06643301

对第一列为时间、第二列为数据的“data.txt”文件作归一化频率谱密度图。("Data.txt" file first as a time as data for the normalized frequency spectrum of the density map.)

code for some problems in smart antenna for wireless commnications

说明：  四点高斯积分公式在边界元分析法离散中的计算(Four the Gauss integral formula in boundary element analysis method in the calculation of discrete)

该代码为用gabor变换算法提取图像的纹理特征，用matlab编写，可应用于基于纹理的图像检索系统。其中还包含一篇gabor变换相关的文献(The code for the transformation algorithm using gabor texture features extracted using matlab preparation, can be applied to image retrieval system based on texture)

考虑L的三个不同值：L＝256（3个数据段），L＝128(7个数据段)和L=64（15个数据段）。各自的谱估计图如上图所示。可以明显的看到，加窗明显的减小了频谱上的假谱峰，但也更加进一步平滑了谱峰。所以，对于L＝64的情况，在ω＝0.8π的谱线可以很确定的辨认，但是那两个靠近的谱峰不容易区分。对于L＝128的情况，这种情况提供了在分离和检测间最好的均衡。当然，对于在L＝256时的情况，效果是更好的，能够从谱估计图上明显的分辨出三条谱线的存在以及它们幅度关系的强弱。 除了Welch法外，还可以采用对多个周期图求平均的功率谱估计方法的其他方法如Bartlett法等等，在功率谱估计上也能取得较好的结果。(consider three different values : L = 256 (3 data), L = 128 (7 data) and L = 64 (15 data). Their spectral estimation map as shown in Fig. It is clear to see that increase significantly decreasing window of the spectrum of false peaks, but much more to further smooth the peaks. Therefore, L = 64, in the case = 0.8 spectrum can determine the identification, but that the two peaks around is not easy to distinguish. L = 128 for the situation, which provided the separation and detection among the best balanced. Of course, L = 256 in the case, the effect is better, from the spectral estimation map clearly distinguish between the three lines of the existence and their relationship to the rate of strength. In addition to Welch law, but also can be used to map multiple cycle for the average power)

瑞丽衰落和莱斯衰落的对比 瑞利衰落（Rayleigh Fading）：在无线通信信道中，由于信号进行多径传播达到接收点处的场强来自不同传播的路径，各条路径延时时间是不同的，而各个方向分量波的叠加，又产生了驻波场强，从而形成信号快衰落称为瑞利衰落。瑞利衰落属于小尺度的衰落效应，它总是叠加于如阴影、衰减等大尺度衰落效应上。(rice fading and rayleigh fading)

指纹识别的源程序，用matlab程序实现的，可以参考看一下()

八位差分相移键控误码率分析的MATLAB程序(Eight differential phase shift keying bit error rate analysis of the MATLAB program)

程序为地震勘探资料处理方法中的数值模型模拟正演，方法为射线追踪(The program forward numerical model for seismic exploration data processing method in the simulation, for ray tracing method)

Part of the license plate recognition locator feature, STM32 all the information produced by the MP3, The final weight matrix is ??the filter coefficient.