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51.
Mohammad Niaboli Guilani Gholamreza Ardeshir 《International Journal of Circuit Theory and Applications》2019,47(11):1762-1774
A high-order discrete-time IIR low-pass with complex poles using charge sampling is presented in a single-stage structure by using a mathematical strategy. In comparison with the analog complex-poles Gm-C filters, the proposed filter consumes lower power and has good linearity, and all of the tunings are implemented only by capacitor sizes. The proposed filter is a seventh-order Butterworth, but this method can be generalized to implement other complex pole filters like Tchebyshev and Elliptic. Post-layout simulation results in 130-nm complementary metal-oxide-semiconductor (CMOS) show an IIP3 of +18 dBm and a noise figure of 5 dB. The filter has a rejection of more than 110 dB in its stop band and consumes 1.5 mW with a 1.6-V supply voltage, and circuit occupies an about 0.12 mm2 of silicon. 相似文献
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53.
详细研究了在Visual Basic6.0环境下如何设计IIR数字滤波器。即利用发展相当成熟的模拟滤波器的理论、设计方法和严格的设计公式来设计滤波器。先根据给定技术指标求出模拟滤波器的传输函数,再转换成数字滤波器的传输函数。以低通,带通、带阻、高通数字滤波器为例,用脉冲响应不变法和双线性变换法两种转换方法来实现巴特沃斯、切比雪夫滤波器。利用Visual Basic设计了IIR数字滤波器并进行仿真,可随时调整参数对比滤波器特性,快速得到仿真结果,直观方便,极大地减轻了工作量,提高了工作效率。 相似文献
54.
研究了乙烯醋酸乙烯酯共聚物(EVA)/EPDM/IR三元共混和EVA/EPDM/IR/IR四元共混发泡材料的性能。在EVA中混入EPDM可使发泡材料的拉伸强度、撕裂强度和粘合强度提高,而收缩率和压缩永久变形降低;在EVA中混入IR除具备混入EPDM同样的优点外,还可提高发泡材料的柔性;IR的混入可改善发泡材料二次热压成型制品的表面清晰度。 相似文献
55.
Y. V. Joshi S. C. Dutta Roy 《International Journal of Circuit Theory and Applications》1998,26(5):499-507
A new method for designing IIR multiple notch filters is presented, which satisfies the notch frequency specifications exactly and realizes 3 dB rejection bandwidths which are lower than those specified. An allpass filter-based realization has been worked out to make the design relatively insensitive to coefficient inaccuracies. Illustrative examples are given. © 1998 John Wiley & Sons, Ltd. 相似文献
56.
R. Lpez-Valcarce F. Prez-Gonzlez 《International Journal of Adaptive Control and Signal Processing》1998,12(6):467-494
A novel off-line procedure for IIR system identification problems has been recently proposed and analysed under the assumption of a white input signal. The method happens to have a single, unbiased stationary point under this condition. This approach is based in interpolation theory and tries to overcome the drawbacks of equation- and output-error strategies. Here it is shown that the unicity of the stationary point is still preserved for a wider class of input signals, namely autoregressive processes of a certain order. With coloured input signals, an SPR condition arises for the convergence of the original on-line algorithm. A modification is proposed that eliminates this SPR condition, while leaving the stationary point untouched. Two different structures that implement the on-line algorithm are presented; the use of a lattice structure for the implementation of the recursive part of the filter is considered as well. © 1998 John Wiley & Sons, Ltd. 相似文献
57.
设计IIR数字滤波器的遗传优化算法 总被引:2,自引:0,他引:2
提出了IIR数字滤波器设计的遗传优化法。这是一种模拟自然遗传和达尔文进化理论的随机并行优化算法。首先,详细描述了遗传算法并给出了计算步骤,然后将遗传算法用于IIR数字滤波器的优化设计,最后给出了模拟计算结果。 相似文献
58.
59.
This paper deals with the application of Chebychevʼs approximation theory to IIR digital filter frequency response (FR) approximation. It explores the properties of the frequency response of IIR digital filters as a nonlinear complex approximating function; IIR digital filter frequency response is used to approximate a prescribed magnitude and phase responses. The approximation problem is closely related to optimization. If the set of approximating functions is non-convex, the optimization problem is difficult and may converge to a local minimum. The main results presented in the paper are proposing a convex stability domain by introducing a condition termed “sign condition” and characterization of the best approximation by the Global Kolmogorovʼs Criterion (GKC). The Global Kolmogorovʼs Criteria is shown to be also a necessary condition for the approximation problem. Finally, it is proved that the best approximation is a global minimum. The sign condition can be incorporated as a constraint in an optimization algorithm. 相似文献
60.
Stock market prediction is of great interest to stock traders and investors due to high profit in trading the stocks. A successful stock buying/selling generally occurs near price trend turning point. Thus the prediction of stock market indices and its analysis are important to ascertain whether the next day's closing price would increase or decrease. This paper, therefore, presents a simple IIR filter based dynamic neural network (DNN) and an innovative optimized adaptive unscented Kalman filter for forecasting stock price indices of four different Indian stocks, namely the Bombay stock exchange (BSE), the IBM stock market, RIL stock market, and Oracle stock market. The weights of the dynamic neural information system are adjusted by four different learning strategies that include gradient calculation, unscented Kalman filter (UKF), differential evolution (DE), and a hybrid technique (DEUKF) by alternately executing the DE and UKF for a few generations. To improve the performance of both the UKF and DE algorithms, adaptation of certain parameters in both these algorithms has been presented in this paper. After predicting the stock price indices one day to one week ahead time horizon, the stock market trend has been analyzed using several important technical indicators like the moving average (MA), stochastic oscillators like K and D parameters, WMS%R (William indicator), etc. Extensive computer simulations are carried out with the four learning strategies for prediction of stock indices and the up or down trends of the indices. From the results it is observed that significant accuracy is achieved using the hybrid DEUKF algorithm in comparison to others that include only DE, UKF, and gradient descent technique in chronological order. Comparisons with some of the widely used neural networks (NNs) are also presented in the paper. 相似文献