检索结果-内蒙古大学图书馆

MODIFIED viterbi algorithm FOR A JITTER-DOMINANT 1-D2 CHANNEL

IEEE TRANSACTIONS ON MAGNETICS 1992年第5期28卷 2895-2897页

作者： ZENG, WN MOON, J The Center for Micromagnetics and Information Technologies Department of Electrical Engineering University of Minnesota Minneapolis MN USA

One way to improve data capacity in magnetic recording is to increase linear density by storing magnetic transitions more closely in each track. However, experiments have shown that one drawback of such practice is the substantial increase of transition noise. Transition noise will degrade the performance of the detector, and, thus, reduce reliability of the reproduced information. Random jitter in the transition position is believed to be one of the major contributions to transition noise. Transition noise cannot be modeled as additive noise since it is data-dependent. In this paper, we propose a new detection scheme which yields better performance than the conventional viterbi detector in jitter-dominant recording channels. The proposed detection scheme is based on the Gaussian jitter assumption, and is very similar to the viterbi algorithm (VA) except that a modified branch error metric is used to incorporate the data-dependent nature of jitter noise. Error rate simulation results, obtained for channels dominated by either Gaussian jitter or truncated Gaussian jitter, show that the proposed detection scheme yields lower error rates than the VA.

关键词： viterbi algorithm Jitter Additive noise Working environment noise Detectors Gaussian noise Error analysis Magnetic noise Degradation Moon

来源：评论

学校读者我要写书评

暂无评论

APPLICATION OF THE viterbi algorithm TO THE DETECTION OF COMPACT SPECTRUM

引用

IEEE TRANSACTIONS ON MAGNETICS 1986年第5期22卷 1200-1202页

作者： FRENCH, CA WOLF, JK Center for Magnetic Recording Research University of California San Diego La Jolla CA USA

A viterbi detector is described-for detection of the ternary compact spectrum output waveform presented by Veillard [1]. The performance of the detector with additive noise is compared by simulation, to threshold detection of the same waveform. It is demonstrated that the implementation of the viterbi algorithm for this case is relatively simple. The viterbi detector presented is shown to produce a lower bit error rate than theshold detection for a given amount of additive noise. It is also shown that 4-bit quantization before viterbi detection is sufficient to produce results essentially the same as those obtained without quantization.

关键词： viterbi algorithm Detectors Additive noise Quantization Magnetic recording Bit error rate Filters Decoding Magnetic modulators Partial response channels

来源：评论

学校读者我要写书评

暂无评论

COMPARISON OF DECODING algorithmS FOR TRELLIS CODED MODULATION USING viterbi algorithm IN THE PRESENCE OF INTERSYMBOL INTERFERENCE

引用

ELECTRONICS LETTERS 1988年第9期24卷 541-542页

作者： ZOU, G WEINRICHTER, H Tech. Univ. Wien

The letter describes a comparison of some receiver structures suitable for trellis-coded modulation on channels causing intersymbol interference. Simulation results show that a viterbi decoder treating trellis coding and intersymbol interference as one compound encoding mechanism yields the best performance, which at Pb=10-4 is about 6 dB in S/N better than any other receiver structure

关键词： viterbi algorithm compound encoding mechanism decoding decoding algorithms digital communication system digital communication systems intersymbol interference intersymbol interference modulation receiver structures simulation trellis coded modulation

来源：评论

学校读者我要写书评

暂无评论

Survivor memory reduction in the viterbi algorithm

引用

IEEE COMMUNICATIONS LETTERS 2005年第4期9卷 352-354页

作者： Abbasfar, A Yao, K Univ Calif Los Angeles Dept Elect Engn Los Angeles CA 90024 USA

This paper presents a novel approach for implementation of the viterbi algorithm, wherein survivor paths are generally kept in as low as one half of the storage required for traditional trace-back methods. Survivor memory reduction is obtained by storing only the useful part of the survivor paths. In other words, the redundancy in the survivor paths is removed. A decoder using this approach not only requires significantly less memory, but also runs faster than conventional decoders. Some instances of this approach are explicitly presented.

关键词： convolutional code viterbi algorithm survivor memory trace-back method

来源：评论

学校读者我要写书评

暂无评论

Two-Dimensional Soft Output viterbi algorithm with a Variable Reliability Factor for Holographic Data Storage

引用

JAPANESE JOURNAL OF APPLIED PHYSICS 2013年第9期52卷 09LE03-09LE03页

作者： Koo, Keunhwi Kim, Soo-Yong Jeong, Jae Jin Kim, Sang Woo Pohang Univ Sci & Technol POSTECH Dept Elect Engn Pohang 790784 Gyeongbuk South Korea Samsung Elect Co Ltd M&C Dev Team Syst LSI Div Yongin 446711 Gyeonggi South Korea Pohang Univ Sci & Technol POSTECH Dept Creat IT Excellence Engn Pohang 790784 Gyeongbuk South Korea Pohang Univ Sci & Technol POSTECH Future IT Innovat Lab Pohang 790784 Gyeongbuk South Korea

In a practical holographic data storage system, the reconstruction process for a data page should account for the processing time as well as the bit error rate (BER) performance. To improve both aspects, we introduce two-dimensional (2D) partial response maximum likelihood composed of a 2D partial response (PR) target including diagonal elements and a 2D soft output viterbi algorithm (SOVA) with a variable reliability factor. The 2D SOVA performs two one-dimensional (1D) SOVAs in structural accordance with the 2D PR target where extrinsic information uses the expected value calculated on a synchronization pattern. Finally, the 2D SOVA exports a weighted average using the reliability factor that is updated similarly as the optimization scheme for each page. The simulation results show that the proposed method has superior BER performance, despite using only two 1D SOVAs as compared with the modified 2D SOVA composed of four 1D SOVAs. (c) 2013 The Japan Society of Applied Physics

关键词： Data Storage EXPECTATION VALUE Partial Response Maximum Likelihood Weighted Average viterbi algorithm bit error rate performance processing time reliability coefficient Data Page holographic data storage system

来源：评论

学校读者我要写书评

暂无评论

RECOGNITION OF DISTORTED PATTERNS USING THE viterbi algorithm

引用

IEEE TRANSACTIONS ON PATTERN ANALYSIS AND MACHINE INTELLIGENCE 1982年第1期4卷 18-25页

作者： TANAKA, H HIRAKAWA, Y KANEKU, S NIPPON TELEGRAPH & TEL PUBL CORP MUSASHINO ELECT COMMUN LAB MUSASHINO TOKYO 180 JAPAN KAGOSHIMA UNIV DEPT ELECTR KAGOSHIMA 890 JAPAN

In this paper a new recognition system of distorted patterns is presented, where the viterbi algorithm and a modified trellis incorporating a pertinent statistics of distorted patterns are used. The system works in a manner quite similar to our own human decision process. The trellis is so constructed that it can eliminate all the irrelevant pattern classes at the outset and leave only the most probable for its fimal decision, yielding a great economy of processing time and the accuracy of decision. The method was applied to recognition of handwritten English letters and Japanese Katakana"s with success. The method is also universal and can be applied to any category of distorted pattems.

关键词： Pattern recognition viterbi algorithm Hamming distance Statistics Humans Handwriting recognition Stochastic processes Pattern classification Computer applications Dynamic programming Author Keywords viterbi algorithm Distorted pattern recognition handwritten letter Markov property stochastic pattern classification trellis

来源：评论

学校读者我要写书评

暂无评论

A High-throughput Parallel viterbi algorithm via Bitslicing

引用

ACM TRANSACTIONS ON PARALLEL COMPUTING 2021年第4期8卷 1–25页

作者： Monfared, Saleh Khalaj Hajihassani, Omid Mohsseni, Vahid Rahmati, Dara Gorgin, Saeid Inst Res Fundamental Sci IPM Tehran Iran Univ Alberta Edmonton AB Canada Shahid Beheshti Univ SBU Comp Sci & Engn Dept Tehran Iran Iranian Res Org Sci & Technol IROST Tehran Iran

In this work, we present a novel bitsliced high-performance viterbi algorithm suitable for high-throughput and data-intensive communication. A new column-major data representation scheme coupled with the bitsliced architecture is employed in our proposed viterbi decoder that enables the maximum utilization of the parallel processing units in modern parallel accelerators. With the help of the proposed alteration of the data scheme, instead of the conventional bit-by-bit operations, 32-bit chunks of data are processed by each processing unit. This means that a single bitsliced parallel viterbi decoder is capable of decoding 32 different chunks of data simultaneously. Here, the viterbi's Add-Compare-Select procedure is implemented with our proposed bitslicing technique, where it is shown that the bitsliced operations for the viterbi internal functionalities are efficient in terms of their performance and complexity. We have achieved this level of high parallelism while keeping an acceptable bit error rate performance for our proposed methodology. Our suggested hard and soft-decision viterbi decoder implementations on GPU platforms outperform the fastest previously proposed works by 4.3x and 2.3x, achieving 21.41 and 8.24 Gbps on Tesla V100, respectively.

关键词： CUDA viterbi algorithm convolutional codes bitslicing HPC

来源：评论

学校读者我要写书评

暂无评论

A CONTINUOUS-TIME DYNAMIC FORMULATION OF viterbi algorithm FOR ONE-GAUSSIAN-PER-STATE HIDDEN MARKOV-MODELS

引用

SPEECH COMMUNICATION 1993年第4期12卷 321-333页

作者： SAERENS, M UNIV LIBRE BRUXELLES IRIDIA LAB CP 194-6 50 AV F ROOSEVELT B-1050 BRUSSELS BELGIUM

When using hidden Markov models for speech recognition, it is usually assumed that the probability that a particular acoustic vector is emitted at a given time only depends on the current state and the current acoustic vector observed. In this paper, we introduce another idea, i.e., we assume that, in a given state, the acoustic vectors are generated by a continuous Markov process. Indeed, the time evolution of the acoustic vector is inherently dynamic and continuous, and sampling only occurs for the purpose of computation. This allows us to assign a probability density to the time trajectory of the acoustic vector inside the state, reflecting the probability that this particular path has been generated by the continuous Markov process associated with this state. Roughly speaking, it measures the ''adequacy'' of the observed trajectory with respect to an ideal trajectory, which is modelled by a vectorial linear differential equation. This model is introduced in order to describe the dynamic behaviour of the acoustic vector inside a state. Once the segmentation is fixed, reestimation formulae for the parameters of the continuous Markov process are derived for the viterbi algorithm. As usual, the segmentation can be obtained by sampling the continuous process, and by applying dynamic programming to find the best path over all the possible sequences of states and all the possible durations. Finally, we sketch a possible generalization to path mixtures, for which different trajectories are available in each state. However, we have to stress that no experimental results are available at present. Indeed, we did not have the opportunity to test the algorithm on real speech. We are aware of the fact that the assumptions we did may not be appropriate for the modelling of speech.

关键词： SPEECH RECOGNITION HIDDEN MARKOV MODELS viterbi algorithm

来源：评论

学校读者我要写书评

暂无评论

EXPERIMENTS IN TEXT RECOGNITION WITH THE MODIFIED viterbi algorithm

引用

IEEE TRANSACTIONS ON PATTERN ANALYSIS AND MACHINE INTELLIGENCE 1979年第2期1卷 184-193页

作者： SHINGHAL, R TOUSSAINT, GT MCGILL UNIV SCH COMP SCI MONTREAL H3C 3G1 QUEBEC CANADA

In this paper a modification of the viterbi algorithm is formally described, and a measure of its complexity is derived. The modified algorithm uses aheuristic to limit the search through a directed graph or trellis. The effectiveness of the algorithm is investigated via exhaustive experimentation on an input of machine-printed text. The algorithm assumes language to be a Markov chain and uses transition probabilities between characters. The results empirically answer the long-standing question of what is the benefit, if any, of using transition probabilities that depend on the length of a word and their position in it.","doi":"10.1109/TPAMI.1979.4766904","publicationTitle":"IEEE Transactions on Pattern Analysis and Machine Intelligence","startPage":"184","endPage":"193","rightsLink":"http://***/AppDispatchServlet?publisherName=ieee&publication=0162-8828&title=Experiments+in+Text+Recognition+with+the+Modified+viterbi+algorithm&isbn=&publicationDate=April+1979&author=Rajjan+Shinghal&ContentID=10.1109/TPAMI.1979.4766904&orderBeanReset=true&startPage=184&endPage=193&volumeNum=PAMI-1&issueNum=2","displayPublicationTitle":"IEEE Transactions on Pattern Analysis and Machine Intelligence","pdfPath":"/iel5/34/4766893/***","keywords":[{"type":"IEEE Keywords","kwd":["Text recognition","viterbi algorithm","Dictionaries","Costs","Computer science","Error correction","Councils","Probability","Decoding","Dynamic programming"]},{"type":"Author Keywords ","kwd":["text recognition","Computational complexity","contextual information","cost","feature vector","N-gram probabilities","probability of misclassification"]}],"allowComments":false,"pubLink":"/xpl/***?punumber=34","issueLink":"/xpl/***?isnumber=4766893","standardTitle":"Experiments in Text Recognition with the Modified viterbi algorithm

关键词： Text recognition viterbi algorithm Dictionaries Costs Computer science Error correction Councils Probability Decoding Dynamic programming Author Keywords text recognition Computational complexity contextual information cost feature vector N-gram probabilities probability of misclassification

来源：评论

学校读者我要写书评

暂无评论

EVALUATION OF DECISION FEEDBACK EQUALIZATION AND viterbi algorithm DETECTION FOR VOICEBAND DATA-TRANSMISSION .2.

引用

IEEE TRANSACTIONS ON COMMUNICATIONS 1976年第11期24卷 1238-1245页

作者： FALCONER, DD MAGEE, FR BELL TEL LABS INC HOLMDELNJ 07733

This paper describes experimental results of simulated 12000 and 14400 bits/s quadrature amplitude-modulated (QAM) systems (which were described in detail in Part I [1] ) operating on real and simulated voiceband channels. These experimental results show that both viterbi algorithm detection and decision feedback equalization allow digital data transmission at symbol rates exceeding the nominal bandwidth capabilities of typical telephone channels. It is demonstrated in these experiments that the viterbi algorithm receiver structure tested is less affected by linear distortion than the decision feedback receiver but exhibits greater sensitivity to phase jitter. On conditioned voiceband channels where there may be substantial phase jitter, a reasonable compromise between sensitivity to distortion and noise and sensitivity to phase jitter is made by a modem employing decision feedback equalization and decision-directed carrier phase tracking.

关键词： Decision feedback equalizers viterbi algorithm Jitter Phase distortion Quadrature amplitude modulation Data communication Bandwidth Telephony Testing Phase noise

来源：评论

学校读者我要写书评

暂无评论

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

请选择保存的检索档案：

请选择收藏分类：

通借通还

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：