codes to two-way relay networks (TWRNs) with physical-layer network coding (PNC). When a relay node decodes coded signals transmitted by two source nodes simultaneously, we show that the Viterbi algorithm (VA) can be used by approximating the maximum likelihood (ML) decoding for XORed messages as two-user decoding. In this setup, for given memory length constraint, the two source nodes can choose the same convolutional code that has the largest free distance in order to maximize the performance. Motivated from the fact that the relay node only needs to decode XORed messages, a low complexity decoding scheme is proposed using a reduced-state trellis. We show that the reduced-state decoding can achieve the same diversity gain as the full-state decoding for fading channels.

关键词： Two-way relay network physical-layer network coding (PNC) multiple access channel convolutional code Viterbi algorithm

来源：评论

学校读者我要写书评

暂无评论

convolutional codes in Two-Way Relay Networks with Rate Diverse Network Coding

Convolutional Codes in Two-Way Relay Networks with Rate Dive...

引用

World Congress on Information and Communication Technologies (WICT)

作者： Cheng, Ping Hao, Jianjun Guo, Yijun Beijing Univ Posts & Telecommun Beijing Key Lab Network Syst Architecture & Conve Beijing 100088 Peoples R China

ISBN: (纸本)9781467348041

In two-way relay networks (TWRNs) with physical-layer network coding (PNC), introduction of convolutional codes is able to enhance the overall system reliability. In addition, the relay node has to determine a particular broadcast rate for coded packets transmission as the selected rate should be supported on the worst quality links to the intended receivers. Thus, the throughput gain brought by network coding is limited by capacity of the worst link in TWRNs. In this paper, a novel symbol-level rate diverse network coding (RDNC) scheme and reduced-state decoding scheme for convolutional codes are proposed to address the two problems. In this setup, for a given memory length constraint, two source nodes can adopt convolutional codes of different lengths and use reduced-state trellis to reduce decoding complexity. In this work, it is shown that the proposed approach is able to improve system throughput significantly, offer increased reliability, and reduce the complexity of convolutional codes decoding at the same time.

关键词： Two-way relay network physical-layer network coding rate diverse network coding multiple access channel convolutional code Viterbi algorithm rate-diverse broadcast wireless link quality

来源：评论

学校读者我要写书评

暂无评论

Iterative joint channel decoding of correlated sources employing serially concatenated convolutional codes

引用

IEEE TRANSACTIONS ON INFORMATION THEORY 2005年第7期51卷 2721-2731页

作者： Daneshgaran, F Laddomada, M Mondin, M Calif State Univ Los Angeles Dept Elect & Comp Engn Los Angeles CA 90032 USA Politecn Torino Dipartimento Elettron I-10129 Turin Italy

This correspondence looks at the problem of joint decoding of serially concatenated convolutional codes (SCCCs) used for channel coding of multiple correlated sources. We assume a simple model whereby two correlated sources transmit SCCC encoded data to a single destination receiver. We do not assume the existence of, nor do we use channel side information at the receiver. In particular, we present a novel iterative joint channel decoding algorithm for correlated sources by using the empirical cross-correlation measurements at successive decoding iterations to provide extrinsic information to the outer codes of the SCCC configuration. Two levels of soft metric iterative decoding are used at the receiver: 1) iterative maximum a posteriori probability (MAP) decoding is used for efficient decoding of individual SCCC codes (local iterations) and 2) iterative extrinsic information feedback generated from the estimates of the empirical cross correlation in partial decoding steps is used to pass soft information to the outer decoders of the global joint SCCC decoder (global iterations). We provide analytical results followed by simulation studies confirming the robustness of the cross-correlation estimates to channel-induced errors, justifying the use of such estimates in iterative decoding. Experimental results suggest that relatively few global iterations (two to five) during which multiple local iterations are conducted are sufficient to reap significant gains using this approach specially when the sources are highly correlated.

关键词： concatenated codes convolutional code correlated sources iterative decoding joint decoding serially concatenated codes Slepian-Wolf soft decoding turbo codes

来源：评论

学校读者我要写书评

暂无评论

Construction of High-Rate convolutional codes Using Dual codes*

引用

IEICE TRANSACTIONS ON FUNDAMENTALS OF ELECTRONICS COMMUNICATIONS AND COMPUTER SCIENCES 2023年第3期E106A卷 375-381页

作者： Moriya, Sen Sasano, Hiroshi Kindai Univ Fac Sci & Engn Higashiosaka 5778502 Japan Kindai Univ Cyber Informat Res Inst Higashiosaka 5778502 Japan

In this study, we consider techniques for searching high -rate convolutional code (CC) encoders using dual code encoders. A low-rate (R = 1/n) CC is a dual code to a high-rate (R = (n - 1)/n) CC. According to our past studies, if a CC encoder has a high performance, a dual code encoder to the CC also tends to have a good performance. However, it is not guaranteed to have the highest performance. We consider a method to obtain a high-rate CC encoder with a high performance using good dual code encoders, namely, high-performance low-rate CC encoders. We also present some CC encoders obtained by searches using our method.

关键词： convolutional code dual code weight spectrum

来源：评论

学校读者我要写书评

暂无评论

A Trace-Back Method with Source States for Viterbi Decoding of Rate-1/n convolutional codes

引用

IEICE TRANSACTIONS ON FUNDAMENTALS OF ELECTRONICS COMMUNICATIONS AND COMPUTER SCIENCES 2012年第4期E95A卷 767-775页

作者： Ito, Kazuhito Saitama Univ Grad Sch Sci & Engn Saitama 3388570 Japan

The Viterbi algorithm is widely used for decoding of the convolutional codes. The trace-back method is preferable to the register exchange method because of lower power consumption especially for convolutional codes with many states. A drawback of the conventional trace-back is that it generally requires long latency to obtain the decoded data. In this paper, a method of the trace-back with source states instead of decision bits is proposed which reduces the number of memory accesses. The dedicated memory is also presented which supports the proposed trace-back method. The reduced memory accesses result in smaller power consumption and a shorer decode latency than the conventional method.

关键词： Viterbi decoder convolutional code trace back survivor memory low power

来源：评论

学校读者我要写书评

暂无评论

Decoding of High Rate convolutional codes Using the Dual Trellis

引用

IEEE TRANSACTIONS ON INFORMATION THEORY 2010年第1期56卷 273-295页

作者： Srinivasan, Sudharshan Pietrobon, Steven S. Univ S Australia ITR Mawson Lakes SA 5095 Australia Small World Commun Payneham S SA 5070 Australia

This paper deals with a posteriori probability (APP) decoding of high-rate convolutional codes, using the dual code's trellis. After deriving the dual APP (DAPP) algorithm from the APP relation, its trellis-based implementation is addressed. The challenge involved in practical implementation of a DAPP decoder is then highlighted. Metric representation schemes similar to the log domain used for log-APP decoding are shown to be unattractive for DAPP decoding due to quantization requirements. After explaining the nature of the DAPP metrics, an arc hyperbolic tangent (AHT) scheme is proposed and its equivalent arithmetic operations derived. By using an efficient approximation, an addition is translated to an addition in the AHT domain. Efficient techniques for normalization and extrinsic log-likelihood ratio (LLR) calculation are presented which reduce implementation complexity significantly. Simulation results with different high-rate codes are given to show that the AHT-DAPP decoder performs similarly to a log-APP decoder and at the same time performs better than a decoder for a punctured code. A fully fixed-point model of an AHT-DAPP decoder is shown to perform close to an optimum decoder. The decoding complexity of the log-APP and AHT-DAPP decoders are listed and compared for several rate-k/(k+1) codes. It is shown that an AHT-DAPP decoder starts to be less complex from a code rate of 7/8. When compared against a max-log-APP decoder, the AHT-DAPP decoder is less complex at a code rate of 9/10 and above.

关键词： Arc hyperbolic tangent (AHT) a posteriori probability (APP) complexity convolutional code dual code fixed point high rate implementation maximum a posteriori probability (MAP) decoder

来源：评论

学校读者我要写书评

暂无评论

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

请选择保存的检索档案：

请选择收藏分类：

通借通还

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：