zhixin_aolgrithm

Cornell大学一篇关于OFDM仿真的论文（含matlab程序 (Cornell University of an article on OFDM simulation papers (including matlab program)

本书的目的是让读者熟练掌握MATLAB的知识并用来求解工程问题。解决这类问题一般需要编写相对较短、使用次数较少的程序。因此，本书将着重介绍在MATLAB中如何有效地开发简洁易读的程序，同时使之具有易于调试和执行速度快的特点。(The purpose of this book is to allow readers to master knowledge of MATLAB and used to solve engineering problems. To solve such problems usually need to write a relatively short period, the use of fewer procedures. Therefore, this book will focus on how to effectively develop in MATLAB concise, easy-to-read program, so that it has easy debugging and execution speed.)

GPS学习最全的matlab程序，望大家学习交流(GPS to study the most complete matlab program, hope you learn from the exchange of)

qpsk modulation and demodulation

实现心电信号的提取，为后续心电信号的处理做准备(ECG extraction, to prepare for the follow-up processing of the ECG)

lorenz bifurcation diagram with matlab programm

说明：  不同导频长度(6,10,20)情况下的信道估计程序，(Different pilot length (6,10,20) in case of channel estimation procedures)

1 SIFT 发展历程 SIFT算法由D.G.Lowe 1999年提出，2004年完善总结。后来Y.Ke将其描述子部分用PCA代替直方图的方式，对其进行改进。 2 SIFT 主要思想 SIFT算法是一种提取局部特征的算法，在尺度空间寻找极值点，提取位置，尺度，旋转不变量。 3 SIFT算法的主要特点： a) SIFT特征是图像的局部特征，其对旋转、尺度缩放、亮度变化保持不变性，对视角变化、仿射变换、噪声也保持一定程度的稳定性。 b) 独特性(Distinctiveness)好，信息量丰富，适用于在海量特征数据库中进行快速、准确的匹配[23]。 c) 多量性，即使少数的几个物体也可以产生大量SIFT特征向量。 d) 高速性，经优化的SIFT匹配算法甚至可以达到实时的要求。 e) 可扩展性，可以很方便的与其他形式的特征向量进行联合。 4 SIFT算法步骤： 1） 检测尺度空间极值点 2） 精确定位极值点 3） 为每个关键点指定方向参数 4） 关键点描述子的生成 本包内容为sift算法matlab源码(1 SIFT course of development SIFT algorithm by DGLowe in 1999, the perfect summary of 2004. Later Y.Ke its description of the sub-part of the histogram with PCA instead of its improvement. 2 the SIFT main idea The SIFT algorithm is an algorithm to extract local features in scale space to find the extreme point of the extraction location, scale, rotation invariant. 3 the main features of the SIFT algorithm: a) SIFT feature is the local characteristics of the image, zoom, rotate, scale, brightness change to maintain invariance, the perspective changes, affine transformation, the noise also maintain a certain degree of stability. b) unique (Distinctiveness), informative, and mass characteristics database for fast, accurate matching [23]. c) large amounts, even if a handful of objects can also produce a large number of SIFT feature vectors. d) high-speed and optimized SIFT matching algorithm can even achieve real-time requirements. e) The scalability can be very convenient fe)

matlab基本语法，对初学者非常有帮助(matlab basic syntax is very helpful for beginners)

Reads a ply file (text format). ply files can be in binary format as well this function can read ply files in txt format only e.g. created by makePly.m.