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Performance improvement of magneto-acousto-electrical tomography for biological tissues with sinusoid-Barker coded excitation 被引量:7
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作者 Zheng-Feng Yu Yan Zhou +4 位作者 Yu-Zhi Li Qing-Yu Ma Ge-Pu Guol Juan Tu Dong Zhang 《Chinese Physics B》 SCIE EI CAS CSCD 2018年第9期346-353,共8页
By combining magnetics, acoustics and electrics, the magneto-acoustic-electrical tomography(MAET) proves to possess the capability of differentiating electrical impedance variation and thus improving the spatial res... By combining magnetics, acoustics and electrics, the magneto-acoustic-electrical tomography(MAET) proves to possess the capability of differentiating electrical impedance variation and thus improving the spatial resolution. However,the signal-to-noise ratio(SNR) of the collected MAET signal is still unsatisfactory for biological tissues with low-level electrical conductivity. In this study, the formula of MAET measurement with sinusoid-Barker coded excitation is derived and simplified for a planar piston transducer. Numerical simulations are conducted for a four-layered gel phantom with the 13-bit sinusoid-Barker coded excitation, and the performances of wave packet recovery with side-lobe suppression are improved by using the mismatched compression filter, which is also demonstrated by experimentally measuring a three-layered gel phantom. It is demonstrated that comparing with the single-cycle sinusoidal excitation, the amplitude of the driving signal can be reduced greatly with an SNR enhancement of 10 dB using the 13-bit sinusoid-Barker coded excitation. The amplitude and polarity of the wave packet filtered from the collected MAET signal can be used to achieve the conductivity derivative at the tissue boundary. In this study, we apply the sinusoid-Barker coded modulation method and the mismatched suppression scheme to MAET measurement to ensure the safety for biological tissues with improved SNR and spatial resolution, and suggest the potential applications in biomedical imaging. 展开更多
关键词 magneto-acousto-electrical tomography sinusoid-barker coded excitation mismatched compression filter side lobe suppression
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Buffer Overflow Detection on Binary Code 被引量:2
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作者 郑燕飞 李晖 陈克非 《Journal of Shanghai Jiaotong university(Science)》 EI 2006年第2期224-229,共6页
Most solutions for detecting buffer overflow are based on source code. But the requirement tor source code is not always practical especially for business software. A new approach was presented to detect statically th... Most solutions for detecting buffer overflow are based on source code. But the requirement tor source code is not always practical especially for business software. A new approach was presented to detect statically the potential buffer overflow vulnerabilities in the binary code of software. The binary code was translated into assembly code without the lose of the information of string operation functions. The feature code abstract graph was constructed to generate more accurate constraint statements, and analyze the assembly code using the method of integer range constraint. After getting the elementary report on suspicious code where buffer overflows possibly happen, the control flow sensitive analysis using program dependence graph was done to decrease the rate of false positive. A prototype was implemented which demonstrates the feasibility and efficiency of the new approach. 展开更多
关键词 binary code buffer overflow integer range constraint feature abstract graph
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Multi-Wavelength vs. Binary Code Pattern Unwrapping in Fringe Projection Method 被引量:1
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作者 R. Talebi J. Johnson +1 位作者 A. Abdel-Dayem M. Saadatseresht 《通讯和计算机(中英文版)》 2014年第3期291-304,共14页
关键词 二进制代码 多波长 条纹 投射法 相位展开 码型 固相萃取 不连续性
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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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Unleashing the power of pseudo-code for binary code similarity analysis
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作者 Weiwei Zhang Zhengzi Xu +1 位作者 Yang Xiao Yinxing Xue 《Cybersecurity》 EI CSCD 2023年第2期44-61,共18页
Code similarity analysis has become more popular due to its significant applicantions,including vulnerability detection,malware detection,and patch analysis.Since the source code of the software is difficult to obtain... Code similarity analysis has become more popular due to its significant applicantions,including vulnerability detection,malware detection,and patch analysis.Since the source code of the software is difficult to obtain under most circumstances,binary-level code similarity analysis(BCSA)has been paid much attention to.In recent years,many BCSA studies incorporating Al techniques focus on deriving semantic information from binary functions with code representations such as assembly code,intermediate representations,and control flow graphs to measure the similarity.However,due to the impacts of different compilers,architectures,and obfuscations,binaries compiled from the same source code may vary considerably,which becomes the major obstacle for these works to obtain robust features.In this paper,we propose a solution,named UPPC(Unleashing the Power of Pseudo-code),which leverages the pseudo-code of binary function as input,to address the binary code similarity analysis challenge,since pseudocode has higher abstraction and is platform-independent compared to binary instructions.UPPC selectively inlines the functions to capture the full function semantics across different compiler optimization levels and uses a deep pyramidal convolutional neural network to obtain the semantic embedding of the function.We evaluated UPPC on a data set containing vulnerabilities and a data set including different architectures(X86,ARM),different optimization options(O0-O3),different compilers(GCC,Clang),and four obfuscation strategies.The experimental results show that the accuracy of UPPC in function search is 33.2%higher than that of existing methods. 展开更多
关键词 binary code similarity Machine learning Software security PSEUDO-code
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Detection of long bones based on Barker code excited ultrasonic guided waves 被引量:5
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作者 ZHANG Huilin SONG Xiaojun TA De'an 《Chinese Journal of Acoustics》 2014年第2期136-146,共11页
Single pulse excited ultrasonic guided wave surfers high attenuation during the propagation in long bones.This results in small amplitude and low signal-to-noise ratio(SNR)of measured signals.Thus,the Barker code ex... Single pulse excited ultrasonic guided wave surfers high attenuation during the propagation in long bones.This results in small amplitude and low signal-to-noise ratio(SNR)of measured signals.Thus,the Barker code excitation is introduced into long bone detection to improve the quality of received signals,due to its efficiency in increasing amplitude and SNR.Both simulation and in vitro experiment were performed,and the results were decoded by the weighted match filter(WMF) and the finite impulse response- least squares inverse filter(FIRLSIF),respectively.The comparison between the results of Barker code excitation and sine pulse excitation was presented.For 13-bit Barker code excitation,WMF produced 13 times larger amplitude than sine pulse excitation,while FIR-LSIF achieved higher peak-sidelobe-level(PSL) of -63.59 dB and better performance in noise suppression.The results show that the Barker code excited guided waves have the potential to be applied to the long bone detection. 展开更多
关键词 code Detection of long bones based on barker code excited ultrasonic guided waves FIR
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Bulk acoustic wave Barker code sequence and the application in ultrasonic NDT 被引量:2
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作者 BAI Yuhai and PEI Liwei (Institute of Acoustics, Academia Sinita. Beijing 100080 ) 《Chinese Journal of Acoustics》 1994年第3期219-223,共5页
A simple and convcnient method to gain bulk acoustic wave Barker code sequence is presented and the results of the correlation are givcn. The transducer response to a unit electric pulse is used as a unit code constit... A simple and convcnient method to gain bulk acoustic wave Barker code sequence is presented and the results of the correlation are givcn. The transducer response to a unit electric pulse is used as a unit code constituting the Barker code sequence of acoustic signal. The phase precision of the code sequence as well as the fairly ideal response function are guaranteed by the high accuraey of a DATA-2020 Arbitrary Waveform Synthesizer and a DATA-6000 Universal Wavcform Analyzer. Some deviations between the experiments and thcory are caused by the transient response and timc delay characteristics of the ultrasonic tansducer. 展开更多
关键词 barker code CORRELATION Ultrasonic NDT
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A Personalized Digital Code from Unique Genome Fingerprinting Pattern for Use in Identification and Application on Blockchain
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作者 Isaac Kise Lee 《Computational Molecular Bioscience》 CAS 2023年第1期1-20,共20页
With over 10 million points of genetic variation from person to person, every individual’s genome is unique and provides a highly reliable form of identification. This is because the genetic code is specific to each ... With over 10 million points of genetic variation from person to person, every individual’s genome is unique and provides a highly reliable form of identification. This is because the genetic code is specific to each individual and does not change over time. Genetic information has been used to identify individuals in a variety of contexts, such as criminal investigations, paternity tests, and medical research. In this study, each individual’s genetic makeup has been formatted to create a secure, unique code that incorporates various elements, such as species, gender, and the genetic identification code itself. The combinations of markers required for this code have been derived from common single nucleotide polymorphisms (SNPs), points of variation found in the human genome. The final output is in the form of a 24 numerical code with each number having three possible combinations. The custom code can then be utilized to create various modes of identification on the decentralized blockchain network as well as personalized services and products that offer users a novel way to uniquely identify themselves in ways that were not possible before. 展开更多
关键词 Genomic Fingerprint Digital code SNP’s Auxiliary code Marker Selection Blockchain WEB3.0 Decentralized Identification (DID)
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Statistical Recognition Method of Binary BCH Code 被引量:6
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作者 Jiafeng Wang Yang Yue Jun Yao 《Communications and Network》 2011年第1期17-22,共6页
In this paper, a statistical recognition method of the binary BCH code is proposed. The method is applied to both primitive and non-primitive binary BCH code. The block length is first recognized based on the cyclic f... In this paper, a statistical recognition method of the binary BCH code is proposed. The method is applied to both primitive and non-primitive binary BCH code. The block length is first recognized based on the cyclic feature under the condition of the frame length known. And then candidate polynomials are achieved which meet the restrictions. Among the candidate polynomials, the most optimal polynomial is selected based on the minimum rule of the weights sum of the syndromes. Finally, the best polynomial was factorized to get the generator polynomial recognized. Simulation results show that the method has strong capability of anti-random bit error. Besides, the algorithm proposed is very simple, so it is very practical for hardware im-plementation. 展开更多
关键词 binary BCH code BLIND Recognition code Length GENERATOR POLYNOMIAL
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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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Novel non-coherent integration method using binary phase-coded radar signal 被引量:2
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作者 田黎育 何苗 +1 位作者 刘斌 傅雄军 《Journal of Beijing Institute of Technology》 EI CAS 2013年第1期60-66,共7页
The m series with 511 bits is taken as an example being applied in non-coherent integra- tion algorithm. A method to choose the bi-phase code is presented, which is 15 kinds of codes are picked out of 511 kinds of m s... The m series with 511 bits is taken as an example being applied in non-coherent integra- tion algorithm. A method to choose the bi-phase code is presented, which is 15 kinds of codes are picked out of 511 kinds of m series to do non-coherent integration. It is indicated that the power in- creasing times of larger target sidelobe is less than the power increasing times of smaller target main- lobe because of the larger target' s pseudo-randomness. Smaller target is integrated from larger tar- get sidelobe, which strengthens the detection capability of radar for smaller targets. According to the sidelobes distributing characteristic, a method is presented in this paper to remove the estimated sidelobes mean value for signal detection after non-coherent integration. Simulation results present that the SNR of small target can be improved approximately 6. 5 dB by the proposed method. 展开更多
关键词 binary phase-coded signal non-coherent integration code agility peak sidelobe level(PSL) mainlobe-peak sidelobe ratio
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Implementation of a kind of FPGA-based binary phase coded radar signal processor architecture 被引量:1
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作者 田黎育 孙密 万阳良 《Journal of Beijing Institute of Technology》 EI CAS 2012年第4期526-531,共6页
A flexible field programmable gate array based radar signal processor is presented. The radar signal processor mainly consists of five functional modules: radar system timer, binary phase coded pulse compression(PC... A flexible field programmable gate array based radar signal processor is presented. The radar signal processor mainly consists of five functional modules: radar system timer, binary phase coded pulse compression(PC), moving target detection (MTD), constant false alarm rate (CFAR) and target dots processing. Preliminary target dots information is obtained in PC, MTD, and CFAR modules and Nios I! CPU is used for target dots combination and false sidelobe target removing. Sys- tem on programmable chip (SOPC) technique is adopted in the system in which SDRAM is used to cache data. Finally, a FPGA-based binary phase coded radar signal processor is realized and simula- tion result is given. 展开更多
关键词 field programmable gate array(FPGA) radar signal processor system on programma-ble chip (SOPC) binary phase coded
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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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DECODING ALGORITHM BASED QN REVISED SYNDROME FOR THE BINARY (23,12,7) GOLAY CODE
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作者 马建峰 王育民 《Journal of Electronics(China)》 1995年第1期33-37,共5页
A decoding algorithm based on revised syndromes to decode the binary (23,12,7) Golay code is presented. The algorithm strongly depends on the algebraic properties of the code. For the algorithm, the worst complexity i... A decoding algorithm based on revised syndromes to decode the binary (23,12,7) Golay code is presented. The algorithm strongly depends on the algebraic properties of the code. For the algorithm, the worst complexity is about 683 mod2 additions, which is less than that of the algorithms available for the code, the average complexity is approximately 319 mod2 additions, which is slightly more than that of Blaum’s algorithm for the code. 展开更多
关键词 binary GOLAY code Revised SYNDROME DECODING
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Palmprint Recognition Based on Statistical Local Binary Orientation Code
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作者 Mei-Ru Mu Qiu-Qi Ruan 《Journal of Electronic Science and Technology》 CAS 2010年第3期230-236,共7页
A novel coding based method named as local binary orientation code (LBOCode) for palmprint recognition is proposed. The palmprint image is firstly convolved with a bank of Gabor filters, and then the orientation inf... A novel coding based method named as local binary orientation code (LBOCode) for palmprint recognition is proposed. The palmprint image is firstly convolved with a bank of Gabor filters, and then the orientation information is attained with a winner-take-all rule. Subsequently, the resulting orientation mapping array is operated by uniform local binary pattern. Accordingly, LBOCode image is achieved which contains palmprint orientation information in pixel level. Further we divide the LBOCode image into several equal-size and nonoverlapping regions, and extract the statistical code histogram from each region independently, which builds a global description of palmprint in regional level. In matching stage, the matching score between two palmprints is achieved by calculating the two spatial enhanced histograms' dissimilarity, which brings the benefit of computational simplicity. Experimental results demonstrate that the proposed method achieves more promising recognition performance compared with that of several state-of-the-art methods. 展开更多
关键词 Gabor filter local binary pattern orientation code palmprint recognition.
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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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Bandwidth optimization of a Planar Inverted-F Antenna using binary and real coded genetic algorithms
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作者 AMEERUDDEN Mohammad Riyad RUGHOOPUTH Harry C S 《重庆邮电大学学报(自然科学版)》 北大核心 2009年第2期276-283,共8页
With the exponential development of mobile communications and the miniaturization of radio frequency transceivers, the need for small and low profile antennas at mobile frequencies is constantly growing. Therefore, ne... With the exponential development of mobile communications and the miniaturization of radio frequency transceivers, the need for small and low profile antennas at mobile frequencies is constantly growing. Therefore, new antennas should be developed to provide larger bandwidth and at the same time small dimensions. Although the gain in bandwidth performances of an antenna are directly related to its dimensions in relation to the wavelength, the aim is to keep the overall size of the antenna constant and from there, find the geometry and structure that give the best performance. The design and bandwidth optimization of a Planar Inverted-F Antenna (PIFA) were introduced in order to achieve a larger bandwidth in the 2 GHz band, using two optimization techniques based upon genetic algorithms (GA), namely the Binary Coded GA (BCGA) and Real-Coded GA (RCGA). During the optimization process, the different PIFA models were evaluated using the finite-difference time domain (FDTD) method-a technique belonging to the general class of differential time domain numerical modeling methods. 展开更多
关键词 实数编码遗传算法 平面倒F天线 带宽优化 二进制编码 有限差分时域 数值模拟方法 天线性能 优化技术
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