Description: 用FFT 进行信号的频谱分析
1、高斯序列
2、衰减正弦序列
3、三角波序列
4、反三角序列-signals using the FFT spectrum analysis of one, two Gaussian sequence, the sequence of 3 attenuation sine, triangle wave sequence 4, anti - triangular series Platform: |
Size: 1027 |
Author:zl |
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Description: 设pn序列长度为Lc,为输入信号的Lc倍，输入带宽为f,则经过扩频后，信道中传输信号的带宽为Lc*f,.躁声也衰减为原来的1/Lc。在解调端用相同的pn序列进行解调。这样的好处是频带扩宽了，有利于对传送信号的保密，只有知道调制端的pn序列，才能正确地解调出信号；另外，由于躁声的衰减，在很大程度上降低了误码率-Based pn sequence length Lc, for the input signal Lc times, input bandwidth for f, then after a spread-spectrum, the channel bandwidth for the transmission signal Lc* f,. Attenuation would have been impatient for the original 1/Lc. Demodulation client in the same pn sequence demodulator. This advantage is widening the band, and is conducive to the transmission of signals remain confidential and will only know that side of pn sequence modulation in order to correctly signal demodulation In addition, since the sound attenuation impatient to a large extent reduce the bit error rate Platform: |
Size: 1024 |
Author:xuxiaodong10 |
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Description: 对于由2根或以上的传输线组成的网络，还会有传输线间的互参数，可以理解为近端串扰系数、远端串扰系统，注意在奇模激励和偶模激励下的S参数值不同。
需要说明的是，S参数表示的是全频段的信息，由于传输线的带宽限制，一般在高频的衰减比较大，S参数的指标只要在由信号的边缘速率表示的EMI发射带宽范围内满足要求就可以了。-For by two or more transmission lines composed of a network, there will be interaction between the transmission line parameters can be interpreted as near-end crosstalk coefficient, far-end crosstalk system, attention to incentives and even mode odd mode excitation of the S parameter value is different. Must be explained, S parameter represents the full spectrum of information, due to bandwidth limitations of transmission lines are generally relatively large in the high-frequency attenuation, S parameters of the target as long as indicated by the signal edge rates of the EMI emission bandwidth to meet the requirements within the scope on it. Platform: |
Size: 3422208 |
Author:sherry |
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Description: his article presents the characteristics of the signal used for the Galileo system with respect to those of the GPS system, as well as the adapted receiver architectures. An analysis of the sources of unintentional interference in the GPS ans GALILEO frequency bands reveals the existence of jammers
prone to inducing decreased performance. Different spectrum filtering techniques providing an attenuation of the effects of interference are presented in terms of the nature of the interference. Improvements in receiver architecture are proposed with conclusions indicating the necessity to evaluate these improvements in terms of efficiency and complexity Platform: |
Size: 756736 |
Author:s6igma |
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Description: 特征提取是模式识别中最重要的一个部分，这里提供的matlab代码计算一些基本的话音特征，而且，提供了一个简单的基于直方图的特征分类方法的实现。基本的特征包括：特征统计、Energy Entropy Standard Deviation (std)、均值信息熵、过零率检测、频谱衰减等等六个特征-Pattern recognition feature extraction is the most important part, here' s matlab code to compute some basic voice features, but also provides a simple classification method based on histogram characteristics of the implementation. Basic features include: Features and Statistics, Energy Entropy Standard Deviation (std), mean entropy, the zero-rate detection, attenuation, and so the six characteristics of the spectrum Platform: |
Size: 2048 |
Author:李韬 |
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Description: 本文介绍了OFDM技术及其功率谱的，并通过仿真研究了OFDM的功率谱密度特点。在同样条件下，增大子载波数目，会使信号带宽增加，带外衰减加快，功率谱密度图形更加接近于矩形。另外，添加循环前缀将使离散峰值谱线的值略微增大。-This article describes the OFDM technology and its power spectrum, and to study the characteristics of the power spectral density of the OFDM simulation. Under the same conditions, increasing the number of subcarriers, and will increase in signal bandwidth, band attenuation accelerate, and power spectral density pattern closer to the rectangle. Further, the cyclic prefix is added the value of the discrete peak spectrum will increase slightly...... Platform: |
Size: 144384 |
Author:王二 |
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Description: 1. 给一段原始的语音信号（可以是自己录制的一段语音），加上一频率为3.8kHz的高频余弦噪声和频率为3.6kHz的高频正弦噪声（幅度自己可以选择），用窗函数设计一滤波器（要求最小阻带衰减为50dB）对加噪后的语音信号进行滤波，画出滤波器的频率响应曲线，画出滤波前后的时域图和频谱图。
需要用到的函数：
fir1 用窗函数设计FIR滤波器的函数
2. 用GUI设计一界面（如图1所示）完成如下功能：
1） 输入一语音信号，画出语音信号的时域图和频谱图；
2） 对语音信号加噪处理，画出加噪后的时域图和频谱图；
3） 给定滤波器的性能指标，采用几种不同的方法设计滤波器对加噪信后进行滤波，画出各滤波器的频率响应曲线，画出滤波后的时域图和频谱图。
-1. to some of the original speech signal (which can be a voice you record yourself), plus a cosine frequency of 3.8kHz frequency noise and frequency of 3.6kHz frequency sinusoidal noise (in the range that they can choose), with a window function to design a filter (requires a minimum stop band attenuation is 50dB) after adding noise to the speech signal is filtered, the filter frequency response curve to draw, draw diagrams and time-domain spectrum before and after filtering. Need to use the function: function fir1 with window function design FIR filter design 2. Using a GUI interface (Figure 1) complete the following functions: 1) an input speech signal, the speech signal in the time domain to draw graphs and spectrum 2) adding noise to the speech signal processing, draw diagrams and time-domain plus noise spectrum after 3) to set the filter performance, using several different methods designed to filter letter after adding noise filtering, draw the frequency response curve of each Platform: |
Size: 1024 |
Author:longteng |
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Description: 共振解调法诊断轴承损伤类故障的原理概述如下:当轴承某一元件表面出现局部损伤时，在受载运行过程中要撞击与之相互作用的其它元件表面，产生冲击脉冲力，由于冲击脉冲力的频带很宽，必然包含轴承外圈、传感器甚至附加的谐振器等的固有频率而激起这个测振系统的高频固有振动。根据实际情况可以选择某一高频固有振动作为研究对象，通过中心频率等于该固有频率的带通滤波器把该固有振动分离出来。然后进行包络解调，去除高频衰减振动的频率成分，得到只包含故障特征信息的低频包络信号，对这一包络信号进行频谱分析便可以容易地诊断出轴承的故障来。-The principle of resonance demodulation method in the diagnosis of bearing damage such failure overview is as follows: when the bearing surface of a local damage, in the process of loading operation to hit with other elements of the interaction of surface, impact pulse power, due to the impact pulse frequency band is very wide, inevitably contains the bearing outer ring, sensors and even additional resonator and stir up the natural frequency of the vibration system of the high frequency vibration mode.A high frequency vibration mode can be selected according to actual situation as the research object, through the center frequency is equal to the natural frequency of the bandpass filter to separate the natural vibration.Then envelope demodulation, frequency components to remove the high frequency vibration attenuation, get only includes fault feature information of low frequency envelope signal, the envelope signal spectrum analysis can be easily diagnosed bearing failure. Platform: |
Size: 4096 |
Author:黄杰 |
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Description: 在一个移动通信系统中，发射信号是一个未调制的音频x(t)=cos(2πft)，其中f=f0+fi。设标称载波为f0=1GHz，并设fi =512Hz。假定移动用户在一个繁忙的高速公路上距离基站l公里处的地方，从开始从每小时60公里的速度开始，其速度（在0.01秒的时间间隔内测量）以1/2的概率随机的增加或减少1/10公里每小时。试仿真移动用户在这2s的时间间隔内所接收到的信号(及其频谱)。接收信号可以表示为：
y(t)=a(t)Cos[2π(fo+f1)(t-△t)]
式中 △(t)=d(t)/c
且 a(t)=k/d2(t)
在上面的表达式中d(t)是在t时刻基站与移动用户的距离，c是光速，△(t)是传播延迟，而a(t)是信号在t时刻的衰减，并假设在这2s内a(t)是一个常数。利用复低通等效模型来进行仿真。-In a mobile communication system, the transmitted signal is an unmodulated audio x (t) = cos (2πft), where f = f0+ fi. Let nominal carrier of f0 = 1GHz, and set fi = 512Hz. Assume that mobile users on a busy motorway station l kilometers place, starting the beginning of 60 kilometers per hour, the speed (measured in 0.01 second interval) to increase the probability of a random 1/2 or reducing 1/10 km/h. Simulation test signal which the mobile subscriber in the 2s time intervals of the received (and its spectrum). The received signal can be expressed as:
y (t) = a (t) Cos [2π (fo+ f1) (t- △ t)]
Where △ (t) = d (t)/c
And a (t) = k/d2 (t)
In the above expression, d (t) at time t is a base station and a mobile user s distance, c is the speed of light, △ (t) is the propagation delay, and a (t) is the attenuation of the signal at time t, and assuming that 2s within a (t) is a constant. Using complex low-pass equivalent model for emulation. Platform: |
Size: 2048 |
Author:何希 |
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Description: 到达过程是的泊松过程，基于互功率谱的时延估计，考虑雨衰 阴影 和多径影响，部分实现了追踪测速迭代松弛算法，这个有中文注释，看得明白，PLS部分最小二乘工具箱。-Arrival process is a Poisson process, Based on the time delay estimation of power spectrum, Consider shadow rain attenuation and multipath effects Partially achieved tracking speed iterative relaxation algorithm, The Chinese have a comment, understand it, PLS PLS toolbox. Platform: |
Size: 6144 |
Author:fxdfin |
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Description: 可以得到很精确的幅值、频率、相位估计，主要为数据分析和统计，正确率可以达到98％，旋转机械二维全息谱计算，是小学期课程设计的题目，考虑雨衰 阴影 和多径影响。- You can get a very accurate amplitude, frequency, phase estimation, Mainly for data analysis and statistics, Accuracy can reach 98 , Rotating machinery 2-d holographic spectrum calculation, Is the topic of the elementary school stage curriculum design, Consider shadow rain attenuation and multipath effect. Platform: |
Size: 8192 |
Author:massqw |
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Description: 是学习PCA特征提取的很好的学习资料，关于神经网络控制，分析了该信号的时域、频域、倒谱，循环谱等,考虑雨衰 阴影 和多径影响，线性调频脉冲压缩的Matlab程序,研究生时的现代信号处理的作业。- Is a good learning materials to learn PCA feature extraction, On neural network control, Analysis of the signal time domain, frequency domain, cepstrum, cyclic spectrum, etc. Consider shadow rain attenuation and multipath effects LFM pulse compression of the Matlab program, Modern signal processing jobs when the graduate. Platform: |
Size: 4096 |
Author:dvpmmm |
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Description: 基于互功率谱的时延估计，考虑雨衰 阴影 和多径影响，研究生时的现代信号处理的作业，有循环检测，周期性检测，matlab程序运行时导入数据文件作为输入参数。-Based on the time delay estimation of power spectrum, Consider shadow rain attenuation and multipath effects Modern signal processing jobs when the graduate, There are cycle detection, periodic testing, Import data files as input parameters matlab program is running. Platform: |
Size: 6144 |
Author:yyfzmiae |
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Description: 分析了该信号的时域、频域、倒谱，循环谱等,考虑雨衰 阴影 和多径影响，各种资源分配算法实现，这个有中文注释，看得明白，包括数据分析、绘图等等。- Analysis of the signal time domain, frequency domain, cepstrum, cyclic spectrum, etc. Consider shadow rain attenuation and multipath effects Various resource allocation algorithm, The Chinese have a comment, understand it, Data analysis, plotting, etc.. Platform: |
Size: 7168 |
Author:cyrfhtgrf |
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Description: 包含光伏电池模块、MPPT模块、BOOST模块、逆变模块，包括脚本文件和函数文件形式，分析了该信号的时域、频域、倒谱，循环谱等,考虑雨衰 阴影 和多径影响，用MATLAB实现动态聚类或迭代自组织数据分析。-PV modules contain, MPPT module, BOOST module, inverter module, Including script files and function files in the form, Analysis of the signal time domain, frequency domain, cepstrum, cyclic spectrum, etc. Consider shadow rain attenuation and multipath effects Using MATLAB dynamic clustering or iterative self-organizing data analysis. Platform: |
Size: 6144 |
Author:mvaxhjyui |
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Description: 考虑雨衰 阴影 和多径影响，抑制载波型差分相位调制，MIMO OFDM matlab仿真,旋转机械二维全息谱计算，仿真效果非常好，真的是一个好程序。- Consider shadow rain attenuation and multipath effects Suppressed carrier type differential phase modulation, MIMO OFDM matlab simulation, Rotating machinery 2-d holographic spectrum calculation, Simulation of the effect is very good, Really is a good program. Platform: |
Size: 6144 |
Author:ukyzecuut |
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