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2001 International Conferences on Info-tech and Info-net

作者： Guixia Kang Xianglan Jin Qingyi Quan Ping Zhang Beijing Univ.of Posts and Telecommunications

This paper discusses the decision issue on the concatenation of space-time block code and convolutional code in WCDMA *** compare the performance of three decision schemes,i.e.,hard-decision,uniform quantization(UQ) soft-decision and adaptive uniform quantization(AUQ) soft-decision over Rayleigh fading *** results show that both soft-decision schemes have obviously gain over 1dB than ***,if we divide the Rayleigh fading item from the output of space-time block combining,a little more performance gain is possible,thus reaches the soft-decision advantage about 2dB than *** because the AUQ scheme changes its quantization scope according to the signal-noise-ratio(SNR),it has extra performance advantage over UQ scheme in fading channel especially at very high or low ***,all of the performance gain is based on increasing the hardware implementation complexity.

关键词： Diversity fading channel space-time code convolutional code concatenation decision wireless communication

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convolutional-code-Specific CRC code Design

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IEEE TRANSACTIONS ON COMMUNICATIONS 2015年第10期63卷 3459-3470页

作者： Lou, Chung-Yu Daneshrad, Babak Wesel, Richard D. Univ Calif Los Angeles Dept Elect Engn Los Angeles CA 90095 USA

Cyclic redundancy check (CRC) codes check if a codeword is correctly received. This paper presents an algorithm to design CRC codes that are optimized for the code-specific error behavior of a specified feedforward convolutional code. The algorithm utilizes two distinct approaches to computing undetected error probability of a CRC code used with a specific convolutional code. The first approach enumerates the error patterns of the convolutional code and tests if each of them is detectable. The second approach reduces complexity significantly by exploiting the equivalence of the undetected error probability to the frame error rate of an equivalent catastrophic convolutional code. The error events of the equivalent convolutional code are exactly the undetectable errors for the original concatenation of CRC and convolutional codes. This simplifies the computation because error patterns do not need to be individually checked for detectability. As an example, we optimize CRC codes for a commonly used 64-state convolutional code for information length k = 1024, demonstrating significant reduction in undetected error probability compared to the existing CRC codes with the same degrees. For a fixed target undetected error probability, the optimized CRC codes typically require 2 fewer bits.

关键词： Catastrophic code convolutional code cyclic redundancy check (CRC) code undetected error probability

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Extension of coefficients for (n, k, m) convolutional-code-based packet loss recovery

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COMPUTERS & MATHEMATICS WITH APPLICATIONS 2006年第2期51卷 247-256页

作者： Arai, M Fukumoto, S Iwasaki, K Tokyo Metropolitan Univ Grad Sch Engn Hachioji Tokyo 1920397 Japan

This paper discusses a new idea for improving the recovery of (n, k, m) convolutional-code-based packet-level FEC. We extend the coefficients in the generator matrix to the elements on GF(2(8)). Each byte in the redundant packets is generated independently, assuming the bytes are the elements on GF(2(8)). The postreconstruction receiving rate is analytically derived from the necessary conditions for recovery. Moreover, the ability to recover lost packets is estimated based on analysis, and we demonstrate that the extension of coefficients improves the number of recovered packets more than the conventional method where coefficients are 0 or 1. (c) 2005 Elsevier Ltd. All rights reserved.

关键词： convolutional code forward error correction packet loss recovery postreconstruction receiving rate

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Evaluation of convolutional-code-based FEC under limited recovery time and its application to real-time transmission

Evaluation of convolutional-code-based FEC under limited rec...

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9th Pacific Rim International Symposium on Dependable Computing

作者： Arai, M Kurosu, H Fukumoto, S Iwasaki, K Tokyo Metropolitan Univ Grad Sch Engn Tokyo 1920397 Japan

ISBN: (纸本)0769518524

In this paper we evaluate the effectiveness of the use of convolutional codes under a time limit for recovery as a method for packet loss recovery. We analyze the method's operation when a limitation on the number of received packets is substituted for the time limitation, and derive the probability for a lost packet being recovered before the arrival of the limiting number of succeeding packets. We also evaluate this probability in the results of simulation and estimate the buffer size required for a decoder Moreover we apply this method in constructing a dependable video-conference system and observe the resulting improvement in QoS.

关键词： convolutional code packet loss forward error correction dependable video conference H. 323

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Extension of coefficients for (n, k, m) convolutional-code-based packet loss recovery

Extension of coefficients for (n, k, m)...

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2nd Euro-Japanese Workshop on Stochastic Modelling for Finance Insurance Production and Reliability

作者： Arai, M Fukumoto, S Iwasaki, K Tokyo Metropolitan Univ Grad Sch Engn Hachioji Tokyo 1920397 Japan

关键词： convolutional code forward error correction packet loss recovery postreconstruction receiving rate

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New Tighter Upper Bounds on the Performance of convolutional code over Exponentially Correlated Rayleigh Fading channel

New Tighter Upper Bounds on the Performance of convolutional...

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International Wireless Communications and Mobile Computing Conference

作者： Yassine Mouchtak Faissal El Bouanani ENSIAS Mohammed V University in Rabat

ISBN: (纸本)9781509003051

This paper presents tighter bounds on the pairwise error-event probability and therefore very tighter upper bounds of bit error rate (BER) for communication systems employing convolutional code over Rayleigh fading channel with exponential correlation coefficient. To obtain our bound, we start by proposing a closed form upper bound for Gaussian Q-function and as well as deriving a new lower bound of each channel covariance matrix eigenvalue. The simulation results show that our proposed bound is tighter than those previously developed, especially when the covariance parameter q increases. A gain of over 6.5dB was achieved for q = 0.95 at BER=10~(-5) from the better previous bound, whereas for the lower values of q we reach the simulated curve.

关键词： Performance Upper Bound Analysis convolutional code Correlated Rayleigh Fading Channel Bit Error Rate Q-Function

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Joint Frame Synchronization and CCSDS convolutional code Identification Based on Correlation of codeword

Joint Frame Synchronization and CCSDS Convolutional Code Ide...

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2015 Fifth International Conference on Instrumentation and Measurement,Computer,Communication and Control (IMCCC2015)(第五届仪器测量、计算机通信与控制国际会议)

作者： Xue Li Xiujuan Yao Chunmei Wang Department of Test Technology Researching National Space Science Center CAS Beijing P. R. China

ISBN: (纸本)9781467377249

In this paper,the problems involving frame synchronization and convolutional code identification for CCSDS link protocol are *** combining the correlation of convolutional codeword and the theory of association rule mining,a new joint frame synchronization and code identification method is *** uses sequence position association to identify periodic frequent sequences and then match them with the prior knowledge of convolutional encoded CCSDS *** method realizes the convolutional code identification and frame synchronization without the information of codeword starting point,the codeblock length and code *** analysis and simulation results demonstrate that this method can detect the code rate of CCSDS Link Protocol standard and achieve frame synchronization within a certain error rate range.

关键词： frame synchronization code identification convolutional code association rules CCSDS link protocol

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New Bounds for Generalized Column Distances and Construction of convolutional codes

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IEEE TRANSACTIONS ON INFORMATION THEORY 2025年第4期71卷 2576-2590页

作者： Pan, Xu Chen, Hao Tang, Chunming Chen, Xueyan Jinan Univ Coll Informat Sci & Technol Cyber Secur Guangzhou 510632 Guangdong Peoples R China Jinan Univ Coll Informat Sci & Technol Guangzhou 510632 Guangdong Peoples R China Guangzhou Univ Sch Math & Informat Sci Guangzhou 510006 Guangdong Peoples R China Cent China Normal Univ Sch Math & Stat Wuhan 430079 Hubei Peoples R China

Based on known bounds for relative generalized Hamming weights of linear codes, we provide several new bounds for generalized column distances of convolutional codes, including the Griesmer-type bound for generalized column distances. Then we construct several infinite families of convolutional codes such that the (1, 1)-Griesmer defect of these convolutional codes is small compared with the length of these convolutional codes by using cyclic codes, negacyclic codes and GRS codes. In particular, we obtain some convolutional codes such that the (1, 1)-Griesmer defect of these convolutional codes is zero or one. Next we prove that the 2-generalized column distance sequence {d(2,j)(C)}(infinity)(j=1)of any convolutional code C is increasing and bounded from above, and the limit of the sequence {d(2,j)(C)}(infinity)(j=1 )is related to the2-generalized Hamming weight of the convolutional code C. For i >= 3, we prove that the i-generalized column distance sequence {d(i,j)(C)}(infinity)(j=Gamma i/k-1 )of any convolutional code C is bounded above and below.

关键词： convolutional codes Hamming weight Generators codecs Electronic mail Linear codes Hamming distances Vectors Training Polynomials convolutional code relative generalized Hamming weight generalized Hamming weight generalized column distance Griesmer-type bound

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76.5-Gb/s Viterbi Decoder for convolutional codes on GPU

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IEEE EMBEDDED SYSTEMS LETTERS 2025年第1期17卷 22-25页

作者： Liu, Zhanxian Liu, Chufan Zhang, Haijun Zhao, Ling Univ Sci & Technol Beijing Sch Comp & Commun Engn Beijing 100083 Peoples R China Beihang Univ Sch Elect & Informat Engn Beijing 100191 Peoples R China

This letter presents an optimized Viterbi decoder of convolutional codes on graphics processing unit (GPU) for software defined radio (SDR) platforms. Before the forward process, channel messages are interleaved with coalesced global memory access and the interleaved messages are represented with 4 bits to improve shared memory efficiency. Moreover, we optimize on-chip memory allocations of the forward process to accelerate instruction execution. Excluding the data transfer latency between host and device, the proposed Viterbi decoder achieves 22.2 and 76.5-Gb/s throughput on Tesla V100 and RTX4090, respectively. Compared with related works, the throughput speedups achieved by the proposed decoder are from $2.06\times $ to $2.93\times $ .

关键词： Decoding Viterbi algorithm Message systems Graphics processing units Throughput Memory management Quantization (signal) convolutional code graphics processing unit (GPU) parallel decoding software defined radio (SDR) Viterbi

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On error exponents for woven convolutional codes with one tailbiting component code

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IEEE TRANSACTIONS ON INFORMATION THEORY 2004年第8期50卷 1809-1811页

作者： Handlery, M Johannesson, R Zyablov, VV Lund Univ Dept Informat Technol SE-22100 Lund Sweden Russian Acad Sci Inst Problems Informat Transmiss Moscow 101447 Russia

An error exponent for woven convolutional codes (WCC) with one tailbiting component code is derived. This error exponent is compared with that of the original WCC. It is shown that for WCC with outer warp, a better error exponent is obtained if the inner code is terminated with the tailbiting method. Furthermore, it is shown that the decoding error probability decreases exponentially with the square of the memory of the constituent convolutional encoders, while the decoding complexity grows exponentially only with the memory.

关键词： convolutional code error exponent tailbiting code woven convolutional code (WCC)

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