• Title/Summary/Keyword: QR 알고리즘

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Characteristic Analysis of Normalized D-QR-RLS Algorithm(I) (정규화된 D-QR-RLS 알고리즘의 특성 분석(I))

  • Ahn, Bong-Man;Hwang, Jee-Won;Cho, Ju-Phil
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.32 no.8C
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    • pp.782-787
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    • 2007
  • This paper presents the D(Diagonal)-QR-RLS algorithm which normalizes the fast algorithm minimizes the MSE by using Givens rotated inputs and analyzes its characteristic. This proposed one has computational complexity of O(N) and the merit that it obtains the coefficients of TDL filter directly. Although this proposed normalized algorithm has the similar form to NLMS algorithm, we can see that D-QR-RLS has superior convergence characteristic to NLMS by computer simulation.

Characteristic Analysis of Normalized D-QR-RLS Algorithm (II) (정규화된 D-QR-RLS 알고리즘의 특성 분석(II))

  • Ahn, Bong-Man;Hwang, Jee-Won;Cho, Ju-Phil
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.32 no.11C
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    • pp.1127-1133
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    • 2007
  • This paper proposes one of normalized QR-typed LMS (Least Mean Square) algorithms with computational complexity of O(N). This proposed algorithm shows the normalized property in terms of theoretical characteristics. This proposed algorithm is one of algorithms which normalize variance of input signal in terms of mean because QR-typed LMS is proportional to variance of input signal. In this paper, convergence characteristic analysis of normalized algorithm was made. Computer simulation was made by the algorithms used for echo canceller. Proposed algorithm has similar performance to theoretical value. And, we can see that proposed method shows similar one to performance of NLMS.by comparison among different algorithms.

Fast QR Factorization Algorithms of Toeplitz Matrices based on Stabilized / Hyperbolic Householder Transformations (하우스홀더 변환법을 이용한 토플리즈 행렬의 빠른 QR 인수분해 알고리즘)

  • Choi, Jae-Young
    • The Transactions of the Korea Information Processing Society
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    • v.5 no.4
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    • pp.959-966
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    • 1998
  • We present fast QR factorization algorithms $m{\times}n\;(m{\geq}n)$ Toeplitz matrix. These QR factorization algortihms are determined from the shift-invariance properties of underlying matrices. The major transformation tool is a stabilized/hyperbolic Householder transformation. The algortihms require O(mn) operations, and can be easily implemented on distributed-memory multiprocessors.

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Watermarking and QR Code in Digital Image Coding (디지털 영상 부호화에서 워터마킹과 QR 코드)

  • Im, Yong-Soon;Kang, Eun-Young
    • The Journal of the Institute of Internet, Broadcasting and Communication
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    • v.12 no.6
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    • pp.99-104
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    • 2012
  • Watermarking is one of the methods that insist on a copyright as it append digital signals in digital informations like still image, video, ets. This paper proposed a novel digital watermarking scheme which combines a QR code and a watermarking method using DCT coefficient. It proposed an algorithm for selecting a QR code from a image and to be converted into a watermark. It processed a watermarking process using expanded watermarking method in DCT area. This simulation results showed that the PSNR difference between the proposed scheme and the original image was 33.98dB and the normalized correlation between the proposed scheme and the original image was above 99.51. The proposed method is reusable.

Algorithm of Decoding the Data Codeword in Two-Dimensional QR Code (이차원 QR Code에서 데이터 코드워드의 디코딩 알고리즘)

  • Park, Kwang Wook;Lee, Jong Yun
    • Journal of the Korea Convergence Society
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    • v.4 no.4
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    • pp.21-29
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    • 2013
  • Two-dimensional QR Code has improved greatly the limits on the capacity, size, direction of the one-dimensional bar code. And it has the capacity of compressing and storing the massive amount of data and is widely used in many applications. Recently, the two-dimensional QR Code has been spread rapidly because of introducing the smart phones and increasing the amount of using them. However, there is little documentations about decoding the QR Code in which can store the large amount of information. In this paper, therefore, we present specific processing procedures and algorithms on decoding the two-dimensional QR Code and then make us understand their decoding process by explaining some examples.

A Systolic Array Structured Decision Feedback Equalizer based on Extended QR-RLS Algorithm (확장 QR-RLS 알고리즘을 이용한 시스토릭 어레이 구조의 결정 궤환 등화기)

  • Lee Won Cheol
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.29 no.11C
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    • pp.1518-1526
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    • 2004
  • In this paper, an algorithm using wavelet transform for detecting a cut that is a radical scene transition point, and fade and dissolve that are gradual scene transition points is proposed. The conventional methods using wavelet transform for this purpose is using features in both spatial and frequency domain. But in the proposed algorithm, the color space of an input image is converted to YUV and then luminance component Y is transformed in frequency domain using 2-level lifting. Then, the histogram of only low frequency subband that may contain some spatial domain features is compared with the previous one. Edges obtained from other higher bands can be divided into global, semi-global and local regions and the histogram of each edge region is compared. The experimental results show the performance improvement of about 17% in recall and 18% in precision and also show a good performance in fade and dissolve detection.

Improvement to High-Availability Seamless Redundancy (HSR) Unicast Traffic Performance Using a Hybrid Approach, QRPL (High-Availability Seamless Redundancy (HSR)의 Unicast 트래픽 성능 향상을 위한 QRPL 알고리즘)

  • Altaha, Ibraheem Raed;Rhee, Jong Myung
    • Journal of Satellite, Information and Communications
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    • v.11 no.2
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    • pp.29-35
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    • 2016
  • High-availability seamless redundancy (HSR) is a fault-tolerant protocol for Ethernet networks that provides two frame copies for each frame sent. Each copy is forwarded on a separate physical path. HSR is a potential candidate for several fault-tolerant Ethernet applications, including smart-grid communications. However, the major drawback of the HSR protocol is that it generates and circulates unnecessary frames within connected rings regardless of the presence of a destination node in the ring. This downside degrades network performance and can deplete network resources. Two simple but efficient approaches have previously been proposed to solve the above problem: quick removing (QR) and port locking (PL). In this paper, we will present a hybrid approach, QRPL, by combining QR with PL, resulting in further traffic reductions. Our analysis showed that network traffic is significantly reduced for a large-sized HSR connected ring network compared to the standard HSR protocol, QR, and PL.

Wideband Jamming Signal Remove Using Adaptive Array Algorithm (적응배열 알고리즘을 이용한 광대역 재밍 신호 제거)

  • Lee, Kwan-Hyeong
    • The Journal of Korea Institute of Information, Electronics, and Communication Technology
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    • v.12 no.4
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    • pp.419-424
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    • 2019
  • In this paper, we proposed an algorithm to estimate the desired target in wideband jamming signal environment. In order to suppress the jamming signal, we use the spatial time adaptive algorithm and QR decomposition to obtain the optimal weight. The spatial time adaptive algorithm of adaptive array antenna system multiplies the tap delay signal by a complex weight to obtain a weight. In order to minimize the power consumption because of the inverse matrix, optimal weight is obtained by using QR decomposition. Through simulation, we compare and analyze the performance of the proposed algorithm and the existing algorithm. In the target estimation of [-40o,0o,+40o], the proposed algorithm estimated all three targets, but the existing algorithm estimated only [0o] due to of the jamming signal. We prove that the proposed algorithm improves performance by removing the jamming signal and estimating the target accurately.

Efficient Sampling of Graph Signals with Reduced Complexity (저 복잡도를 갖는 효율적인 그래프 신호의 샘플링 알고리즘)

  • Kim, Yoon Hak
    • The Journal of the Korea institute of electronic communication sciences
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    • v.17 no.2
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    • pp.367-374
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    • 2022
  • A sampling set selection algorithm is proposed to reconstruct original graph signals from the sampled signals generated on the nodes in the sampling set. Instead of directly minimizing the reconstruction error, we focus on minimizing the upper bound on the reconstruction error to reduce the algorithm complexity. The metric is manipulated by using QR factorization to produce the upper triangular matrix and the analytic result is presented to enable a greedy selection of the next nodes at iterations by using the diagonal entries of the upper triangular matrix, leading to an efficient sampling process with reduced complexity. We run experiments for various graphs to demonstrate a competitive reconstruction performance of the proposed algorithm while offering the execution time about 3.5 times faster than one of the previous selection methods.

Convergence Decision Method Using Eigenvectors of QR Iteration (QR 반복법의 고유벡터를 이용한 수렴 판단 방법)

  • Kim, Daehyun;Lee, Jingu;Jeong, Seonghee;Lee, Jaeeun;Kim, Younglok
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.41 no.8
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    • pp.868-876
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    • 2016
  • MUSIC (multiple signal classification) algorithm is a representative algorithm estimating the angle of arrival using the eigenvalues and eigenvectors. Generally, the eigenvalues and eigenvectors are obtained through the eigen-analysis, but this analysis requires high computational complexity and late convergence time. For this reason, it is almost impossible to construct the real-time system with low-cost using this approach. Even though QR iteration is considered as the eigen-analysis approach to improve these problems, this is inappropriate to apply to the MUSIC algorithm. In this paper, we analyze the problems of conventional method based on the eigenvalues for convergence decision and propose the improved decision algorithm using the eigenvectors.