检索结果-内蒙古大学图书馆

lr algorithm based on MED for multi-input-multi-output LDs

IET COMMUNICATIONS 2017年第9期11卷 1477-1484页

作者： Song, Yunchao Liu, Chen Lu, Feng Nanjing Univ Posts & Telecommun Sch Elect Sci & Engn Nanjing Jiangsu Peoples R China

Recently, lattice reduction (lr)-aided linear detectors (LDs) are shown to be very effective in multi-input-multi-output systems for low-complexity and small bit-error-rate (BER) performance. However, the lr algorithms in the previous lr-aided LDs mainly aim to improve the orthogonality of the channel matrix where only channel state information is used. In this study, the authors design a novel lr algorithm to enhance the BER performance of the lr-aided LDs. Unlike the previous lr algorithms, the proposed lr algorithm aims to decrease the modified Euclidean distance (MED) in the lr-aided LDs, whereas the MED utilises the received signal as well as the channel matrix. Note that the MED is directly related to the BER performance of the lr-aided LDs, thus decreasing the MED in the lr-aided LDs can help to reduce the BER of the lr-aided LDs. In the proposed lr algorithm, the partial column addition operation is used. The simulation results indicate that their lr-aided LDs exhibit smaller BER than the previous lr-aided LDs. Moreover, the computational complexity is also shown in the simulation results.

关键词： MIMO communication error statistics matrix algebra lr algorithm MED lattice reduction-aided linear detectors multiinput-multioutput systems small bit-error-rate performance BER channel matrix orthogonality channel state information modified Euclidean distance lr-aided LDs received signal partial column addition operation computational complexity multiinput-multioutput LDs

来源：评论

学校读者我要写书评

暂无评论

Rutishauser's lr algorithm and Bruhat iteration

引用

LINEAR & MULTILINEAR ALGEBRA 2015年第10期63卷 2061-2070页

作者： Thompson, Mary Clair Tam, Tin-Yau Lafayette Coll Dept Math Easton PA 18042 USA Auburn Univ Dept Math & Stat Auburn AL 36849 USA

Rutishauser's lr algorithm is extended in the context of semisimple Lie group. Explicit examples are given.

关键词： lr algorithm semisimple Lie group Bruhat decomposition Bruhat iteration complete multiplicative Jordan decomposition

来源：评论

学校读者我要写书评

暂无评论

Motion blurred image restoration based on flight control system 37

Motion blurred image restoration based on flight control sys...

引用

37th Chinese Control Conference (CCC)

作者： Zhao, Ran Liu, Dongliang Qu, Feng Zhang, Xu Hangzhou Dianzi Univ Acad Automat Hangzhou 310018 Peoples R China Wolong Elect CO LTD Shangyu 312300 Peoples R China

ISBN: (纸本)9789881563958

In recent years, the applications of Aerial UAV are more and more extensive. The aerial system is subject to the impact of the relative movement, posture changes and the atmosphere, which results in low clarity of the captured image. Based on the image blur phenomenon caused by UAV flight, a function is introduced as its coefficient in Lucy-Richardson (lr) image restoration algorithm, which could effectively protect edge details of the image. The results of image quality evaluation show that the improved lr algorithm can effectively suppress the noise in the image and improve the clarity of the image.

关键词： Flight control system image restoration Motion blur lr algorithm Evaluation of Image quality

来源：评论

学校读者我要写书评

暂无评论

Motion blurred image restoration based on flight control system

Motion blurred image restoration based on flight control sys...

引用

第37届中国控制会议

作者： Ran Zhao Dongliang Liu Feng Qu Xu Zhang Academy of Automation Hangzhou Dianzi University Wolong Electric CO. LTD

In recent years, the applications of Aerial UAV are more and more extensive. The aerial system is subject to the impact of the relative movement, posture changes and the atmosphere, which results in low clarity of the captured image. Based on the image blur phenomenon caused by UAV flight, a function is introduced as its coefficient in Lucy-Richardson（lr） image restoration algorithm, which could effectively protect edge details of the image. The results of image quality evaluation show that the improved lr algorithm can effectively suppress the noise in the image and improve the clarity of the image.

关键词： Flight control system image restoration Motion blur lr algorithm Evaluation of Image quality

来源：评论

学校读者我要写书评

暂无评论

Fast computation of eigenvalues of companion, comrade, and related matrices

引用

BIT NUMERICAL MATHEMATICS 2014年第1期54卷 7-30页

作者： Aurentz, Jared L. Vandebril, Raf Watkins, David S. Washington State Univ Dept Math Pullman WA 99164 USA Katholieke Univ Leuven Dept Comp Sci B-3001 Heverlee Belgium

The class of eigenvalue problems for upper Hessenberg matrices of banded-plus-spike form includes companion and comrade matrices as special cases. For this class of matrices a factored form is developed in which the matrix is represented as a product of essentially 2x2 matrices and a banded upper-triangular matrix. A non-unitary analogue of Francis's implicitly-shifted QR algorithm that preserves the factored form and consequently computes the eigenvalues in O(n (2)) time and O(n) space is developed. Inexpensive a posteriori tests for stability and accuracy are performed as part of the algorithm. The results of numerical experiments are mixed but promising in certain areas. The single-shift version of the code applied to companion matrices is much faster than the nearest competitor.

关键词： Polynomial Root Companion matrix Comrade matrix lr algorithm

来源：评论

学校读者我要写书评

暂无评论

From qd to lr, or, how were the qd and lr algorithms discovered?

引用

IMA JOURNAL OF NUMERICAL ANALYSIS 2011年第3期31卷 741-754页

作者： Gutknecht, Martin H. Parlett, Beresford N. ETH Seminar Appl Math CH-8092 Zurich Switzerland Univ Calif Berkeley Dept Math Berkeley CA 94720 USA

Perhaps, the most astonishing idea in eigenvalue computation is Rutishauser's idea of applying the lr transform to a matrix for generating a sequence of similar matrices that become more and more triangular. The same idea is the foundation of the ubiquitous QR algorithm. It is well known that this idea originated in Rutishauser's qd algorithm, which precedes the lr algorithm and can be understood as applying lr to a tridiagonal matrix. But how did Rutishauser discover qd and when did he find the qd-lr connection? We checked some of the early sources and have come up with an explanation.

关键词： matrix eigenvalues qd algorithm lr algorithm QR algorithm Rutishauser

来源：评论

学校读者我要写书评

暂无评论

A Cholesky lr algorithm for the positive definite symmetric diagonal-plus-semiseparable eigenproblem

引用

LINEAR ALGEBRA AND ITS APPLICATIONS 2008年第2-3期428卷 586-599页

作者： Plestenjak, Bor Van Barel, Marc Van Camp, Ellen Univ Ljubljana Dept Math SI-1000 Ljubljana Slovenia Katholieke Univ Leuven Dept Comp Sci B-3001 Heverlee Belgium

We present a Cholesky lr algorithm with Laguerre's shift for computing the eigenvalues of a positive definite symmetric diagonal-plus-semiseparable matrix. By exploiting the semiseparable structure, each step of t... 详细信息

关键词： diagonal-plus-semiseparable matrix lr algorithm Laguerre's method Cholesky decomposition

来源：评论

学校读者我要写书评

暂无评论

Generalized qd algorithm and Markov-Bernstein inequalities for Jacobi weight

引用

NUMERICAL algorithmS 2009年第4期51卷 429-447页

作者： Draux, Andr Moalla, Borhane Sadik, Mohamed INSA Rouen Dept Genie Math F-76131 Mont St Aignan France Acad Mil Fondouk Jedid 8012 Tunisia

The Markov-Bernstein inequalities for the Jacobi measure remained to be studied in detail. Indeed the tools used for obtaining lower and upper bounds of the constant which appear in these inequalities, did not work, since it is linked with the smallest eigenvalue of a five diagonal positive definite symmetric matrix. The aim of this paper is to generalize the qd algorithm for positive definite symmetric band matrices and to give the mean to expand the determinant of a five diagonal symmetric matrix. After that these new tools are applied to the problem to produce effective lower and upper bounds of the Markov-Bernstein constant in the Jacobi case. In the last part we com pare, in the particular case of the Gegenbauer measure, the lower and upper bounds which can be deduced from this paper, with those given in Draux and Elhami (Comput J Appl Math 106:203-243, 1999) and Draux (Numer Algor 24:31-58, 2000).

关键词： Orthogonal polynomials Jacobi polynomials Gegenbauer polynomials Markov-Bernstein inequalities qd algorithm lr algorithm

来源：评论

学校读者我要写书评

暂无评论

A more accurate algorithm for computing the Christoffel transformation

引用

JOURNAL OF COMPUTATIONAL AND APPLIED MATHEMATICS 2007年第1期205卷 567-582页

作者： Bueno, Maria I. Dopico, Froilan M. Coll William & Mary Dept Math Williamsburg VA 23187 USA Univ Carlos III Madrid Dept Matemat Leganes 28911 Spain

A monic Jacobi matrix is a tridiagonal matrix which contains the parameters of the three-term recurrence relation satisfied by the sequence of monic polynomials orthogonal with respect to a measure. The basic Christoffel transformation with shift a transforms the monic Jacobi matrix associated with a measure d mu into the monic Jacobi matrix associated with (x - alpha) d mu. This transformation is known for its numerous applications to quantum mechanics, integrable systems, and other areas of mathematics and mathematical physics. From a numerical point of view, the Christoffel transformation is essentially computed by performing one step of the lr algorithm with shift, but this algorithm is not stable. We propose a more accurate algorithm, estimate its forward. errors, and prove that it is forward stable, i.e., that the obtained forward errors are of similar magnitude to those produced by a backward stable algorithm. This means that the magnitude of the errors is the best one can expect, because it reflects the sensitivity of the problem to perturbations in the input data. (C) 2006 Elsevier B.V. All rights reserved.

关键词： Christoffel transformation forward stability roundoff error analysis lr algorithm

来源：评论

学校读者我要写书评

暂无评论

The relation between the QR and lr algorithms

引用

SIAM JOURNAL ON MATRIX ANALYSIS AND APPLICATIONS 1998年第2期19卷 551-555页

作者： Xu, HG Fudan Univ Dept Math Shanghai 200433 Peoples R China

For an Hermitian matrix the QR transform is diagonally similar to two steps of the lr transforms. Even for non-Hermitian matrices the QR transform may be written in rational form.

关键词： QR algorithm lr algorithm triangular factorization Cholesky factorization

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：