bpcheb

说明：  在matlab中，对ldpc的编码和译码功能进行实现(LDPC encoding and decoding)

详细讲述了直接序列扩频差分锁相环的文章，包含具体的算法结构，并附有仿真结果。(A novel differentially coherent delay-locked loop(DCDLL) for accurate code tracking is proposed for direct sequence spread spectrum systems. Due to the use of the differential decoder and exactly one correlator, the proposed scheme avoids the problems of gain imbalance. The tracking error variance is derived by linear analysis. When the proposed DCDLL scheme is applied in ranging with additive white Gaussian noise (AWGN) channel, the performance of the proposed DCDLL scheme is about 1.4 dB better than that of one-correlator tau–dither loop (TDL), and near that of noncoherent DLL.)

计算分形维数()

Acquisition of Glonass satellites signals

变频信号的快速FFT变换，能准确的给出信号的频谱特征(Fast FFT of the signal frequency, can give accurate spectral characteristics of the signal)

Photonic crystals are attractive optical materials for controlling and manipulating the flow of light. One dimensional photonic crystals are already in widespread use in the form of thin-film optics with applications ranging from low and high reflection coatings on lenses and mirrors to colour changing paints and inks. Higher dimensional photonic crystals are of great interest for both fundamental and applied research, and the two dimensional ones are beginning to find commercial applications. The first commercial products involving two-dimensionally periodic photonic crystals are already available in the form of photonic-crystal fibers, which use a microscale structure to confine light with radically different characteristics compared to conventional optical fiber for applications in nonlinear devices and guiding exotic wavelengths. The three-dimensional counterparts are still far from commercialization but may offer additional features such as optical nonlinearity require

基于反向传播神经网络(Back Propagation, BP)的数据分类简单应用(Simple application of data classification based on Back Propagation (BP))

对一个给定的状态转移矩阵求其联合分布矩阵，联合熵，平均互信息量以及共熵。可以画出平均互信息量的曲线(For a given state transition matrix of their joint distribution matrix, the joint entropy, mutual information and the average total entropy. Can draw the curve of the average mutual information)

数值分析的实验，拉格朗日、分段线性、三次样条等(Analysis of the experiment, Lagrangian, piecewise linear, cubic spline, etc.)

对正弦波信号进行混频，分解，采用傅立叶变换来分析其频率(Mixing of sinusoidal signals, decomposition, using Fourier transform to analyze the frequency)