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SIMULATED-ANNEALING-BASED SELECTION OF BINARY CODES
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作者 李炳成 《Journal of Electronics(China)》 1991年第4期317-323,共7页
Binary code signals have been widely used in various radars due to their simpleimplementation,but the selection of the binary codes with high comporession ratio and lowsidelobes is not solved well,because of the diffi... Binary code signals have been widely used in various radars due to their simpleimplementation,but the selection of the binary codes with high comporession ratio and lowsidelobes is not solved well,because of the difficult processing in mathmatics and expensivecalculation cost.In this paper,neural computing is introduced into the field of the selection ofbinary codes and a new method based’on simulated annealing(SA)is proposed.The experimentsshow that the proposed method is able to select the optimal binary codes with much less timecost than the known methods,furhtermore the optimization selection of the binary codes versusthe calculation cost tradeoff is easier. 展开更多
关键词 binary codes Selecting codes SIDELOBES SIMULATED annealing(SA)
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Fast approximate matching of binary codes with distinctive bits 被引量:3
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作者 Chenggang Clarence YAN Hongtao XIE +3 位作者 Bing ZHANG Yanping MA Qiong DAI Yizhi LIU 《Frontiers of Computer Science》 SCIE EI CSCD 2015年第5期741-750,共10页
Although the distance between binary codes can be computed fast in Hamming space, linear search is not practical for large scale datasets. Therefore attention has been paid to the efficiency of performing approximate ... Although the distance between binary codes can be computed fast in Hamming space, linear search is not practical for large scale datasets. Therefore attention has been paid to the efficiency of performing approximate nearest neighbor search, in which hierarchical clustering trees (HCT) are widely used. However, HCT select cluster centers randomly and build indexes with the entire binary code, this degrades search performance. In this paper, we first propose a new clustering algorithm, which chooses cluster centers on the basis of relative distances and uses a more homogeneous partition of the dataset than HCT has to build the hierarchical clustering trees. Then, we present an algorithm to compress binary codes by extracting distinctive bits according to the standard deviation of each bit. Consequently, a new index is proposed using compressed binary codes based on hierarchical decomposition of binary spaces. Experiments conducted on reference datasets and a dataset of one billion binary codes demonstrate the effectiveness and efficiency of our method. 展开更多
关键词 binary codes approximate nearest neighbor search hierarchical clustering index
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Research of Methods for Lost Data Reconstruction in Erasure Codes over Binary Fields 被引量:2
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作者 Dan Tang 《Journal of Electronic Science and Technology》 CAS CSCD 2016年第1期43-48,共6页
In the process of encoding and decoding,erasure codes over binary fields,which just need AND operations and XOR operations and therefore have a high computational efficiency,are widely used in various fields of inform... In the process of encoding and decoding,erasure codes over binary fields,which just need AND operations and XOR operations and therefore have a high computational efficiency,are widely used in various fields of information technology.A matrix decoding method is proposed in this paper.The method is a universal data reconstruction scheme for erasure codes over binary fields.Besides a pre-judgment that whether errors can be recovered,the method can rebuild sectors of loss data on a fault-tolerant storage system constructed by erasure codes for disk errors.Data reconstruction process of the new method has simple and clear steps,so it is beneficial for implementation of computer codes.And more,it can be applied to other non-binary fields easily,so it is expected that the method has an extensive application in the future. 展开更多
关键词 binary fields data reconstruction decoding erasure codes
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Optimal binary codes and binary construction of quantum codes
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作者 Weiliang WANG Yangyu FAN Ruihu LI 《Frontiers of Computer Science》 SCIE EI CSCD 2014年第6期1024-1030,1031,共8页
This paper discusses optimal binary codes and pure binary quantum codes created using Steane construction. First, a local search algorithm for a special subclass of quasi-cyclic codes is proposed, then five binary qua... This paper discusses optimal binary codes and pure binary quantum codes created using Steane construction. First, a local search algorithm for a special subclass of quasi-cyclic codes is proposed, then five binary quasi-cyclic codes are built. Second, three classical construction methods are generalized for new codes from old such that they are suitable for constructing binary self-orthogonal codes, and 62 binary codes and six subcode chains of obtained self-orthogonal codes are designed. Third, six pure binary quantum codes are constructed from the code pairs obtained through Steane construction. There are 66 good binary codes that include 12 optimal linear codes, 45 known optimal linear codes, and nine known optimal self-orthogonal codes. The six pure binary quantum codes all achieve the performance of their additive counterparts constructed by quaternary construction and thus are known optimal codes. 展开更多
关键词 binary linear code binary self-orthogonal code quasi-cyclic code Steane construction quantum code.
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THE NEW METHOD OF GENERATION OF BINARY TREES FROM ZER0(0) AND ONE(1) CODES
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作者 蔡恒 《Journal of China Textile University(English Edition)》 EI CAS 1995年第2期94-99,共6页
A binary tree can be represented by a code reflecting the traversal of the corresponding regular binary tree in given monotonic order. A different coding scheme based on the branches of a regular binary tree with n-no... A binary tree can be represented by a code reflecting the traversal of the corresponding regular binary tree in given monotonic order. A different coding scheme based on the branches of a regular binary tree with n-nodes is proposed. It differs from the coding scheme generally used and makes no distinction between internal nodes and terminal nodes. A code of a regular binary tree with nnodes is formed by labeling the left branches by O’s and the right branches by l’s and then traversing these branches in pre-order. Root is always assumed to be on a left branch. 展开更多
关键词 code TRAVERSAL MONOTONIC order binary TREE RECURSION backtrack approach algorithm design.
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Binary Cyclic Codes and Minimal Codewords
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作者 Selda Calkavur 《Computer Technology and Application》 2013年第9期486-489,共4页
Cyclic codes form an important class of codes. They have very interesting algebraic structure. Furthermore, they are equivalent to many important codes, such as binary Hamming codes, Golay codes and BCH codes. Minimal... Cyclic codes form an important class of codes. They have very interesting algebraic structure. Furthermore, they are equivalent to many important codes, such as binary Hamming codes, Golay codes and BCH codes. Minimal codewords in linear codes are widely used in constructing decoding algorithms and studying linear secret sharing scheme. In this paper, we show that in the binary cyclic code all of the codewords are minimal, except 0 and 1. Then, we obtain a result about the number of minimal codewords in the binary cyclic codes. 展开更多
关键词 Linear code cyclic code binary cyclic code generator polynomial minimal codeword secret sharing.
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A Novel Decoding Method for Non-Binary TCM Codes
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作者 Riyadh A. Al-Hilali Abdulkareem S. Abdallah Raad H. Thaher 《Communications and Network》 2014年第1期22-28,共7页
A new non-binary decoding method, which is called Yaletharatalhussein decoding algorithm, is designed and implemented for decoding non-binary convolutional codes which is based on the trellis diagram representing the ... A new non-binary decoding method, which is called Yaletharatalhussein decoding algorithm, is designed and implemented for decoding non-binary convolutional codes which is based on the trellis diagram representing the convolutional encoder. Yaletharatalhussein decoding algorithm outperforms the Viterbi algorithm and other algorithms in its simplicity, very small computational complexity, decoding reliability for high states TCM codes that suitable for Fourth-Generation (4G), decreasing errors with increasing word length, and easy to implement with real-time applications. The proposed Yaletharatalhussein decoding algorithm deals with non-binary error control coding of the convolutional and TCM codes. Convolutional codes differ from block codes in that a block code takes a fixed message length and encodes it, whereas a convolutional code can encode a continuous stream of data, and a hard-decision decoding can easily be realized using the Yaletharatalhussein algorithm. The idea of non-binary codes has been extended for symbols defined over rings of integers, which outperform binary codes with only a small increase in decoding complexity. The simulation results show that the performance of the nonbinary TCM-based Yaletharatalhussein algorithm outperforms the binary and non-binary decoding methods. 展开更多
关键词 Convolutional codes Coded MODULATION (CM) Trellis Code MODULATION (TCM) Non-binary Error Correcting codes Groups Rings of Integers
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基于Barker码脉冲压缩技术的钢板多阵元Lamb波电磁超声换能器设计与优化
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作者 石文泽 李淇鑫 +2 位作者 卢超 胡博 刘远 《电工技术学报》 EI CSCD 北大核心 2024年第8期2371-2387,共17页
为了解决传统Barker码脉冲压缩技术受脉冲功率放大器额定参数(占空比,最大脉冲宽度等)限制而导致的脉冲压缩效果下降、检测速度降低等问题,提出一种基于Barker码脉冲压缩技术的多阵元Lamb波电磁超声换能器(EMAT)。建立了基于tone-burst... 为了解决传统Barker码脉冲压缩技术受脉冲功率放大器额定参数(占空比,最大脉冲宽度等)限制而导致的脉冲压缩效果下降、检测速度降低等问题,提出一种基于Barker码脉冲压缩技术的多阵元Lamb波电磁超声换能器(EMAT)。建立了基于tone-burst信号激励-Barker码脉冲压缩技术的多阵元Lamb波EMAT检测过程的有限元模型,分析了永磁体的配置形式、阵元序列长度、激励信号周期数、曲折线圈匝数等因素对脉冲压缩后的主旁瓣比和主瓣宽度的影响,并进行了实验验证。结果表明:曲折线圈匝数为4和Barker码序列长度为13位的多阵元EMAT在配置3对外置永磁体后,其信噪比(SNR)可提高9.8 dB。综合考虑检测回波的空间分辨率和SNR,多阵元Lamb波EMAT最佳参数为:曲折线圈匝数为10、激励信号周期数为11、Barker序列为13位,并配置3对外置永磁体。 展开更多
关键词 电磁超声换能器 barker码脉冲压缩 多阵元Lamb波EMAT 信噪比 空间分辨率
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Construction of Regular Rate-Compatible LDPC Convolutional Codes 被引量:1
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作者 Liwei Mu Chulong Liang +1 位作者 Zhiyong Liu Daru Pan 《China Communications》 SCIE CSCD 2016年第8期97-102,共6页
In this paper, we propose a new method to derive a family of regular rate-compatible low-density parity-check(RC-LDPC) convolutional codes from RC-LDPC block codes. In the RC-LDPC convolutional family, each extended... In this paper, we propose a new method to derive a family of regular rate-compatible low-density parity-check(RC-LDPC) convolutional codes from RC-LDPC block codes. In the RC-LDPC convolutional family, each extended sub-matrix of each extended code is obtained by choosing specified elements from two fixed matrices HE1K and HE1K, which are derived by modifying the extended matrices HE1 and HE2 of a systematic RC-LDPC block code. The proposed method which is based on graph extension simplifies the design, and prevent the defects caused by the puncturing method. It can be used to generate both regular and irregular RC-LDPC convolutional codes. All resulted codes in the family are systematic which simplify the encoder structure and have maximum encoding memories which ensure the property. Simulation results show the family collectively offer a steady improvement in performance with code compatibility over binary-input additive white Gaussian noise channel(BI-AWGNC). 展开更多
关键词 binary-input additive white Gaussian noise channel(BI-AWGNC) extended matrices rate-compatible low-density parity-check(RC-LDPC) convolutional codes
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[[2n ,n]] ADDITIVE QUANTUM ERROR CORRECTING CODES
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作者 Du Yongjun Ma Yuefei 《Journal of Electronics(China)》 2008年第4期519-522,共4页
The self-orthogonal condition is analyzed with respect to symplectic inner product for the binary code that generated by [B1 I B2 B3],where Bi are the binary n ×n matrices,I is an identity matrix.By the use of th... The self-orthogonal condition is analyzed with respect to symplectic inner product for the binary code that generated by [B1 I B2 B3],where Bi are the binary n ×n matrices,I is an identity matrix.By the use of the binary codes that generated by [B1 I B2 B2B1^T],asymptotic good[[2n ,n ]]additive quantum codes are obtained. 展开更多
关键词 Additive quantum codes binary codes Symplectic inner product Asymptotic good codes
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A New Description of the Additive Quantum Codes
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作者 唐黎明 刘焕平 吕学琴 《Northeastern Mathematical Journal》 CSCD 2006年第3期285-290,共6页
A new description of the additive quantum codes is presented and a new way to construct good quantum codes [[n, k, d]] is given by using classical binary codes with specific properties in F2^3n. We show several conseq... A new description of the additive quantum codes is presented and a new way to construct good quantum codes [[n, k, d]] is given by using classical binary codes with specific properties in F2^3n. We show several consequences and examples of good quantum codes by using our new description of the additive quantum codes. 展开更多
关键词 quantum code binary linear code dual code
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Construction of New Codes from Given Ones in an Additive Channel
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作者 Garib Movsisyan 《Journal of Information Security》 2016年第3期165-171,共7页
In the present work, a construction making possible creation of an additive channel  of cardinality s and rank r for arbitrary integers s, r, n (r≤min (n,s-1)), as well as creation of a code  correcting err... In the present work, a construction making possible creation of an additive channel  of cardinality s and rank r for arbitrary integers s, r, n (r≤min (n,s-1)), as well as creation of a code  correcting errors of the channel A is presented. 展开更多
关键词 Additive Channel Golay Code Classical Coding Theory T-Order Neighborhood Correcting Code binary Alphabet CARDINALITY
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11位Barker码性能研究 被引量:4
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作者 赵晓群 李炳新 +1 位作者 贾世楼 王仲文 《系统工程与电子技术》 EI CSCD 1997年第6期56-58,61,共4页
本文分析了11位长Barker码在加权相关意义下的性能,指出在二值加权相关意义下旁瓣电平下降了1.58dB,达到-22.41dB;在三值加权相关意义下旁瓣电平下降了3.52dB,达到-24.35dB;为工程应用提供了一种新的脉冲压缩方法。
关键词 相关技术 脉冲压缩 barker 雷达
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二值映射相关Barker码研究 被引量:3
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作者 赵晓群 贾世楼 +1 位作者 王仲文 李炳新 《通信学报》 EI CSCD 北大核心 1998年第9期87-90,共4页
给出了二相序列非周期二值映射相关函数的定义,在该定义的基础上定义了二值映射相关Barker码(简称二值加权Barker码),并指出经典的二相序列的非周期相关函数和Barker码是本文新定义的相关函数和Barker码的... 给出了二相序列非周期二值映射相关函数的定义,在该定义的基础上定义了二值映射相关Barker码(简称二值加权Barker码),并指出经典的二相序列的非周期相关函数和Barker码是本文新定义的相关函数和Barker码的特例。新定义的Barker码比原意义的Barker码多5个码字,而且对原意义下的Barker码经加权处理后,可提高主副峰比(长为7的Barker码提高2.5dB,长为11的Barker码提高1.57dB),计算机搜索结果证明长度大于13、小于31的二值加权Barker码是不存在的。 展开更多
关键词 二相序列 自相关函数 barker 映射相关
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三值映射相关 Barker 码研究 被引量:3
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作者 赵晓群 李炳新 +1 位作者 王仲文 贾世楼 《东北重型机械学院学报》 CAS 1997年第1期50-54,共5页
给出了二相序列非周期三值映射相关函数的定义,在该定义的基础上研究了三值映射相关Barker码(简称三值加权Barker码),指出经典的二相序列的非周期相关函数和Barker码是本文新定义的相关函数和Barker码的特... 给出了二相序列非周期三值映射相关函数的定义,在该定义的基础上研究了三值映射相关Barker码(简称三值加权Barker码),指出经典的二相序列的非周期相关函数和Barker码是本文新定义的相关函数和Barker码的特例.新定义的Barker码比原意义的Barker码多21个码字,并找出长为6,8,10的Barker码共计12个,而且原意义下的Barker码经三值加权处理后,可提高主副峰比(码长为7的Barker码提高3.5dB,码长为11的Barker码提高3.52dB),计算机搜索结果证明长度大于13、小于26的三值加权Barker码是不存在的. 展开更多
关键词 自相关函数 barker 三值映射 通信理论
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搜索三加权Barker码的穷举算法 被引量:3
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作者 李炳新 王志荣 赵晓群 《燕山大学学报》 CAS 1999年第4期350-351,共2页
在三值映射自相关函数定义的基础上,提出了搜索三加权Barker码的穷举算法,给出了码长小于26的结果。
关键词 三值映射 自相关函数 三加权 barker 穷举算法
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搜寻二加权Barker码的穷举算法 被引量:3
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作者 李炳新 赵晓群 蔡艳 《东北重型机械学院学报》 CAS 1996年第3期234-237,共4页
在二值映射自相关函数定义的基础上.提出了搜寻二加权Barker码的穷举算法.给出了码长小于30的结果.
关键词 二值映射 自相关函数 加权barker
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一种最优码宽的Barker码超声液位测量技术研究 被引量:1
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作者 李鹏 王银娟 +1 位作者 冯彬彬 尹杰 《科学技术与工程》 北大核心 2013年第32期9486-9493,共8页
超声编码发射技术是一种有效的提高超声测量精度的方法。通过实验验证,提出了在超声测量中,采用最优码宽的13位Barker数字编码激励,并结合匹配滤波解码压缩的方法替代传统的单脉冲激励的方法,通过对回波信号能量压缩以及对测量系统的优... 超声编码发射技术是一种有效的提高超声测量精度的方法。通过实验验证,提出了在超声测量中,采用最优码宽的13位Barker数字编码激励,并结合匹配滤波解码压缩的方法替代传统的单脉冲激励的方法,通过对回波信号能量压缩以及对测量系统的优化。并且在实验的基础上加入渡越时间的修正量,形成了新的超声液位测量技术;并通过实验进行验证。仿真和实验结果表明,液面静止状态下,巴克码激励方式渡越时间修正前与修正后测量绝对误差比单脉冲激励方式,分别最少减小0.631 mm和1.617 mm。与传统的单脉冲测量在分辨率、信噪比等方面比较,编码激励技术能有效地改善超声测量的精度,具有较强的实际应用价值和市场前景。 展开更多
关键词 超声波 巴克码 修正量 液位测量
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基于Barker码可靠网络流水印研究与实现 被引量:1
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作者 孙海霞 何磊 胡永 《实验技术与管理》 CAS 北大核心 2015年第4期166-170,共5页
针对当前网络流水印技术存在的水印容量小、时间复杂度高问题,提出了一种基于Barker码的可靠网络流水印方法。该方法选择具有同步特性的Barker码作为PN码,通过扩频操作,将原始水印信息变为扩频信息序列,保证该序列具有自同步特性。通过... 针对当前网络流水印技术存在的水印容量小、时间复杂度高问题,提出了一种基于Barker码的可靠网络流水印方法。该方法选择具有同步特性的Barker码作为PN码,通过扩频操作,将原始水印信息变为扩频信息序列,保证该序列具有自同步特性。通过主动调整网络流内数据包时间间隔IPD的大小来表示该信息序列,以完成原始水印信息在网络流内的嵌入过程。接收方在获取网络流的IPD值后,通过解扩操作即可恢复出该水印信息。实验结果表明,与其他方法相比,该法不仅能够明显提高网络流的水印容量,还能有效降低水印嵌入和提取过程的时间。 展开更多
关键词 barker 网络流水印 匿名通信 跳板节点 直接序列扩频
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Barker码的一些结论和二元码的优选问题 被引量:3
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作者 杨光正 《电子科学学刊》 CSCD 1995年第1期35-41,共7页
本文最终证明了不存在n>13位的Barker码,并探索了二相码的解析优选法。文中定义了一个Y_n矩阵,并由Y_n导出了二相码的重量w,Hamming距离d,游程数ι和码长n之间的关系式,所得关系不仅揭示出二相码各参数之间的内在联系,而且可用它来解... 本文最终证明了不存在n>13位的Barker码,并探索了二相码的解析优选法。文中定义了一个Y_n矩阵,并由Y_n导出了二相码的重量w,Hamming距离d,游程数ι和码长n之间的关系式,所得关系不仅揭示出二相码各参数之间的内在联系,而且可用它来解决Barker码的存在性问题,从而将二相码的优选问题建立在解析的基础上。文中还举出了应用实例。 展开更多
关键词 barker 二相码 选码方法
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