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1.
本文基于最小均方误差(least mean square,LMS)算法自适应滤波器的基本原理,介绍了一种在Xilinx公司System Generator开发环境中采用MATLAB语言建立算法模型并在FPGA实现的设计方法。整个设计在Xilinx Virtex-5sx50tf1 136型芯片下验证。相比使用传统硬件描述语言的设计方法,MATLAB语言具有编写灵活简单易调试、设计效率高等优点。该方法不但可以很好的完成设计指标,还有效地提高了FPGA系统级设计的效率,同时降低了设计人员对硬件底层结构知识的要求。  相似文献   

2.
The Franklin Institute, Philadelphia, Pennsylvania, awarded the Benjamin Franklin Medal in Engineering to Robert E. Newnham for his invention of multiphase piezoelectric transducers and their spatial architecture which revolutionized the field of acoustic imaging. The background and significance of his research is presented. Attention is focused on the impact his research prompted in the field of medical imaging, in particular non-invasive, real-time visualization of internal tissue and organs of human body using ultrasound energy. Societal impact of Dr. Newnham's work is also pointed out.  相似文献   

3.
Synchronous data transmission systems that transmit information over dispersive channels often employ adaptive equalization techniques in the processing of the received signals. Most equalizers presently used in communication systems are of the tapped delay line (TDL) type. In this paper, we propose a class of adaptive equalizers of which the TDL equalizer is a member. Another interesting member of this class is the Laguerre adaptive equalizer which is to be introduced in this paper. The configuration of the Laguerre equalizer is developed. It is found, as shown by the examples, that the Laguerre equalizer is more accurate, and is less sensitive to timing error than the conventional TDL equalizer.  相似文献   

4.
Dr. Alexandra Navrotsky is currently a Faculty Member at the University of California, Davis, and holds a joint appointment in the Departments of Chemical Engineering; Materials Science; Chemistry; Geology; and Land, Air and Water Resources. Dr. Alexandra Navrotsky is being awarded a Franklin Medal for her work in crystal chemistry and in many different allied disciplines. Just the enormous volume of her accomplishments is award worthy. At press time she has 370 journal papers, 15 written, reviewed and/or edited books and 51 review papers and/or book chapters. Dr. Navrotsky has contributed thermodynamic data on hundreds of binary and ternary compounds, has generalized these data into concepts of bonding energies, and has used physics and chemistry to importantly contribute insights into ceramics, metallurgy, materials research, mantle petrology and, of course, crystal chemistry.  相似文献   

5.
介绍了自适应干扰消除的原理和基于LMS的自适应滤波算法,并分析了干扰抵消的频域块LMS算法,给出了算法的数学推导与模型。在宽带干扰,单音余弦干扰和线性调频干扰的条件下,利用Matlab软件进行了算法性能仿真,结果表明LMS算法可以有效地消除上述三种干扰,提高信号传输的质量。  相似文献   

6.
The Benjamin Franklin Medal in Computer and Cognitive Science is awarded to Dr. Richard M. Karp for his contributions to the understanding of computational complexity. His work helps programmers find workable solution procedures avoiding approaches that would fail to find a solution in a reasonable amount of time. Scientific, commercial, or industrial situations where his work applies include establishing least-cost schedules for industrial production, transportation routing, circuit layout, communication network design, and predicting the spatial structure of a protein from its amino acid sequencing.  相似文献   

7.
An LMS adaptive algorithm with a new step-size control equation   总被引：2，自引：0，他引：2  
In this paper, we introduce a new variable step-size LMS (VSSLMS) adaptive algorithm. The algorithm step-size equations estimate an optimal derived step-size and are controlled by only one parameter. Mean-square performance analysis is provided for zero-mean stationary Gaussian input signal, and a simple expression that predicts the algorithm steady state misadjustment is derived for small step-size fluctuations. The algorithm is compared with other well-known VSSLMS algorithms through simulation experiments, which demonstrate the performance advantages of the proposed algorithm over these algorithms.  相似文献   

8.
The Franklin Institute, Philadelphia, PA, awarded the 2004 Benjamin Franklin Medal in Mechanical Engineering to Roger Bacon for his fundamental research on the production of graphite whiskers and the determination of their microstructure and properties, for his pioneering development efforts in the production of the world's first continuously processed carbon fibers and the world's first high modulus and high-strength carbon fibers, and for his contributions to the development of carbon fibers from alternative starting materials.  相似文献   

9.
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10.
The Franklin Institute, Philadelphia, PA, awarded the 2005 Benjamin Franklin Medal in Electrical Engineering to Andrew Viterbi for developing an efficient technique that has advanced the design and implementation of modern space and wireless communication systems. He also was a leader in the development of Code Division Multiple Access wireless technologies.  相似文献   

11.
Nonlinear system identification and prediction is a complex task, and often non-parametric models such as neural networks are used in place of intricate mathematics. To that cause, recently an improved approach to nonlinear system identification using neural networks was presented in Gupta and Sinha (J. Franklin Inst. 336 (1999) 721). Therein a learning algorithm was proposed in which both the slope of the activation function at a neuron, β, and the learning rate, η, were made adaptive. The proposed algorithm assumes that η and β are independent variables. Here, we show that the slope and the learning rate are not independent in a general dynamical neural nétwork, and this should be taken into account when designing a learning algorithm. Further, relationships between η and β are developed which helps reduce the number of degrees of freedom and computational complexity in an optimisation task of training a fully adaptive neural network. Simulation results based on Gupta and Sinha (1999) and the proposed approach support the analysis.  相似文献   

12.
在海洋信道进行无线数字通信中,多径传播效应和频率选择性衰落会导致传输信号失真,信道均衡是降低这种失真的重要手段。本文将详细论述根据LMS算法的基本原理来构建自适应均衡器的过程,并通过仿真来检验该算法的效果。  相似文献   

13.
The Benjamin Franklin Medal for Physics is awarded to Dr. Deborah Jin (JILA, NIST and the University of Colorado) “in recognition of her pioneering investigations into the quantum properties of an ultra-cold gas of fermionic atoms and, in particular, for her creation of the first degenerate Fermi gas of atoms”.  相似文献   

14.
In the application of 2-D adaptive filters, a large amount of data must be processed and real-time processing is often required. In this paper, a new parallel-form realization of 2-D adaptive separable-denominator state-space filters suitable for high-speed processing is proposed. First, the 2-D local state-space model suitable for parallel processing is introduced. Next, the adaptive algorithm for this model is developed. This algorithm is based on the delayed least mean square (DLMS) method. In addition, the computation time required for the update of the coefficients is investigated. Finally, the proposed technique is applied to the design of 2-D digital filters in the spatial domain.  相似文献   

15.
The Franklin Institute, Philadelphia, Pennsylvania, awarded the 2002 Benjamin Franklin Medal in physics to Sumio Iijima for his discovery and elucidation of the atomic structure and helical character of multi- and single-wall carbon nanotubes. His pioneering work created a new, tremendously active and expanding area in the field of nanoscience and technology that involves condensed matter and material scientists, chemists and computer scientists. Iijima has also made key contributions to the mechanisms that are involved in the growth of carbon nanotubes, to the role of pentagonal and heptagonal carbon rings in the formation of caps that form at the ends of the nanotubes and to the encapsulation of molecules within the nanotubes.  相似文献   

16.
The Franklin Institute, Philadelphia, Pennsylvania, awarded the 2005 Benjamin Franklin Medal in Computer and Cognitive Science to Aravind Joshi for his fundamental contributions to natural language processing technology and to cognitive science, including particularly the development of the Tree Adjoining Grammar (TAG) family of formalisms and tractable polynomial time algorithms that analyze the complex, varied surface word orders of human languages while simultaneously recovering local elementary syntactic domains corresponding to meaning. In addition, Joshi has been a major collaborator on a new theory of discourse coherence that has influenced all subsequent work on anaphora resolution, and is currently applying TAG to address modeling problems in the life sciences.  相似文献   

17.
The fast affine projection (FAP) algorithm (Gay and Tavathia, Proceedings of the IEEE International Conference on Acoustic, Speech and Signal Processing, 1995, 3023) is known to outperform the NLMS with a slight increase in complexity, but it involves the fast calculation of the inverse of a covariance matrix of the input data that could undermine the performance of the algorithm. The block subband adaptive algorithm in (Courville and Duhamel, IEEE Trans. Signal Processing 46(9) (1998) 2359) has also illustrated significant improvement in performance over the NLMS and other frequency domain adaptive algorithms. However, it is known that block processing algorithms have lower tracking capabilities than the their sample-by-sample counterparts. In this paper, we present a sample-by-sample version of the algorithm in (Courville and Duhamel, IEEE Trans. Signal Processing 46(9) (1998) 2359) and develop a low complexity implementation of this algorithm. As a sample-by-sample algorithm, it avoids the reduced tracking capability of block algorithms. Because it does not use matrix inversion, it avoids the numerical problems of FAP algorithms. We will show that the new sample-by-sample algorithm approximates the affine projection algorithm and possesses a similar property in reducing coefficient bias that appears in monophonic and stereophonic teleconferencing when the receiving room impulse responses are undermodeled. The new fast sample-by-sample algorithm is extended for stereo acoustic echo cancellation. Simulations of echo cancellations in actual rooms are presented to verify our findings.  相似文献   

18.
在数字通信中，信道的多径传播和衰落特性常在接收端引起码间干扰（ISI）并降低信噪比，严重影响了通信质量。本文研究了空间分集与盲均衡相结合的空间分集均衡技术（SDE），提出了一种基于等增益合并和判决反馈盲均衡的空间分集均衡算法，以克服码间干扰并消除衰落对通信系统所带来的不利影响。通过计算机仿真对空间分集均衡算法和传统盲均衡算法的性能进行了对比，结果表明空间分集均衡技术优于传统的盲均衡技术，提高了数字通信性能。  相似文献   

19.
The Franklin Institute, Philadelphia, Pennsylvania, awards the 2011 Benjamin Franklin Medal in Chemistry to Professor Kyriacos C. Nicolaou for his extraordinary contributions to chemistry, biology, and medicine through the advancement of the art of synthesis as exemplified by the elegant total syntheses of some of nature's most complex biologically active molecules. Nicolaou is recognized as a world leader in the field of total synthesis for his work in chemical synthesis and chemical biology. His total syntheses are legendary, distinguished for their elegance and practicality. Among his most celebrated achievements are the total syntheses of calicheamicin γ1I, Taxol®, brevetoxin B, vancomycin, and thiostrepton. The impact of his work transcends total synthesis, for it often leads to the discovery and invention of new synthetic strategies and technologies as well as biological tools and drug candidates, thereby facilitating discoveries in biology and medicine. Nicolaou's influence on science and society extends beyond his research discoveries. Through his didactic lectures and writings, he motivates and inspires students into the sciences and informs the public about the importance of science and education to society.  相似文献   

20.
Jane Goodall is the recipient of the 2003 Benjamin Franklin Medal in Life Sciences for her long-term scientific studies of chimpanzee behavior. Not only were her studies the first of their kind, her meticulous behavioral recordings led to major changes in our understanding of the social links that exist between ourselves and our closest living relative, the chimpanzee. In discussing the importance of Dr. Goodall's work, Stephen Jay Gould (the late Alexander Agassiz Professor of Zoology at Harvard University) said ... “Science gains enormous power in replications of observations, but Homo sapiens is a single species and we can never know, by studying ourselves alone, whether important aspects of our behaviors and mental capacities reflect an ancestral evolutionary heritage (transmogrified through our uniquely evolved intelligence and its social correlates), or new features evolved or socially acquired only by our lineage. Chimpanzees are the best natural experiment we will ever have for exploring this central question, for chimps are our closest genealogical cousins and therefore hold more of our common evolutionary heritage than any other species can. Chimpanzees are not so much the shadow of man as our mirror, only slightly blurred by the mists of time”.  相似文献   

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