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1.
关于BCH码的广义Hamming重量上,下限 总被引:2,自引:0,他引:2
一个线性码的第r广义Hamming重量是它任意r维子码的最小支集大小。本文给出了一般(本原、狭义)BCH码的广义Hamming重量下限和一类BCH码的广义Hamming重量上限 相似文献
2.
《Communications, IEEE Transactions on》2009,57(5):1215-1220
In many communications systems, data can be divided into different importance levels. For these systems, unequal error protection (UEP) techniques are used to guarantee lower BER for the more important classes. In particular, if the precise characteristics of the channel are not known, UEP can be used to recover the more important classes even in poor receiving conditions. In this paper, we derive bounds on the performance of unequal error protecting turbo codes. These bounds serve as an important tool in predicting the performance of these codes. In order to derive the bounds, we introduce the notion of UEPuniform interleaver which is a random interleaver that does not change the order of classes in the turbo code frame. We also present a method to derive the weight enumerating function for UEP turbo codes. 相似文献
3.
Roth R.M. Seroussi G. 《IEEE transactions on information theory / Professional Technical Group on Information Theory》2007,53(8):2760-2768
New lower bounds are presented on the second moment of the distance distribution of binary codes, in terms of the first moment of the distribution. These bounds are used to obtain upper bounds on the size of codes whose maximum distance is close to their minimum distance. It is then demonstrated how such bounds can be applied to bound from below the smallest attainable ratio between the maximum distance and the minimum distance of codes. Finally, counterparts of the bounds are derived for the special case of constant-weight codes. 相似文献
4.
有仲裁人认证码的信息论下界 总被引:2,自引:0,他引:2
在Simmons给出的有仲裁人认证码中,主要研究了五种欺骗攻击。Johnsson对这些欺骗成功概率的信息论下界进行了研究。本文则给出了有仲裁人认证码中的敌方和收方的i(≥0)阶欺骗攻击成功概率的信息认下界,完善了关于欺骗攻击成功概率的下界的研究。 相似文献
5.
In this letter, we propose tight performance upper bounds for convolutional codes terminated with an input sequence of finite length. To obtain the upper bounds, a weight enumerator is defined to represent the relation between the Hamming distance of the coded output and the Hamming distance of the input bits of the code. The upper bounds on frame error rate (FER) and average bit error rate (BER) are obtained from the weight enumerator. A simple method is presented to compute the weight enumerator of a terminated convolutional code based on a modified trellis diagram. 相似文献
6.
《IEEE transactions on information theory / Professional Technical Group on Information Theory》2007,53(12):4537-4555
7.
Haas W. 《IEEE transactions on information theory / Professional Technical Group on Information Theory》2007,53(8):2880-2881
Let K(n, l) denote the minimal cardinality of a binary code of length n and covering radius one. Blass and Litsyn proved a lower bound K(n, l) for in the case n equiv 5 (mod6). We give a simplification of the proof, which yields a slightly better result. 相似文献
8.
设Qq(n,d)代表码长为n、任意两个不同码字间的Hamming距离为d的q元等距码所能达到的最大可能码字数(不考虑码的重量);Eq(n,d,w)代表码长为n、任意两个不同码字间Ham-ming距离为d、每个码字重量为w的q元等距等重码所能达到的最大可能码字数量.设q,n,d,w∈N,获得当q>2时,有①Eq(n,d,w)≤qn,②Qq(n,d)≤qn+1;当q=2时,则有③Eq(n,d,w)≤n,④Qq(n,d)≤n+1. 相似文献
9.
本文研究了二元等重码不可检错误概率(UEP)的界.首先,我们通过研究二元等重码的对偶距离分布及其性质,给出二元等重码UEP的一个新的下界,该下界改进了Fu-Kl ve-Wei的最新结果;然后,我们指出2003年Fu-Kl ve-Wei关于二元等重码UEP上界的某些结果有错误,我们随后给出更正后的结果,即二元等重码UEP的平均值和一个上界. 相似文献
10.
《IEEE transactions on information theory / Professional Technical Group on Information Theory》2009,55(4):1721-1729
11.
Code checkers that monitor the outputs of a system can detect both permanent and transient faults. We present two novel architectures of embedded self-testing checkers for low-cost and cyclic arithmetic codes, one based on code word generators and adders, the other based on code word accumulators. In these schemes, the code checker receives all possible code words but one, irrespective of the number of different code words that are produced by the circuit under check (CUC). So any code checker can be employed that is self-testing for all or a particular subset of code words, and the structure of the code checker need not be tailored to the set of code words produced by the CUC. The proposed code word generators and accumulators are built from simple standard hardware structures, counters and end-around-carry adders. They can also be utilized in an off-line BIST environment as pattern generators and test response compactors. 相似文献
12.
循环码的周期分布的新的计算公式 总被引:17,自引:1,他引:17
本文在[1]文的基础上进一步分析了循环码的周期分布的性质,给出了新的计算方法和公式,并且确定了一些熟知的循环码的周期分布。 相似文献
13.
《IEEE transactions on information theory / Professional Technical Group on Information Theory》2009,55(3):977-996
14.
Stinson D. Zaverucha G.M. 《IEEE transactions on information theory / Professional Technical Group on Information Theory》2008,54(6):2508-2514
We present some improved bounds on necessary conditions for separating hash families of type {w, w} and type {w, w - 1}. In particular, these bounds apply to secure frame- proof codes, which are equivalent to separating hash families of type {w, w}. We also consider existence results for separating hash families of type {w, w2} that can be obtained from the probabilistic method. The asymptotic behavior of these bounds is analyzed. 相似文献
15.
Sason I. Goldenberg I. 《IEEE transactions on information theory / Professional Technical Group on Information Theory》2007,53(7):2394-2428
The transmission of coded communication systems is widely modeled to take place over a set of parallel channels. This model is used for transmission over block-fading channels, rate-compatible puncturing of turbo-like codes, multicarrier signaling, multilevel coding, etc. New upper bounds on the maximum-likelihood (ML) decoding error probability are derived in the parallel-channel setting. We focus on the generalization of the Gallager-type bounds and discuss the connections between some versions of these bounds. The tightness of these bounds for parallel channels is exemplified for structured ensembles of turbo codes, repeat-accumulate (RA) codes, and some of their recent variations (e.g., punctured accumulate-repeat-accumulate codes). The bounds on the decoding error probability of an ML decoder are compared to computer simulations of iterative decoding. The new bounds show a remarkable improvement over the union bound and some other previously reported bounds for independent parallel channels. This improvement is exemplified for relatively short block lengths, and it is pronounced when the block length is increased. In the asymptotic case, where we let the block length tend to infinity, inner bounds on the attainable channel regions of modern coding techniques under ML decoding are obtained, based solely on the asymptotic growth rates of the average distance spectra of these code ensembles. 相似文献
16.
一类循环码的神经网络软判决译码算法 总被引:2,自引:0,他引:2
本文分析了一类循环码的结构特性,提出了这类循环码的神经网络软判决译码算法。新算法的复杂度比现有一般的神经网络译码算法要低得多,而其译码性能接近大似然译码。 相似文献
17.
With digital implementations of the Viterbi decoding algorithm for convolutional codes, soft quantization is preferred over hard quantization because it generally yields superior performance. Since the decoder needs to know the signal energy and channel noise variance with soft quantization, inaccurate information can result in a mismatch between the channel and decoder. Bounds which are tight for high signal-to-noise ratios are obtained on the bit error probability using the generating function approach. Automatic gain control level inaccuracies, imperfect carrier phase, symbol timing synchronization error, and path metric digitization are discussed in the context of a mismatch between the channel and decoder. 相似文献
18.
该文利用Krawtchouk多项式函数给出了纯的加性量子纠错码的两个不同的上界,并进一步证明了量子Singleton界和渐近量子Hamming界只是这两个上界的特例。 相似文献
19.
We study skew cyclic codes over a non-chain ring, which generalizes our previous results in IEICE Trans. on Fundamentals of Electronic Communications and Computer Sciences, 2015. We describe generator polynomi-als of skew cyclic codes over this ring and investigate the structural properties of skew cyclic codes over the ring by a decomposition theorem. The generator polynomial of the dual code of a skew cyclic code are obtained. Moreover, the idempotent generators of skew cyclic codes are consid-ered. Some examples are also presented to illustrate the discussed results. 相似文献
20.
《IEEE transactions on information theory / Professional Technical Group on Information Theory》2008,54(3):1024-1035