共查询到19条相似文献,搜索用时 484 毫秒
1.
利用矢量分析的方法实现CNC刀具半径补偿功能,最基础的工作是进行转接类型的判断,本文阐述了一种通过计算矢量点积、叉积判断转接类型方法,并在VC++6.0中实现了该算法。 相似文献
2.
3.
传统的单电磁矢量传感器(UEMVS)由3个电偶极子和3个磁环构成且方向图是全向的。但是当多个单电磁矢量传感器依附在共形载体上构成共形电磁矢量传感器阵列时,为了降低共形电磁矢量传感器阵列的副瓣,通常每个传感器的方向图是有向的。基于有向方向图的单电磁矢量传感器也称为单有向电磁矢量传感器(UDEMVS)。该文针对UDEMVS的参数估计问题,提出两种参数估计方法,分别是基于免搜索的旋转不变信号参数估计和矢量叉积(ESPRIT-VCP)方法以及基于网格搜索的多重信号分类和最小瑞利商(MUSIC-MRQ)方法。ESPRIT-VCP方法是根据旋转不变性和矢量叉积,获得4维参数的闭式解,MUSIC-MRQ方法根据信号和噪声子空间正交性与最小瑞利商,利用网格搜索得到2维角度估计值,进而结合信号回波模型得到2维极化的估计值。所提两种方法只利用了UDEMVS的6通道数据就能有效得到目标的参数估计结果,有较低的计算复杂度。仿真结果从角度和极化的估计性能出发验证了所提方法的有效性。 相似文献
4.
利用电磁矢量传感器来实现信号多参数的联合估计是近年来信号处理领域的一种新的方法和途径。基于单个电磁矢量传感器通过构造两组具有固定时延的接收数据,利用TLSESPRIT算法和矢量叉积相结合实现了多参数的联合估计,参数自动完成配对,可以最多同时估计5个不相关的信号,且空间到达角、极化参数的估计和信号频率的估计是两个相互独立的过程互不影响,与利用极化敏感阵列进行参数估计相比计算量小,并通过计算机仿真验证了此方法的有效性。 相似文献
5.
提出一种不需要载波同步的调制识别方法,能够实现二进相移键控(BPSK)、正交相移键控(QPSK)和八进相移键控(8PSK)的识别。其方法是:首先对带有残余载波的基带信号进行定时抽样,计算抽样点的点积及叉积,并将点、叉积复合成一个复基带调相信号,其特点是调制阶数与原信号相同,而残余载波转换为固定相位;然后,利用这个复基带信号的四阶累积量构造分类向量进行分类。首先介绍四阶累积量的基本概念;然后给出相移键控(PSK)信号的表达形式,点叉积计算方法及其组合而成的复基带信号的形式;其次介绍识别算法;最后进行仿真分析,并考察了符号长度、定时误差及成形因子对分类性能的影响。 相似文献
6.
王中德(1989)推广了矩阵直积,给出了矩阵第二类直积和第三类直积运算,并将此运算应用于正交变换的构造。本文进一步推广了王中德(1989)的结果,提出了一种矩阵分块直积运算,并以此来构造正交变换。 相似文献
7.
该文提出了一种基于2维矢量接收阵列的双基地MIMO雷达系统多目标ADOD(Azimuth Direction Of Departure),ADOA(Azimuth Direction Of Arrival)和EDOA(Elevation Direction Of Arrival)联合估计算法。雷达发射端采用均匀标量线阵,接收端将常规矢量阵元的每个电磁偶极子相互分离构成2维接收阵列。算法通过张量因子分解获取各流形矩阵,并利用ESPRIT算法估计目标的ADOD。文中给出了接收阵列的一种特定阵元排列方式,并改进了矢量叉积法用于估计目标的2D-DOA。与传统方法相比,该文所用阵列结构可通过扩展接收阵列孔径提高雷达的角度估计性能,相互分离的偶极子弱化了传统矢量阵的天线互耦效应。相应算法避免了谱峰搜索,能够自动配对,仿真实验证明了算法的有效性。 相似文献
8.
利用积分模(度量)研究模糊系统对可积函数类的逼近性是人们普遍关注的方法,而基于K-拟算术运算诱导的Kp-积分模不仅是一维积分模的推广,而且是刻画p-次可积函数类的重要工具.本文通过引入拟减运算重新定义Kp-积分模,且在Kp-积分模意义下讨论分片线性函数对一类ûp-可积函数的逼近性,进而构造性地证明广义Mamdani模糊系统对ûp-可积函数类仍有逼近性.最后通过实例分析说明广义Mamdani模糊系统的逼近效果.结果表明广义Mamdani模糊系统可以按任意精度逼近一类ûp-可积函数. 相似文献
9.
硫化镉薄膜的制备新技术 总被引:1,自引:0,他引:1
CdS 是用于制作太阳电池和光电探测器等的Ⅱ—Ⅵ族化合物半导体材料之一。CdS薄膜制备方法有蒸发,溅射,化学汽相淀积等。实验证明其特性与制备方法有关,本文重点介绍 MOCVD 和离化淀积法制备 CdS 薄膜及其特性分析。 相似文献
10.
本文对叉积自动频率控制算法进行了研究,该算法常用来辅助载波抑制环来实现对大频偏信号的跟踪,而叉积自动频率控制算法在频偏估计的过程中,往往会造成一定的系统时延.针对这个问题,本文给出了一种解决方法,仿真结果表明此法在保持一定同步精度的同时,延迟时间被极大地缩短. 相似文献
11.
The central issue on designing channel of distribution is vertical integration. Will manufacturer distribute products by itself or by independent retail trader? It has different answer about this question. Some documents focuses on two different manufacturers that produce the products with relevant demand. Does the manufacturer select forward direction integration or employ exclusive retail trader? Their channel choice will determine the balanced price and balanced incomes. McGuire and Stael… 相似文献
12.
本文通过对剥容的金属化聚碳酸酯薄膜电容器的半成品和成品后绝缘性能的不良品进行再一次赋能,成功地提高了剥容产品的绝缘性能和耐压试验后绝缘性能的稳定性,从而使得产品的绝缘合格率有了明显的提高。 相似文献
13.
14.
当我们进入21世纪,计算机技术必不可少,计算机技术应用于产品设计,让设计更合理也更完美,最大程度上的符合产品的基本特征,计算机技术为产品设计与发展提供了平台,可以让产品设计的本质利用计算机技术挖掘出来,产品设计风格让人们的生活变得多姿多彩,产品设计是社会发展的重中之重,也是物质产品生产的必备程序之一。产品的优劣主要是由产品设计体现的,计算机使产品设计更加程序化、产业化,极大地丰富了产品物质。怎么样在现代社会中将计算机与产品设计相结合,并对产品设计进行更新与创新,是社会各界都在关注的问题。运用先进的科技,把计算机同产品设计相结合,才能够让计算机在产品设计中的应用发挥巨大的作用,从而丰富我们的工作和生活,让我们的物质生活更人性化、可持续化。 相似文献
15.
Silicon technology has now advanced to the point that there is a serious mismatch in the time taken to design advanced silicon-based systems and the time to market for any new product or product derivative. To obviate this delay, a new paradigm is emerging based on intellectual property (IP) exchange, where designers and differing companies share subsystems (virtual cores) between themselves to reduce design time to acceptable levels. To this end, over 150 companies including all the major players formed the Virtual Socket Interface Alliance in March 1997. The protection of IP has become a serious issue as intercompany subsystem design exchange becomes more commonplace. This paper presents new techniques to protect the IP of virtual cores that implement digital signal processing (DSP) algorithms. The approach involves embedding codewords into the design of fundamental signal processing algorithms such as digital filters and the DFT in such a way that proof of authorship can be retained, and, if required, easily identified. The techniques discussed can be adapted to protect other fundamental DSP algorithms such as convolution and correlation. The protection of IP via watermarking techniques is increasingly being applied at all levels of design. It is particularly advantageous if such techniques are applied at the highest abstraction levels in the design flow, and if such techniques are applied at basic algorithm level, they become very difficult to detect at lower levels of system design 相似文献
16.
S.S Reddi 《Signal processing》1984,7(1):45-56
This paper presents a proof for an important eigenvector property of Toeplitz matrices. The property, a variant of Caratheodory's theorem, is that the zeroes of the polynomials formed from eigenvectors with unique maximum/minimum eigenvalues of a positive definite Toeplitz matrix are distinct and lie on the unit circle. The proof is based on simple matrix-theoretical results and offers an insight that is lacking in existing proofs. A representation form for Toeplitz matrices is obtained and this form is used for justification of Pisarenko's spectral analysis based on eigenvectors/eigenvalues of the covariance matrix. The theoretical groundwork developed for the proof of the eigenvector property is then used to compare Pisarenko's null eigenvector technique with Burg's maximum entropy analysis, and arguments are presented in favor of the former technique. 相似文献
17.
18.
Elad M. Bruckstein A.M. 《IEEE transactions on information theory / Professional Technical Group on Information Theory》2002,48(9):2558-2567
An elementary proof of a basic uncertainty principle concerning pairs of representations of R/sup N/ vectors in different orthonormal bases is provided. The result, slightly stronger than stated before, has a direct impact on the uniqueness property of the sparse representation of such vectors using pairs of orthonormal bases as overcomplete dictionaries. The main contribution in this paper is the improvement of an important result due to Donoho and Huo (2001) concerning the replacement of the l/sub 0/ optimization problem by a linear programming (LP) minimization when searching for the unique sparse representation. 相似文献