MAP_decoding

Easy C reference for C beginner

The Interleaved Frequency Division Multiple Ac- cess (IFDMA) scheme is based on compression, repetition and subsequent user dependent frequency shift of a modulated signal. Multiple access is enabled by the assignment of overlapping but mutually orthogonal subcarriers to each user. In this paper it is shown that IFDMA can be regarded as unitary precoded OFDMA with interleaved subcarriers. On the other hand, IFDMA is shown to be a CDMA variant with frequency domain orthogonal signature sequences and chip interleaving. Thus, it combines the advantages of single and multi carrier transmission such as low peak to average power ratio, orthogonality of the signals of different users even for transmission over a time dispersive channel and low complexity. Simulation results show the good performance of coded IFDMA transmission over a mobile radio channel for different data rates.

LDPC的译码算法，其中使用matlab和C的联合编程，C主要做了译码算法，并且有性能的仿真测试(LDPC decoding algorithm, including joint programming matlab and C, C major to do the decoding algorithm and performance simulation test)

二级模糊综合评价（以富营养化评价为例），matlab编写的(Two fuzzy comprehensive evaluation (as eutrophication assessment, for example), matlab prepared)

说明：  一些重要的matlab命令，关于多元正态分布(some matlab functions for multiple Gaussian distribution)

这是一个有关语音信号中的噪声降噪的原代码，结果可能有些不好(This is one of the voice signal noise of the original noise code, the result may be some bad)

最小频移键控（Minimum Shift Keying，MSK）是一种具有连续相位和最小频偏的数字调制技术。MSK的突出优点是信号具有恒定的包络和信号的相位连续性，频带利用率高，信号的功率谱在主瓣外衰减较快，这就使得它对邻波道干扰小。(MSK (Minimum Shift Keying) is a continuous phase and the minimum deviation of the digital modulation techniques. Outstanding advantage of MSK signals have constant envelope and continuous phase signals, high bandwidth efficiency and the signal power spectrum decreases rapidly outside the main lobe, this makes it a small adjacent channel interference.)

依据JPEG压缩标准的算法，对lena图像进行压缩，并恢复出原始图像，然后对照原始图像，对恢复出的图像进行客观评价：计算峰值信噪比PSNR及均方误差MSE。(language matlab jpeg picture compress)

基于MATLAB用于检测提取的语音信号的平均短时过零率的算法，可以方便的检测出是清音还是浊音。(Algorithm based on the MATLAB for detecting extracted speech signal average short-term zero-crossing rate, you can easily detect the voiceless or voiced.)

遗传算法解决TSP问题的一个不错的程序,在MATLAB下就可以应用,很好用(Genetic algorithm to solve TSP problems a good program, MATLAB can be applied, under, very good use)