ME_EDDR_final_code

说明：  一个小程序，用于模拟电磁波在三维空间传播，在MATLAB平台开发。(A small program used to simulate the spread of electromagnetic waves in three-dimensional space, in the MATLAB platform.)

for compression using discrete cosine transform

energy efficiency computation when wireless body area sensor node communicates to the coordinator through wireless link in the presence of a relay node when the distance is varied

Image enchancement techniques available for the features extraction

Compression DICOM images using different method according to region of interest (ROI)

说明：  最经典的图像置乱，用于图像置乱，图像加密。。。。。。。。。。。。。。。。。。。。。。。。。(arnold permutation for image encryption)

这里面有两个程序，两个都是采用4QAM调制。不过个人觉得第一个更容易懂，因为写的很有条理。我改的那个程序就是根据这个来的。 不过在这里面有个问题就是信道系数只能是由高到低，大家可以试试，改成[0.227 0.46 0.688 0.46 0.227]这个是老师给我的仿真中常用的信道系数，这个成为归一化信道，就是系数平方和为1. 第二个程序没有涉及到信道系数，但是这个程序当中，在128个子载波中，前后有32个空载波，这个在OFDM中也是经常用的，这样可以降低误码率。 (And there are two programs, two are based on 4QAM modulation. But personally feel that the first is easier, because the writing is organized. I changed that procedure is based on the past. However, there is a problem in that there is only channel coefficients from high to low, we can try and change into [0.227 0.46 0.688 0.46 0.227] This is the teacher gave me the simulation channel coefficient commonly used, this became normalized channel, is coefficient of the square and is 1. The second program is not related to channel coefficients, but this program which, in the 128 sub-carriers, the before and after the 32 air carriers, the in OFDM is also often used, which can reduce the error rate.)

说明：  DWT数字水印算法研究和实现一种基于DCT和DWT结合的音频水印算法(Digital watermarking technique research based on DWT)

MATLAB实现霍夫曼编码对英文文本的解压缩程序(MATLAB Huffman coding for the English version of decompression procedures)

简单的数据降维算法（PCA）举例，构造随机的10维数据，降维成3维的。Sample可替换成用户数据(Examples of simple data reduction algorithms (PCA) are presented)