Error Analysis in Frequency Domain for Linear Multipass Algorithms

1. INTRoDUCTIONConsider the dyntalc systemdridt = Ax Bu (1)y = Cx Du (2)whre u is the inPut VaIable; y is the output wriab1e, and x = (x', x2,...,x")" is the state vahale. A, B, Cand D are n x n, n x r, l x n, l x r constant matrices, respectively The transfer function H(s) of equabo (1)and (2) is given bywhere H(s) and oi(i = 0, 1,..., n) are l x r matrices; pi, i = 0, 1,... 1 n are real nUIners. lt can be seen thathe sca1ar relation between every pair of input comPoneni ui and …     

高分辨力雷达导引头可编程FFT处理器设计

高分辨力雷达导引头采用先进的合成孔径雷达(SAR)进行制导,通过对回波数据的大量积累和实时处理来提高雷达的方位分辨力。其中极为关键的部件就是FFT处理器,它的处理速度是整个数字信号处理系统中的重要指标。为了研制这种高速可编程FFT处理器和满足实时处理要求。本文采用两片TMS320C25芯片设计了一种可编程FFT处理器。当运算点数在128点以内(复数数据)时,通过合理地优化可执行程序代码和安排运算数据,其编程可以达到最高的效率,能够在0.5ms完成128复数点FFT运算(全部过程)。实践表明,效果良好。     

并行实时数字仿真模型稳定性分析的扰动方法

本文讨论并行实时仿真模型的稳定性分析。建立了耦合系数扰动方法和仿真步长扰动方法。对于两类测试方程组构造了并行仿真模型,并且证明了当仿真步长适当小时,它们将具有与原连续系统相似的稳定性品质。     

一种数字滤波器系数量化处理的方法

本文提出一种数字滤波器系数量化处理的方法，它可准确模拟有限字长效应对数字系统的影响并给出优化结果，因而对数字系统的设计提供了一种有效手段。     

综合火力飞行控制系统数字仿真研究

本文对综合火力飞行控制(Integrated Fire Flight Control,简称IFFC)系统进行了数字仿真研究。做了以下三方面的工作:IFFC系统分析、IFFC系统数学建模以及IFFC系统数字仿真。表文属于IFFC系统的基础研究。这一工作对于推动我国进一步开发IFFC系统具有理论及实际价值。     

也谈"馆藏资源数字化"与"社会资源馆藏化"

“馆藏资源数字化”与“社会资源馆藏化”是数字化图书馆建设的两种模式。文章从对这两种模式概念的理解阐明了两者之间的关系，通过对我国数字化图书馆建设现状的分析，提出了实现社会资源馆藏化的具体构想。     

34.368Mb/s数字电视编码设备的研制

本文讨论了34Mb/s数字电视编码压缩方案。文中提出了利用交叉亚取样、对角滤波、二维差分编码、运动检测及帧内和帧间内插等措施,将216Mb/s速率的彩色电视信号压缩到34Mb/s。     

抽油机井热洗清蜡过程的数字仿真

本文建立了抽油机并热洗清蜡过程的数字模型，并且在热洗水各种温度压力和各种地层条件下进行了大量数字仿真。仿真结果揭示了热洗清蜡的规律，指导了热洗清蜡的最佳操作，取得很好的经济效益。     

Channel capacity and digital modulation schemes in correlated Weibull fading channels with nonidentical statistics

The novel closed-form expressions for the average channel capacity of dual selection diversity is presented, as well as, the bit-error rate (BER) of several coherent and noncoherent digital modulation schemes in the correlated Weibull fading channels with nonidentical statistics. The results are expressed in terms of Meijer's Gfunction, which can be easily evaluated numerically. The simulation results are presented to validate the proposed theoretical analysis and to examine the effects of the fading severity on the concerned quantities.     

Digital modulation classification using multi-layer perceptron and time-frequency features

Considering that real communication signals corrupted by noise are generally nonstationary, and time-frequency distributions are especially suitable for the analysis of nonstationary signals, time-frequency distributions are introduced for the modulation classification of communication signals. The extracted time-frequency features have good classification information, and they are insensitive to signal to noise ratio (SNR) variation. According to good classification by the correct rate of a neural network classifier, a multilayer perceptron (MLP) classifier with better generalization, as well as, addition of time-frequency features set for classifying six different modulation types has been proposed. Computer simulations show that the MLP classifier outperforms the decision-theoretic classifier at low SNRs, and the classification experiments for real MPSK signals verify engineering significance of the MLP classifier.