psd

not bad ofdm simulation

功率谱估计是利用有限长的数据估计信号的功率谱，广泛应用于各个领域。功率谱估计主要分为经典谱估计与现代谱估计。常用的经典谱估计方法有周期图法，相关法，周期图的改进法，常用的现代谱估计方法有最大熵谱估计，AR模型，MA模型，ARMA模型。经典谱估计适用于长序列的信号，其主要缺陷是描述功率谱波动的数字特征方差性能差，频率分辨率低，现代谱估计适用于短序列的信号，旨在改善谱估计的分辨率，并将其应用于实际地震资料的谱分析。 (Power spectrum estimation is the use of a finite length data to estimate the power spectrum of the signal, widely used in various fields. Power spectrum estimation is divided into classic and modern spectral estimation spectral estimation. Commonly used methods of classical periodogram spectrum estimation method, the relevant law, the cycle graph Improvement Act, commonly used in modern spectral estimation methods have maximum entropy spectral estimation, AR model, MA model, ARMA model. Classical spectral estimation applied to signal a long sequence, its main drawback is the fluctuation power spectrum describing digital signature variance performance is poor, the frequency resolution is low, modern spectral estimation applied to signal short sequences designed to improve spectral estimation resolution, and The analysis applied to real seismic data spectrum.)

全套球轴承拟静力学计算，以及在此基础上的生热量计算。可完美运行(whole package of quasi-static calculation and heat generation of ball bearing)

bit-interleaved coded modulation with 16 QAM

说明：  matlab图像处理常用命令收集，很有用的，可以省很多时间(matlab image processing common command collection, very useful, can save a lot of time)

该代码可生成阵列天线的发生天线方向图，以及列子阵接受图。(The code can generate array antenna transmitting map and also the receiving map of a Column. )

使用SIMULINK构建Turbo码仿真系统 A simulation system of Turbo Code using SIMULINK (北京科技大学信息工程学院)周贤(Turbo code constructed using SIMULINK simulation A simulation system of Turbo Code using SIMULINK (Beijing University of Science and Technology Information Technology Institute) Zhou)

gui ventana movil algoritmo de filtro

数字基带系统将数字信号从时域上看时数字滚降，需要画出滚降前后的波形展示出来。频域上带宽变化了。输入滤波器之前的波形与采样判决之后的波形。采样判决前的频谱。 采样判决后的码型。 2、眼图（采样判决之前的眼图）（信噪比大眼图清晰） 3、误码曲线，（横坐标时信噪比，纵坐标时误码率） 4、Arfa变化对误码特性的影响，变好还是变差(变好)，眼图清晰度变化（清晰），传递函数的带宽的变化。（带宽越大）(1.Digital baseband system point of view the digital signal from the time domain when the number of roll-off, you need to draw the waveform displayed before and after the roll-out. The frequency domain, the bandwidth change. Input filter and sample ruling before the wave after wave. Sample pre-judgment spectrum. Sampling pattern after the verdict. 2, the eye diagram (eye before sampling decision) (SNR big eye clear) 3, the error curve (abscissa when the signal to noise ratio, bit error rate when the vertical axis) 4, Arfa impact of change on BER performance, get better or worse (getting better), change of eye-definition (clarity), the transfer function of the bandwidth changes. (The greater the bandwidth))

对采样率进行变换，通过插入零，然后再做低通滤波，实现采样率的提高(Change the sampling rate by inserting zeros, and then do a low pass filter, the sampling rate to achieve the improvement of)