qpsk

说明：  通信信号的调制信息包含在信号的瞬时幅度、相位、频率的变化之中，不同的信号其频谱也呈现不同的特征，通过提取瞬时幅度、相位、频率以及频谱的参数统计特征，可以识别不同的通信信号。通常是利用对瞬时幅度、瞬时相位，瞬时频率和信号功率谱进行某种变换而得到可以明显区分各种信号的特征参数。(Communication signal modulation information is contained in the signal instantaneous amplitude, phase, frequency changes, the spectrum of different signals also show different characteristics, by extracting the instantaneous amplitude, phase, frequency and statistical characteristics of the parameters of the spectrum, you can identify different communication signals. Usually by the use of instantaneous amplitude, instantaneous phase, instantaneous frequency and signal power spectrum a transformation which can be clearly distinguished by the characteristic parameters of various signals.)

使用Matlab实现函数的傅里叶级数展开(Implement the function using the Matlab Fourier series expansion)

反向传播神经网络。。。。。。。。。。。。。。。。。(Backpropagation Batch。。。。。。。。。。。。。。。。。)

SGP4航天器轨道预报模型的MATLAB程序，可直接使用并对其进行二次开发。(Matlab program of SGP4 model for orbit prediction of spacecrafts.)

例1 采用动量梯度下降算法训练 BP 网络。 例2 采用贝叶斯正则化算法提高 BP 网络的推广能力。在本例中，我们采用两种训练方法，即 L-M 优化算法（trainlm）和贝叶斯正则化算法（trainbr），用以训练 BP 网络，使其能够拟合某一附加有白噪声的正弦样本数据。(Example 1 uses the momentum gradient descent algorithm to train the BP network. Example 2 uses the Bayesian regularization algorithm to improve the generalization ability of BP network. In this example, we use two training methods, the LM optimization algorithm (trainlm) and the Bayesian regularization algorithm (trainbr), to train the BP network to fit a sine sample with white noise data. )

使用MATLAB仿真，模糊自适应PID控制算法具有较好的跟踪性能、抗干扰性、鲁棒性，提高了常规PID算法的适应能力及控制精度(fuzzyPID)

用于图像精确匹配以及目标检测的SIFT算法(Sift algorithm matlab version for object detection and image match)

krige插值，主要用于地统计学的科学计算，从国外网站找到。(interpolation krige ，kriging，cokriging)

扩频通信的相关仿真文件，希望有帮助，：）(Spread Spectrum Communication Simulation related documents, hoping to help :))

当信噪比低，小信号输入时噪音严重，在整个音域的声音明显变得浑浊不清，不知发的是什么音，严重影响音质。信噪比的大小是用有用信号功率（或电压）和噪声功率（或电压）比值的对数来表示的。(When the signal to noise ratio is low, serious small signal input noise, the sound of the entire range becomes significantly turbid, I do not know what made the sound, seriously affecting the sound quality. Size is the number of the signal to noise ratio by the ratio of desired signal power (or voltage) and the noise power (or voltage) represented.)