chapter02_ex

说明：  MATLAB编程进行频谱分析研究,考虑各种情况的结果和图形分析(MATLAB programming spectrum analysis, considering all the circumstances and graphical analysis of the results)

重要的模拟程序，模拟精度很高，值得大家好好参考，好好学习一下(Important simulation, the simulation accuracy is high, is worth a good reference to learn about)

提取音频信号的带宽，matlab源代码，仅供参考 (Extract audio signal bandwidth, matlab source code, for reference only)

共轭梯度法是介于最速下降法与牛顿法之间的一个方法，它仅需利用一阶导数信息，但克服了最速下降法收敛慢的缺点，又避免了牛顿法需要存储和计算Hesse矩阵并求逆的缺点，共轭梯度法不仅是解决大型线性方程组最有用的方法之一，也是解大型非线性最优化最有效的算法之一。(Conjugate gradient method is between the steepest descent method and Newton method between a method that only use the first derivative information, but the steepest descent method to overcome the disadvantage of slow convergence, but also avoids the need to store and calculate Newton Hesse matrix and the shortcomings of the inverse, conjugate gradient method is not only linear equations to solve large-scale one of the most useful, large-scale nonlinear optimization solution is also the most efficient algorithms.)

插值法求出阶跃响应的Ts，Tr，deta，性能指标。方法准确，简单(interpolation step response is calculated by the Ts, Tr, deta, performance indicators. The method is accurate and simple)

一种自适应的均值滤波代码，加入了自适应的阈值T(An adaptive mean filtering code, adding the adaptive threshold T)

MATLAB处理实验数据(MATLAB process experimental data )

说明：  本程序基于MATLAB设计了数字滤波器实现的对含有噪声的文件的过滤(The program is based on MATLAB implementation of a digital filter paper with noise filtering)

电力系统发生三相对称短路时用MATLAB进行潮流计算，计算短路电流和短路电压(Symmetrical three-phase short circuit occurs, the power system with MATLAB for flow calculation, calculation of short-circuit current and short-circuit voltage)

用七元线形天线阵（ULA） 已知：信号中心波长为2,天线阵元的间距为1米,快拍数为2000，空中有四个 源信号,假设它们的频率：0.015, 0.05, 0.02, 0.035 四个源信号的方向分别为：pi/4 pi/3 pi/6 3pi/4 求： 1）在不加入噪声的情况下,画出传统波束形成法、Bartlett波束 形成法、Capon波束形成法的空间谱图； 2）在加入高斯白噪声的情况下,假设信噪比为10dB，画出传统波束 形成法、Bartlett波束形成法、Capon波束形成法的空间谱图。(7-element linear antenna array (ULA) Known: the signal center wavelength is 2, the antenna element spacing of 1 m, the number of snapshots for 2000, the air there are four Source signal, assuming that their frequency: 0.015, 0.05, 0.02, 0.035 The direction of the four source signals: pi/4 pi/3 pi/6 3pi/4 Requirements: 1) not to join the noise, to draw the traditional beam-forming method, Bartlett, beam Formation method, Capon beamforming method of the space spectrum 2) by adding Gaussian white noise, assuming that the SNR is 10dB, to draw the traditional beam Formation method, Bartlett, beamforming, Capon beamforming method of the space spectrum.)