复FIR数字滤波器幅值约束Chebyshev设计

L.J.Karam和McClellan最早得到了有关复数域Chebyshev逼近的复交错点组定理,并提出了以此定理为基础的复Remez算法用于复FIR数字滤波器的Chebyshev设计.本文首先给出并证明了复交错点组定理在带不等式约束条件下的扩展定理,之后,根据此扩展定理中对最优解极值频率点特性的描述,提出了一种有效的算法来解决带幅值不等式约束的复FIR数字滤波器的Chebyshev设计问题.这一新算法中还结合了复Remez算法及赖晓平提出的迭代Remez算法,并且如果问题的解存在则保证收敛到此解.作者把上述算法做成了MATLAB语言程序,并进行了大量的实例设计实验,仿真结果表明此算法有效而可靠.     

用微波电桥测量有耗物质复介电常数的一种算法

本文导出了用微波电桥测量物质复介电常数时,加载波导段的传输系数。给出了一种迭代算法。测量了纯水的复介电常数,和公认的数值甚为一致。     

基于空时联合抗干扰算法的复矩阵求逆

针对卫星导航接收机易被干扰的特点,研究了空时联合抗干扰算法,并提出了一种简化的复正定厄米矩阵求逆实现方法。首先,给出了空时联合抗干扰算法的基本模型。随后,在详细分析传统复正定厄米矩阵求逆算法基础上,给出了改进的复正定厄米矩阵求逆方法的具体步骤。最后,基于数字信号处理（DSP）的硬件平台,对运算量进行了对比分析。仿真结果表明,改进的复正定厄米矩阵求逆方法加法和乘法运算量都大幅度降低,比传统算法运算速度加快了三分之一。算法简单可靠,易于实现,适用于工程应用中实时性要求较高的场合。     

SAR回波信号模拟器幅相误差实时校正方法

合成孔径雷达(SAR)回波信号模拟器不可避免地存在通道幅相误差,会影响对雷达点目标成像性能的准确评估,因此对模拟器幅相误差实时校正具有重要意义。由于模拟器系统传递函数不具有共轭对称性,要满足在实时工作模式下用硬件实现幅相误差校正,既要求收敛速度快,又要求优化性能好,就需要采用一种快速有效的算法来设计复系数FIR滤波器。提出了复Remez算法和遗传算法相结合的复系数FIR滤波器设计方法,最后给出用此方法实现SAR回波信号模拟器幅相误差校正的实例。     

带约束的复FIR数字滤波器Chebyshev设计算法

本文主要讨论了复FIR数字滤波器的频域不等式约束Chebyshev设计问题.作者首先把文献[1]中的复交错点组定理扩展到有不等式约束的情况,之后根据扩展定理中对最优解特性的描述,并结合复Remez算法[1]及赖晓平的迭代Remez算法[2][3],提出了一种有效的算法来解决频域带不等式约束的复FIR数字滤波器的Chebyshev设计问题.如果问题的解存在,则算法能保证收敛到最优解.作者用MATLAB语言对上述算法进行了实现并做了仿真分析.     

用复系数数字FIR滤波器实现超宽带正交解调接收系统的幅相误差校正

本文首先对影响正交解调结构超宽带接收系统性能的幅相误差作了简要分析,随后提出了用复系数FIR滤波器实现整个系统幅相误差校正的方案,并推导出一种设计幅相校正FIR滤波器的算法,最后给出了一个用此方案实现超宽带系统幅相误差校正的实例.     

通信网频率分配算法设计

主要给出了一种实用化的频率分配算法描述、设计思想及具体实现,并给出了该算法的应用范围及领域。     

由幅度谱恢复最小相位信号的改进复倒谱算法

本文给出了有限长实序列幅度谱的内插公式,提出了一种由幅度谱恢复最小相位信号的改进复倒谱算法,该方法可明显地提高恢复精度、降低运算量。     

基于拟牛顿算法的复自适应均衡器的设计

介绍了一种新的拟牛顿算法，这种算法的收敛速度与RLS算法相当，但稳定性要比RLS算法好，误码率要比LMS算法低，详述了基于该算法的复自适应均衡器的软硬件设计与实现。     

工业控制环境中QRCode的检测和识别算法

以QR Code为例,研究工业控制环境中的二维条码检测和识别技术.首先针对光照不均,利用Retinex理论,处理光照校正.然后根据QR Code条码的特征,提出了基于边缘信息的二值分割算法,并设计了一种快速定位算法.接着分析了条码图像经过高斯函数模糊的数学模型,求解高斯函数方差,并给出了利用逆滤波对条码图像进行反模糊复...     

Convergence properties and stationary points of a perceptronlearning algorithm

An analysis of the stationary (convergence) points of an adaptive algorithm that adjusts the perceptron weights is presented. This algorithm is identical in form to the least-mean-square (LMS) algorithm, except that a hard limiter is incorporated at the output of the summer. The algorithm is described in detail, a simple two-input example is presented, and some of its convergence properties are illustrated. When the input of the perceptron is a Gaussian random vector, the stationary points of the algorithm are not unique and they depend on the algorithm step size and the momentum constant. The stationary points of the algorithm are presented, and the properties of the adaptive weight vector near convergence are discussed. Computer simulations that verify the analysis are given     

Distributed algorithms for computing shortest pairs of disjointpaths

Distributed algorithms for finding two disjoint paths of minimum total length from each node to a destination are presented. The algorithms have both node-disjoint and link-disjoint versions and provide each node with information sufficient to forward data on the disjoint paths. It is shown that this problem can be reduced to the problem of finding a minimal shortest path from each node to the destination in a modified network, and a distributed algorithm on the original network that simulates a shortest-paths algorithm running on the modified network is presented. The algorithm has a smaller space complexity than any previous distributed algorithm for the same problem, and a method for forwarding packets is presented that does not require any additional space complexity. A synchronous implementation of the algorithm is also presented and studied     

A comparison of several vector quantization codebook generationapproaches

A review and a performance comparison of several often-used vector quantization (VQ) codebook generation algorithms are presented. The codebook generation algorithms discussed include the Linde-Buzo-Gray (LBG) binary-splitting algorithm, the pairwise nearest-neighbor algorithm, the simulated annealing algorithm, and the fuzzy c-means clustering analysis algorithm. A new directed-search binary-splitting method which reduces the complexity of the LBG algorithm, is presented. Also, a new initial codebook selection method which can obtain a good initial codebook is presented. By using this initial codebook selection algorithm, the overall LBG codebook generation time can be reduced by a factor of 1.5-2.     

一个符号神经网络的学习算法

本文首先根据神经科学和认知科学的研究，提出了一种符号神经网络结构，该结构溶符号机制和神经网络于一体，然后在此基础上研究了其学习算法，该算法结合神经网络ＢＰ学习算法和符号机制中学习算法的特点；最后通过实验，证实该算法的可行性和先进性。     

Image restoration using a modified Hopfield network

A modified Hopfield neural network model for regularized image restoration is presented. The proposed network allows negative autoconnections for each neuron. A set of algorithms using the proposed neural network model is presented, with various updating modes: sequential updates; n-simultaneous updates; and partially asynchronous updates. The sequential algorithm is shown to converge to a local minimum of the energy function after a finite number of iterations. Since an algorithm which updates all n neurons simultaneously is not guaranteed to converge, a modified algorithm is presented, which is called a greedy algorithm. Although the greedy algorithm is not guaranteed to converge to a local minimum, the l (1) norm of the residual at a fixed point is bounded. A partially asynchronous algorithm is presented, which allows a neuron to have a bounded time delay to communicate with other neurons. Such an algorithm can eliminate the synchronization overhead of synchronous algorithms.     

Time domain algorithm for the estimation of two sinusoidalfrequencies

A computationally simple algorithm is presented that measures one or two frequencies using lookup tables and simple adders. The algorithm is based on a real-time processing of instantaneous frequency and envelope. The algorithm provides a maximum likelihood estimate in the single frequency case. Oversampling is required and the algorithm cannot estimate three or more frequencies. A complete error analysis is presented along with simulation results     

某雷达数字化调平平台建模及算法

建立一种雷达数字化调平平台的数学模型,并提出了相应的算法。传统的坐标旋转变换的算法复杂、实现困难、运算量大,因此提出一种全新的算法,该算法针对三维的数学模型进行等价拆解为二维模型,进行平面几何解析,通过分析,总结出几个简单的公式,使得算法简单,便于理解。该模型可应用于相控阵雷达和火炮射击等未进行机械调平的多个领域。     

基于图聚集算法的寄存器传输级ALU工艺映射算法

给出了寄存器传输级工艺映射(RTLM)算法,该方法支持使用高层次综合和设计再利用的现代VLSI设计方法学,允许复杂的RT级组件,尤其是算术逻辑单元(ALU)在设计中重用.首先提出了ALU的工艺映射问题,给出了源组件和目标组件以及标准组件的定义,在此基础上通过表格的方式给出映射规则的描述.映射算法套用一定的映射规则用目标ALU组件来实现源ALU组件.采用一种基于分支估界法的图聚集算法,用该算法不仅可以产生面积最优的,而且还可以产生延时最优的设计.针对不同库的实验结果证明该算法对于规则结构的数据通路特别有效.     

采用精确时延模型基于路径的缓冲器插入时延优化

提出了一种基于路径的缓冲器插入时延优化算法,算法采用高阶模型估计连线时延,用基于查表的非线性时延模型估计门延迟.在基于路径的时延分析基础上,提出了缓冲器插入的时延优化启发式算法.工业测试实例实验表明,该算法能够有效地优化电路时延,满足时延约束.     

Comments on "An Efficient SS/TDMA Time Slot Assignment Algorithm"

The time slot assignment algorithm presented in the above paper needs certain improvements for it to be an efficient one. In this correspondence, the necessary improvements are incorporated and an improved SS/TDMA time slot assignment algorithm is presented. The new algorithm is compared to the old one and the computer simulation exhibits a better performance of the present algorithm.