共查询到20条相似文献,搜索用时 109 毫秒
1.
2.
3.
《中国无线电电子学文摘》2000,(1)
TN91 .00010937M CS一51系列单片机多机通信的实现/祁志勇,吕汉兴(华中理工大学)11仪表技术一1999,(3)一15一17介绍了M CS一51系列单片机多机通信的实现并对其实际应用中出现的新问题进行了剖析,提出了解决问题的方法,给出了程序示例。图2参2(木)TN911 00010941二元[n,2」线性码的广义汉明重量谱/罗守山,陈萍,杨义先(北京邮电大学)11电子学报一1999,27(7)一110一112文中给出了二元【n,2〕线性码的广义汉明重量谱的计数与分布.图1参2(金)TN91 00010938三网融合与通信体制革命/侯自强(中国科学院声学所)“微型机与应用.一1999,18(s)一4一… 相似文献
4.
5.
一个长度为n,维数为k的线性不等保护能力(LUEP)码可记为[n,k,s],其中s=(s_1,…,s_k)为分离矢量,s_1为第i个信息元m_i的分离重量,它的定义为 (1)式中G为[n,k,s]的生成矩阵,m为信息序列,w_i(·)为汉明重量。通常情况下,我们都约定s按非增规律 相似文献
6.
7.
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
8.
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
9.
10.
11.
The Hamming weight hierarchy of a linear [n,k;q] code c over GF(q)is the sequence(d1,d2,…,dk),where dr is the smallest support weight of an r-dimensional subcode of c.According to some new necessary conditions,the VI class Hamming weight hierarchies of q -ary linear codes of dimension 5 can be divided into six subclasses. By using the finite projective geometry method, VI-2 subclass and determine were researched almost all weight hierarchies of the VI-2 subclass of weight hierarchies of q -ary linear codes with dimension 5. 相似文献
12.
13.
Generalized Hamming weights of q-ary Reed-Muller codes 总被引:3,自引:0,他引:3
Heijnen P. Pellikaan R. 《IEEE transactions on information theory / Professional Technical Group on Information Theory》1998,44(1):181-196
The order bound on generalized Hamming weights is introduced in a general setting of codes on varieties which comprises both the one point geometric Goppa codes as well as the q-ary Reed-Muller codes. For the latter codes it is shown that this bound is sharp and that they satisfy the double chain condition 相似文献
14.
Pellikan R. Shen B.-Z. van Wee G.J.M. 《IEEE transactions on information theory / Professional Technical Group on Information Theory》1991,37(3):583-602
An infinite series of curves is constructed in order to show that all linear codes can be obtained from curves using Goppa's construction. If conditions are imposed on the degree of the divisor use, then criteria are derived for linear codes to be algebraic-geometric. In particular. the family of q-ary Hamming codes is investigated, and it is proven that only those with redundancy one or two and the binary (7,4,3) code are algebraic-geometric in this sense. For these codes. the authors explicitly give a curve, rational points, and a divisor. It is proven that this triple is in a certain sense unique in the case of the (7,4,3) code.<> 相似文献
15.
A characterization of MMD codes 总被引:2,自引:0,他引:2
Faldum A. Willems W. 《IEEE transactions on information theory / Professional Technical Group on Information Theory》1998,44(4):1555-1558
Let C be a linear [n,k,d]-code over GF(q) with k⩾2. If s=n-k+1-d denotes the defect of C, then by the Griesmer bound, d⩽(s+1)q. Now, for obvious reasons, we are interested in codes of given defect s for which the minimum distance is maximal, i.e., d=(s+1)q. We classify up to formal equivalence all such linear codes over GF(q). Remember that two codes over GF(q) are formally equivalent if they have the same weight distribution. It turns out that for k⩾3 such codes exist only in dimension 3 and 4 with the ternary extended Golay code, the ternary dual Golay code, and the binary even-weight code as exceptions. In dimension 4 they are related to ovoids in PG(3,q) except the binary extended Hamming code, and in dimension 3 to maximal arcs in PG(2,q) 相似文献
16.
Tolhuizen L.M.G.M. 《IEEE transactions on information theory / Professional Technical Group on Information Theory》2002,48(9):2573-2577
We consider the product code C/sub p/ of q-ary linear codes with minimum distances d/sub c/ and d/sub r/. The words in C/sub p/ of weight less than d/sub r/d/sub c/+max(d/sub r//spl lceil/(d/sub c//g)/spl rceil/,d/sub c//spl lceil/(d/sub r//q)/spl rceil/) are characterized, and their number is expressed in the number of low-weight words of the constituent codes. For binary product codes, we give an upper bound on the number of words in C/sub p/ of weightless than min(d/sub r/(d/sub c/+/spl lceil/(d/sub c//2)/spl rceil/+1)), d/sub c/(d/sub r/+/spl lceil/(d/sub r//2)/spl rceil/+1) that is met with equality if C/sub c/ and C/sub r/ are (extended) perfect codes. 相似文献
17.
Feng G.L. Tzeng K.K. Wei V.K. 《IEEE transactions on information theory / Professional Technical Group on Information Theory》1992,38(3):1125-1130
The generalized Hamming weights of a linear code are fundamental code parameters related to the minimal overlap structures of the subcodes. They were introduced by V.K. Wei (1991) and shown to characterize the performance of the linear code in certain cryptographical applications. Results are presented on the generalized Hamming weights of several classes of binary cyclic codes, including primitive double-error-correcting and triple-error-correcting BCH codes, certain reversible cyclic codes, and some extended binary Goppa codes. In particular, the second generalized Hamming weight of primitive double-error-correcting BCH codes is determined and upper and lower bounds are obtained for the generalized Hamming weights for the codes studied. These bounds are compared to results from other methods 相似文献
18.
Changshik Shim Habong Chung 《IEEE transactions on information theory / Professional Technical Group on Information Theory》1995,41(3):805-808
The generalized Hamming weight of a linear code is a new notion of higher dimensional Hamming weights. Let C be an [n,k] linear code and D be a subcode. The support of D is the cardinality of the set of not-always-zero bit positions of D. The rth generalized Hamming weight of C, denoted by dr(C), is defined as the minimum support of an r-dimensional subcode of C. It was shown by Wei (1991) that the generalized Hamming weight hierarchy of a linear code completely characterizes the performance of the code on the type II wire-tap channel defined by Ozarow and Wyner (1984). In the present paper the second generalized Hamming weight of the dual code of a double-error-correcting BCH code is derived and the authors prove that except for m=4, the second generalized Hamming weight of [2m-1, 2m]-dual BCH codes achieves the Griesmer bound 相似文献
19.
本文将线性码的广义Hamming重量的概念推广到非线性码上去,并导出了一种广义Elias界.对于线性等重码,本文给出了其完整的重量谱系. 相似文献
20.
首先给出了环R=Fp+vFp+v2Fp上线性码及其对偶码的结构及其Gray象的性质.定义了环R上线性码的各种重量计数器并讨论了它们之间的关系,特别的,确定了该环上线性码与其对偶码之间关于完全重量计数器的MacWilliams恒等式,利用该恒等式,进一步建立了该环上线性码与其对偶码之间的一种对称形式的MacWilliams恒等式.最后,利用该对称形式的MacWilliams恒等式得到了该环上的Hamming重量计数器和Lee重量计数器的MacWilliams恒等式,利用不同的方法推广了文献[7]中的结果. 相似文献