fft

分别设计理想低通滤波器、巴特沃思滤波器、指数滤波器、梯形低通滤波器,并对含高斯噪声的图像进行低通滤波，截止频率自选，观察不同的截止频率,不同的滤波器的滤波效果。(Were designed for the ideal low pass filter, Butterworth filter, exponential filter, ladder low-pass filter, and Gaussian noise images with low-pass filter cutoff frequency chosen to observe the different cut-off frequency, different filter filtering device.)

matlab书籍，做关于粒子群优化算法时可能会用到(matlab books, done on the particle swarm optimization algorithm may be used)

图像插值算法有三种：最近邻插值、双线性插值和双三次插值，这里有前两种插值算法的matlab程序(Image interpolation algorithm has three: nearest neighbor interpolation, bilinear interpolation and bicubic interpolation, here are the first two interpolation algorithm matlab program)

编写了MATLAB程序生产和扩频码进行仿真，仿真程序从发送方完成通道的接收端，得出在不同的扩频码，在不同的信噪比即误码率的图形比较直接序列扩频通信系统原理，改善系统性能的度(Written MATLAB program to produce and direct sequence spread spectrum communication system principle of spreading codes for simulation, emulation program to complete the channel from the sender to the receiver end, draw graphics comparison at different spreading code, the bit error rate under different SNR i.e., the degree of improvement of the system performance)

基于映射广义弹性系数的电网静态稳定快速评估判据(Rapid Quantitative Method for Power System Static Stability Assessment Based on Mapping General Elastic Coefficient)

说明：  采用FDTD计算2维光子晶体的散射和透射的可执行程序小软件(Calculated using FDTD 2-D photonic crystal scattering and transmission of the executable program small software)

Variable step size Afine Projection, adaptive filter algorithm

8载gsm ddc实例 matlab实例 (8gsm ddc)

用遗传算法来对简单的一元函数进行优化，带有GUI窗口，简单方便(Using genetic algorithms to optimize the simple functions of one variable, with a GUI window, easy)

说明：  首先，建立两个模拟信号的数学模型 有用信号 干扰信号。两个信号的中心频率、信号带宽等参数由学生自己选定，要求两个信号的频谱不重叠 分别画出三个模拟信号的时域波形和频谱图；然后，根据x_a (t)的中心频率和带宽，按照奈奎斯特采样定理选择采样频率fs，分别对信号s_a1 (t)、s_a2 (t)、x_a (t)进行时域采样，得到离散信号s_1 (n)、s_2 (n)、x(n)。利用FFT算法分析离散信号的频谱，分别画出三个离散信号的时域波形和频谱图； 接着，设计数字滤波器H(z)，要求该滤波器对干扰信号s_2 (n)的衰减大于40dB。提出滤波器的设计指标，并设计滤波器，给出滤波器的设计结果，绘制滤波器的幅频特性和相频特性曲线，验证滤波器的设计结果是否达到设计指标要求；此外，选择实现数字滤波器H(z)的结构，画出滤波器结构信号流图；然后，将合成信号x(n)输入数字滤波器H(z)，按照所选择的滤波器结构，设计计算机程序计算滤波器的输出响应y(n)，画出y(n)的时域波形和频谱图；(the synthetic signal x (n) is input into the digital filter H (z). According to the selected filter structure, a computer program is designed to calculate the output response y (n) of the filter, and the time-domain waveform and spectrum diagram of Y (n) are drawn)