• Title/Summary/Keyword: code sequence

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A Design of Index/XML Sequence Relation Information System for Product Abstraction and Classification (산출물 추출 및 분류를 위한 Index/XML순서관계 시스템 설계)

  • Sun Su-Kyun
    • The KIPS Transactions:PartD
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    • v.12D no.1 s.97
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    • pp.111-120
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    • 2005
  • Software development creates many product that class components, Class Diagram, form, object, and design pattern. So this Paper suggests Index/XML Sequence Relation information system for product abstraction and classification, the system of design product Sequence Relation abstraction which can store, reuse design patterns in the meta modeling database with pattern Relation information. This is Index/XML Sequence Relation system which can easily change various relation information of product for product abstraction and classification. This system designed to extract and classify design pattern efficiently and then functional indexing, sequence base indexing for standard pattern, code indexing to change pattern into code and grouping by Index-ID code, and its role information can apply by structural extraction and design pattern indexing process. and it has managed various products, class item, diagram, forms, components and design pattern.

Reed Solomon Encoding System of 4-state Bar Code for Automatic Processing in Mail Items (우편물 자동처리를 위한 4-state 바코드 Reed Solomon 인코딩 시스템)

  • 박문성;송재관;황재각;남윤석
    • Proceedings of the IEEK Conference
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    • 2000.11c
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    • pp.47-50
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    • 2000
  • Recently many efforts on the development of automatic processing system for delivery sequence sorting have been performed in ETRI , which requires the use of postal 4-state bar code system to encode delivery points. The 4-state bar code called postal 4-state bar code for high speed processing that has been specifically designed for information processing of logistics and automatic processing of the mail items. This paper describes a method of Reed-Solomon encoding for creating error correction codeword of 4-state bar code.

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Polyphase Signature Sequences for M-ary Phase Signaling (M진 위상 신호 방식에 효과적인 다상 서명 수열)

  • Park, So-Ryoung;Song, Iick-Ho
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.32 no.11C
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    • pp.1059-1065
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    • 2007
  • In this paper, we propose a class of polyphase signature sequences, whose general odd correlation properties are useful for M-ary phase signaling systems. The maximum magnitude of the general odd correlation functions of the proposed sequences are investigated and compared with those of FZC (Frank-Zadoff-Chu) sequences and those of EOE (equivalent odd and even correlation) sequences. The performance of the asynchronous M-ary phase signaling systems using the proposed sequences is simulated and compared with that using FZC sequences in direct sequence code division multiple access (DS/CDMA) systems. The performance of the system using the proposed sequence is shown to be better than that using FZC sequences when the multipath fading is in existence.

Code Acquisition with Receive Diversity and Constant False Alarm Rate Schemes: 2. Nonhomogeneous Fading Circumstance (수신기 다양성과 일정 오경보 확률 방법을 쓴 부호획득: 2. 벼균질 감쇄 환경)

  • Kwon Hyoung-Moon;Kang Hyun-Gu;Park Ju-Ho;Ahn Tae-Hoon;Lee Sung-Ro;Song Iick-Ho
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.31 no.7C
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    • pp.725-734
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    • 2006
  • As a sequel to Part 1, the performance characteristics of the cell averaging (CA), greatest of (GO), and smallest of (SO) constant false alarm rate (CFAR) processors in nonhomogeneous environment are obtained and compared when receiving antenna diversity is employed in the pseudonoise (PN) code acquisition of direct-sequence code division multiple access (DS/CDMA) systems. Unlike in homogeneous environment, the GO CFAR processor is observed to exhibit the best performance in nonhomogeneous environment, with the CA CFAR processor performing the second best.

High-Efficiency and Low-Complexity Spread Spectrum ALOHA for Machine-to-Machine Communications (사물지능 통신을 위한 고효율 저복잡도 대역 확산 알로하 기법)

  • Noh, Hong-jun;Park, Hyung-won;Lim, Jae-sung
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.41 no.12
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    • pp.1700-1706
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    • 2016
  • To improve the number of simultaneous transmissions of machine-to-machine traffic in a spread spectrum ALOHA channel, we propose a new spreading technique called doubly truncated cyclic code shift keying (DTCCSK). By truncating the codeset of cyclic code shift keying, DTCCSK freely adjusts the spreading factor and the symbol length. As a result, DTCCSK exhibits both a high spectral efficiency of M-ary signaling and low implementation complexity of a direct sequence.

Analysis on the Power Spectrum of Direct Sequence-Time Hopping UltraWideBand System (DS-TH UWB 시스템의 전력 스펙트럼 분석)

  • Kim Young-Chul;Lee Jeong-suk;Kang Duk-Keun
    • Journal of Digital Contents Society
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    • v.5 no.3
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    • pp.219-224
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    • 2004
  • In This paper, we have analyzed the power spectrum of DS-TH Ulhawideband (Direct Sequence-Time Hopping UWB) system which used pseudo-noise (PN) code. The DS-TH UWB system proposed in this paper multiplies the information signal with PN code to construct pulse train with random pattern and then the chips in pulse train are bundled into several groups to map to the particular value. The (+)/(-) pulse is tented in the time slot of frame by comparing a particular value with timing information that was stored in the lookup table. Thus, the energy spark (Comb Line) which is generated certainly in convantional system can be suppressed efficiently by PN code. And we knew that the proposed DS-TH UWB System even could have very smoothing power spectrum ctaracteristic without applying high speed Time-Hopping code.

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ON SEQUENCE OF FUNCTIONS

  • Salehbhai, Ibrahim A.;Prajapati, Jyotindra C.;Shukla, Ajay K.
    • Communications of the Korean Mathematical Society
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    • v.28 no.1
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    • pp.123-134
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    • 2013
  • Operational techniques have drawn the attention of several researchers in the study of sequence of functions and polynomials. An attempt is made to introduce a new sequence of functions by using operational techniques. Some generating relations and finite summation formulae have been obtained. The corresponding MAPLE code for obtaining above sequence of functions for different values of parameters was also discussed.

Improved Blind Multipath Estimation for Long Code DS-CDMA

  • Yu Qian;Bi Guoan;Zhang Gaonan
    • Journal of Communications and Networks
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    • v.7 no.3
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    • pp.278-283
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    • 2005
  • This paper proposes a blind channel estimation scheme for long code direct sequence code division multiple access (DS­CDMA) systems with multipath fading channels. This scheme combines the advantages of Toeplitz displacement and correlation matching methods to achieve improved performance. The basic idea is to remove the effects of noise and interferences with Toeplitz displacement operation and then estimate the multi path channel parameters with the correlation matching method. Simulation results are presented to show that the proposed scheme provides better MSE performance and robustness against the near-far problem.

Minimization Method of Reading Error in Postal 4 State Bar Code Reader (우편용 4 State 바코드시스템의 판독오차 최소화 방법)

  • 황재각;신미영;박문성
    • Proceedings of the IEEK Conference
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    • 1999.11a
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    • pp.1027-1030
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    • 1999
  • Recently many efforts on the development of automatic processing system for delivery sequence sorting have been performed in ETRI, which requires the use of postal 4 state bar code system to encode delivery points. This paper addresses the issue on the reduction of reading error in postal 4 state raster beam based bar code reader by adjusting measured values of bar code width to its average value over each interval. The test results show that the above method reduces the average reading error rate approximately by 90-100%.

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A Study on the Generating Algorithm and the Correlation Function of Kumar Code Sequences for the Frequency Hopping Patterns (주파수 경로 패턴을 위한 Kumar 부호계열 발생 알고리즘 및 상관함수 특성에 관한 연구)

  • 이정재;한영렬
    • Journal of the Korean Institute of Telematics and Electronics
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    • v.26 no.12
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    • pp.1886-1902
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    • 1989
  • In this paper we discuss the generating algorithm of Kumar code sequences which are based on generalized bent sequences for FH-CDMA. The code sequence generator was constructed for the shift register stages n=4 over GF (5). Finally we analyze the characteristics fo Hamming correlation between two code sequences and the time-frequency correlatins of the complete waveform with the sinusoidal chips as the elemental waveforms.

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